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1.
Nanomaterials (Basel) ; 14(13)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38998732

RESUMEN

Highly sensitive and specific biomarker detection is of outstanding importance for the diagnosis and treatment of cancers. Herein, we developed robust photoelectrochemical (PEC) biosensors with low background noise and high sensitivity based on a heterojunction, which can improve semiconductor photoelectric properties by limiting the recombination of photogenerated electron-hole pairs and successfully widening the range of light absorption. Alpha-fetoprotein (AFP) was used as a target model to examine the analytical performances of the designed PEC biosensors. ZnO/Cs3MnBr5 heterogeneous film with a uniform porous structure and large surface area enhanced electron transfer and biomolecule immobilization, and significantly increased the photocurrent response. Under the optimal conditions, the designed PEC biosensor exhibited a linear detection range of 0.01-500 ng/mL and a detection limit of 12 pg/mL. In addition, this PEC biosensor performed well when testing human serum samples and exhibited good repeatability, stability over time, and specificity, showing enormous potential for the detection of cancer markers in future biological and clinical research.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39075656

RESUMEN

INTRODUCTION: The anterior and lateral position of the anterolateral papillary muscle (ALPM) has found to be reached with better catheter stability and less mechanical bumping via the transseptal (TS) compared to the retrograde aortic (RA) approach. The aim of this study is to compare the TS and RA approaches on mapping and ablation of ventricular arrhythmias (VAs) arising from ALPMs. METHODS: Thirty-two patients with ALPM-VAs undergoing mapping and ablation via the TS approach were included and compared with 31 patients via the RA approach within the same period. Acute success was compared, as well as other outcomes including misinterpreted mapping results due to bumping, radiofrequency (RF) attempts, procedural time and success rate at 12-month follow-up. RESULTS: Acute success was achieved in more cases in the TS group (96.4% vs. 72.0%, p = .020). During activation mapping, bump-provoked premature ventricular complexes (PVCs) misinterpreted as clinical PVCs were more common in the RA group (30.0% vs. 58.3%, p = .036), leading to more RF attempts (3.5 ± 2.7 vs. 7.2 ± 6.8, p = .006). Suppression of VAs were finally achieved in the unsuccessful cases by changing to the alternative approach, but the procedural time was significantly less in the TS group (90.0 ± 33.0 vs. 113.7 ± 41.1 min, p = .027) with less need to change the approach, although follow-up success rates were similar (75.0% vs. 71.0%, p = .718). CONCLUSION: A TS rather than RA approach as the initial approach appears to facilitate mapping and ablation of ALPM-VAs, specifically by decreasing the possibility of misleading mapping results caused by bump-provoked PVC, and increase the acute success rate thereby.

3.
J Arthroplasty ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38851406

RESUMEN

BACKGROUND: The present study aimed to identify the risk factors of periprosthetic femoral fracture (PFF) after cementless total hip arthroplasty and rank them based on importance. METHODS: The age, sex, body mass index (BMI), osteoporosis, canal flare index (CFI), canal bone ratio (CBR), canal calcar ratio (CCR), stem design, and stem canal fill ratio (P1, P2, P3, and P4) of the proximal femoral medullary cavity of 111 total hip arthroplasty patients who had PFF and 388 who did not have PFF were analyzed. Independent-samples student t-tests were used for continuous variables, and Chi-square tests were used for categorical variables. The importance rankings of influencing factors were assessed using a random forest algorithm. Dimensionally reduced variables were then incorporated into a binary logistic regression model to determine the PFF-related risk factors. RESULTS: The mean age, BMI, CBR, CCR, and incidence of osteoporosis were higher in cases of PFF (all P < .001), while the mean CFI, P1, P2, P3, and P4 were lower in cases of PFF (P < .001, P = .033, P = .008, P < .001, and P < .001, respectively). Additionally, the stem design was also statistically associated with PFF (P < .001). Multivariate logistic regression revealed that advanced age, higher BMI, osteoporosis, stem design, lower CFI, higher CBR, higher CCR, lower P1, lower P2, lower P3, and lower P4 were the risk factors of PFF (P < .001, P < .001, P < .001, P < .001, P < .001, P = .010, P < .001, P = .002, P < .001, P < .001, and P = .007, respectively). The ranked importance of the risk factors for PFF was P3, CFI, osteoporosis, CBR, age, P4, P1, stem design, CCR, BMI, and P2. CONCLUSIONS: Lower P3, lower CFI, osteoporosis, higher CBR, advanced age, lower P4, lower P1, stem design, higher CCR, higher BMI, and lower P2 increased the risk of PFF.

