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1.
Pediatr Res ; 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39147906

RESUMEN

BACKGROUND: Rapidly progressive necrotizing enterocolitis (RP-NEC) is a particular subtype of NEC known for its rapid progression and high mortality rate. The objective of this study was to establish a predictive model for RP-NEC. METHODS: This was a retrospective single-center cohort study. Patients were newborn infants with NEC (Bell's stage ≥ IIB) admitted from January 1, 2016 to December 31, 2023. The primary outcome was RP-NEC defined as the need for surgical intervention and/or death within 48 hours of the onset of NEC. RESULTS: Totally 334 newborn infants were included, among which 82 (24.6%) were RP-NEC cases with a gestation age 34.1 (31.0, 37.0) weeks and birth weight 2100 (1413, 2800) g. Plasma sodium <135 mmol/L, C-reactive protein ≥10 mg/L, platelet count <100 × 109/L, lymphocyte count <1.5 × 109/L, pH <7.2 in blood gas, and ascites at NEC onset were identified as independent risk factors for RP-NEC. The model established presented an AUC value of 0.983 (95% CI 0.97-0.99). The calibration curve for validation was applied revealing a slope close to unity while the Hosmer-Lemeshow test yielded χ2 = 2.550 (p = 0.636). CONCLUSION: The predictive model established on the above 6 items of RP-NEC is highly promising. IMPACT: Currently, there is a paucity of research on this specific type of severe necrotizing enterocolitis (NEC) characterized by rapid progression. Our study was to investigate the risk factors associated with surgical intervention and/or death within 48 hours following onset in infants with NEC, establish a predictive model for infants with rapidly progressive NEC. The new data presented in this study was the ROC curve combining the above factors as well as hyponatremia.

2.
Pediatr Cardiol ; 45(4): 814-820, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38374353

RESUMEN

Neonatal arrhythmias are significant contributors to infant mortality. Timely diagnosis and treatment are essential for neonates with non-benign arrhythmias to avoid severe complications, and ongoing treatment and follow-up are sometimes needed. The main objective of this study will be to understand the incidence and demographic characteristics of arrhythmias in hospitalized neonates in China and the related factors of outcomes. A secondary objective will be to establish the first follow-up system for neonatal arrhythmias in China. The medical burdens of neonatal arrhythmias in China will also be investigated. The data from the Futang Research Center of Pediatric Development (FRCPD) database between January 2016 and December 2021 were obtained. Newborns admitted to member hospitals with a discharge diagnosis of "neonatal arrhythmia" (ICD-10 code P29.151) or "arrhythmia" (ICD-10 code I49.904) were included. The medical record information was collected and classified into two groups: heart failure and non-heart failure. The differences between the two groups and independent risk factors for neonatal arrhythmias complicated with heart failure were analyzed. In addition, a follow-up study of patients discharged from Beijing Children's Hospital was conducted to evaluate their outcomes at the age of 3 years old. Factors influencing hospitalization costs were analyzed using rank-sum tests and multiple linear regression. It is anticipated that the study findings will provide new and comprehensive data on the health needs of neonatal arrhythmias in China. The study will establish the first follow-up system for neonatal arrhythmias in China. This study will help reduce the burden of patients and their families as well as the society.


Asunto(s)
Insuficiencia Cardíaca , Hospitales , Lactante , Humanos , Recién Nacido , Niño , Preescolar , Estudios de Seguimiento , Estudios Retrospectivos , China/epidemiología , Arritmias Cardíacas/epidemiología , Arritmias Cardíacas/terapia
3.
Virol J ; 20(1): 248, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891594

