bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of various parameters on the current distribution and protection degree of impressed current cathodic protection for reinforced concrete with TiMMO mesh anodes
Authors: Debaene Robin , Van Belleghem Bjorn , Soetens Tim , Craeye Bart
Published: April 2023

Impressed current cathodic protection (ICCP) is an effective technique to control reinforcement corrosion in concrete structures. The efficiency and design of an ICCP system with titanium mixed metal oxide (TiMMO) anodes in a mortar overlay is strongly influenced by the current distribution to the different reinforcement layers of a reinforced concrete element. An in-depth experimental study is performed to investigate the effect of various parameters on the current distribution and degree of corrosion protection: (i) chloride content, (ii) cement type, and (iii) reinforcement configuration. 24-hour depolarization measurements (EN ISO 12696:2022) indicate that an increase in chloride concentration in the concrete, related to an increase in the rate of reinforcement corrosion, leads to a general decrease in the degree of protection. The use of a CEM III/A cement leads to a large increase in concrete electrical resistivity compared to concrete with an ordinary Portland cement (CEM I). This causes a lower total current output to the reinforcement and a less uniform distribution of current. Finally, a lower steel reinforcement density resulted in a larger current density, as the total current is distributed over a smaller steel surface area, causing higher depolarization values.
Evaluation of the self-healing effect in cement-based materials with embedded cementitious capsules by means of Acoustic Emission techniques
Authors: Anglani Giovanni , Montanari Pedro Marin , Marc Tulliani Jean , Lacidogna Giuseppe , Antonaci Paola
Published: April 2023

Due to its low tensile strength and the presence of defects brought on by improper construction methods or other factors, cracks in concrete are practically inevitable. For reinforced-concrete structures, even if cracks do not necessarily increase the risk of collapse, they unquestionably hinder aspects such as service life. Self-healing cementitious materials have been developed because of growing concern for the security and sustainability of structures. For these new materials to be used in actual structures, it is essential to conduct research into the self-repair effect that they may offer, and possibly quantify it directly on-site, by means of non-destructive methods. In this sense, the objective of this work is to use Acoustic Emission (AE) analyses to non-destructively characterise the response of an autonomic capsule-based system, as a function of the specific polymeric healing agents contained in the capsules. Comparisons will be made between the reference and selfhealing specimens, and between the different self-healing specimens themselves, through the analysis of such parameters as the ultimate load, absorbed fracture energy, and emitted Acoustic Emission (AE) energy. Such type of analysis can give valuable insights not only on quantitative but also on qualitative aspects (such as the level of brittleness or ductility introduced by the specific self-healing system adopted) in view of possible applications in real structures.
PVDF-based coatings with CNT additions for strain monitoring of mortar substrates subjected to bending
Authors: Milone Gabriele , Tulliani Jean-Marc , Al-Tabbaa Abir
Published: April 2023

Sensing coatings are rapidly entering the field of non-destructive tests. While cement-based composites are proving an excellent interaction with new/recent structures, polymer-based coatings, already employed for structural retrofitting purposes, can provide a valuable alternative.

This study investigated the production, application, and use of poly(vinylidene fluoride) (PVDF) coatings. A 10w/v% PVDF-to-solvent ratio became the best trade-off between electrical conductivity and bond strength with the substrate. Different concentrations of Carbon Nanotubes (CNT) were investigated: 0.05, 0.10, 0.25, 0.50, and 0.75% by weight of PVDF. The conductive PVDF-CNT composites were brushed on the casted mortar beams with screws embedded as electrodes. The mortar beams and attached polymer coatings were then subjected to bending stress.

The Gauge Factor was obtained by comparing the substrate’s strain with the coating’s electric response. The sensing intervals in the Fractional Change of Resistance-strain curves varied in relation to the CNT concentration. For instance, adding 0.50w/v% of CNT gave the highest sensitivity up to 0.2‰ strain, followed by a lower – still sufficient – gauge factor. PVDF-based coatings with CNT additions of 0.25 and 0.75w/v% witnessed a comparable sensing performance in the same strain limits, abruptly increasing and finally stabilizing to a low gauge factor. In contrast, both 0.05 and 0.10w/v% resulted in a low monitoring potential overall.

The varying sensing zones experienced by the coating were attributed to the microscopical behavior of CNT within the PVDF matrix. In conclusion, the results highlighted the potentiality of polymeric coatings for sensing, monitoring, and inspection of concrete structures.
Initial proposal of a smart cement-based material to enhance the service-life of reinforcement concrete structures
Authors: Martínez-Ibernón Ana , Antonaci Paola , Anglani Giovanni
Published: April 2023

