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1.
Nat Commun ; 15(1): 3961, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38729932

RESUMEN

Mechanically interlocked molecules (MIMs) including famous catenanes show switchable physical properties and attract continuous research interest due to their potential application in molecular devices. The advantages of using spin crossover (SCO) materials here are enormous, allowing for control through diverse stimuli and highly specific functions, and enabling the transfer of the internal dynamics of MIMs from solution to solid state, leading to macroscopic applications. Herein, we report the efficient self-assembly of catenated metal-organic frameworks (termed catena-MOFs) induced by stacking interactions, through the combination of rationally selected flexible and conjugated naphthalene diimide-based bis-pyridyl ligand (BPND), [MI(CN)2]- (M = Ag or Au) and Fe2+ in a one-step strategy. The obtained bimetallic Hofmann-type SCO-MOFs [FeII(BPND){Ag(CN)2}2]·3CHCl3 (1Ag) and [FeII(BPND{Au(CN)2}2]·2CHCl3·2H2O (1Au) possess a unique three-dimensional (3D) catena-MOF constructed from the polycatenation of two-dimensional (2D) layers with hxl topology. Both complexes undergo thermal- and light-induced SCO. Significantly, abnormal increases in the maximum emission intensity and dielectric constant can be detected simultaneously with the switching of spin states. This research opens up SCO-actuated bistable MIMs that afford dual functionality of coupled fluorescence emission and dielectricity.

2.
Adv Mater ; : e2402666, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632497

RESUMEN

Shaping room temperature phosphorescence (RTP) materials into 3D bodies is important for stereoscopic optoelectronic displays but remains challenging due to their poor processability and mechanical properties. Here, konjac glucomannan (KGM) is employed to anchor arylboronic acids with various π conjugations via a facile B─O covalent reaction to afford printable inks, using which full-color high-fidelity 3D RTP objects with high mechanical strength can be obtained via direct ink writing-based 3D printing and freeze-drying. The doubly rigid structure supplied by the synergy of hydrogen bonding and B─O covalent bonding can protect the triplet excitons; thus, the prepared 3D RTP object shows a striking lifetime of 2.14 s. The printed counterparts are successfully used for 3D anti-counterfeiting and can be recycled and reprinted nondestructively by dissolving in water. This success expands the scope of printable 3D luminescent materials, providing an eco-friendly platform for the additive manufacturing of sophisticated 3D RTP architectures.

3.
Nat Commun ; 15(1): 2653, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38531845

RESUMEN

Realization of higher-order multistates with mutual interstate switching in ferroelectric materials is a perpetual drive for high-density storage devices and beyond-Moore technologies. Here we demonstrate experimentally that antiferroelectric van der Waals CuInP2S6 films can be controllably stabilized into double, quadruple, and sextuple polarization states, and a system harboring polarization order of six is also reversibly tunable into order of four or two. Furthermore, for a given polarization order, mutual interstate switching can be achieved via moderate electric field modulation. First-principles studies of CuInP2S6 multilayers help to reveal that the double, quadruple, and sextuple states are attributable to the existence of respective single, double, and triple ferroelectric domains with antiferroelectric interdomain coupling and Cu ion migration. These findings offer appealing platforms for developing multistate ferroelectric devices, while the underlining mechanism is transformative to other non-volatile material systems.