RESUMEN

BACKGROUND: Sepsis is a systemic inflammatory response syndrome caused by severe infection in children, but cases of sepsis associated with human parainfluenza virus (HPIV) have been rarely reported in newborns. CASE PRESENTATION: We report a case of HPIV-3 positive full-term newborn admitted to the Neonatal Intensive Care Unit of Beijing Children's Hospital due to hematuria, gloomy spirit, inactivity and loss of appetite for 6 h. He had septic shock when he arrived the Accident & Emergency Department requiring immediate intubation and mechanical ventilation. Intravenous antibiotics were started. He had completely negative response to all anti-shock treatments including fluid resuscitation and vasopressor supports, and died 14 h later. Viral nucleic acid detection and metagenomic next-generation sequencing (mNGS) analyses of nasopharyngeal aspirate and blood specimens verified an HPIV-3 infection, with negative bacterial culture results. The HPIV-3 strain detected in this patient was subtyped as HPIV C3a, and two unreported amino acid mutations were found in the HN protein region. CONCLUSION: The patient had a severe infection associated with HPIV-3, which was the cause of sepsis and septic shock. This study showed the diagnostic value of mNGS in etiological diagnosis, especially in severe neonatal case.


Asunto(s)
Infecciones del Sistema Respiratorio , Choque Séptico , Niño , Masculino , Humanos , Recién Nacido , Virus de la Parainfluenza 3 Humana/genética , Choque Séptico/diagnóstico , Viremia , Mutación , Virus de la Parainfluenza 2 Humana
4.
Small ; 18(41): e2204005, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36094790

RESUMEN

Catalysis is regarded as an effective strategy to fundamentally increase sulfur utilization, accelerating the kinetics of the transformation between lithium polysulfides (LiPSs) and lithium sulfide (Li2 S) on a substrate. However, the intermodulation of catalysts and sulfur species is elusive, which is limited to the comprehensive analysis of electrochemical performance in the dynamic reaction process. Herein, cobalt nanoparticles loaded on MXene nanosheets (Co/Ti2 C) are selected as sulfur hosts and the representative catalyst. By combining ex situ electrochemical results and interfacial structural chemical monitoring, the catalysis process of Co/Ti2 C toward LiPSs conversion is revealed, and the outstanding performance originates from the optimization of chemical adsorption, catalytic activity, and lithium-ion transfer behaviors, which is based on electronic/ion modulation and sufficient interfaces among catalysts and electrolyte. This work can guide the construction of electronic modulation at triple-phase interface catalysis to overcome the shuttle effect and facilitate sulfur redox kinetics in Li-S batteries.

5.
Chemistry ; 28(38): e202200622, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35491397

RESUMEN

A novel electrochemically assisted cycloaddition process is proposed, in which highly efficient coupling of CO2 with styrene oxide (SO) can be achieved to form styrene carbonate (SC) as a high-value-added product. A series of Cu catalysts with different morphologies and chemical states were fabricated on carbon paper (CP) by using in-situ electrodeposition, and the sample with nano-dendrimer structure was found to exhibit a relatively high activity of 74.8 % SC yield with 92.7 % SO conversion under gentle reaction conditions, thus showing its potential for practical applications. The relatively high electrochemically active surface area and charge transfer ability of dendrimer-like Cu benefited the electrochemical reaction. In particular, the Cu2+ species that were formed in situ during the reaction played a vital role in enhancing the activity and selectivity of the proposed Cu/CP hybrid catalyst. Cu2+ atoms served as active sites that can not only electrochemically activate CO2 but also facilitate the ring opening of SO. Mechanistic analysis suggested that the reaction followed electrochemical and liquid-phase heterogeneous paths, which provide a new green and sustainable route for efficient utilization of CO2 resources for fine chemical electrosynthesis.