The sustainable development of societies can be pursued by simultaneously avoiding the depletion of materials and resources and reducing the greenhouse gases emissions, with related climatic change effects. In order to get this, the extension of structures service-life plays a significant role in saving natural resources, decreasing the overall anthropogenic carbon-footprint, and reducing building and demolition wastes. In order to achieve such prolongation of structures service-life, one of the most promising approaches is the development of Smart Structures. These are defined as structures that are able to self-sense some external stimuli such as stress or temperature variations, and internal conditions such as chloride penetration, concrete carbonatation, etc. Consequently, ongoing damage phenomena can be detected promptly, thus allowing to implement suitable countermeasures in the most efficient way. Smart Structures can also process the information and respond autonomously in real time by using smart materials technologies such as self-healing technology. In this study we propose a preliminary version of a smart material system with self-healing and sensing properties, to demonstrate its effectiveness at a proof of concept level. The effectiveness of an active, capsule-based self-healing system in blocking chloride penetration through the crack and the effectiveness of voltametric Ag sensors in detecting the presence of chlorides were investigated experimentally. High-performance cement mortar was chosen as the material to be studied, in order to ensure that optimal behaviour could be observed in non-cracked conditions.
Galvanic corrosion and cathodic protection of re-grouted, post-tensioned (PTd) concrete systems
Authors: Manickam Karthikeyan , Pillai Radhakrishna G.
Published: April 2023

Grouted post-tensioned (PTd) concrete systems are widely used in long-span segmental bridges with a target service life of 100+ years. However, the usage of inadequate grout materials and grouting practices have resulted in the formation of unwanted air voids in the duct, which in turn led to premature corrosion (say, within about 20 years) of strands and failure of tendons. Also, the re-grouting/repairing of void regions have led to localized corrosion of strands at the interface between the dissimilar base-grout (usually carbonated) and repair-grout. This study aims (i) to quantify the galvanic corrosion at the void region in a PTd system re-grouted with a dissimilar grout and (ii) to develop cathodic protection system to protect PTd anchorage regions. Specimens simulating the re-grouted strand-grout-air (SGA) interface were prepared with prestressing steel wires and cementitious grout. The macro-cell current (galvanic current) between the prestressing steels embedded in carbonated base-grout and repair-grout indicated that galvanic corrosion can be possible at the SGA interface – reducing the long-term structural reliability of re-grouted PTd bridges. In addition, the feasibility of galvanic anode cathodic protection system to protect PTd anchorage regions was assessed. For this, a proof-of-concept study was conducted to validate that a thin layer of grout around the strand will be sufficient for a galvanic anode (connected to the end of the strand at outside the tendon anchorage) to protect the strand portions inside the duct/anchorage.
Inhibition Mechanism of Oxalhydrazide on Reinforcing Steel in Pore Solution Contaminated by 3.5%NaCl - Experimental and Theoretical Study
Authors: Subash Smrithy , Moharana Sumedha , Sistla Yamini Sudha
Published: April 2023

Concrete is one among the most consumed materials on the planet secondary to water. However, the degradation of concrete happens due to the corrosion of reinforcement. Although the pore solution of concrete is alkaline, the corrosion of rebars in concrete is triggered due to aggressive ions like chlorides entering the concrete. The most common method of corrosion inhibition is by utilising corrosion inhibitors which when added to the concrete stays in the pore solution and prevents the corrosion of surface of rebars from aggressive ions. Although there are number of inhibitors, the rise in corrosion deterioration demands the need for new potential inhibitors which are highly effective in different aggressive environments. This study is based on the corrosion of rebars in simulated concrete pore solution in the presence of 3.5% NaCl with oxalhydrazide as the potential inhibiting material. The corrosion behaviour of rebar is obtained by electrochemical studies using EIS and potentiodynamic polarization and theoretically analysed employing molecular mechanics and molecular dynamics simulations. The experimental results revealed that the inhibitor is effective in reducing the corrosion and the values of binding energy of the inhibitors on rebar surface also go well with the experimental results. Oxalhydrazide is found effective in minimizing the attack of chloride ion on rebar in pore solution.
Performance evolution and tensile behaviour of long-term exposed UHPC under sustained load, aggressive environments and autogenous healing
Authors: Davolio Marco , Recchia Giovanni , Altomare Maria Ylenia , Soave Francesco , Al-Obaidi Salam , Ferrara Liberato
Published: April 2023

An extended experimental campaign was conducted to analyse the evolution of UHPC tensile performance over time as affected by sustained flexural load and aggressive environments both interacting with its autogenous self-healing capacity. A new methodology including both destructive and non-destructive tests was proposed. Three different mix designs were tested, with steel fibres, crystalline admixture, and various nanomaterials. Specifically, the first batch included alumina nano-fibres, while the second one cellulose nanocrystals. The last one was used as a reference and did not include nanomaterials. Thin beam specimens (500x100x30 mm) were pre-cracked and exposed to three different environments, under four-point bending sustained load. The specimens were cured for 1, 2, 3, 6, 9, and 12 months respectively, being exposed to a chloride solution, geothermal water, and tap water as a reference. After the aforesaid scheduled exposure times, two nominally identical specimens were tested for each condition, the first in four-point bending and the second in direct tension. To compare the results, a simplified five-point inverse analysis was adapted for beams with different slenderness, providing a quadrilinear constitutive law derived from the structural flexural behaviour of four-point bending tests. Test results allowed to highlight the effects of each parameter – type of material and exposure – on the self-healing effectiveness and the tensile response, also defining their evolution over time. The self-healing process resulted in an almost complete recovery after the first two or three months, and the materials were able to maintain a constant performance over longer periods, regardless of the conditions they were exposed to.
Nano-additives and their effects on the microwave absorptions and mechanical properties of the composite materials
Authors: Zena Yared G. , Woldemariam Mulugeta H. , Koricho Ermias G.
Published: April 2023

