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1.
Small ; 19(32): e2205644, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37078836

RESUMEN

Nanocomposites with hierarchical pore structure hold great potentials for applications in the field of microwave-absorbing materials because of their lightweight and high-efficiency absorption properties. Herein, M-type barium ferrite (BaM) with ordered mesoporous structure (M-BaM) is prepared via a sol-gel process enhanced by mixed anionic and cationic surfactants. The surface area of M-BaM is enhanced almost ten times compared with BaM together with 40% reflection loss enhancing. Then M-BaM compounded with nitrogen-doped reduced graphene oxide (MBG) is synthesized via hydrothermal reaction in which the reduction and nitrogen doping of graphene oxide (GO) in situ occur simultaneously. Interestingly, the mesoporous structure is able to provide opportunity for reductant to enter the bulk M-BaM reducing its Fe3+ to Fe2+ and further forms Fe3 O4 . It requires an optimal balance among the remained mesopores in MBG, formed Fe3 O4 , and CN in nitrogen-doped graphene (N-RGO) for optimizing impedance matching and greatly increasing multiple reflections/interfacial polarization. MBG-2 (GO:M-BaM = 1:10) achieves the minimum reflection loss of -62.6 dB with an effective bandwidth of 4.2 GHz at an ultra-thin thickness of 1.4 mm. In addition, the marriage of mesoporous structure of M-BaM and light mass of graphene reduces the density of MBG.

2.
Metab Eng ; 75: 119-130, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36503050

RESUMEN

The hybrid cybernetic model (HCM) approach is a dynamic modeling framework that integrates enzyme synthesis and activity regulation. It has been widely applied in bioreaction engineering, particularly in the simulation of microbial growth in different mixtures of carbon sources. In a HCM, the metabolic network is decomposed into elementary flux modes (EFMs), whereby the network can be reduced into a few pathways by yield analysis. However, applying the HCM approach on conventional genome-scale metabolic models (GEMs) is still a challenge due to the high computational demands. Here, we present a HCM strategy that introduced an optimized yield analysis algorithm (opt-yield-FBA) to simulate metabolic dynamics at the genome-scale without the need for EFMs calculation. The opt-yield-FBA is a flux-balance analysis (FBA) based method that can calculate optimal yield solutions and yield space for GEM. With the opt-yield-FBA algorithm, the HCM strategy can be applied to get the yield spaces and avoid the computational burden of EFMs, and it can therefore be applied for developing dynamic models for genome-scale metabolic networks. Here, we illustrate the strategy by applying the concept to simulate the dynamics of microbial communities.


Asunto(s)
Genoma , Redes y Vías Metabólicas , Redes y Vías Metabólicas/genética , Algoritmos , Simulación por Computador , Modelos Biológicos , Análisis de Flujos Metabólicos
3.
New Phytol ; 240(6): 2498-2512, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37846026

RESUMEN

Supporting food security while maintaining ecosystem sustainability is one of the most important global challenges for humanity. Optimization of cropping systems is expected to promote the ecosystem services of agroecosystems. Yet, how and why cropping system influences the trade-offs between economic profitability and multiple ecosystem services remain poorly understood. We investigate the influence of six cropping systems on trade-offs between economic profitability and multiple ecosystem services after considering 36 agricultural ecosystem properties using field experiment data from 2020 to 2022. We show that designing cropping system is a critical tool to closing the gap between ecosystem sustainability and commercial profitability. Cropping system with three harvests within 2 yr had higher performance in overall ecosystem multiple services through enhancement of supporting, regulating, and economic performance without compromising provisioning compared with four other systems. These systems diminished the trade-off among multiple services, resulting in a 'win-win' situation for economics and multiple services. By contrast, the monoculture and double cropping systems lead to a strong trade-off between pairwise services including ecosystem health and profitability. Our work illustrates the substantial potential of rotation systems with three harvests within 2 yr in enforcing ecosystem services and closing the trade-offs among multiple agricultural ecosystem services.