4.
ACS Appl Mater Interfaces ; 16(12): 15133-15142, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38488729

RESUMEN

Dynamic control of ultralong organic room-temperature phosphorescence (UORTP) is a charming target. Herein, we report a stimuli-responsive phosphorescence unit 7H-indolo[2,3-c]quinoline (NBCz) and its derivatives (PCBNBCz, FSO2NBCz, and N2BCzSO2NBCz) that show photo- and oxygen- synergistically induced afterglow activation and afterglow color change in the PMMA film. PCBNBCz and FSO2NBCz feature a donor-acceptor (D-A) structure, and N2BCzSO2NBCz features acceptor-bridged two different phosphorescence units (NBCz and N2BCz). The photoactivated UORTP of PCBNBCz and FSO2NBCz arises from the photoinduced consumption of oxygen in the PMMA film. It is clear that the phosphorescence unit NBCz contributes to subsequent photoinduced UORTP color change because the NBCz-doped PMMA film shows the same UORTP color change process. ESR and HRMS measurements confirmed that oxidation of NBCz occurs at the nitrogen atom of the quinoline ring via photogenerated superoxide radicals, which results in the UORTP color change. TDDFT calculations proved that after oxidation of NBCz, the T1 energy level declines significantly. Furthermore, photocontrolled selective expression of phosphorescence units is achieved in the case of N2BCzSO2NBCz. After further UV irradiation, oxidation of NBCz happened, and the oxidized form N2BCzSO2NBCz-O emitted the intrinsic orange UORTP of NBCz-O selectively and screened the intrinsic yellowish-green UORTP of N2BCz. Finally, multilevel photolithography can be demonstrated based on the photoactivated UORTP and the photoinduced UORTP color change. This work may give a deep insight into organic phosphorescence and pave a simple way for the development of stimulus-responsive smart UORTP materials.

5.
Medicine (Baltimore) ; 103(13): e37542, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38552082

RESUMEN

In this retrospective study conducted at Sichuan Jinxin Xinan Women and Children's Hospital spanning January 2015 to December 2021, our objective was to investigate the impact of embryo cryopreservation duration on outcomes in frozen embryo transfer. Participants, totaling 47,006 cycles, were classified into 3 groups based on cryopreservation duration: ≤1 year (Group 1), 1 to 6 years (Group 2), and ≥6 years (Group 3). Employing various statistical analyses, including 1-way ANOVA, Kruskal-Wallis test, chi-square test, and a generalized estimating equation model, we rigorously adjusted for confounding factors. Primary outcomes encompassed clinical pregnancy rate and Live Birth Rate (LBR), while secondary outcomes included biochemical pregnancy rate, multiple pregnancy rate, ectopic pregnancy rate, early and late miscarriage rates, preterm birth rate, neonatal birth weight, weeks at birth, and newborn sex. Patient distribution across cryopreservation duration groups was as follows: Group 1 (40,461 cycles), Group 2 (6337 cycles), and Group 3 (208 cycles). Postcontrolling for confounding factors, Group 1 exhibited a decreased likelihood of achieving biochemical pregnancy rate, clinical pregnancy rate, and LBR (OR < 1, aOR < 1, P < .05). Furthermore, an elevated incidence of ectopic pregnancy was observed (OR > 1, aOR > 1), notably significant after 6 years of freezing time [aOR = 4.141, 95% confidence intervals (1.013-16.921), P = .05]. Cryopreservation exceeding 1 year was associated with an increased risk of early miscarriage and preterm birth (OR > 1, aOR > 1). No statistically significant differences were observed in birth weight or sex between groups. However, male infant birth rates were consistently higher than those of female infants across all groups. In conclusion, favorable pregnancy outcomes align with embryo cryopreservation durations within 1 year, while freezing for more than 1 year may diminish clinical pregnancy and LBRs, concurrently elevating the risk of ectopic pregnancy and preterm birth.


Asunto(s)
Aborto Espontáneo , Embarazo Ectópico , Nacimiento Prematuro , Niño , Embarazo , Femenino , Masculino , Recién Nacido , Humanos , Resultado del Embarazo/epidemiología , Estudios Retrospectivos , Aborto Espontáneo/epidemiología , Aborto Espontáneo/etiología , Peso al Nacer , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/etiología , Nacimiento Vivo , Transferencia de Embrión/efectos adversos , Índice de Embarazo , Criopreservación , Embarazo Ectópico/epidemiología , Embarazo Ectópico/etiología
6.
IEEE J Biomed Health Inform ; 28(2): 1012-1021, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38090820