The review addresses the effect of various carbon and iron-based percentage nano- additives on both electromagnetic (EM) wave and mechanical properties of composite materials. It also assessed the influence of particle and fiber size along with the manufacturing process, on mechanical properties (tensile strength and flexural strength), fracture behaviors (fracture toughness) and electromagnetic properties (reflection loss). Reviewing the selection of nanomaterials for a particular frequency band and application, as well as their impacts on bulk materials in relation to loading, were overviewed. As per this review, adding those iron and carbon-based additives influence positively for both electromagnetic and mechanical properties. Furthermore, review organized natural based fiber and filler-based composites along with fillers for the production of green strong radar materials. The review also showed, how highest and smaller percentage of iron-based fillers affected for microwave absorption and mechanical properties. Mainly, the optimized use of nano particles percentage for both mechanical and electromagnetic wave to produce strong radar materials were overlooked. Finally, these papers give a quick hint on how these nano particles manufacturing methods and particle size affect the mechanical properties and micro wave absorption of composite materials.
Output trajectory controllability of a discrete-time sir epidemic model
Authors: Benahmadi Lahbib , Lhous Mustapha , TRIDANE Abdessamad , Rachik Mostafa
Published: April 2023

Developing new approaches that help control the spread of infectious diseases is a critical issue for public health. Such approaches must consider the available resources and capacity of the healthcare system. In this paper, we present a new mathematical approach to controlling an epidemic model by investigating the optimal control that aims to bring the output of the epidemic to target a desired disease outputyd= (ydi)i∈{0,...,N}. First, we use the state-space technique to transfer the trajectory controllability to optimal control with constraints on the final state. Then, we use the fixed point theorems to determine the set of admissible controls and solve the output trajectory controllability problem. Finally, we apply our method to the model of a measles epidemic, and we give a numerical simulation to illustrate the findings of our approach.
Assessment of the impact of a decrease in crude protein content in monogastric feed on oilseeds meals and legumes, prospective approach
Authors: Guilbaud Thomas , Martin Nicolas , Lambert William , Le Cour Grandmaison Josselin , Bourgeat Emmanuelle
Published: April 2023

The present study evaluates the consequences of a change in pig and poultry protein nutrition through compound feed over time in France, on raw materials consumption, economic performances, and environmental impacts. It has been conducted using the “Prospective Aliments” model by Céréopa, which applies the principles of linear programming at a national scale (France). The study is based on a prospective approach. A decrease of 1 and 2 percentage points in pig and poultry feed crude protein (CP) content is applied (CP-1 or CP-2, respectively). As a consequence, consumptions of raw materials for total French compound feed production change drastically, by using rapeseed meals, over soybean meals (−425 000 t for CP-2) and sunflower meals, and including more grains, with maize replacing wheat. This shows that the feed CP content of commercial feed can be decreased at a national scale, yielding significant environmental benefits. This raises the question of developing an incentive-based policy to absorb potential over costs.
Optimization of energy cycle under a sustainable supply chain management
Authors: Sarkar Mitali , Majumder Abhijit , Bhattacharya Santanu , Sarkar Biswajit
Published: April 2023

The energy supply chain research is very much essential as the amount of non-renewable or traditional energy is fixed and finite. In contrast, the energy demand is high and continuously increasing. An energy supply chain model is studied with a waste-supplier and an energy-supplier. The waste-supplier collects wastes and transfers them to the energy-supplier for energy conversion. This energy chain is managed among players and studied how the energy can be distributed to consumers such that no shortage of energy occurs. The model is formulated on the different waste and energy cycles. The supply chain’s minimum total cost is acquired using the optimum cycle length of the energy cycle. The model is solved with a classical optimization method. The closed-form solution is obtained with the global minimum cost. The numerical assessment is investigated to prove the validity of the proposed study. Through the numerical findings and sensitivity exploration, several managerial insights are provided. The numerical investigation obtains that the recommended strategy can provide a non-shortage benefit of energy allotment. The total cost can be saved up to 93.82% for the renewable energy conversion with the same energy and waste cycle with no discarded wastes. For different energy and waste cycle with no discarded wastes, the total cost can be reduced by 21.83%.
Study on the coupling and coordination relationship between ecological environment and economic development in Heyuan City
Authors: Zeng Yuan
Published: April 2023