6.
Eur J Pediatr ; 181(8): 3005-3011, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35616731

RESUMEN

Neonatal transport scoring systems can assess severity before and after transport, improve transport efficiency, and predict the occurrence of critical illness. The aim of this study was to compare four neonatal transport scoring methods to predict mortality risk and clinical utility within the first week after transportation. This was a single-center retrospective cohort study. All patients were full-term, out-born neonates. Each patient was assessed by the Transport Risk Index of Physiologic Stability (TRIPS), Mortality Index for Neonatal Transportation (MINT), Transport-Related Mortality Score (TREMS), and Neonatal Critical Illness Score (NCIS) scoring methods. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) for each method were compared for their utility in predicting mortality risk within the 1st week after admission. In total, 368 full-term infants were included (368/770, 47.8% of all transported infants). Within the 1st week after admission, five infants (1.36%, 5/368) died while receiving advanced life support and full treatment, and 24 infants (6.52%, 24/368) died soon after they were discharged against medical advice. The areas under the curve (AUCs) for the MINT, TRIPS, TREMS, and NCIS for the prediction of mortality were 0.822, 0.827, 0.643, and 0.731, respectively (all p < 0.05). However, the clinical net benefits for the MINT and TRIPS were far superior than those for the NCIS and TREMS. CONCLUSION: It was concluded that the TRIPS and MINT might be more suitable for the prediction of mortality in full-term, out-born neonates in the neonatal intensive care unit (NICU) within the 1st week after transportation. WHAT IS KNOWN: • Neonatal transport scores can assess not only the mortality risk during transportation but also the mortality risk of critically ill newborns after admission to the NICU. • The effectiveness of neonatal transport scores in predicting mortality risk is different. WHAT IS NEW: • Our data indicate that the diagnostic efficacy of the MINT, TRIPS, and NCIS in the prediction of full-term infant mortality was high. • The TRIPS and MINT scores had better clinical utility and could be used to predict mortality within the 1st week after transportation in full-term out-born neonates.


Asunto(s)
Enfermedad Crítica , Proyectos de Investigación , Humanos , Lactante , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Curva ROC , Estudios Retrospectivos
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(12): 1245-1250, 2020 Dec.
Artículo en Zh | MEDLINE | ID: mdl-33327992

RESUMEN

OBJECTIVE: To investigate the incidence rate of infectious diseases during hospitalization in late preterm infants in Beijing, China, as well as the risk factors for infectious diseases and the effect of breastfeeding on the development of infectious diseases. METHODS: Related data were collected from the late preterm infants who were hospitalized in the neonatal wards of 25 hospitals in Beijing, China, from October 23, 2015 to October 30, 2017. According to the feeding pattern, they were divided into a breastfeeding group and a formula feeding group. The two groups were compared in terms of general status and incidence rate of infectious diseases. A multivariate logistic regression analysis was used to investigate the risk factors for infectious diseases. RESULTS: A total of 1 576 late preterm infants were enrolled, with 153 infants in the breastfeeding group and 1 423 in the formula feeding group. Of all infants, 484 (30.71%) experienced infectious diseases. The breastfeeding group had a significantly lower incidence rate of infectious diseases than the formula feeding group (22.88% vs 31.55%, P=0.033). The multivariate logistic regression analysis showed that breastfeeding was an independent protective factor against infectious diseases (OR=0.534, P=0.004), while male sex, premature rupture of membranes, gestational diabetes mellitus, and asphyxia were risk factors for infectious diseases (OR=1.328, 5.386, 1.535, and 2.353 respectively, P < 0.05). CONCLUSIONS: Breastfeeding can significantly reduce the incidence of infectious diseases and is a protective factor against infectious diseases in late preterm infants. Breastfeeding should therefore be actively promoted for late preterm infants during hospitalization.


Asunto(s)
Lactancia Materna , Enfermedades Transmisibles , Hospitalización , Recien Nacido Prematuro , Beijing/epidemiología , China/epidemiología , Enfermedades Transmisibles/epidemiología , Femenino , Hospitales , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Embarazo
8.
Artículo en Inglés | MEDLINE | ID: mdl-30509939