4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(3): 906-910, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-38926987

RESUMEN

OBJECTIVE: To investigate the role of levofloxacin combined with recombinant human granulocyte colony-stimulating factor (G-CSF) or only G-CSF supportive therapy in preventing infection in autologous hematopoietic stem cell transplantation(ASCT), and to analyze the length of hospital stay, hospitalization cost and post-transplant survival of the patients. METHODS: A retrospective analysis was performed in the patients with hematological malignancies who accepted ASCT at our hospital from January 2012 to July 2022, the febrile neutropenia, the incidence of bacterial infection and the use rate of intravenous antibiotics in the levofloxacin+G-CSF group and only G-CSF support group during ASCT were observed. The length of hospital stay, total cost during hospitalization and survival after 90 days of transplantation between the two groups were compared. RESULTS: A total of 102 cases were included in this study, including 57 cases of multiple myeloma, 36 cases of acute leukaemia, 7 cases of lymphoma, 3 cases of myelodysplastic syndrome, 1 case of light chain amyloidosis, and 1 case of POEMS syndrome. 47 patients received levofloxacin+ G-CSF antibacterial prophylaxis, and 55 patients received G-CSF supportive therapy. In the levofloxacin+ G-CSF group, 40 cases (85.11%) developed febrile neutropenia, and 13 cases (27.66%) were confirmed as bacterial infection. In the G-CSF group, 44 cases (80.00%) developed febrile neutropenia, and 16 cases (29.09%) were bacterial infection. There was no statistically significant difference in the incidence of febrile neutropenia and bacterial infection between the two groups (χ2=0.46,P =0.50; χ2=0.03,P =0.87). The use rate of intravenous antibiotics in the levofloxacin+ G-CSF group was 85.11% (40/47), which was not statistically different from 85.45% (47/55) in the G-CSF group (χ2=0.04,P =0.84). The detection rates of levofloxacin-resistant bacteria in the levofloxacin+ G-CSF group and G-CSF group were 8.57% (3/35) and 21.43% (6/28), respectively, with no statistical difference (χ2=0.65, P >0.05). The median length and median cost of hospitalization in the levofloxacin+ G-CSF group and G-CSF group were 25 d vs 22 d and 78 216.24 yuan vs 80 724.38 yuan, with no statistically significant differences ( t =3.00,P =0.09; t =0.94,P =0.09). Within 90 days after transplantation, two cases (4.26%) died in the levofloxacin+ G-CSF group and one case (1.82%) died in the G-CSF group, with no statistically significant difference between the two groups (χ2=0.53,P =0.47). CONCLUSION: Application of levofloxacin+ G-CSF showed no significant benefit compared to G-CSF support for the prevention of bacterial infections during ASCT.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos , Trasplante de Células Madre Hematopoyéticas , Levofloxacino , Trasplante Autólogo , Humanos , Estudios Retrospectivos , Infecciones Bacterianas/prevención & control , Antibacterianos , Masculino
6.
Comput Methods Programs Biomed ; 248: 108108, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38461712