Quantitative research on the coordination between ecological environment and economic development is of great significance to the realization of the goal of sustainable development. Taking Heyuan City as the research object, this paper constructs the indicator system of ecological environment and economic development, selects the relevant indicator data of ecological environment and economic development of Heyuan City from 2005 to 2021, establishes the coupling coordination degree model, and conducts an empirical analysis of the relationship between the ecological environment and economic development of Heyuan City. The research shows that the coupling degree between the ecological environment and economic development of Heyuan City has been at a high level during the period from 2005 to 2021, and the overall coupling coordination degree has been steadily rising, and has gone through various stages from barely coordinated to high-quality coordinated development; The economic development of Heyuan City has also developed from lagging behind the ecological environment to the synchronous development of both.
Status and prospects of HKG offshore market based on RMB internationalization: A non-linear regression model using Granger-causality test
Authors: Gao Lihong , Zhang Jing
Published: April 2023

Over the past eighteen years, Hong Kong has developed the simple deposit business of the local RMB market into the world’s largest offshore RMB hub by virtue of its advantages as an international financial center.

Firstly, this paper introduces the specific situation of cross-border use of RMB, collects historical data on the offshore RMB market in Hong Kong through a desktop research approach, and reviews the development of the offshore RMB market in Hong Kong using the process of RMB internationalization as a clue. Secondly, the current opportunities and challenges facing the Hong Kong offshore RMB market are elucidated from three dimensions: demand, supply and exchange rate movements of RMB in the Hong Kong offshore market, respectively. To further illustrate the potential development of Hong Kong’s offshore market, this paper takes the development of offshore financial markets and RMB internationalization as a specific entry point, constructs a quantitative model, and obtains the conclusion that offshore financial markets have a positive impact on the internationalization process of RMB. On this basis, the paper illustrates the development potential of Hong Kong’s offshore market in the context of its specific situation. Finally, synthesizing the reflections in the whole paper, this paper makes certain analysis on the development direction of Hong Kong’s offshore market in the light of the blueprint of the national 14th Five-Year Plan.
Investigation and Analysis of the Current Situation of MOOC Learning among University Students in the Post-epidemic Period --Xi’an Jiaotong University as an Example
Authors: Jingyi Zhang , Hongyi Duan , Peng Tian , Xueqian Gan
Published: April 2023

MOOC, whose full name is Massive Open Online Course, usually refers to the free and open online learning platform for the whole society. MOOC has received a lot of recognition from the academic community for its advantages of course diversity, platform openness and learning autonomy. Nowadays, MOOC has entered the universities and become a platform for students to learn professional knowledge. The importance of MOOC in academics cannot be ignored, and it is imperative to understand the views of college students as the main audience group and make corresponding suggestions to optimize knowledge absorption.
Performance Evaluation and Improvement Countermeasures of the Real Estate Regulation Policy in Dongguan
Authors: Zhang Shuyu
Published: April 2023

With the development of modern society, the real estate industry is closely related to people’s production and life, and it is an important industry related to the national economy and people’s livelihood. Local development not only needs the real estate to promote economic prosperity, but may also harm the development of the real economy, bringing potential financial risks. In order to alleviate the real estate problems and contradictions in the process of development, the Dongguan government has frequently introduced various relevant control policies, but the housing price rises too fast, the supply and demand imbalance in the real estate market, the supply structure imbalance and other problems are still serious. Practice shows that the real estate industry can develop more smoothly by combining the market’s selfregulation with the government’s macro-control. This paper introduces the real estate market and policy of Dongguan City. On this basis, combined with the relevant data of the real estate industry in Dongguan, the effect of the real estate policy was evaluated, and the advantages and shortcomings of the implementation of the real estate control policy in Dongguan were analyzed. Through quantitative and qualitative analysis methods, this paper further screens the primary indicators for the different impacts brought by the performance of the real estate regulation policies, and adopts the principal component analysis method to quantitatively evaluate the performance of the real estate regulation policies in Dongguan City during 2019-2021. Finally, this paper puts forward suggestions to improve the real estate regulation policies in Dongguan City.
Block Chain Policy’s Impact on Firms’ Performance Based on PSM-DID
Authors: Tan Siyue
Published: April 2023

Early in 2020, China’s National Development and Reform Commission initially outlined the parameters of new infrastructure, with blockchain technology serving as a crucial tenet. A technologically advanced infrastructure system based on information networks, targeted at the requirements of high-quality development, and offering services like digital transformation, intelligent upgrades, and integrated innovation is what is hoped to be built. This study builds a DID model for analysis and aims to investigate how the adoption of the blockchain policy has affected the performance of various carbon emission enterprises. The paper discovered that blockchain regulation has a negative impact on the performance of high-carbon emission businesses using the DID model. A robustness assessment using PSM-DID reveals the same results. Furthermore, we found that the current ratio and ttm had a positive impact on corporate performance. This paper still has some limitations. To explore the impact of blockchain policy on the performance of various types of organizations, the article does not take into account the state-owned and non-state-owned qualities of enterprises. Future research on this topic will focus on the characteristics of businesses.
Research of the fiscal and tax policies of High - tech industry in Northeast China
Authors: Jing Hongjun , Li Bolun
Published: April 2023

