bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial Distribution of Secondary Forests by Age Group and Biomass Accumulation in the Brazilian Amazon
Authors: da Silva Gabriel M. , Adami Marcos , Galbraith David , Nascimento Rodrigo G. M. , Wang Yunxia , Shimabukuro Yosio E. , Emmert Fabiano
Published: May 2023

Secondary forests provide essential ecosystem services, especially in helping to mitigate climate change with the storage of carbon in the aboveground biomass of tree species. In this context, the present research aimed to analyze the spatial distribution of secondary forests and estimate the aboveground biomass accumulation of land cover of different ages in the state of Pará. The spatial patterns of the secondary forests in Pará state were evaluated with hot spot analysis algorithms using data from the TerraClass project for the 2004–2014 time period. The results showed that the spatial distribution of the secondary forests did not occur randomly in space, but suggested local geopolitical influences. The younger secondary forests had the most deforested areas during the study period. Approximately 5% of Pará had its secondary forests deforested in 2014. In general, the balance of the secondary forests was positive. The aboveground biomass accumulation differed according to the secondary forest ages during the study period as evaluated in two pilot areas. It was observed that the secondary forests > 10 years old in pilot area A had an average of 23% of old-growth forest aboveground biomass in the same area, while in pilot area B, the secondary forests > 10 years old had an average of 32.7% of old-growth forest aboveground biomass.
Resin Canal Traits Variation in Pinus spp. with Different Susceptibility to the Pine Wood Nematode
Authors: Rodríguez-García Aida , Martín Juan A. , Gil Luis , Menéndez-Gutiérrez María , Díaz Raquel
Published: May 2023

Different studies have emphasized the influence of resin canal traits in the susceptibility of pine trees to the pine wood nematode (PWN) Bursaphelenchus xylophilus. Resin canals can facilitate the PWN migration through the stem and are involved in the accumulation of volatile terpenes in the xylem in response to the pathogen, inducing tracheid embolisms. In this work, we conducted a PWN inoculation experiment under greenhouse conditions to investigate the anatomical traits of constitutive resin canals among seven Pinus species with different degrees of susceptibility to the PWN: P. canariensis, P. halepensis, P. pinea and P. taeda were grouped into a ‘low-susceptible group’, and P. pinaster, P. radiata, and P. sylvestris were grouped into a ‘high-susceptible group’. The high-susceptible group presented higher xylem radial growth, wider constitutive canals in the cortex, lower frequency of constitutive canals in the cortex, and smaller constitutive canals in the xylem than the low-susceptible group. The size of constitutive cortical canals was positively related to the number of seedlings colonized by the PWN, suggesting that wider canals facilitated migration. The inoculation of the PWN increased the frequency and diminished the mean area of canals in the xylem, and the high-susceptible group showed more frequency of induced xylem canals than the low-susceptible group. Additionally, the high-susceptible group presented larger radial growths in the xylem than the low-susceptible group. These results suggest a role of resin canal traits on Pinus spp. susceptibility to the PWN. Nevertheless, the high interspecific variability found in these traits within each susceptibility group evidences the importance of other factors in the susceptibility to the PWN.
Developments on Core Collections of Plant Genetic Resources: Do We Know Enough?
Authors: Gu Rui , Fan Shaohui , Wei Songpo , Li Jiarui , Zheng Shihui , Liu Guanglu
Published: May 2023

The core collection is a small subset that minimizes genetic redundancy while preserving the maximum genetic diversity of the entire population. Research on the core collection is crucial for the efficient management and utilization of germplasm resources. In this paper, the concept of the core collection and the research progress of its construction have briefly been summarized. Subsequently, some perspectives have been proposed in this research field for the near future. Four novel opinions have been presented, (1) the effective integration of multiple data types and accurate phenotyping methods need to be focused on; (2) the sampling strategy and bioinformatics software should be given attention; (3) the core collection of afforestation tree and bamboo species, with a wide natural distribution range and a large planting area, need to be carried out as soon as possible; (4) we should place a high priority on the study of genes discoveries and utilize these with a rapid, precise and high-throughput pattern based on re-sequencing technology. This paper provides a theoretical and technological reference for further study and the application of the plant core collection.
Damages of Skidder and Oxen Logging to Residual Trees in Uneven-Aged Mixed Forest
Authors: Knežević Jelena , Musić Jusuf , Halilović Velid , Avdagić Admir
Published: May 2023