Asunto(s)
Agricultura , Ecosistema , Salud Ambiental , Conservación de los Recursos Naturales/métodos
4.
Crit Rev Food Sci Nutr ; 63(19): 3788-3802, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34694187

RESUMEN

Chocolate is a non-Newtonian substance, and such substance has different viscosities at different shear rates. Rheological evaluations have become indispensable instruments for characterizing final chocolate, forecasting product efficiency and consumer acceptance. During production, the different steps depend on a well-defined viscosity and yield stress. Furthermore, the characteristics of the final chocolate (the surface and mouth-feel) are directly related to the chocolate's viscous behavior. There is a demand for better understanding the variables affecting chocolates flow behavior. Current research realized great insight into the chocolate flow behavior in different processes such as refining, conching, and tempering. Also, the influence of formulation and particle characteristics on flow behavior of the intermediate product and the final product were discussed. Each stage of the production process: mixing, refining, conching and tempering involves modifications of macroscopic characteristics of the chocolate ingredients thus affecting the rheological attributes of the final product. Particle size distribution and ingredient composition play substantial roles in shaping its flow behavior and sensory perception. The rheological properties of chocolate provide substantial information for food scientists to improve and optimize their products and manufacturing processes. Nowadays, a thorough understanding of chocolate flow behavior is a necessity for food scientists and industry.


Asunto(s)
Cacao , Chocolate , Sensación
5.
Environ Res ; 219: 115064, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36549230

RESUMEN

The key to enhancing the efficacy of bioremediation of hydrocarbon-contaminated soil is the precise and highly efficient screening of functional isolates. Low screening effectiveness, narrow screening range and an unstable structure of the constructed microflora during bioremediation are the shortcomings of the traditional shaking culture (TSC) method. To improve the secondary screening of isolates and microflora implemented for alkane degradation, this work evaluated the characterization relationship between bacterial function and enzyme activity and devised an enzyme activity assay (EAA) method. The results indicated a substantial positive correlation (r = 0.97) between 24 candidate isolates and their whole enzymes, proving that whole enzyme activity properly reflects the metabolic functions of microorganisms. The functional analysis of the isolates demonstrated that the EAA method in conjunction with microbial abundance and metabolite determination could broaden the screening range of functional isolates, including aliphatic acid-metabolizing isolates (isolates H4 and H7) and aliphatic acid-sensitive isolates (isolate H2) with n-hexadecane degradation ability. The EAA method also guided the construction of functional microflora and optimized the mode of application using combinations of alkane-degrading bacteria and aliphatic acid-degrading bacteria successively (e.g., F1+H7+H7). The combinations maintained a high abundance of functional isolates and stable α diversity and community composition throughout the experiment, which contributed to more advanced alkane degradation and mineralization ability (p < 0.01). Assuming a workload of 100 tests, the screening efficiency of the EAA method is more than 16 times that of the TSC method, and the greater the quantity of isolates, the higher the screening efficiency, enabling high-throughput screening. In conclusion, the EAA method has a broad-spectrum, accurate and highly efficient screening ability for functional isolates and microflora, which can provide intensive technical support for the development of bioremediation materials and the application of bioremediation technology.


Asunto(s)
Petróleo , Contaminantes del Suelo , Biodegradación Ambiental , Petróleo/metabolismo , Petróleo/microbiología , Contaminantes del Suelo/análisis , Microbiología del Suelo , Hidrocarburos , Alcanos/metabolismo , Suelo
6.
Sensors (Basel) ; 23(4)2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36850643