RESUMEN

BACKGROUND: The existing face matching method requires a point cloud to be drawn on the real face for registration, which results in low registration accuracy due to the irregular deformation of the patient's skin that makes the point cloud have many outlier points. METHODS: This work proposes a non-contact pose estimation method based on similarity aspect graph hierarchical optimization. The proposed method constructs a distance-weighted and triangular-constrained similarity measure to describe the similarity between views by automatically identifying the 2D and 3D feature points of the face. A mutual similarity clustering method is proposed to construct a hierarchical aspect graph with 3D pose as nodes. A Monte Carlo tree search strategy is used to search the hierarchical aspect graph for determining the optimal pose of the facial 3D model, so as to realize the accurate registration of the facial 3D model and the real face. RESULTS: The proposed method was used to conduct accuracy verification experiments on the phantoms and volunteers, which were compared with four advanced pose calibration methods. The proposed method obtained average fusion errors of 1.13 ± 0.20 mm and 0.92 ± 0.08 mm in head phantom and volunteer experiments, respectively, which exhibits the best fusion performance among all comparison methods. CONCLUSIONS: Our experiments proved the effectiveness of the proposed pose estimation method in facial augmented reality.


Asunto(s)
Algoritmos , Realidad Aumentada , Humanos , Imagenología Tridimensional/métodos
7.
Langenbecks Arch Surg ; 409(1): 97, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38488934

RESUMEN

BACKGROUND: This study was recruited to compare the efficacy and safety of radiotherapy (RT) and transarterial chemoembolization (TACE) as postoperative adjuvant therapy after narrow-margin hepatectomy in hepatocellular carcinoma (HCC) patients. METHODS: This single-center prospective randomized study was conducted in the Cancer Hospital, Guang Xi Medical University, Nanning. A total of 72 patients who received treatment in this hospital between August 2017 and July 2019 were included and randomly allocated to TACE group (n = 48) and RT group (n = 24). Next, overall survival (OS) and progression-free survival (PFS) rates, recurrence patterns, financial burden, and safety were evaluated. RESULTS: The difference between the RT and TACE groups was not significant in one-, three-, and five-year OS (87.5%, 79.0%, and 62.5% vs. 93.8%, 75.9%, and 63.4%, respectively, P = 0.071) and PFS rates (79.0%, 54.2%, and 22.6% vs. 75.0%, 47.9%, and 32.6%, respectively, P = 0.071). Compared to the TACE group, the RT group had significantly lower intrahepatic recurrence rate (20.8% vs. 52.1%, P = 0.011), higher extrahepatic recurrence rate (37.5% vs. 14.6%, P = 0.034), and no marginal and diffuse recurrences (0% vs. 16.7%, P < 0.05). The mean overall treatment cost was higher (¥62,550.59 ± 4397.27 vs. ¥40,732.56 ± 9210.54, P < 0.01), the hospital stay (15.1 ± 3.7 vs. 11.8 ± 4.1 days, P < 0.01) was longer, and the overall treatment stay (13.3 ± 5.3 vs. 41.29 ± 12.4 days, P < 0.01) was shorter in the TACE group than in the RT group. Besides, both groups did not exhibit significant differences in the frequency and severity of adverse events. CONCLUSION: Both adjuvant TACE and RT can better the OS and PFS of patients with HCC. However, RT has a significantly better performance than TACE in terms of improving intrahepatic recurrence rate, treatment cost and hospital stay.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/cirugía , Hepatectomía , Estudios Prospectivos , Quimioembolización Terapéutica/efectos adversos , Resultado del Tratamiento , Estudios Retrospectivos
8.
Adv Mater ; 36(28): e2402239, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38519452

RESUMEN

In this work, a distinctive "metal-ion organic hybrid interface" (MOHI) between polyimide (PI) and calcium niobate (CNO) nanosheets is designed. The metal ions in the MOHI can achieve atomic-level matching not only with the inorganic CNO, but also with the PI chains, forming uniform and strong chemical bonds. These results are demonstrated by experiment and theory calculations. Significantly, the MOHI reduces the free volume and introduces deep traps across the filler-matrix interfacial area, thus suppressing the electric field distortion in PI-based composite dielectrics. Consequently, PI-based dielectric containing the MOHI exhibits excellent energy storage performance. The energy storage densities (Ue) of the composite dielectric reach 9.42 J cm-3 and 4.75 J cm-3 with energy storage efficiency (η) of 90% at 25 °C and 150 °C respectively, which are 2.6 and 11.6 times higher than those of pure PI. This study provides new ideas for polymer-based composite dielectrics in high energy storage.