RESUMEN

Amoxicillin is widely used to treat bacterial infections in neonates. However, considerable intercenter variability in dosage regimens of antibiotics exists in clinical practice. The pharmacokinetics of amoxicillin has been described in only a few preterm neonates. Thus, we aimed to evaluate the population pharmacokinetics of amoxicillin through a large sample size covering the entire age range of neonates and young infants and to establish evidence-based dosage regimens based on developmental pharmacokinetics-pharmacodynamics. This is a prospective, multicenter, pharmacokinetic study using an opportunistic sampling design. Amoxicillin plasma concentrations were determined using high-performance liquid chromatography. Population pharmacokinetic analysis was performed using NONMEM. A total of 224 pharmacokinetic samples from 187 newborns (postmenstrual age range, 28.4 to 46.3 weeks) were available for analysis. A two-compartment model with first-order elimination was used to describe population pharmacokinetics. Covariate analysis showed that current weight, postnatal age, and gestational age were significant covariates. The final model was further validated for predictive performance in an independent cohort of patients. Monte Carlo simulation demonstrated that for early-onset sepsis, the currently used dosage regimen (25 mg/kg twice daily [BID]) resulted in 99.0% of premature neonates and 87.3% of term neonates achieving the pharmacodynamic target (percent time above MIC), using a MIC breakpoint of 1 mg/liter. For late-onset sepsis, 86.1% of premature neonates treated with 25 mg/kg three times a day (TID) and 79.0% of term neonates receiving 25 mg/kg four times a day (QID) reached the pharmacodynamic target, using a MIC breakpoint of 2 mg/liter. The population pharmacokinetics of amoxicillin was assessed in neonates and young infants. A dosage regimen was established based on developmental pharmacokinetics-pharmacodynamics.


Asunto(s)
Amoxicilina/administración & dosificación , Amoxicilina/farmacocinética , Antibacterianos/administración & dosificación , Antibacterianos/farmacocinética , Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Pruebas de Sensibilidad Microbiana , Modelos Teóricos , Estudios Prospectivos
9.
Plant Cell Rep ; 36(6): 829-842, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28238071

RESUMEN

KEY MESSAGE: γ-Decalactone accumulation in peach mesocarp was highly correlated with ACX enzyme activity and natural PpACX1 content. Adding the purified recombinant PpACX1 induced γ-decalactone biosynthesis in cultured mesocarp discs in vitro. Previous gene expression studies have implied that acyl coenzyme A oxidase (ACX) is related to lactones synthesis, the characteristic aroma compounds of peach. Here, we analysed the correlation between γ-decalactone content and ACX enzyme activity in mesocarp of five different types of fully ripe peach varieties. Furthermore, 'Hu Jing Mi Lu' ('HJ') and 'Feng Hua Yu Lu' ('YL'), which have strong aroma among them, at four ripening stages were selected to study the role of ACX in lactone biosynthesis. The result showed that γ-decalactone was the most abundant lactone compound. γ-Decalactone accumulation was highly correlated with ACX enzyme activity. Mass spectrometry (MS) showed that PpACX1 was the most abundant PpACX protein in fully ripe mesocarp of cv. 'HJ'. To further elucidate the function of the PpACX1 protein, the PpACX1 gene was heterologously expressed in a bacterial system and characterized in vitro. MS identification gave the molecular weight of the recombinant PpACX1 as 94.44 kDa and the coverage rate of the peptide segments was 47.3%. In cultured mesocarp discs in vitro, adding the purified recombinant PpACX1 and C16-CoA substrate induced the expected γ-decalactone biosynthesis. Using a sandwich ELISA based on mixed mono- and polyclonal antibodies against recombinant PpACX1, PpACX1 content in mesocarp was found to be highly correlated with γ-decalactone accumulation in mesocarp of five fully ripe varieties and four ripening stages of 'HJ' and 'YL'. This study revealed the vital function of PpACX1 in γ-decalactone biosynthesis in peach fruit.


Asunto(s)
Acil-CoA Oxidasa/metabolismo , Frutas/enzimología , Frutas/metabolismo , Lactonas/metabolismo , Proteínas de Plantas/metabolismo , Prunus persica/enzimología , Prunus persica/metabolismo , Acil-CoA Oxidasa/genética , Frutas/genética , Proteínas de Plantas/genética , Prunus persica/genética
10.
ScientificWorldJournal ; 2014: 832850, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25243229

RESUMEN

Nonactivated and activated biochars have been successfully prepared by bananas at different thermotreatment temperatures. The activated biochar generated at 900°C (Biochar-act900) exhibited improved oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) performances in alkaline media, in terms of the onset potential and generated current density. Rotating disk electron result shows that the average of 2.65 electrons per oxygen molecule was transferred during ORR of Biochar-act900. The highest power density of 528.2 mW/m(2) and the maximum stable voltage of 0.47 V were obtained by employing Biochar-act900 as cathode catalyst, which is comparable to the Pt/C cathode. Owning to these advantages, it is expected that the banana-derived biochar cathode can find application in microbial fuel cell systems.