RESUMEN

The process of brain aging is intricate, encompassing significant structural and functional changes, including myelination and iron deposition in the brain. Brain age could act as a quantitative marker to evaluate the degree of the individual's brain evolution. Quantitative susceptibility mapping (QSM) is sensitive to variations in magnetically responsive substances such as iron and myelin, making it a favorable tool for estimating brain age. In this study, we introduce an innovative 3D convolutional network named Segmentation-Transformer-Age-Network (STAN) to predict brain age based on QSM data. STAN employs a two-stage network architecture. The first-stage network learns to extract informative features from the QSM data through segmentation training, while the second-stage network predicts brain age by integrating the global and local features. We collected QSM images from 712 healthy participants, with 548 for training and 164 for testing. The results demonstrate that the proposed method achieved a high accuracy brain age prediction with a mean absolute error (MAE) of 4.124 years and a coefficient of determination (R2) of 0.933. Furthermore, the gaps between the predicted brain age and the chronological age of Parkinson's disease patients were significantly higher than those of healthy subjects (P<0.01). We thus believe that using QSM-based predicted brain age offers a more reliable and accurate phenotype, with the potentiality to serve as a biomarker to explore the process of advanced brain aging.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Humanos , Preescolar , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Envejecimiento , Hierro
7.
Small ; 20(13): e2309131, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37967324

RESUMEN

Sustainable long-lived room temperature phosphorescence (RTP) materials with color-tunable afterglows are attractive but rarely reported. Here, cellulose is reconstructed by directed redox to afford ample active hydroxyl groups and water-solubility; arylboronic acids with various π conjugations can be facilely anchored to reconstructed cellulose via click chemistry within 1 min in pure water, resulting in full-color tunable RTP cellulose. The rigid environment provided by the B─O covalent bonds and hydrogen bonds can stabilize the triplet excitons, thus the target cellulose displays outstanding RTP performances with the lifetime of 2.67 s, phosphorescence quantum yield of 9.37%, and absolute afterglow luminance of 348 mcd m-2. Furthermore, due to the formation of various emissive species, the smart RTP cellulose shows excitation- and time-dependent afterglows. Taking advantages of sustainability, ultralong lifetime, and full-color tunable afterglows, et al, the environmentally friendly RTP cellulose is successfully used for nontoxic afterglow inks, delay lighting, and afterglow display.

8.
J Am Chem Soc ; 146(2): 1294-1304, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38054299

RESUMEN

Achieving time-dependent phosphorescence color (TDPC) in organic materials is attractive but extremely challenging due to the nonradiative decay and modulation puzzle of triplet state. Herein, xylan, a hemicellulose waste from the paper mill, was used to construct carbonized polymer dots (CPDs) with clusterization-triggered room-temperature phosphorescence (RTP). CPDs were endowed with tuneable triplet energy levels by through-space conjugation of heteroatom groups, which could be confined in silica to simultaneously activate surface oxide-related low-energy and cross-linked core N-related high-energy emissive centers. Thus, the blue emissive center with a lifetime of 425.6 ms and green emissive center with a longer lifetime of 1506 ms coexisted in the confined CPDs; the former was the dominant contribution to RTP at first, and the latter became dominant over time, leading to a typical TDPC evolution with large color contrast from blue to blue-green and then to green. Meanwhile, the TDPC could remain unobstructed after the confined CPDs were soaked in water for more than a month. The CPDs were successfully applied in location and deformation imaging of hydrogel and advanced dynamic information encryption and anticounterfeiting. The work may shed new light on the design of TDPC materials and broaden the high-value use of paper-mill waste xylan.