9.
RSC Adv ; 14(12): 8240-8250, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38482069

RESUMEN

Prostate-specific antigen (PSA) serves as a critical biomarker for the early detection and continuous monitoring of prostate cancer. However, commercial PSA detection methods primarily rely on antigen-antibody interactions, leading to issues such as high costs, stringent storage requirements, and potential cross-reactivity due to PSA variant sequence homology. This study is dedicated to the precise design and synthesis of molecular entities tailored for binding with PSA. By employing a million-level virtual screening to obtain potential PSA compounds and effectively guiding the synthesis using machine learning methods, the resulting lead compounds exhibit significantly improved binding affinity compared to those developed before by researchers using high-throughput screening for PSA, substantially reducing screening and development costs. Unlike antibody detection, the design of these small molecules offers promising avenues for advancing prostate cancer diagnostics. Furthermore, this study establishes a systematic framework for the rapid development of customized ligands that precisely target specific protein entities.

10.
Anatol J Cardiol ; 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38327189

RESUMEN

BACKGROUND: Computed tomography (CT) image integration is of limited use in left ventricular (LV) ablation due to inadequate accuracy of registration. The current study aimed to investigate the accuracy and feasibility of extra-cavity LV image registration via the coronary cusp. METHODS: Consecutive patients were enrolled as the validation group (n = 41) and feasibility group (n = 48). After extra-cavity registration via the aortic root, the LV anatomy derived from CT image was activated and moved into real space. Accuracy of LV anatomy via this registration method was verified by intracardiac echocardiography reconstruction in the validation group and tested further in the feasibility group via measuring the location differences (<3 mm) and volume difference (<8 mL). RESULTS: In validation group, the LV volume of CT image and ICE map were comparable (113.6 ± 15.5 mL vs. 109.0 ± 15.3 mL, P =.27), and the location difference was 3.1 ± 1.1 mm at LV summit, 1.8 ± 0.9 mm at the free wall, and 1.8 ± 0.7 mm at the LV apex. There was a mean of 2.9 ± 1.2 mm and 3.0 ± 1.0 mm length difference in anterior PM and posterior PM, the position difference of the PM's base was 2.8 ± 0.9 mm for anterior PM and 2.2 ± 0.9 mm for posterior PM. In feasibility group, the distance differences of LV summit, LV septum, LV apex, and LV free averaged 1.8 ± 0.8 mm, 1.5 ± 0.7 mm, 1.4 ± 0.6 mm, 1.3 ± 0.7 mm, respectively. Compared with validation group, acute success (100% vs. 96.5%, P =.51), complications rate (4.9% vs. 2.0%, P = 0.59) and fluoroscopic time (1.6 ± 1.1 vs. 1.9 ± 1.6 minutes, P =.30) exhibited no significant difference, but was significantly reduced with procedure time (74.5 ± 8.1 vs. 61.2 ± 9.5 minutes, P <.001) with CT image registration only. CONCLUSION: LV mapping and ablation could be successfully achieved by extra-cavity registration via coronary cusp without needing positions within LV beforehand.

11.
Sci Adv ; 10(5): eadi7284, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38295161

RESUMEN

The end-Permian mass extinction was the most severe ecological event during the Phanerozoic and has long been presumed contemporaneous across terrestrial and marine realms with global environmental deterioration triggered by the Siberian Traps Large Igneous Province. We present high-precision zircon U-Pb geochronology by the chemical abrasion-isotope dilution-thermal ionization mass spectrometry technique on tuffs from terrestrial to transitional coastal settings in Southwest China, which reveals a protracted collapse of the Cathaysian rainforest beginning after the onset of the end-Permian marine extinction. Integrated with high-resolution geochronology from coeval successions, our results suggest that the terrestrial extinction occurred diachronously with latitude, beginning at high latitudes during the late Changhsingian and progressing to the tropics by the early Induan, spanning a duration of nearly 1 million years. This latitudinal age gradient may have been related to variations in surface warming with more degraded environmental conditions at higher latitudes contributing to higher extinction rates.