Asunto(s)
Fuentes de Energía Bioeléctrica , Carbón Orgánico/aislamiento & purificación , Carbón Orgánico/metabolismo , Musa , Catálisis , Electrodos
11.
Phys Ther Sport ; 65: 1-6, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37976905

RESUMEN

OBJECTIVES: This study aimed to determine the effect of foot strike patterns and cadences in male runners with patellofemoral pain (PFP). DESIGN: Cross-sectional study. SETTING: Biomechanics lab. METHODS: 20 male runners with PFP were instructed to randomly complete six running conditions (three cadence conditions in rearfoot strike pattern (RFS) or forefoot strike (FFS)) under a preferred running speed. MAIN OUTCOME MEASURES: The primary outcomes were peak knee joint and moment, and secondary outcomes were patellofemoral joint stress. RESULTS: Running with increased cadence has a lower flexion angle (P = 0.027, η2 = 0.45), lower extension moment (P = 0.011, η2 = 0.29), lower internal rotation moment (P = 0.040, η2 = 0.17), lower patellofemoral stress (P = 0.029, η2 = 0.52) than preferred cadence. FFS running performed significantly lower flexion angle (P = 0.003, η2 = 0.39), lower extension moment (P < 0.001, η2 = 0.91), lower adduction moment (P = 0.020, η2 = 0.25) lower patellofemoral stress (P < 0.001, η2 = 0.81) than RFS running for all cadence. CONCLUSIONS: Preliminary findings provide new perspectives for male runners with PFP to unload patellofemoral joint stress in managing PFP through the combination of the FFS pattern and increased cadence.


Asunto(s)
Articulación Patelofemoral , Síndrome de Dolor Patelofemoral , Masculino , Humanos , Estudios Transversales , Pie , Articulación de la Rodilla , Fenómenos Biomecánicos , Marcha
12.
Nanomicro Lett ; 16(1): 266, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133318

RESUMEN

Fluorine owing to its inherently high electronegativity exhibits charge delocalization and ion dissociation capabilities; as a result, there has been an influx of research studies focused on the utilization of fluorides to optimize solid electrolyte interfaces and provide dynamic protection of electrodes to regulate the reaction and function performance of batteries. Nonetheless, the shuttle effect and the sluggish redox reaction kinetics emphasize the potential bottlenecks of lithium-sulfur batteries. Whether fluorine modulation regulate the reaction process of Li-S chemistry? Here, the TiOF/Ti3C2 MXene nanoribbons with a tailored F distribution were constructed via an NH4F fluorinated method. Relying on in situ characterizations and electrochemical analysis, the F activates the catalysis function of Ti metal atoms in the consecutive redox reaction. The positive charge of Ti metal sites is increased due to the formation of O-Ti-F bonds based on the Lewis acid-base mechanism, which contributes to the adsorption of polysulfides, provides more nucleation sites and promotes the cleavage of S-S bonds. This facilitates the deposition of Li2S at lower overpotentials. Additionally, fluorine has the capacity to capture electrons originating from Li2S dissolution due to charge compensation mechanisms. The fluorine modulation strategy holds the promise of guiding the construction of fluorine-based catalysts and facilitating the seamless integration of multiple consecutive heterogeneous catalytic processes.