9.
Am J Obstet Gynecol ; 230(4): 436.e1-436.e12, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38135094

RESUMEN

BACKGROUND: The influence of SARS-CoV-2 infection after embryo transfer on early pregnancy outcomes in in vitro fertilization or intracytoplasmic sperm injection-embryo transfer treatment remains inadequately understood. This knowledge gap endures despite an abundance of studies investigating the repercussions of preceding SARS-CoV-2 infection on early pregnancy outcomes in spontaneous pregnancies. OBJECTIVE: This study aimed to investigate the association between SARS-CoV-2 infection within 10 weeks after embryo transfer and early pregnancy outcomes in patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment. STUDY DESIGN: This prospective cohort study was conducted at a single public in vitro fertilization center in China. Female patients aged 20 to 39 years, with a body mass index ranging from 18 to 30 kg/m2, undergoing in vitro fertilization/intracytoplasmic sperm injection treatment, were enrolled between September 2022 and December 2022, with follow-up extended until March 2023. The study tracked SARS-CoV-2 infection time (≤14 days, ≤28 days, and ≤10 weeks after embryo transfer), symptoms, vaccination status, the interval between vaccination and embryo transfer, and early pregnancy outcomes, encompassing biochemical pregnancy rate, implantation rate, clinical pregnancy rate, and early miscarriage rate. The study used single-factor analysis and multivariate logistic regression to examine the association between SARS-CoV-2 infection status, along with other relevant factors, and the early pregnancy outcomes. RESULTS: A total of 857 female patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment were analyzed. In the first stage, SARS-CoV-2 infection within 14 days after embryo transfer did not have a significant negative association with the biochemical pregnancy rate (adjusted odds ratio, 0.74; 95% confidence interval, 0.51-1.09). In the second stage, SARS-CoV-2 infection within 28 days after embryo transfer had no significant association with the implantation rate (36.6% in infected vs 44.0% in uninfected group; P=.181). No statistically significant association was found with the clinical pregnancy rate after adjusting for confounding factors (adjusted odds ratio, 0.69; 95% confidence interval, 0.56-1.09). In the third stage, SARS-CoV-2 infection within 10 weeks after embryo transfer had no significant association with the early miscarriage rate (adjusted odds ratio, 0.77; 95% confidence interval, 0.35-1.71). CONCLUSION: Our study suggests that SARS-CoV-2 infection within 10 weeks after embryo transfer may not be negatively associated with the biochemical pregnancy rate, implantation rate, clinical pregnancy rate, and early miscarriage rate in patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment. It is important to note that these findings are specific to the target population of in vitro fertilization/intracytoplasmic sperm injection patients aged 20 to 39 years, without previous SARS-CoV-2 infection, and with a body mass index of 18 to 30 kg/m2. This information offers valuable insights, addressing current concerns and providing a clearer understanding of the actual risk associated with SARS-CoV-2 infection after embryo transfer.


Asunto(s)
Aborto Espontáneo , COVID-19 , Embarazo , Humanos , Masculino , Femenino , Resultado del Embarazo , Aborto Espontáneo/epidemiología , Aborto Espontáneo/etiología , Estudios Prospectivos , COVID-19/terapia , COVID-19/etiología , SARS-CoV-2 , Semen , Fertilización In Vitro/efectos adversos , Transferencia de Embrión , Índice de Embarazo , Estudios Retrospectivos
10.
Adv Mater ; 36(14): e2312425, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38146671

RESUMEN

2D transition metal dichalcogenides (TMDCs) are considered as promising materials in post-Moore technology. However, the low photoluminescence quantum yields (PLQY) and single carrier polarity due to the inevitable defects during material preparation are great obstacles to their practical applications. Here, an extraordinary defect engineering strategy is reported based on first-principles calculations and realize it experimentally on WS2 monolayers by doping with IIIA atoms. The doped samples with large sizes possess both giant PLQY enhancement and effective carrier polarity modulation. Surprisingly, the high PL emission maintained even after one year under ambient environment. Moreover, the constructed p-n homojunctions shows high rectification ratio (≈2200), ultrafast response times and excellent stability. Meanwhile, the doping strategy is universally applicable to other TMDCs and dopants. This smart defect engineering strategy not only provides a general scheme to eliminate the negative influence of defects, but also utilize them to achieve desired optoelectronic properties for multifunctional applications.