12.
Med Phys ; 51(1): 363-377, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37431603

RESUMEN

PURPOSE: This work proposes a robot-assisted augmented reality (AR) surgical navigation system for mandibular reconstruction. The system accurately superimposes the preoperative osteotomy plan of the mandible and fibula into a real scene. It assists the doctor in osteotomy quickly and safely under the guidance of the robotic arm. METHODS: The proposed system mainly consists of two modules: the AR guidance module of the mandible and fibula and the robot navigation module. In the AR guidance module, we propose an AR calibration method based on the spatial registration of the image tracking marker to superimpose the virtual models of the mandible and fibula into the real scene. In the robot navigation module, the posture of the robotic arm is first calibrated under the tracking of the optical tracking system. The robotic arm can then be positioned at the planned osteotomy after the registration of the computed tomography image and the patient position. The combined guidance of AR and robotic arm can enhance the safety and precision of the surgery. RESULTS: The effectiveness of the proposed system was quantitatively assessed on cadavers. In the AR guidance module, osteotomies of the mandible and fibula achieved mean errors of 1.61 ± 0.62 and 1.08 ± 0.28 mm, respectively. The mean reconstruction error of the mandible was 1.36 ± 0.22 mm. In the AR-robot guidance module, the mean osteotomy errors of the mandible and fibula were 1.47 ± 0.46 and 0.98 ± 0.24 mm, respectively. The mean reconstruction error of the mandible was 1.20 ± 0.36 mm. CONCLUSIONS: The cadaveric experiments of 12 fibulas and six mandibles demonstrate the proposed system's effectiveness and potential clinical value in reconstructing the mandibular defect with a free fibular flap.


Asunto(s)
Realidad Aumentada , Colgajos Tisulares Libres , Reconstrucción Mandibular , Robótica , Cirugía Asistida por Computador , Humanos , Reconstrucción Mandibular/métodos , Cirugía Asistida por Computador/métodos , Colgajos Tisulares Libres/cirugía , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía
14.
J Chem Inf Model ; 63(24): 7669-7675, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38061777

RESUMEN

Generating new molecules with the desired physical or chemical properties is the key challenge of computational material design. Deep learning techniques are being actively applied in the field of data-driven material informatics and provide a promising way to accelerate the discovery of innovative materials. In this work, we utilize an invertible graph generative model to generate hypothetical promising high-temperature polymer dielectrics. A molecular graph generative model based on the invertible normalizing flow is trained on a data set containing 250k polymer molecular graphs (mostly generated by an RNN-based generative model) to learn the invertible transformations between latent distributions and molecular graph structures. When generating molecular graphs, a sample vector is drawn from the latent space, and then an adjacency tensor and node attribute matrix are generated through two invertible flows in two steps and assembled into a molecular graph. The model has the merits of exact likelihood training and an efficient one-shot generation process. The learned latent space is used to generate polymers with a high glass-transition temperature (Tg) and a wide band gap (Eg) for the application of high-temperature energy storage film capacitors. This work contributes to the efficient design of high-temperature polymer dielectrics by using deep generative models.


Asunto(s)
Polímeros , Temperatura , Modelos Moleculares , Probabilidad
15.
Sci Rep ; 13(1): 19930, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37968566

RESUMEN

To research the magnetic field and mechanical characteristics of the permanent magnet governor, the static magnetic field of the sector permanent magnet is analyzed by the molecular current method in the permanent magnet governor. The magnetic flux distribution is acquired at any spatial position. Comparing the analytical value with the simulation value, the results show that they are basically consistent. Based on the analytical formula, the influence of the radial position, radial length, thickness, and pole number on the magnetic induction intensity of the permanent magnet governor is studied. Thus, it provides the theoretical reference for the structural optimized design. At the same time, a test bench was set up to measure the magnetic induction intensity. The calculation and experimental results show that the magnetic induction strength of the permanent magnet is increased by 27.5%, the axial component of the air gap flux density is increased by 14.3%, and the permanent magnet material is reduced by 7.84%.