RESUMEN

California is the world's biggest producer and exporter of almonds. Currently, the sweeping of almonds during the harvest creates a significant amount of dust, causing air pollution in the neighboring urban areas. A low-dust sweeping system was designed to reduce the dust during the sweeping of almonds in the orchard. The system includes a feedback control system to control the sweeper brushes' height and their angular velocity by adjusting the forward velocity of the harvester and the brushes' rotational speeds to avoid any extra overlapping sweeping, which increases dust generation. The governing kinematic equations for sweepers' angular velocity and vehicle forward speed were derived. The feedback controllers for synchronizing these speeds were designed to optimize brush/dust contact to minimize dust generation. The sweepers' height controller was also designed to stabilize the gap between the brushes and the orchard floor and track the road trajectory. Controllers were simulated and tuned for a fast response for agricultural applications with less than a second response delay. Results showed that the designed system has acceptable performance and generates low amounts of dust within the acceptable range of California ambient air quality standards.

7.
Molecules ; 28(6)2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36985633

RESUMEN

The main component of phosphogypsum (PG) is CaSO4·2H2O. PG contains a few impurities, heavy metals, and radioisotopes, which limit the use of PG and pose a danger to the environment. In this study, under the excitation of a sodium hydroxide solution, the rheological properties of a paste with granulated blast-furnace slag (GGBS) and PG treated with ultrasonic water washing were investigated. Experimental results showed that the ratio of GGBS to PG and the amount of sodium hydroxide solution significantly affect the density and viscosity of the paste, but the effect patterns of both are different. The maximum viscosity was 498 mPa·s when the ratio of GGBS to PG was 4:1. When the ratio changed from 3:2 to 1:4, the viscosity of the paste gradually decreased by 15.5%, 32.1%, 36.1%, and 46.8%, respectively. In contrast, the ratio of GGBS to PG had a greater effect on the viscosity than the amount of sodium hydroxide solution in terms of the standard consistency water consumption, viscosity, and water release ratio. The larger the PG ratio, the smaller the density, viscosity, and water release ratio of the paste. The variation in the ratio of GGBS to PG had a significant effect on the water film thickness of the paste, demonstrating that the larger the PG mixture, the larger the water film thickness of the paste, which reached 1.122 µm, 2.31 times the minimum water film thickness of the paste. At the same time, the water film thickness of the paste was negatively correlated with the water consumption of the standard consistency, viscosity, and water release ratio, and was positively correlated with the fluidity.

8.
Am J Obstet Gynecol ; 226(3): 366-378, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35026129

RESUMEN

This study reviewed the literature about the diagnosis, antepartum surveillance, and time of delivery of fetuses suspected to be small for gestational age or growth restricted. Several guidelines have been issued by major professional organizations, including the International Society of Ultrasound in Obstetrics and Gynecology and the Society for Maternal-Fetal Medicine. The differences in recommendations, in particular about Doppler velocimetry of the ductus venosus and middle cerebral artery, have created confusion among clinicians, and this review has intended to clarify and highlight the available evidence that is pertinent to clinical management. A fetus who is small for gestational age is frequently defined as one with an estimated fetal weight of <10th percentile. This condition has been considered syndromic and has been frequently attributed to fetal growth restriction, a constitutionally small fetus, congenital infections, chromosomal abnormalities, or genetic conditions. Small for gestational age is not synonymous with fetal growth restriction, which is defined by deceleration of fetal growth determined by a change in fetal growth velocity. An abnormal umbilical artery Doppler pulsatility index reflects an increased impedance to flow in the umbilical circulation and is considered to be an indicator of placental disease. The combined finding of an estimated fetal weight of <10th percentile and abnormal umbilical artery Doppler velocimetry has been widely accepted as indicative of fetal growth restriction. Clinical studies have shown that the gestational age at diagnosis can be used to subclassify suspected fetal growth restriction into early and late, depending on whether the condition is diagnosed before or after 32 weeks of gestation. The early type is associated with umbilical artery Doppler abnormalities, whereas the late type is often associated with a low pulsatility index in the middle cerebral artery. A large randomized clinical trial indicated that in the context of early suspected fetal growth restriction, the combination of computerized cardiotocography and fetal ductus venosus Doppler improves outcomes, such that 95% of surviving infants have a normal neurodevelopmental outcome at 2 years of age. A low middle cerebral artery pulsatility index is associated with an adverse perinatal outcome in late fetal growth restriction; however, there is no evidence supporting its use to determine the time of delivery. Nonetheless, an abnormality in middle cerebral artery Doppler could be valuable to increase the surveillance of the fetus at risk. We propose that fetal size, growth rate, uteroplacental Doppler indices, cardiotocography, and maternal conditions (ie, hypertension) according to gestational age are important factors in optimizing the outcome of suspected fetal growth restriction.