11.
Inorg Chem ; 62(48): 19690-19697, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38044827

RESUMEN

Owing to the exterior self-trapped excitons (STEs) with adjustable fluorescence beams, low-dimensional ns2-metal halides have recently received considerable attention in solid-state light-emitting applications. However, the photoluminescence (PL) mechanism in metal halides remains a major challenge in achieving high efficiency and controllable PL properties because the excited-state energy of ns2 conformational ions varies inhomogeneously with their coordination environments. Here, a novel zero-dimensional (0D) lead-free bismuth-based Rb3BiCl6·0.5H2O crystal was reported as a pristine crystal to modulate the optical properties. By doping Sb3+ ions with 5s2 electrons into Rb3BiCl6·0.5H2O crystals, bright orange emission at room temperature was obtained with a photoluminescence quantum yield of 39.7%. Optical characterizations and theoretical studies show that the Sb3+ doping can suppress the strong exciton-phonon coupling, optimize the electronic energy band structure, improve the thermal activation energy, soften the structural lattice of the host crystals, deepen the STE states, and ultimately lead to strong photoluminescence. This work manifests a fruitful manipulation in ripening bismuth-based halides with high-efficiency PL properties, and the PL enhancement mechanisms will guide future research in the exploration of emerging luminescent materials.

12.
Iran J Public Health ; 52(11): 2272-2285, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38106842

RESUMEN

Background: Many epidemiological studies have explored the relationship between single-nucleotide polymorphism and hepatocellular carcinoma (HCC). However, the results remain controversial. We performed a large-scale meta-analysis to draw a more precise estimation of the aforementioned association. Methods: Studies on the association between microRNA (MIR) polymorphisms and HCC risk that had been published up to Sep 30, 2021 were identified by searching the PubMed, Cochrane Library, Google Scholar, Web of Science, and Chinese Biomedical Literature electronic databases and the Excerpta Medical Database. The association between MIR polymorphisms and HCC risk was assessed using odds ratios (ORs) and their 95% confidence intervals (CIs). Results: Overall, 29 studies, with a total of 9,263 cases and 10,875 controls, were included in our meta-analysis. MicroRNA149 (MIR149) significantly decreased the risk of developing HCC on the overall population (homozygous model CC vs. TT: OR = 0.703, 95% CI = 0.549-0.899, P = 0.005), and microRNA 196 (MIR196) significantly decreased the risk of developing HCC on the overall population (recessive model TT vs. CT+CC: OR = 0.864, 95% CI = 0.751-0.993, P = 0.04) and on Caucasians (OR = 0.613, 95% CI = 0.414-0.907, P = 0.014). Conclusion: The MIR149 and MIR196 polymorphisms are the protect factors of developing HCC. The conduct of multi-center and multi-region studies with gene-gene, gene-environment should be considered.

13.
ACS Appl Mater Interfaces ; 15(47): 54732-54742, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37964465

RESUMEN

We successfully tune ultralong organic room-temperature phosphorescence (UORTP) by a simple strategy of precisely modifying nitrogen atoms on Phosphorescence Units, and colorful ultralong phosphorescence can be achieved. We for the first time investigate the structure-function relationship between phosphorescence properties and molecular structures of Phosphorescence Units. With BCz and BCz-1 as comparison, eight new Phosphorescence Units were synthesized by introducing one or two nitrogen atoms to the naphthalene moiety. For all the 10 Phosphorescence Units, their room-temperature ultralong phosphorescence in the PMMA film should be assigned to monomer phosphorescence from intrinsic T1 decay. For Phosphorescence Units series I (BCz, NBCz-1, NBCz-2, NBCz-3, NBCz-4, NBCz-5, and NBCz-6), introducing one nitrogen atom to the naphthalene moiety can significantly affect the phosphorescence properties of Phosphorescence Units, and the effect is quite complicated. For modification on the inner ring, the T1 energy level of NBCz-1 decreases, and the red shift of UORTP occurs while the T1 energy level of NBCz-2 increases and the blue shift of UORTP happens. For modification on the outer ring, no phosphorescence color change is observed for NBCz-3 and NBCz-4, but their phosphorescence lifetimes vary notably due to different intersystem crossing efficiencies; as the modification site approaches the central five-member ring, the T1 energy levels of NBCz-5 and NBCz-6 decrease, and their UORTP red shifts dramatically. For Phosphorescence Units series II (BCz, 2NBCz, BCz-1, and 2NBCz-1), introducing two nitrogen atoms to the outer six-member ring reduces energy level of T1 excitons and leads to incredible red shift of UORTP for BCz and 2NBCz while surprisingly energy levels of T1 excitons rise and UORTP blue shifts for BCz-1 and 2NBCz-1. Under the condition of proper modification sites, it is true that the more the additional nitrogen atoms, the more red-shifted the ultralong phosphorescence. This study may expand our knowledge of organic phosphorescence and lay the foundation for its future applications.