16.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(5): 1556-1562, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-37846716

RESUMEN

OBJECTIVE: To analyze the pathogenic bacterial spectrum, drug resistance, and risk factors associated with multidrug-resistant bacterial infection and mortality in patients with hematologic diseases complicated by bloodstream infections, so as to provide reference for rational drug use and improving prognosis. METHODS: Positive blood culture specimens of patients with hematologic diseases in two Class A tertiary hospitals of Shanxi province from January 2019 to December 2021 were retrospectively analyzed. Pathogen distribution, drug resistance and outcomes of patients with bloodstream infection were investigated, then the multivariate logistic analysis was performed to analyze the risk factors of multidrug-resistant bacterial infection and factors affecting prognosis. RESULTS: 203 strains of pathogens were identified, mainly Gram-negative bacteria (GNB) (69.46%, 141/203), of which Escherichia coli (E.coli) had the highest incidence (41.13%, 58/141), followed by Klebsiella pneumoniae (20.57%, 29/141) and Pseudomonas aeruginosa (12.77%, 18/141). Extended-spectrum beta-lactamase (ESBL)-producing E.coli and Klebsiella pneumoniae were 46.55% (27/58) and 37.93% (11/29), respectively. Carbapenem-resistant Gram-negative bacteria accounted for 10.64% (15/141). And Gram-positive bacteria accounted for 27.59% (56/203), Staphylococcus epidermidis, Streptococcus pneumoniae, and Staphylococcus aureus were the most frequently isolated pathogen among Gram-positive bacteria (14.29%, 12.50% and 10.71%, respectively), of which methicillin-resistant Staphylococcus aureus accounted for 33.33% (2/6), coagulase-negative staphylococci accounted for 87.50% (7/8), without vancomycin- or linezolid-resistant strain. Additionally, fungi accounted for 2.95% (6/203), all of which were Candida. Multidrug-resistant Gram-negative bacteria (MDR-GNB) accounted for 53.90% (76/141). Duration of neutropenia >14 days was a risk factor for developing MDR-GNB infection. The 30-day all-cause mortality was 10.84%. Multivariate logistic regression analysis showed that the significant independent risk factors for mortality were age≥60 years (P <0.01, OR =5.85, 95% CI: 1.80-19.07) and use of vasopressor drugs (P <0.01, OR =5.89, 95% CI: 1.83-18.94). CONCLUSION: The pathogenic bacteria of bloodstream infection in patients with hematological diseases are widely distributed, and the detection rate of multidrug-resistant bacteria is high. The clinicians should choose suitable antibiotics according to the results of bacterial culture and antibiotic susceptibility test.


Asunto(s)
Bacteriemia , Farmacorresistencia Bacteriana , Enfermedades Hematológicas , Staphylococcus aureus Resistente a Meticilina , Sepsis , Humanos , Persona de Mediana Edad , Bacteriemia/etiología , Bacteriemia/microbiología , Bacteriemia/mortalidad , Bacterias/aislamiento & purificación , Resistencia a Medicamentos , Bacterias Gramnegativas , Enfermedades Hematológicas/complicaciones , Estudios Retrospectivos , Factores de Riesgo , Sepsis/etiología , Sepsis/microbiología , Sepsis/mortalidad
17.
Phys Rev Lett ; 131(10): 103002, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37739370

RESUMEN

We investigate the 2^{3}S_{1}-2^{3}P_{J} (J=0, 1, 2) transitions in ^{6}Li^{+} using the optical Ramsey technique and achieve the most precise values of the hyperfine splittings of the 2^{3}S_{1} and 2^{3}P_{J} states, with smallest uncertainty of about 10 kHz. The present results reduce the uncertainties of previous experiments by a factor of 5 for the 2^{3}S_{1} state and a factor of 50 for the 2^{3}P_{J} states, and are in better agreement with theoretical values. Combining our measured hyperfine intervals of the 2^{3}S_{1} state with the latest quantum electrodynamic (QED) calculations, the improved Zemach radius of the ^{6}Li nucleus is determined to be 2.44(2) fm, with the uncertainty entirely due to the uncalculated QED effects of order mα^{7}. The result is in sharp disagreement with the value 3.71(16) fm determined from simple models of the nuclear charge and magnetization distribution. We call for a more definitive nuclear physics value of the ^{6}Li Zemach radius.