Asunto(s)
Retardo del Crecimiento Fetal , Peso Fetal , Femenino , Retardo del Crecimiento Fetal/diagnóstico por imagen , Retardo del Crecimiento Fetal/terapia , Edad Gestacional , Humanos , Lactante , Placenta , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Ultrasonografía Doppler , Ultrasonografía Prenatal , Arterias Umbilicales/diagnóstico por imagen
9.
Molecules ; 27(13)2022 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-35807337

RESUMEN

Rice blast is a serious threat to rice yield. Breeding disease-resistant varieties is one of the most economical and effective ways to prevent damage from rice blast. The traditional identification of resistant rice seeds has some shortcoming, such as long possession time, high cost and complex operation. The purpose of this study was to develop an optimal prediction model for determining resistant rice seeds using Ranman spectroscopy. First, the support vector machine (SVM), BP neural network (BP) and probabilistic neural network (PNN) models were initially established on the original spectral data. Second, due to the recognition accuracy of the Raw-SVM model, the running time was fast. The support vector machine model was selected for optimization, and four improved support vector machine models (ABC-SVM (artificial bee colony algorithm, ABC), IABC-SVM (improving the artificial bee colony algorithm, IABC), GSA-SVM (gravity search algorithm, GSA) and GWO-SVM (gray wolf algorithm, GWO)) were used to identify resistant rice seeds. The difference in modeling accuracy and running time between the improved support vector machine model established in feature wavelengths and full wavelengths (200-3202 cm-1) was compared. Finally, five spectral preproccessing algorithms, Savitzky-Golay 1-Der (SGD), Savitzky-Golay Smoothing (SGS), baseline (Base), multivariate scatter correction (MSC) and standard normal variable (SNV), were used to preprocess the original spectra. The random forest algorithm (RF) was used to extract the characteristic wavelengths. After different spectral preproccessing algorithms and the RF feature extraction, the improved support vector machine models were established. The results show that the recognition accuracy of the optimal IABC-SVM model based on the original data was 71%. Among the five spectral preproccessing algorithms, the SNV algorithm's accuracy was the best. The accuracy of the test set in the IABC-SVM model was 100%, and the running time was 13 s. After SNV algorithms and the RF feature extraction, the classification accuracy of the IABC-SVM model did not decrease, and the running time was shortened to 9 s. This demonstrates the feasibility and effectiveness of IABC in SVM parameter optimization, with higher prediction accuracy and better stability. Therefore, the improved support vector machine model based on Ranman spectroscopy can be applied to the fast and non-destructive identification of resistant rice seeds.


Asunto(s)
Espectroscopía Infrarroja Corta , Máquina de Vectores de Soporte , Algoritmos , Fitomejoramiento , Semillas/química
10.
J Sci Food Agric ; 102(10): 4238-4249, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35023570

