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Modelling the Survival of Western Honey Bee Apis mellifera and the African Stingless Bee Meliponula ferruginea Using Semiparametric Marginal Proportional Hazards Mixture Cure Model

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Journal of Data Analysis and Information Processing 2024年第1期12卷 24-39页

作者： Patience Isiaho Daisy Salifu Samuel Mwalili Henri E. Z. Tonnang Department of Statistics and Actuarial Sciences Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya Data Management Modelling and Geo-Information Unit International Centre of Insect Physiology and Ecology (icipe) Nairobi Kenya

Classical survival analysis assumes all subjects will experience the event of interest, but in some cases, a portion of the population may never encounter the event. These survival methods further assume independent survival times, which is not valid for honey bees, which live in nests. The study introduces a semi-parametric marginal proportional hazards mixture cure (PHMC) model with exchangeable correlation structure, using generalized estimating equations for survival data analysis. The model was tested on clustered right-censored bees survival data with a cured fraction, where two bee species were subjected to different entomopathogens to test the effect of the entomopathogens on the survival of the bee species. The Expectation-Solution algorithm is used to estimate the parameters. The study notes a weak positive association between cure statuses (ρ1=0.0007) and survival times for uncured bees (ρ2=0.0890), emphasizing their importance. The odds of being uncured for A. mellifera is higher than the odds for species M. ferruginea. The bee species, A. mellifera are more susceptible to entomopathogens icipe 7, icipe 20, and icipe 69. The Cox-Snell residuals show that the proposed semiparametric PH model generally fits the data well as compared to model that assume independent correlation structure. Thus, the semi parametric marginal proportional hazards mixture cure is parsimonious model for correlated bees survival data.

关键词： Mixture Cure Models Clustered Survival Data Correlation Structure Cox-Snell Residuals EM Algorithm Expectation-Solution Algorithm

Comparison of Semi-Parametric Shared Frailty Models for Bees’Survival

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Journal of Data Analysis and Information Processing 2024年第2期12卷 267-288页

Survival analysis is a fundamental tool in medical science for time-to-event data. However, its application to colony organisms like bees poses challenges due to their social nature. Traditional survival models may not accurately capture the interdependence among individuals within a colony. Frailty models, accounting for shared risks within groups, offer a promising alternative. This study evaluates the performance of semi-parametric shared frailty models (gamma, inverse normal, and positive stable-in comparison to the traditional Cox model using bees’ survival data). We examined the effect of misspecification of the frailty distribution on regression and heterogeneity parameters using simulation and concluded that the heterogeneity parameter was more sensitive to misspecification of the frailty distribution and choice of initial parameters (cluster size and true heterogeneity parameter) compared to the regression parameter. From the data, parameter estimates for covariates were close for the four models but slightly higher for the Cox model. The shared gamma frailty model provided a better fit to the data in comparison with the other models. Therefore, when focusing on regression parameters, the gamma frailty model is recommended. This research underscores the importance of tailored survival methodologies for accurately analyzing time-to-event data in social organisms.

关键词： Correlated Failure Times Frailty Survival Analysis Unobserved Heterogeneity

Structural,optical and dielectric investigations on RECr_(0.85)Mn_(0.15)O_(3)(RE=Ho,Gd and Pr) nanoparticles

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Journal of Rare Earths 2024年第2期42卷 399-408,I0006页

作者： Komal Kanwar Sonali Pradhan S.Satapathy Yugandhar Bitla Neeraj Panwar Department of Physics Central University of Rajasthan BandarsindrAjmer305817RajasthanIndia Laser Material Section HBNIRaja Ramanna Centre for Advanced TechnologyIndore452013India

We hereby report the room-temperature structural and optical characterization of RECr_(0.85)Mn_(0.15)O_(3)(RECMO,RE=Ho,Gd and Pr) compounds synthesized by the auto-combustion sol-gel *** low temperature dielectric properties are also *** RECMO compounds crystallize in an orthorhombic Pbnm symmetry with an average grain size range of 51-80 *** analysis reveals an increase in the structural distortion compared to that of the undoped bulk *** measurements exhibit a significant reduction in bandgap values for RECMO nanoparticles when compared with their undoped bulk ***,from the absorbance measurements various optical parameters such as skin depth,extinction coefficient,refractive index and optical conductivity were also *** dielectric analysis confirms the lower values of the dielectric permittivity and dielectric loss than those of their corresponding bulk *** conductivity versus frequency and temperature data are fitted according to the Jonscher's power law and Arrhenius law,*** small polaron hopping is responsible for the electric conduction in these *** tunability of the optical and dielectric properties as a result of substitution and particle size reduction makes these materials useful for various potential applications in photocatalysis,optoelectronics and low permittivity dielectrics.