13.
Chronobiol Int ; 41(6): 789-801, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38738753

RESUMEN

This study aims to explore the relationship between the circadian rhythms of critically ill patients and the incidence of Status Epilepticus (SE), and to develop a predictive model based on circadian rhythm indicators and clinical factors. We conducted a diurnal rhythm analysis of vital sign data from 4413 patients, discovering significant differences in the circadian rhythms of body temperature, blood oxygen saturation, and heart rate between the SE and non-SE groups, which were correlated with the incidence of SE. We also employed various machine learning algorithms to identify the ten most significant variables and developed a predictive model with strong performance and clinical applicability. Our research provides a new perspective and methodology for the study of biological rhythms in critically ill patients, offering new evidence and tools for the prevention and treatment of SE. Our findings are consistent or similar to some in the literature, while differing from or supplementing others. We observed significant differences in the vital signs of epileptic patients at different times of the day across various diagnostic time groups, reflecting the regulatory effects of circadian rhythms. We suggest heightened monitoring and intervention of vital signs in critically ill patients, especially during late night to early morning hours, to reduce the risk of SE and provide more personalized treatment plans.


Asunto(s)
Ritmo Circadiano , Enfermedad Crítica , Estado Epiléptico , Humanos , Ritmo Circadiano/fisiología , Estado Epiléptico/fisiopatología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Adulto , Temperatura Corporal/fisiología , Pacientes Internos , Frecuencia Cardíaca/fisiología
14.
Sci Total Environ ; 925: 171656, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38490416

RESUMEN

Toxic metal(loid)s contamination of paddy soil is a nonnegligible issue and threatens food safety considering that it is transmitted via the soil-plant system. Applying remediation agents could effectively inhibit the soil available toxic metal(loid)s and reduce their accumulation in rice. To comprehensively quantify how remediation agents impact the accumulation of Cd/Pb/As in rice, rice growth and yield, the accumulation of available Cd/Pb/As in paddy soil, and soil characteristics, 50 peer-reviewed publications were selected for meta-analysis. Overall, the application of remediation agents exhibited significant positive effects on rice plant length (ES = 0.05, CI = 0.01-0.08), yield (ES = 0.20, CI = 0.13-0.27), peroxidase (ES = 0.56, CI = 0.18-0.31), photosynthetic rate (ES = 0.47, CI = 0.34-0.61), and respiration rate (ES = 0.68, CI = 0.47-0.88). Among the different types of remediation agents, biochar was the most effective in controlling the accumulation of Cd/Pb/As in all portions of rice, and was also superior in inhibiting the accumulation of Pb in rice grains (ES = -0.59, 95 % CI = -1.04-0.13). This study offers an essential contribution for the remediation strategies of toxic metal(loid)s contaminated paddy fields.


Asunto(s)
Oryza , Contaminantes del Suelo , Suelo , Cadmio/análisis , Plomo , Contaminantes del Suelo/análisis
15.
ACS Appl Mater Interfaces ; 15(35): 42104-42111, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37615113

RESUMEN

The interface structure of supported catalysts plays a significant role in the strong metal-support interactions (SMSI). However, it remains limited on interpreting interface structures, thus affecting the understanding of SMSI origin and impact on catalytic performance. Herein, electronic energy loss spectroscopy was adopted to characterize the interface microstructures of Pt/TiO2 materials. After high-temperature reduction processing, it was observed that the coating on the surface of the Pt metal particles was TiOx. Then, based on Gaussian function fitting, an effective and valid method was established for quantitative analysis on Ti L edge loss spectrum. This method allowed us to accurately determine the stoichiometric number of TiOx phases. In order to probe the classical phenomenon of strong metal-support interactions in more detail, we also discussed and analyzed the origin of TiOx and its effect on the electronic structure of the material using density functional theory calculations. The structure of surfaces and interfaces as well as the chemical evolution of supported catalysts on a microscale have been revealed, thereby providing a new analysis method and research perspectives for the future study of metal-support interactions.