RESUMEN

BACKGROUND: The agricultural production system is facing increasing demand pressure and environmental pressure. Green and efficient production methods are urgently needed in order to further enhance the yield of winter wheat and reduce the negative impact on the environment. Here, we analyzed the potential yield and yield gap of winter wheat in Shandong Province of China from 1981 to 2009. Meanwhile, we specified the effects of sowing time, irrigation and fertilization scheme, and variety characteristics on winter wheat. RESULTS: In the past 29 years, the yield gap in most areas of Shandong has become smaller, because the actual yield has increased and the potential yield has changed little under the background of climate change. In addition, it is found that delaying sowing date is beneficial to increase yield by helping winter wheat avoid adverse climate conditions. Also, an irrigation amount of 240 mm and nitrogen application amount of 180-210 kg ha-1 are best to maintain high yield, high resource utilization rate and low environmental pollution in this area. These suggested levels are lower than those currently used by many local farmers. Wheat varieties with longer grain-filling period and photoperiod response, higher grain-filling rate and grain weight were more adaptable to climate change. CONCLUSION: Improving agronomic management measures can significantly increase the yield of winter wheat and narrow the yield gap. This study can provide valuable information for improving the production potential of winter wheat, and for reducing the damage of agricultural activities to the environment. © 2022 Society of Chemical Industry.


Asunto(s)
Nitrógeno , Triticum , Riego Agrícola/métodos , Agricultura/métodos , China , Grano Comestible/química , Nitrógeno/análisis , Estaciones del Año
11.
Molecules ; 26(15)2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34361699

RESUMEN

A new series of laterally fluorinated mesomorphic compounds, namely 2-fluoro-4-((4-(alkyloxy)phenyl)diazenyl)phenyl 4-substitutedbenzoate (Inx) were prepared and evaluated for their mesophase behavior. The synthesized series constitutes five members that possess different terminally attached polar groups (X). Their molecular structures were confirmed by elemental analyses and both FT-IR and NMR spectroscopy. Examination of the prepared derivatives was conducted via experimental and theoretical tools. Mesomorphic investigations were carried by polarized optical microscopy (POM) and differential scanning calorimetry (DSC). DSC and POM measurements indicated that except for the un-substituted analogue, all other derivatives were purely nematogenic, possessing their nematic (N) mesophase enantiotropically. This is to say that insertions of terminal polar substituents on their mesogenic structures induced the N phase. In addition, the location of lateral and terminal polar moieties played a considerable role in achieving good thermal N stability. Computational calculations were investigated to determine the deduced optimized molecular structures. Theoretical data indicated that both size and polarity of the terminal substituent (X) have essential impact on the thermal parameters and optical properties of possible geometries.

12.
Entropy (Basel) ; 23(6)2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34073742

RESUMEN

Electric power frameworks become intensely loaded because of the expanded power demand, and as a result, the power system faces great power losses and fault currents. The integration of Distribution Generation (DG) units plays a key role in minimizing the load pressure on a power system. DGs are transmitted with a high fault current, which surpasses the evaluations of circuit breakers. This paper presents various DG units' optimal placement with Fault Current Limiters (FCLs) in different phases. The Improved Coyote Optimize Algorithm (ICOA) and Electrical Transient Analyzer Program (ETAP) are assessed for the proposed technique in terms of normal and faulty working status. Similarly, to enhance the efficiency of a distribution system, a fuzzy-based multi-objective mechanism is applied. The proposed method is employed on an IEEE 21-bus and 28-bus distribution system. The simulation analysis proved that the power losses and fault levels are reduced at an acceptable level.