14.
Commun Biol ; 6(1): 1195, 2023 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-38001377

RESUMEN

Type VI secretion systems (T6SSs) deliver effectors into target cells. Besides structural and effector proteins, many other proteins, such as adaptors, co-effectors and accessory proteins, are involved in this process. MIX domains can assist in the delivery of T6SS effectors when encoded as a stand-alone gene or fused at the N-terminal of the effector. However, whether there are other conserved domains exhibiting similar encoding forms to MIX in T6SS remains obscure. Here, we scanned publicly available bacterial genomes and established a database which include 130,825 T6SS vgrG loci from 45,041 bacterial genomes. Based on this database, we revealed six domain families encoded within vgrG loci, which are either fused at the C-terminus of VgrG/N-terminus of T6SS toxin or encoded by an independent gene. Among them, DUF2345 was further validated and shown to be indispensable for the T6SS effector delivery and LysM was confirmed to assist the interaction between VgrG and the corresponding effector. Together, our results implied that these widely distributed domain families with similar genetic configurations may be required for the T6SS effector recruitment process.


Asunto(s)
Sistemas de Secreción Tipo VI , Humanos , Sistemas de Secreción Tipo VI/genética , Sistemas de Secreción Tipo VI/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
15.
Science ; 381(6664): 1295, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37733867
16.
Transplant Direct ; 9(9): e1530, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37636486

RESUMEN

Background: Women are more likely than men to be living kidney donors. We summarized the evidence concerning the reasons behind sex and gender disparities in living kidney donation (LKD). Methods: A scoping review of quantitative and qualitative evidence on reasons for sex and gender disparities in LKD was conducted from inception to March 2023. Results: Of 1123 studies screened, 45 were eligible for inclusion. Most studies were from North America, Europe, and Central Asia (n = 33, 73%). A predominance of women as living donors (55%-65%) was observed in 15 out of 18 (83%) studies. Reasons for sex and gender disparities in LKD included socioeconomic, biological, and cognitive or emotional factors. A gendered division of roles within the families was observed in most studies, with men being the primary income earner and women being the main caregiver. Fear of loss of income was a barrier to male donation. Human leukocyte antigen sensitization through pregnancy in female recipients precluded male partner donation, whereas female donation was supported by altruism and a positive attitude toward LKD. Conclusions: Sex imbalance in LKD is prevalent, with a predominance of women as living donors. Such disparities are driven by societal and cultural perceptions of gender roles, pregnancy-induced sensitization, and attitudes toward donation and at least some of these factors are modifiable. Donor compensation to support predonation assessments and income loss, implementation of innovative desensitization treatments, promotion of paired kidney exchange program, and targeted educational initiatives to promote equitable living donation may help to close the gender gap in LKD.