16.
PLoS One ; 18(1): e0280477, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36689415

RESUMEN

BACKGROUND: Patellofemoral pain (PFP) is a common overuse injury among runners. It is not only a hindrance to the runner's training, but also to the runner's quality of life. PFP runners may strategize different running strategies to reduce patellofemoral joint stress, release pain, and improve function. PURPOSE: This study aimed to determine the changes in joint coordination and variability under combinations of foot strike pattern and cadence for runners with patellofemoral pain. METHODS: Twenty male runners with PFP performed six running strategies which were two strike patterns named forefoot (FFS) and rearfoot (RFS) accompanied by three running cadences named slow10%, normal, and fast10%. A modified vector coding technique and circular statistics were respectively used to identify the coordination pattern and variability between hip sagittal-knee frontal (HsKf), hip sagittal-knee sagittal (HsKs) and knee transverse-ankle frontal (KtAf) during stance phase. Coordination patterns which were conformed with anatomical motion pattern was classified as mechanically sound, and the distribution frequency of each coordination pattern was quantified. RESULTS: Switching to FFS, the HsKf couples (p < 0.001, ES = 1.34) and the HsKs couples (p = 0.001, ES = 0.82) displayed significantly greater frequency in mechanically unsound coordination pattern during the initial stance phase. The effect of increasing running cadence on RFS displayed significantly greater frequency in mechanically unsound hip dominancy (p = 0.042, ES = 0.65) and knee dominancy (p = 0.05, ES = 0.70) coordination patterns for HsKf couples as well as for HsKs couples (p = 0.023, ES = 0.86) during the initial stance phase. Combined with FFS and fast10% cadence, HsKs couples showed more hip-dominated mechanical sound coordination pattern (p = 0.002, ES = 1.25). Further, altering footstrike pattern and cadence failed to change the coordination variability. CONCLUSIONS: Changing running cadence (± 10%) combined with transfer strike pattern from RFS to FFS could not increase the distribution frequency in mechanically sound coordination patterns and change coordination variability for PFP runners.


Asunto(s)
Síndrome de Dolor Patelofemoral , Masculino , Humanos , Calidad de Vida , Marcha , Fenómenos Biomecánicos , Extremidad Inferior
17.
Acta Bioeng Biomech ; 25(1): 27-34, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38314549

RESUMEN

PURPOSE: Cutting maneuvers are important actions in multidirectional sports but associated with noncontact anterior cruciate ligament (ACL) injuries. This study aimed to investigate the effect of different foot strike patterns and cutting angles on knee kinematics and kinetics. METHODS: Twenty healthy male team sports athletes performed cuts with maximum speed at three angles (45, 90 and 135°) with different foot strike patterns (rearfoot strike [RFS] and forefoot strike [FFS]). A three-dimensional motion capture system combined with a force plate was used to collect makers trajectory and ground reaction force (GRF). Vertical GRF, and knee joint angles and moments were compared among these cutting tasks. RESULTS: Regardless of foot strike patterns, increased knee flexion angle, knee valgus moment, and knee internal rotation moment were observed during cutting to sharper angles (p < 0.001). At 90 and 135°, the FFS condition remained in a varus position and showed lower knee flexion moment than the RFS condition ( p ≤ 0.004). However, no significant differences in knee kinematic and kinetic variables were found between foot strike patterns during cutting to 45°. CONCLUSIONS: These findings suggest that sharper cutting angles potentially increase the risk of ACL injury. Compared with the RFS pattern, the FFS pattern induces a slight knee varus angle and a lower knee flexion moment at sharper angles, which might further reduce the load placed on the knee.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Rodilla , Masculino , Humanos , Fenómenos Biomecánicos , Extremidad Inferior , Articulación de la Rodilla , Pie
18.
Nanoscale ; 15(11): 5327-5336, 2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36811914

RESUMEN

Lithium-sulfur (Li-S) batteries, as one of the new energy storage batteries, show immense potential due to their high theoretical specific capacity and theoretical energy density. However, there are still some problems to be solved, among which the shuttle effect of lithium polysulfides is one extremely serious issue with respect to the industrial application of Li-S batteries. Rational design of electrode materials with effective catalytic conversion ability is an effective route to accelerate the conversion of lithium polysulfides (LiPSs). Herein, considering the adsorption and catalysis of LiPSs, CoOx nanoparticles (NPs) loaded on carbon sphere composites (CoOx/CS) were designed and constructed as cathode materials. The CoOx NPs obtained, with ultralow weight ratio and uniform distribution, consist of CoO, Co3O4, and metallic Co. The polar CoO and Co3O4 enable chemical adsorption towards LiPSs through Co-S coordination, and the conductive metallic Co can improve electronic conductivity and reduce impedance, which is beneficial for ion diffusion at the cathode. Based on these synergistic effects, the CoOx/CS electrode exhibits accelerated redox kinetics and enhanced catalytic activity for conversion of LiPSs. Consequently, the CoOx/CS cathode delivers improved cycling performance, with an initial capacity of 980.8 mA h g-1 at 0.1C and a reversible specific capacity of 408.4 mA h g-1 after 200 cycles, along with enhanced rate performance. This work provides a facile route to construct cobalt-based catalytic electrodes for Li-S batteries, and promotes understanding of the LiPSs conversion mechanism.