13.
J Surg Oncol ; 121(3): 474-479, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31846095

RESUMEN

BACKGROUND: Patients with ruptured, perforated or fistulized (RPF) sarcomas commonly have issues such as sepsis and malnutrition and are usually unsuitable for oncologic resection in the emergency setting. We present our approach for managing a series of patients and the outcomes which were achieved with multidisciplinary care. METHODS: We reviewed records of patients referred to the section of sarcoma surgical oncology. Clinicopathologic factors, preoperative and operative interventions as well as short-term oncologic outcomes were assessed. RESULTS: Sixteen patients were identified between 1 January 1998 to 31 December 2018. Median age was 42.8 years. Histologies were; Gastrointestinal stromal tumors (7), desmoid (4), spindle cell tumor (2), dedifferentiated liposarcoma (2), and nonseminomatous germ cell tumor (1). Five patients had preoperative sepsis, 8 received antimicrobials, and 50% required hospitalization with a median stay of 21 days. Total parenteral nutrition was administered to 5 (31.3%) patients. Median tumor size and estimated blood loss were 13.1 cm and 350 mL respectively. No perioperative mortality occurred. Two patients have expired at a median follow-up of 16.1 months. CONCLUSION: Preoperative optimization, including the use of percutaneous drains, and antibiotics to control sepsis, where necessary, can lead to eventual oncologic resection with acceptable morbidity and no short-term mortality for patients with RPF sarcomas.


Asunto(s)
Neoplasias Gastrointestinales/cirugía , Tumores del Estroma Gastrointestinal/cirugía , Sarcoma/cirugía , Adulto , Anciano , Femenino , Fibromatosis Agresiva/patología , Fibromatosis Agresiva/cirugía , Neoplasias Gastrointestinales/patología , Tumores del Estroma Gastrointestinal/patología , Humanos , Liposarcoma/patología , Liposarcoma/cirugía , Masculino , Mesodermo/fisiología , Persona de Mediana Edad , Rotura Espontánea , Sarcoma/patología , Adulto Joven
14.
BMC Health Serv Res ; 20(1): 1052, 2020 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-33213453

RESUMEN

BACKGROUND: Physical activity (PA) is a well-established therapeutic modality for the maintenance and improvement of long-term health in cystic fibrosis (CF). Healthcare professionals (HCP) are considered credible and well-placed messengers for the delivery of PA advice. Limited research exists investigating the extent of PA prescription within CF care. This study aimed to identify Irish HCP i) knowledge and practice of, and ii) motivators and barriers to PA prescription, and iii) proposed strategies to optimize PA promotion and prescription in CF populations. METHODS: HCP from six designated CF centres in Ireland and members of the national physiotherapy CF clinical interest group were invited to participate. Following an expression of interest, each HCP (n = 81) received an email containing the plain language statement and link to the online survey. 48 HCP (physiotherapists n = 24, other n = 24) completed the 30-item investigator-developed survey, which included multiple choice single answer, matrix style and open-ended questions. RESULTS: Most HCP (81%) acknowledged that discussing PA with CF patients was part of their professional role. Almost all physiotherapists (95%) reported having sufficient knowledge regarding PA prescription, compared to 17% of other HCP. All physiotherapists reported discussing PA at every patient interaction, with 81% employing the current consensus guidelines, compared to 33 and 5% of other HCP, respectively. Among the most common barriers reported by HCP to recommending PA to their CF patients were; lack of motivation and compliance among patients to adhere to PA advice, limited availability of PA programmes to refer their patients to, limited time with patients during clinic visits and a lack of knowledge regarding PA prescription for CF care. Three-quarters of HCP reported a need to improve PA services for CF patients in Ireland. CONCLUSION: As people with CF are living longer, it is imperative that HCP are expanding their scope of practice to include discussions around PA at every patient visit. Formal educational opportunities in the form of continuing professional development programmes are warranted for CF HCP to optimize long-term patient management and outcomes. There is also a need to develop patient-centered and evidence-based PA programmes underpinned by theories of behaviour change to enhance motivation and compliance among CF patients.