关键词： Rare-earth orthochromites Nanoparticles Optical properties Dispersion parameters Dielectric properties Small polaron hopping

Defect mediated losses and degradation of perovskite solar cells:Origin impacts and reliable characterization techniques

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Journal of Energy Chemistry 2024年第7期94卷 217-253页

作者： Himangshu Baishy Ramkrishna Das Adhikari Mayur Jagdishbhai Patel Deepak Yadav Tapashi Sarmah Mizanur Alam Manab Kalita Parameswar Krishnan lyer centre for Nanotechnology Indian Institute of Technology GuwahatiGuwahati 781039AssamIndia Department of Chemistry Indian Institute ofTechnology GuwahatGuwahati739AssamIndi

The rapid advancement of halide-based hybrid perovskite materials has garnered significant research attention,particularly in the domain of photovoltaic *** to their exceptional optoelec-tronic properties,they demonstrated power conversion efficiency(PcE)of over 25%in single junction solar *** the notable progress in PCE over the past decade,the inherent high defect density pre-senting in perovskite materials gives rise to several loss mechanisms and associated ion migration in per-ovskite solar cells(PsCs)during operational *** factors collectively contribute to a significant stability challenge in PsCs,placing their longevity far behind for *** numerous reports have explored defects,ion migration,and their impacts on device performance,a com-prehensive correlation between the types of defects and the degradation kinetics of perovskite materials and PsCs has been *** this context,this review aims to provide a comprehensive overview of the origins of defects and ion migration,emphasizing their correlation with the degradation kinetics of per-ovskite materials and PsCs,leveraging reliable characterization ***,these charac-terization techniques are intended to comprehend loss mechanisms by different passivation approaches to enhance the durability and PCE of PSCs.

关键词： Perovskite solar cells Defects lon migration Degradation Stability

Bioinspired designs in active metal-based batteries

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Nano Research 2024年第2期17卷 587-601页

作者： Fan Zhang Ting Liao Cheng Yan Ziqi Sun School of Chemistry and Physics Queensland University of TechnologyGeorge StreetBrisbaneQLD 4000Australia School of Mechanical Medical and Process Engineering Queensland University of TechnologyGeorge StreetBrisbaneQLD 4000Australia QUT centre for Materials Science Queensland University of TechnologyGeorge StreetBrisbaneQLD 4000Australia

Active metal-based batteries are drawing increased attention because of their inherent high energy density and specific *** grand challenges,such as dendrite growth,electrode degradation,rapid performance fading,etc.,have limited their practical ***,which involves taking cues from the structures and functions of the natural world,can lead to a wealth of conceptually fresh approaches to regulator the metal ion transportation to achieve a dendrite-free metal plating,thwart the side-reaction reactions,and retard the structural distortions,for a more reliable and secure operation of active metal-based *** this review,we concentrate on the fabrication and application of bioinspired designs in active metal-based batteries with enhanced performance,along with discussion on the challenges and opportunities associated with this promising *** anticipate that this review can offer some insights into the development of functional materials by learning from nature and provide some approaches for the innovations of either the battery structures or the energy materials for metal-based batteries.

关键词： bioinspired materials energy storage devices metal-based batteries

LP modes exchange based on multiplane light conversion

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Chinese Optics Letters 2024年第3期22卷 14-18页

作者：钟亚楠林楚璇方浚丞雷霆袁小聪 Nanophotonics Research centre Shenzhen Key Laboratory of Micro-Scale Optical Information Technology&Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China

Data exchange between different mode channels is essential in the optical communication network with mode-division multiplexing(MDM).However,there are challenges in realizing mode exchange with low insert loss,low mode crosstalk,and high ***,we designed and fabricated a mode exchange device based on multiplane light conversion(MPLC),which supports the transmission of LP01,LP11a,LP11b,and LP21 modes in the C-band and *** simulated exchanged mode purities are greater than 85%.The phase masks were fabricated on a silicon substrate to facilitate the integration with optical systems,with an insert loss of less than 2.2 dB and mode crosstalk below-21 dB due primarily to machining inaccuracies and alignment *** carried out an optical communication experiment with 10 Gbit/s OOK and QPSK data transmission at the wavelength of 1550 nm and obtained excellent performance with the *** paves the way for flexible data exchange as a building block in MDM optical communication networks.