In recent years, the high-tech industry has become an important driving force for economic development, and it has become an important subject to study the fiscal and tax policies suitable for the development of local high-tech industry. This paper constructs a fixed-effects linear regression model with unbalanced panel data by selecting data related to high-tech industries listed in China in three northeastern provinces to empirically test the effects of fiscal subsidies and tax incentives on innovation inputs, outputs and economic benefits of enterprises. The result show that fiscal policies mainly motivate the development of high-tech industry R&D and innovation output, and the tax policies motivate the development of hightech industry R&D and economic benefit. The fiscal and tax policies have different effect to different enterprises, private enterprises will develop better than state-owned enterprises. To motivate the development of high-tech industry, government should formulate fiscal and tax programs according to the effects of fiscal and tax policies in different stages of the industrial chain, determine the leading methods, adjust the content of the existing fiscal and tax policies according to the characteristics of enterprises. The innovation point of this paper is to analyze the relationship between innovation R&D input, innovation output and revenue and fiscal policy related to high-tech industry from the perspective of complete industrial chain, and systematically compare the effect of existing fiscal policy and tax policy in three northeastern provinces, which provide a reference for future research related to the development of regional high-tech industry.
An analysis of logistics financing prospects in Singapore
Authors: Shao Shiyu , Yang Zixuan , Si Wenjia
Published: April 2023

Singapore is well-positioned as a global hub for logistics and supply chain management. Singapore’s modern logistics industry has five main characteristics: high efficiency, robust technology, strong professionalism, high service concentration and strength. Singapore is a foreign trade-driven economic model. With the prosperity of cross-border trade, companies in the logistics industry in Singapore seek diversification and expansion of supply chain technology and logistics finance. This paper mainly analyses the advantages of Singapore’s development of the logistics industry and the promotion effect of Singapore’s growth in the financial field on logistics industry financing. Factors such as the Internet of Things, blockchain, intelligent management, talent cultivation and policy support are enormous drivers for developing logistics financing in Singapore. Among them, the most representative and promising is the blockchain platform, which provides technical support for the Internet of everything, improves the security of multi-agent cooperation, and expands the scope of credit transmission. Although there are still some risks in developing logistics financing in Singapore, as a potent combination of the financial and logistics industries, logistics financing has a bright prospect.
A BERT-CNN Based Approach on Movie Review Sentiment Analysis
Authors: Zhang Bowen
Published: April 2023

Sentiment analysis plays a vital role in the decision-making of multiple fields. Specifically, in movies and television, audiences’ reviews can help with casting, the direction of the plot, etc. To further improve the performance of the original BERT model, a BERT-CNN-based approach is proposed in this paper to do sentiment analysis on IMDb dataset. Although their performances are nearly the same throughout the research, the BERT-CNN approach is better at negative sentiment detection. It got an average elevation of 3.6% in accuracy after the ensemble. Apart from that, topic modeling is also performed to show that most negative reviews are commented on from multiple aspects instead of criticizing only, making sentiment analysis of movie reviews a complex problem.
The Effect of Cultural Capital on Students’ Academic Motivation in the Context of Involution: Ecological Perspective
Authors: Gan Ning
Published: April 2023

This study aims to explore the effect of cultural capital on academic motivation in the context of involution in China. The study will employ an ecological perspective to understand the interaction between college students and the involuted Chinese social context and job market, and the interaction mechanism between cultural capital and academic motivation. The concept of involution refers to the decreased “effort-to-reward ratio” in the education system, which has been impacted by the COVID-19 outbreak and the popularity of internet companies for college graduates. Cultural capital, as defined by Bourdieu, refers to a form of capital that can be converted into economic capital and is institutionalized in the form of educational credentials. The study will consider the three forms of cultural capital (objectified, embodied, and institutionalized) and their impact on academic motivation at the school, family, and individual levels. The results of this study will provide insight into the complex relationship between cultural capital and academic motivation in the involuted context in China and will have implications for understanding the phenomenon of study and employment involution.
Is Government Provision Necessary for Rural Credit Gap? Evidence from China
Authors: Liao Bingwu , Shen Murong
Published: April 2023

The shortage of rural credit supply is a global practical problem, and also a concern of the world academia. The purpose of this study is to find evidence of the role of government provision in solving rural credit gap, and provide inspiration for countries to solve the shortage of rural credit supply. In the process, this study uses Goldsmith’s financial development theory as the theoretical guidance, and conducts an empirical analysis of the relationship between the financial interrelations ratio (FIR) and government provision in rural China from 2004 to 2019. The findings show that the rural credit gap with market development is not necessarily a credit market failure, and the government provision is not necessarily effective. Because the government provision is costly, wasteful, and less efficient than government intervention on stimulating demand.
Internal governance structure and characteristics of private colleges and universities - Based on the analysis of constitution of 7 private universities in Zhejiang Province
Authors: Yu Xiaomin , Wang He
Published: April 2023