Asunto(s)
Fibrosis Quística , Fibrosis Quística/terapia , Ejercicio Físico , Humanos , Irlanda , Lenguaje , Prescripciones
15.
Wiad Lek ; 73(5): 877-882, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32386362

RESUMEN

OBJECTIVE: The aim: Scientific substantiation of physiological-hygienic standards of motor activity of students of higher education institutions and ways of its optimization in the context of formation of an effective public health system. PATIENTS AND METHODS: Materials and methods: The criteria for physiological-hygienic assessment of students' motor activity were: the values of daily energy, the quantity of locomotions, the duration of dynamic component in daily budget of time. RESULTS: Results: The data of complex assessment of the modern students' motor activity studying in the institution of higher medical education showed its low level. At the same time the application of measures aimed at optimizing motor activity of students ensured an improvement (p<0.01-0.001) of the functional characteristics of the mobility and balance of nervous processes and index of coordination of movements. CONCLUSION: Conclusions: In the course of the researches the physiological-hygienic standards of motor activity of students are scientifically substantiated: values of daily energy consumption - 9000-11000 kJ in young women, 11500-13500 kJ in young men, the quantity of locomotions in the daily cycle - 14000-18000 steps and 15000-19000 steps respectively, the duration of dynamic component in daily budget of time - 130-180 min and 140-190 min respectively.


Asunto(s)
Salud Pública , Universidades , Femenino , Humanos , Masculino , Actividad Motora , Instituciones Académicas , Estudiantes
16.
Oncologist ; 24(2): 178-184, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30297386

RESUMEN

BACKGROUND: Zoledronic acid (ZA), a potent bisphosphonate used for treatment of bone metastasis, has high bone affinity. This post hoc analysis evaluated the effects of long-term treatment and reduction in dosing frequency of ZA on bone saturation. MATERIALS AND METHODS: Pharmacokinetic data from three independent studies, OPTIMIZE-2 (patients receiving ≥9 doses of bisphosphonates) and two phase I studies, CZOL4460503 and CZOL4460506 (patients who were bisphosphonate naïve/bisphosphonate free for ≥1 year after previous dosing), were pooled. Serial urine and plasma samples were used as surrogate markers to determine ZA plasma area under the curve (AUC) over 6 hours (AUC0-6h) and dose excreted in urine over 6 hours (urine0-6h). Potential relationships between the number of years for which patients had been treated previously at time of study entry and AUC0-6h or urine0-6h were analyzed graphically. RESULTS: Creatinine clearances for patients were similar across the three studies and at all time points analyzed. The levels of AUC0-6h ZA in plasma at week 0 in every (q) 4 and q12 weekly arms of OPTIMIZE-2 were 0.366 h × mg/L and 0.397 h × mg/L compared with 0.345 h × mg/L and 0.356 h × mg/L in CZOL4460503 and CZOL4460506, respectively. In OPTIMIZE-2, the AUC0-6h ZA plasma levels were the same (0.428 h × mg/L) at week 36 in both q4 and q12 arms. The levels of ZA urine0-6h at week 36 in OPTIMIZE-2 (q4 and q12 week arms), CZOL4460503, and CZOL4460506 were 36.6%, 30.8%, 26.5%, and 27.3%, respectively. CONCLUSION: Long-term ZA treatment may not impact bone saturation, and ZA dosing frequency does not seem to influence drug retention rates. IMPLICATIONS FOR PRACTICE: Zoledronic acid (ZA), used along with standard antineoplastic therapy to treat bone metastases associated with solid tumors and multiple myeloma, requires frequent (every 3-4 or every 12 weeks) long-term administration. This may result in bone saturation and subsequently lead to a higher risk of adverse events such as osteonecrosis of the jaw and atypical fractures. This post hoc analysis used surrogate markers to demonstrate that prolonged ZA administration does not cause bone saturation. Furthermore, reduction in ZA dosing frequency does not affect its retention level in bones over time. These findings will help in addressing clinicians' concerns regarding prolonged ZA administration.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Huesos/efectos de los fármacos , Ácido Zoledrónico/uso terapéutico , Conservadores de la Densidad Ósea/farmacología , Neoplasias Óseas/secundario , Femenino , Humanos , Metástasis de la Neoplasia , Ácido Zoledrónico/farmacocinética , Ácido Zoledrónico/farmacología
17.
Sensors (Basel) ; 19(24)2019 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-31861149