18.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1806-1816, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37694464

RESUMEN

Forest canopy closure (FCC) is an important parameter to evaluate forest resources and biodiversity. Using multi-source remote sensing collaborative means to achieve regional forest canopy closure inversion with low cost and high-precision is a research hotspot. Taking ICESat-2/ATLAS data as the main information source and combined with data of 54 measured plots, we estimated FCC value by the Bayesian optimization (BO) algorithm improved random forest (RF), K-nearest neighbor (KNN), and gradient boosting regression tree (GBRT) model at footprint-scale. Combined with multi-source remote sensing image Sentinel-1/2 and terrain factors, we estimated the regional-scale FCC value of Shangri-La in the northwest Yunnan based on deep neural network (DNN) optimized by BO algorithm. The results showed that six characteristic parameters (percentage of tree canopy, standard deviation of relative height of photons at the top of the canopy, minimum canopy height, difference between 98% canopy height and median canopy height in the segment, number of top canopy photons, apparent surface reflectance) out of the 50 parameters that were extracted from ATLAS lidar footprint had higher contribution rate after RF characteristic variable optimization, which could be used as model variable for footprint-scale remote sensing estimation. Among BO-RF, BO-KNN, and BO-GBRT models, the FCC results estimated by the BO-GBRT model were the best at footprint-scale. The coefficient of determination (R2) was 0.65, the root mean square error (RMSE) was 0.10, the mean absolute residual (RS) was 0.079, and the prediction accuracy (P) was 0.792 for leave-one-out cross validation. It could be used as the FCC estimation model of 74808 ATLAS footprints for forest in the study area. We used the ATLAS footprint-scale FCC value of forest as the large sample data of the regional-scale BO-DNN model and combined with multi-source remote sensing factors to estimate FCC in the study area, the accuracy of the 10-fold cross-validation BO-DNN model was R2=0.47, RMSE=0.22, P=0.558. The mean values of FCC in the study area estimated by BO-DNN model and ordinary Kriging (OK) interpolation were 0.46 and 0.52, respectively, and the values mainly distributed in 0.3-0.6, accounting for 77.8% and 81.4%, respectively. The FCC efficiency obtained directly by the OK interpolation method was higher (R2=0.26), but the prediction accuracy was significantly lower than the BO-DNN model (R2=0.49). The FCC high value was distributed from northwest to southeast in the study area, and the northern and southeastern regions were the main distribution areas of high and low FCC values, respectively. It had certain advantages to estimate mountain area FCC based on ICESat-2/ATLAS high-density footprint, and the estimation results of small sample data at footprint-scale could be used as large sample data of deep learning model at region-scale, which would provide a reference for the low-cost and high-precision to FCC estimation on the footprint-scale up to the extrapolated regional-scale.


Asunto(s)
Algoritmos , Tecnología de Sensores Remotos , Teorema de Bayes , China , Biodiversidad
19.
Parasit Vectors ; 16(1): 287, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37587480