关键词： mode exchange mode-division multiplexing multiplane light conversion

Process and performance of DAAF microspheres prepared by continuous integration from synthesis to spherical coating based on microfluidic system

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Defence technology（防务技术） 2024年第2期32卷 629-643页

作者： Bidong Wu Jiahui Shi Mengsen Wei Rui Zhu Yi Liu Jinqiang Zhou Chongwei An Jingyu Wang School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China Shanxi Engineering technology Research centre for Ultrafine Powder North University of ChinaTaiyuan 030051China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to improve the energy output consistency of 3, 3’-diamino-4, 4’-azoxyfurazan(DAAF) in the new insensitive booster and the safety and efficiency in the preparation process, a continuous preparation system of DAAF from synthesis to spherical coating was designed and established in this paper, which combined ultrasonic micromixing reaction with microdroplet globular template. In the rapid micromixing stage, the microfluidic mixing technology with ultrasonic was used to synergistically strengthen the uniform and rapid mass transfer mixing reaction between raw materials to ensure the uniformity of DAAF particle nucleation-growth, and to prepare high-quality DAAF crystals with uniform structure and morphology and concentrated particle size distribution. In the microdroplet globular template stage, the microfluidic droplet technology was used to form a droplet globular template with uniform size under the shear action of the continuous phase of the dispersed phase solution containing DAAF particles and binder. The size of the droplet template was controlled by adjusting the flow rate ratio between the continuous phase and the dispersed phase. In the droplet globular template, with the diffusion of the solvent in the dispersed phase droplets, the binder precipitates to coat the DAAF into a ball, forming a DAAF microsphere with high sphericity, narrow particle size distribution and good monodispersity. The problem of discontinuity and DAAF particle suspension in the process was solved, and the coating theory under this process was studied. DAAF was coated with different binder formulations of fluororubber(F2604), nitrocellulose(NC) and NC/glycidyl azide polymer(GAP), and the process verification and evaluation of the system were carried out. The balling effects of large, medium and small droplet templates under different binder formulations were studied. The scanning electron microscope(SEM) results show that the three droplet templates under the three binder formul

关键词： DAAF Micromixing technology Microdroplet technology Synthesis Spherical coating Continuousization

High Speed Sintering:Assessing the Influence of Energy Input on Microstructure and Mechanical Properties of Polyether Block Amide(PEBA)Parts

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Chinese Journal of Polymer Science 2024年第5期42卷 675-682,I0004,I0010页

作者： Jiang-Tao Sun Zhi-Yong Fan Yi-Wei Mao Wei Li Wei Zhu Dao-Sheng Cai Qing-Song Wei State Key Laboratory of Materials Processing and Die&Mould technology Huazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430074China National Engineering Research centre for High Efficiency Grinding Hunan UniversityChangsha410082China Wuhan EasyMFG technology CO. LTDWuhan430074China

High speed sintering,a new powder-bed fusion additive manufacturing technology,utilizes infrared lights(IR)to intensely heat and melt polymer *** presence of defects such as porosity,which is associated with particle coalescence,is highly dependdent on the level of energy *** study investigate the influcence of energy input on porosity and its subsequent effects on the mechanical properties and microstructures of PEBA *** parts were manufactured with a variety of lamp powers,resulting in a range of energy input levels spanning from low to ***,they underwent testing using Archimedes’method,followed by tensile *** porosity,mechanical characteristics,and energy input exhibit a strong correlation;inadequate energy input was the primary cause of pore *** the reduced IR light power resulted in the following outcomes:porosity,ultimate tensile strength,and elongation of 1.37%,7.6 MPa,and 194.2%,*** the energy input was further increased,the porosity was reduced to as low as 0.05%and the ultimate tensile strength and elongation were increased to their peak values of 233.8%and 9.1 MPa,respectively.

关键词： High speed sintering Additive manufacturing Energy input Powder bed fusion PEBA

Process,Material,and Regulatory Considerations for 3D Printed Medical Devices and Tissue Constructs

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Engineering 2024年第5期36卷 146-166页

作者： Wei Long Ng Jia Anb Chee Kai Chua Singapore centre for 3D Printing(SC3DP) School of Mechanical and Aerospace EngineeringNanyang Technological UniversitySingapore 639798Singapore centre for Healthcare Education Entrepreneurship and Research@SUTD(CHEERS)Singapore University of Technology and DesignSingapore 487372Singapore

Three-dimensional(3D)printing is a highly automated platform that facilitates material deposition in a layer-by-layer approach to fabricate pre-defined 3D complex structures on *** is a highly promising technique for the fabrication of personalized medical devices or even patient-specific tissue *** type of 3D printing technique has its unique advantages and limitations,and the selection of a suitable 3D printing technique is highly dependent on its intended *** this review paper,we present and highlight some of the critical processes(printing parameters,build orientation,build location,and support structures),material(batch-to-batch consistency,recycling,protein adsorption,biocompatibility,and degradation properties),and regulatory considerations(sterility and mechanical properties)for 3D printing of personalized medical *** goal of this review paper is to provide the readers with a good understanding of the various key considerations(process,material,and regulatory)in 3D printing,which are critical for the fabrication of improved patient-specific 3D printed medical devices and tissue constructs.

关键词： 3D printing Bioprinting Biofabrication Medical devices Tissue constructs