By combing the constitution of 7 private colleges and universities in Zhejiang Province, this paper summarizes the law of internal governance of private colleges and universities, analyzes the structure and characteristics of internal governance of private colleges and universities, and puts forward some thoughts.
Pluronic F-68 Montmorillonite As A Drug Delivery Vehicle For Extended
Release Of Venlafaxine Hydrochloride
Authors: Jain Shilpa , Datta Monika
Published: April 2023

Short half-life and low bioavailability of Venlafaxine hydrochloride (VF), an
antidepressant drug, necessitates the frequent administration of VF tablets in a
day in order to maintain adequate drug concentration in blood plasma. This
generates the need for the development of formulations which could prolong the
release of VF and reduce the multiple dosages. The present work explores the
combination of Montmorillonite (Mt) with Pluronic F-68 (PF-68) (OrganoMT) for
oral delivery of VF. The effect of various parameters including pH of aqueous
drug solution, contact time and initial drug concentration on drug loading
capacity of OrganoMT has been studied. The synthesized OrganoMT-VF complexes
were characterized by various suitable techniques. XRD studies indicated that
the VF molecules were intercalated within the OrganoMT layers. In vitro release
behavior of VF from OrganoMT-VF complexes shows an extended-release pattern for
a period of 30 h and reaches upto 70% and 60% compared
to pure VF having complete release time of 5.5 h and 3.5 h in
simulated gastric and intestinal fluid respectively. Various kinetic models were
employed to elucidate the drug release mechanism where the best fitting was
obtained with Korsmeyer Peppas model. The results suggest the possibility of
designing an oral extended controlled release formulation for VF to minimize its
administration frequency thereby increasing the effectiveness of drug. This
improves patient compliance by reducing the dose from 4 times in 24 h to
once in 24 h.
Myxedema Heart Disease in a Teenage Child
Authors: Bennett Jean M. , Bridwell Rachel E. , Percival Candace S. , Malhotra Monesha Gupta , Appachi Elumalai , Salameh Mohammed
Published: April 2023

Myxedema heart disease is an exceptionally rare condition with few reported cases. We present a rare case of a child who presented with severe congestive heart failure secondary to myxedema heart disease complicated by preexisting valvular heart disease. The patient was admitted to the pediatric intensive care unit and medical management. An echocardiogram showed severe biventricular dysfunction and severe valvular disease. She was started on levothyroxine and liothyronine. During the patient's hospitalization, the thyroxine level normalized but the thyroid-stimulating hormone continued to remain elevated. Likewise, her cardiac ventricular function improved, though it did not return to baseline. Our case highlights the importance of maintaining a broad differential diagnosis in a child who presents with congestive heart failure, to include thyroid disease, which necessitates a rare but specific management strategy.
Chemical constituents of lawang root oil
Authors: Alnafta Neanne , Graham Marlowe , Proschogo Nicholas W. , McErlean Christopher S. P.
Published: April 2023

Spectroscopic analysis of lawang root oil identified methyl salicylate as the major component. This result contrasts with the known composition of bark-derived lawang oil, in which eugenol is the major component. The validity of the compositional analysis was confirmed by extraction of an authentic sample of plant root tissue, and comparison with the commercially available essential oil.
Artemisinin and Ambrosia trifida extract aggravate the effects of short freeze–thaw stress in winter rye (Secale cereale) seedlings
Authors: Guo Jiancai , Bao Guozhang , Zhang Xin , Pan Xinyu , Zhao Hongwei , Fan Cunxin , Li Guomei
Published: April 2023

The freeze–thaw and allelopathy from alien giant ragweed (Ambrosia trifida L.) and artemisinin have led to a serious stress to plants, influencing the agricultural quality and crop yield in north-east China. Yet, little is known how allelopathy affect plants under the freeze–thaw process. In this study, the characteristics in winter rye (Secale cereale L.) seedlings were investigated by laboratory simulation. The results showed that during the freezing process, application of artemisinin and A. trifida extract significantly increased the soluble protein content and accelerated lipid peroxidation, while they significantly inhibited antioxidant enzymes, photosynthesis and respiration (P < 0.05). During the thawing process, the freezing pressure decreased, and activities of antioxidant enzymes were significantly improved to mitigate artemisinin and A. trifida extract induced stress (P < 0.05). In addition, the sensitivity of the investigated metabolic processes in winter rye seedlings were highest to artemisinin and A. trifida extract in the freezing process. This study suggested that the stress response induced by artemisinin and A. trifida extract on winter rye seedlings in the freezing process was greater than that in the thawing process.
Modelling plants across scales of biological organisation for guiding crop improvement
Authors: Wu Alex
Published: April 2023