RESUMEN

BACKGROUND: Cryptocaryon irritans, a common parasite in tropical and subtropical marine teleost fish, has caused serious harm to the marine aquaculture industry. Honokiol was proven to induce C. irritans tomont cytoplasm shrinkage and death in our previous study, but the mechanism by which it works remains unknown. METHODS: In this study, the changes of apoptotic morphology and apoptotic ratio were detected by microscopic observation and AnnexinV-FITC/PI staining. The effects of honokiol on intracellular calcium ([Ca2+]i) concentration, mitochondrial membrane potential (ΔΨm), reactive oxygen species (ROS), quantity of DNA fragmentations (QDF) and caspase activities were detected by Fluo-3 staining, JC-1 staining, DCFH-DA staining, Tunel method and caspase activity assay kit. The effects of honokiol on mRNA expression levels of 61 apoptosis-related genes in tomonts of C. irritans were detected by real-time PCR. RESULTS: The results of the study on the effects of honokiol concentration on C. irritans tomont apoptosis-like death showed that the highest levels of prophase apoptosis-like death rate (PADR), [Ca2+]i concentration, ROS, the activities of caspase-3/9 and the lowest necrosis ratio (NER) were obtained at a concentration of 1 µg/ml, which was considered the most suitable for inducing C. irritans tomont apoptosis-like death. When C. irritans tomonts were treated with 1 µg/ml honokiol, the [Ca2+]i concentration began to increase significantly at 1 h. Following this, the ROS, QDF and activities of caspase-3/9 began to increase significantly, and the ΔΨm began to decrease significantly at 2 h; the highest PADR was obtained at 4 h. The mRNA expression of 14 genes was significantly upregulated during honokiol treatment. Of these genes, itpr2, capn1, mc, actg1, actb, parp2, traf2 and fos were enriched in the pathway related to apoptosis induced by endoplasmic reticulum (ER) stress. CONCLUSIONS: This article shows that honokiol can induce C. irritans tomont apoptosis-like death. These results suggest that honokiol may disrupt [Ca2+]i homeostasis in ER and then induce C. irritans tomont apoptosis-like death by caspase cascade or mitochondrial pathway, which might represent a novel therapeutic intervention for C. irritans infection.


Asunto(s)
Apoptosis , Caspasas , Animales , Caspasa 3/genética , Especies Reactivas de Oxígeno , ARN Mensajero
20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(4): 1199-1204, 2023 Aug.
Artículo en Chino | MEDLINE | ID: mdl-37551498

RESUMEN

OBJECTIVE: To explore the clinical characteristics of hospitalized patients with hematologic diseases complicated with carbapenem-resistant organisms (CRO) infection and analyze the risk factors of 30-day all-cause mortality. METHODS: The clinical data and laboratory test data of 77 hospitalized patients with hematologic diseases complicated with CRO infection in department of hematology of the Third Hospital of Shanxi Medical University from January 2015 to December 2020 were retrospectively analysed, the risk factors of 30-day all-cause mortality after CRO infection were analyzed by multivariate logistic regression. RESULTS: Among the total of 77 patients with hematologic diseases complicated with CRO infection, 29 died and 48 survived within 30 days of infection, with a case fatality rate of 37.66%. A total of 93 strains of CRO were isolated from these patients, of which Acinetobacter baumannii had the highest detection rate (25.81%, 24/93), followed by Pseudomonas aeruginosa (18.28%, 17/93). The lung was the most common site of CRO infection. The detected pathogens were highly resistant to carbapenems, and 64.52% (60/93) of the pathogens were resistant to imipenem with minimum inhibitory concentration (MIC)≥16 µg/ml. The results of the univariate analysis showed that albumin concentration <25 g/L (P =0.048), serum creatinine concentration≥120 µmol/L (P =0.023), age-adjusted Charlson comorbidity index (ACCI) (P =0.037) and primary treatments (supportive treatment, immunosuppressive therapy, chemotherapy, HSCT) (P =0.048) were significantly associated with 30-day all-cause mortality after infection. The results of multivariate logistic regression analysis showed that when CRO infection confirmed, albumin concentration <25 g/L (P =0.014, OR=6.171), serum creatinine concentration≥120 µmol/L (P =0.009, OR=10.867) were independent risk factors for 30-day mortality of patients with hematologic diseases complicated with CRO infection. CONCLUSION: The mortality rate of CRO-infected patients with hematologic diseases is high. The detected pathogenic bacteria are highly resistant to imipenem. The albumin concentration <25 g/L and the serum creatinine concentration≥ 120 µmol/L at diagnosis of CRO infection were independent risk factors for 30-day mortality of the patients with hematologic diseases.


Asunto(s)
Carbapenémicos , Enfermedades Hematológicas , Humanos , Carbapenémicos/farmacología , Estudios Retrospectivos , Creatinina , Factores de Riesgo , Imipenem , Albúminas
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