19.
Huan Jing Ke Xue ; 44(9): 5125-5134, 2023 Sep 08.
Artículo en Zh | MEDLINE | ID: mdl-37699830

RESUMEN

Soil erosion is the main driving force of soil organic carbon (SOC) loss and plays an important role in the global carbon cycle. It is helpful to understand the mechanism of SOC loss under soil erosion by evaluating the main driving factors of SOC loss under soil erosion and their influence degree. Therefore, based on 24 cases published in domestic and foreign journals from 2007 to 2021, this study investigated the effects of soil erosion on SOC loss in China under different climatic factors (climate types, rainfall, and rainfall intensity) and soil factors (soil types, bulk density, and aggregate size) by using Meta-analysis. The results showed that:① compared with that under no erosion disturbance, the SOC content under erosion decreased significantly (overall decreased 16.0%), showing obvious negative response characteristics. ② Under the erosion background, the negative response degree of SOC to different factors was as follows:rainfall intensity (65.0%)>mean annual rainfall (24.3%)>soil types (21.4%)>bulk density (20.2%)>aggregate size (16.5%)>climate types (9.1%). ③ Principal component analysis showed that climate was the dominant factor affecting SOC loss, and rainfall intensity was again shown to be the key factor. In this study, the characteristics and influencing factors of SOC loss under soil erosion in China were analyzed, which provided theoretical reference for the systematic understanding of the role of soil erosion in the carbon cycle.

20.
Pediatr Investig ; 7(4): 239-246, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38050540

RESUMEN

Importance: Central line-associated bloodstream infection (CLABSI) is one of the most serious complications of central venous access devices. Reducing the risk of CLABSI is of utmost significance in efforts to improve neonatal mortality rates and enhance long-term prognosis. Objective: To determine the dwell time and incidence of CLABSI of umbilical venous catheterization (UVC) for preterm infants in China. Methods: Preterm infants with UVC admitted to 44 tertiary neonatal intensive care units in 24 provinces in China were enrolled. Study period was from November 2019 to August 2021. The end point of observations was 48 h after umbilical venous (UV) catheter removal. The primary outcomes were dwell time of UV catheter and UVC-associated CLABSI. Data between infants with UV catheter dwell time ≤7 days and >7 days, and with birth weight (BW) ≤1000 g and >1000 g were compared. Results: In total, 2172 neonates were enrolled (gestational age 30.0 ± 2.4 weeks, BW 1258.5 ± 392.8 g). The median UV catheter dwell time was 7 (6-10) days. The incidence of UVC-associated CLABSI was 3.03/1000 UV catheter days. For infants with UV catheter dwell time ≤7 days and >7 days, the UVC-associated CLABSI incidence was 3.71 and 2.65 per 1000 UV catheter days, respectively, P = 0.23. For infants with UVC dwell times of 3-6, 7-12, and 13-15 days, the UVC-associated CLABSI rates were 0.14%, 0.68%, and 2.48% (P < 0.01). The Kaplan-Meier plot of UV catheter dwell time to CLABSI showed no difference between infants with BW ≤1000 g and >1000 g (P = 0.60). Interpretation: The median dwell time of UV catheter was 7 days, and the incidence of UVC-associated CLABSI was 3.03/1000 catheter days in China. The daily risk of UVC-associated CLABSI and other complications increased with the dwell time.

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