Grain yield improvement in globally important staple crops is critical in the coming decades if production is to keep pace with growing demand; so there is increasing interest in understanding and manipulating plant growth and developmental traits for better crop productivity. However, this is confounded by complex cross-scale feedback regulations and a limited ability to evaluate the consequences of manipulation on crop production. Plant/crop modelling could hold the key to deepening our understanding of dynamic trait–crop–environment interactions and predictive capabilities for supporting genetic manipulation. Using photosynthesis and crop growth as an example, this review summarises past and present experimental and modelling work, bringing about a model-guided crop improvement thrust, encompassing research into: (1) advancing cross-scale plant/crop modelling that connects across biological scales of organisation using a trait dissection–integration modelling principle; (2) improving the reliability of predicted molecular–trait–crop–environment system dynamics with experimental validation; and (3) innovative model application in synergy with cross-scale experimentation to evaluate G × M × E and predict yield outcomes of genetic intervention (or lack of it) for strategising further molecular and breeding efforts. The possible future roles of cross-scale plant/crop modelling in maximising crop improvement are discussed.
Apple puree as a natural fructose source provides an effective alternative carbohydrate source for fuelling half‐marathon running performance
Authors: Reynolds Kirsty M. , Juett Loris A. , Funnell Mark P. , Schofield Joshua B. , Grundig Claire , Melidis George , Brown Alexander , Hubbard Will , Luo Yuxuan , Almahaireh Ibrahim , James Lewis J. , Mears Stephen A.
Published: April 2023

Carbohydrate supplementation during endurance exercise is known to improve performance, but the effects of food‐based approaches in running exercise are understudied. Therefore, this study investigated the performance and gastrointestinal (GI) effects of a carbohydrate supplement containing a natural fructose source compared with a highly processed fructose source in a combined glucose‐fructose supplement, during a half‐marathon. Eleven trained runners (9 males, 2 females; age 32 ± 8 y, 89:53 ± 13:28 min half‐marathon personal record) completed a familiarisation (8 miles) and two experimental trials (13.1 miles) on an outdoor running course, with blood and urine samples collected before and after the run. Subjective GI measures were made throughout the run. Carbohydrate was provided as a natural fructose source in the form of apple puree (AP) or highly processed crystalline fructose (GF) in a 2:1 glucose‐to‐fructose ratio (additional required glucose was provided through maltodextrin). Half‐marathon performance was not different between carbohydrate sources (AP 89:52 ± 09:33 min, GF 88:44 ± 10:09 min; P = 0.684). There were no interaction effects for GI comfort (P = 0.305) or other GI symptoms (P ≥ 0.211). There were no differences between carbohydrate sources in ad libitum fluid intake (AP 409 ± 206 mL; GF 294 ± 149 mL; P = 0.094) or any other urinary (P ≥ 0.724), blood‐based (P ≥ 0.215) or subjective (P ≥ 0.421) measures. Apple puree as a natural fructose source was equivalent to crystalline fructose in supporting half‐marathon running performance without increasing GI symptoms.
Periodic environmental effect: stochastic resonance in evolutionary games of rock-paper-scissors
Authors: Ma Hong-Yi , Liu Cong , Wu Zhi-Xi , Guan Jian-Yue
Published: April 2023

A balance in nature is maintained by the coexistence of multiple species through interspecific competition. The evolutionary dynamics of cyclic interactions contain interactions that represent different biological behaviors. Biological behavior is influenced by the external environment, which may affect the stability of ecosystems. We investigated the evolutionary dynamics of interspecific competition after a periodic change in the external environment affects species. We consider that when the periodic external environments affect mortality, interspecific cyclical competition may be more pronounced, and thus increase the probability of extinction of species. By performing Monte Carlo simulations, we observed that the evolutionary dynamics of interspecific cyclic competition have different responsivity when subjected to external periodic changes at different frequencies, and stochastic resonance phenomena occurred. We show that the influence of the periodic external environment and its frequency is one of the factors that determine whether ecosystems coexist stably.
Compton scattering of plasmons
Authors: Mendonça J Tito , Haas Fernando
Published: April 2023

We extend de concept of Compton scattering to the case of plasmons. This concept was originally applied to electrons in vacuum. Here, we consider electrons in a plasma, and study the scattering properties of photon-plasmon interactions. We show that a number n of plasmons with frequency ω ≃ ω

p
is scattered by an electron, for an incident photon with frequency

ω
′
≥

ω

p

, where ω

p
is the plasma frequency. We describe the general case of arbitrary n and assume that Compton scattering of plasmons is intrinsically a nonlinear process. Our theoretical model is based on Volkov solutions of the Klein–Gordon equation describing the state of relativistic electrons, when the spin is ignored. We derive the corresponding scattering probability, as well as the recoil formula associated with arbitrary final electron states. This process can be relevant to intense laser-plasma interactions.
On the interaction between ultralight bosons and quantum-corrected black holes
Authors: Guo Rong-Zhen , Yuan Chen , Huang Qing-Guo
Published: April 2023

Both ultralight dark matter and exploring the quantum nature of black holes are all topics of great interest in gravitational wave astronomy at present. The superradiant instability allows an exotic compact object (ECO) to be surrounded by an ultralight boson cloud, which leads to the emission of gravitational waves and further triggers rich dynamical effects. In this paper, we study the gravitational effects of superradiant instabilities by calculating the energy fluxes of gravitational waves emitted from ultralight scalar dark matter fields by solving the Teukolsky equation in the background of a massive ECO phenomenologically described by a Kerr geometry with a reflective boundary condition at its physical boundary. We find that both the amplitude and phase of the reflectivity will either suppress or enhance the energy flux of GWs by several orders of magnitude if Mμ ≳ 0.5 where M and μ are the mass of ECO and boson, respectively. However, the modifications to energy flux are negligible if Mμ ≲ 0.5. Our results suggest that reflectivity will play a significant role in the near-horizon physics of ECO.
Manifestly unitary cosmological perturbation theory
Authors: Christeas Panagiotis , Thomas Logan
Published: April 2023