17.
Eur J Radiol ; 167: 111030, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37579561

RESUMEN

PURPOSE: Abnormalities in free water (FW) and susceptibility values exist in the substantia nigra (SN) of patients with Parkinson's disease (PD), but their role in characterizing the disease processes remains uncertain. This study investigated these values at various SN locations and stages of PD, and their relationship with clinical symptoms. METHOD: FW and quantitative susceptibility mapping (QSM) values were evaluated in the anterior and posterior SN, along with swallow-tail-sign (STS) ratings, in patients with PD (early-stage: n = 39; middle-to-advanced-stage: n = 97) and healthy controls (n = 82). The correlation between these indices and motor and non-motor symptoms, and their capability to distinguish PD from healthy controls, were also examined. RESULTS: Increased FW in the anterior and posterior SN and increased QSM values in the posterior SN were observed in both early-stage and middle-to-advanced-stage PD patients (p < 0.05). However, there was no significant difference in FW, QSM values, or STS ratings among patients at different stages. FW and QSM values correlated with motor symptoms in middle-to-advanced-stage patients (p < 0.05), while STS ratings were associated with non-motor symptoms (p < 0.05). Additionally, combining FW and QSM values in the posterior SN with STS ratings in logistic regression showed better performance in distinguishing PD (area under curve = 0.931) compared to using STS ratings alone (area under curve = 0.880). CONCLUSIONS: Findings suggest elevated FW and iron content in PD at different stages, with dissociation in SN location between the two indices. Elevated signals are related to the motor symptom severity in middle-to-advanced-stage patients, and may have the potential for PD diagnosis and symptom assessment.


Asunto(s)
Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico por imagen , Imagen por Resonancia Magnética , Hierro , Sustancia Negra/diagnóstico por imagen , Agua
18.
Sensors (Basel) ; 23(13)2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37447823

RESUMEN

This study investigated the trajectory-planning problem of a six-axis robotic arm based on deep reinforcement learning. Taking into account several characteristics of robot motion, a multi-objective optimization approach is proposed, which was based on the motivations of deep reinforcement learning and optimal planning. The optimal trajectory was considered with respect to multiple objectives, aiming to minimize factors such as accuracy, energy consumption, and smoothness. The multiple objectives were integrated into the reinforcement learning environment to achieve the desired trajectory. Based on forward and inverse kinematics, the joint angles and Cartesian coordinates were used as the input parameters, while the joint angle estimation served as the output. To enable the environment to rapidly find more-efficient solutions, the decaying episode mechanism was employed throughout the training process. The distribution of the trajectory points was improved in terms of uniformity and smoothness, which greatly contributed to the optimization of the robotic arm's trajectory. The proposed method demonstrated its effectiveness in comparison with the RRT algorithm, as evidenced by the simulations and physical experiments.


Asunto(s)
Procedimientos Quirúrgicos Robotizados , Procedimientos Quirúrgicos Robotizados/métodos , Algoritmos , Aprendizaje , Movimiento (Física) , Motivación
19.
JAMA Netw Open ; 6(7): e2323495, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37450305

RESUMEN

This cohort study assesses the association of maternal hepatitis B virus (HBV) serostatus with pregnancy outcomes in women undergoing freeze-thaw embryo transfer (FET).


Asunto(s)
Hepatitis B , Resultado del Embarazo , Embarazo , Femenino , Humanos , Virus de la Hepatitis B , Transferencia de Embrión , Índice de Embarazo
20.
Angew Chem Int Ed Engl ; 62(32): e202303262, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37259616

RESUMEN

Highly adjustable photonic modules were constructed based on the heterostructures crystals of a new series of donor-acceptor metal-organic framework (D-A MOF) featuring highly tunable thermally activated delayed fluorescence (TADF). By introducing N-phenylcarbazole and derivatives as donor guests into the acceptor host NKU-111, highly tunable through-space charge transfer based TADF could be achieved through the engineering of heavy atom effect, which result in modulatable emission wavelength (540 to 600 nm) and enhanced quantum yield (up to 30.86 %). Furthermore, by rationally integrating the D-A MOFs with distinctive emissions, rod-like heterostructures crystals featuring excitation position dependent tip emissions in wide wavelength range (495 to 598 nm) could be fabricated, which could serve as highly potential photonic modules for photonic circuit applications.

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