RESUMEN

Multi-input multi-output (MIMO) is usually defined as a radar system in which the transmit time and receive time, space and transform domain can be separated into multiple independent signals. Given the bandwidth and power constraints of the radar system, MIMO radar can improve its performance by optimize design transmit waveforms and receive filters, so as to achieve better performance in suppressing clutter and noise. In this paper, we cyclicly optimize the transmit waveform and receive filters, so as to maximize the output signal interference and noise ratio (SINR). From fixed pulse-to-pulse waveform to pulse-to-pulse waveform variations, we discuss the joint optimization under energy constraint, then extend it to optimizations under constant-envelope constraint and similarity constraint. Compared to optimization with fixed pulse-to-pulse waveform, the generalized optimization achieves higher output SINR and lower minimum detectable velocity (MDV), further improve the suppressing performance.

18.
Arch Virol ; 162(9): 2885-2889, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28501954

RESUMEN

The complete genome sequence of a new virus isolated from a longan (Dimocarpus longan Lour.) plant showing witches' broom syndrome was determined. The viral genome is composed of a monopartite single-stranded RNA of 9,428 nucleotides excluding the 3' poly(A) tail and contains one large single open reading frame encoding a polyprotein of 3086 amino acids. BLAST searches of protein databases showed that the encoded polyprotein has a maximum amino acid sequence identity of 35% (with 85% coverage) to that of the isolate Minnesota of rose yellow mosaic virus (RoYMV; family Potyviridae; genus not assigned). Molecular and phylogenetic analysis of the genome and encoded protein sequences showed that the identified virus has the general features that are characteristic of members of the family Potyviridae although it has extremely low sequence similarity to known members of the family Potyviridae. The name longan witches' broom-associated virus (LWBaV) is proposed for this new virus, which may be considered a member of a new genus in the family Potyviridae.


Asunto(s)
Genoma Viral , Potyviridae/genética , Potyviridae/aislamiento & purificación , Sapindaceae/virología , Filogenia
19.
J Am Acad Dermatol ; 86(3): e103-e104, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-32428612
20.
Pacing Clin Electrophysiol ; 40(8): 947-954, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28618036

RESUMEN

BACKGROUND: Electrophysiology procedures require fluoroscopic guidance, with the associated potentially adverse effects of ionizing radiation. Newer fluoroscopy systems have more features that enable dose-reduction strategies. This study aimed to investigate any reduction in radiation dose between an older fluoroscopy system (Philips Integris H5000, Philips Healthcare, Einhoven, Netherlands) and one of the latest systems (Siemens Artis Q, Siemens Healthcare, Erlangen, Germany), optimized with dose-reduction strategies. METHODS: Radiation dose measures were collected over a 2-year period in a single electrophysiology laboratory. Procedures were separated into seven groups: devices, biventricular devices, electrophysiology studies, standard radiofrequency ablation, complex atrial ablation, ablation for ventricular arrhythmias, and pulmonary vein isolation. In the first year, an older fluoroscopy system was used, and in the second year, a new system, with dose reduction strategies. Comparisons were also made to the literature with regard to radiation dose levels. RESULTS: Patient characteristics, fluoroscopy times, number of digital acquisitions, procedural times, and procedural success were largely similar between the old and new system across procedure groups. Overall dose area product (DAP) was reduced by 91% (5.0 [2.0-17.0] to 0.45 [0.16-2.61] Gycm2 [P > 0.001]) with the new system and was lower across all groups. DAP readings with the new system are some of the lowest published in the literature in all groups. CONCLUSION: An optimized contemporary digital fluoroscopy system, with low radiation dose configuration and continued good procedural practice, can result in ultra-low radiation levels for all electrophysiology procedures, without compromising procedural time or procedural success.


Asunto(s)
Técnicas Electrofisiológicas Cardíacas/métodos , Fluoroscopía/métodos , Dosis de Radiación , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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