The next decade will feature an abundance of novel cosmological data, while many fundamental questions about inflation remain. Given this, there is ample need for maximally efficient calculations, especially in non-standard scenarios for the early Universe. In inflationary cosmology, observables are computed within the framework of in-in perturbation theory. Weinberg introduced a now-widely used re-organization of perturbation theory for in-in calculations. There is a subtle difference in the iϵ prescriptions of Weinberg's perturbation series with traditional in-in, which could interfere with the projection onto the interacting vacuum. In this work, we show that a small adjustment to Weinberg's perturbation series yields agreement with standard in-in at every order of perturbation theory for commonly studied spins and masses in de Sitter spacetime. We then generalize the result to a large class of cosmological spacetimes, including slow roll spacetimes.
Investigation of thermal effect on the output characteristics of end-pumped Ho:YLF laser in concave–concave and concave–convex resonators
Authors: Tooski Majid Babaiy , Maleki Abbas , Ebadian Hassan , Zamani Majid , nejhad Hamid Salmani
Published: April 2023

The thermal effect on the output characteristics was analyzed in an end-pumped Ho:YLF laser by applying the Kirchhoff integral analytic solution and finite element analysis using LASCAD software. At a Tm:fiber laser power of 70 W, the maximum temperature of a Ho:YLF crystal with 8 mm diameter was found to be 297.6 K. The temperature distribution results of the two calculation methods were matched with an acceptable error. The calculated thermal lens focal length for the maximum power was −985 and −976 mm in the 3 and 8 mm diameter rods, respectively. The simulation results showed that for the larger diameter crystal, the thermal lens effect is less. Moreover, in this study, the calculation results were validated as experimental results. A focal length of the thermal lens of −1012.6 ± 101.26 mm at double-pass pumping was measured. The experimental study showed that laser characteristics such as the far-field divergence angle were improved in the concave–convex resonator with 0.5% Ho:YLF crystal. The experimentally measured divergence angle was 0.7 mrad, which confirms the simulation results. The output power was 13.5 W, corresponding to 19.3% optical-to-optical efficiency.
Tunable single-longitudinal-mode narrow linewidth Brillouin fiber laser based on PT symmetry
Authors: Tao Liuyuan , Wang Fei , Xia Guangqiong , Wu Zhengmao
Published: April 2023

A tunable single-longitudinal-mode (SLM) narrow linewidth Brillouin fiber laser based on parity-time (PT) symmetry is proposed and experimentally demonstrated. In the proposed scheme, the dual selecting-mode mechanism is employed to achieve the SLM operation. The first, a narrow-band gain curve induced by stimulated Brillouin scattering (SBS) can be acted as a filter for selecting mode preliminary in the fiber ring cavity. The second, a PT-symmetric structure is formed by using a Sagnac loop, in which by adjusting a single polarization controller, the PT symmetry can be broken, resulting in the SLM oscillation. The SBS effect can be further beneficial to the linewidth narrowing. Using the proposed scheme, the SLM lasing with an optical signal to noise ratio of 50.1 dB and an ultra-narrow linewidth of 300 Hz at 1547.90 nm is obtained. Compared with the original linewidth of pump laser, the linewidth-reduction ratio can be up to 680 times. The available wavelength ranges from 1528.4 to 1563.4 nm, covering 35 nm. The key advantage of the proposed laser is that by constructing a simple Sagnac loop, the SLM selection based on PT symmetry and linewidth narrowing benefiting from SBS effect are accomplished simultaneously. Moreover, it is worth noting that the wavelength tunability is virtually unrestricted, only depending on the pump wavelength.
486 nm pulsed Nd:YLF laser with intracavity sum-frequency mixing
Authors: Zhang Jiale , Ma Jian , Lu Tingting , Zhu Xiaolei
Published: April 2023

An intracavity sum-frequency pulsed laser emitting at 486 nm was demonstrated in a combined cavity for two electro-optically Q-switched Nd:YLF fundamental lasers emitting at 908 nm and 1047 nm respectively. Pumped by two 806 nm LDs at 50 Hz repetition rate, while the intracavity pulse energy reached 6.25 mJ at 908 nm and 2.57 mJ at 1047 nm, maximum output pulse energy of 0.26 mJ at 486.4 nm wavelength was successfully achieved by intracavity sum-frequency. The corresponding spectral bandwidth was less than 0.08 nm, and the pulse width was about 11.8 ns. The peak power of the blue laser pulse was up to 21.8 kW, and the results provided a new blue pulsed laser source around 486 nm for ocean detection applications.