The negative influence of timber harvesting on the forest environment is reflected through damage to the residual trees, regeneration, and forest soil. Considering that skidding, a popular extraction method, can cause substantial and severe damage to the remaining stand, the aim of this research was to determine damage to residual trees during skidding by an LKT 81T cable skidder, including oxen bunching. The research was conducted in eastern Bosnia and Herzegovina, in an uneven-aged mixed fir (Abies alba Mill.) and spruce (Picea abies L.) forest with pine (Pinus sylvestris L.) on limestone soils. Tree felling was conducted using a Husqvarna 372 XP chainsaw. Extraction operations caused damage to 6.31% of the residual trees in the stand. The most damage was “removed bark” (65.34%) and occurred on the lower parts of the tree, the butt end (55.11%) and root collar (32.39%). The average size of the damage was 197.08 cm2. A statistically significant correlation was found between the damage position and the diameter at the breast height (p < 0.05) and the damage position and damage size (p < 0.01) by Spearman correlation analysis. The conducted analysis by the chi-squared test showed that there is a statistically significant difference in the proportion of damage for trees with different distances to the nearest skid road (p = 0.0487), but the share of damaged trees did not decrease by increasing the distance from the skid road.
Daily Vibration Exposure in the Context of State and European Legislature: A Case Study among Chainsaw Operators in Croatia
Authors: Bačić Marin , Pandur Zdravko , Šušnjar Marijan , Šporčić Mario , Landekić Matija
Published: May 2023

The Ordinance on Occupational Safety and Health in Forestry proposes no more than 4 h of effective chainsaw work daily, while EU Directive 2002/44/EC proposes an EAV of 2.5 m/s2, and an ELV of 5 m/s2. The aim of this paper was to compare and assess the viability of the proposed restrictions. A case study in Croatia including 91 felled and processed trees, a detailed time study, and vibration magnitude measuring on European beech wet wood in compliance with ISO 5349-1:2001 and ISO 5349-2:2001 standards were performed. The results implied that tree species, processing method, and DBH have no influence on the time structure of working hours. Using bigger and more powerful chainsaws resulted in higher A(8) values; it was also noted that the right hand is more exposed. On average, none of the observed chainsaws exceeded 5 m/s2 of A(8). It can be concluded that state legislature, which allows a maximum of 4 h of chainsaw work a day, is appropriately protecting chainsaw workers from vibration exposure, but is also obsolete (1986) as it only uses the time limit. In contrast, European legislature requires a methodical approach to A(8) calculation and leaves room for individual evaluation of specific chainsaw work, which opens up possibilities of extending or shortening some chainsaw operations.
Interacting with the Artificial Intelligence (AI) Language Model ChatGPT: A Synopsis of Earth Observation and Remote Sensing in Archaeology
Authors: Agapiou Athos , Lysandrou Vasiliki
Published: May 2023

In this communication we aim to provide an overview of Earth observation and remote sensing in archaeology following a non-traditional literature review approach, that is, investigating recent developments in artificial intelligence (AI) and language models. Towards this direction, the generative pre-trained transformer (ChatGPT) language model was used to extract relevant information. The ChatGPT language model—recently released by OpenAI—appears to provide an alternative way for retrieving comprehensive information for various thematic topics. ChatGPT is currently operated on a beta version by millions of users worldwide, free of access for a limited period. In this study, specific queries related to Earth observation and remote sensing in archaeology were made by the authors to the ChatGPT. Innovations and limitations are discussed, while a comparison with traditional bibliographic analysis is performed.
Charging Complicity in Abuses, Ignoring Beneficial Engagement: How American Conservatives Secured the Blocking of U.S. Funds for the UNFPA by Misrepresenting the UN’s Efforts to Reform China’s One-Child Policy
Authors: Yao Guigui , Hoff Derek , Wyman Robert J.
Published: May 2023

We describe a key moment during the world’s attempt to come to terms with enormously expanding populations. China was an extreme case, both in the magnitude of its population explosion and in its government’s control of reproduction through the One-Child Policy (OCP). The U.S. had been a founder and the main financial supporter of The United Nations Population Fund (UNFPA). Starting in 1998, UNFPA’s program in China attempted to move the OCP away from two decades of coercive family planning and toward acceptance of the women’s rights–centered global consensus that emerged from the 1994 Cairo Conference on Population and Development. In 2001, a conservative U.S. organization, the Population Research Institute, claimed to have gathered evidence of UNFPA’s involvement in Chinese coercion. Although several investigations, including one sent by President George W. Bush himself, refuted this evidence, and UNFPA had used no U.S. funds in China, conservative political power was sufficient to cause President George W. Bush to eliminate all U.S. funding for UNFPA’s activities everywhere in the world. Ironically, this period was exactly when the UNFPA project had shown that coercion was unnecessary. China eventually followed the UNFPA’s lead, liberalizing and eventually ending the OCP.
Mass Mortality of Shallow-Water Temperate Corals in Marine Protected Areas of the North Aegean Sea (Eastern Mediterranean)
Authors: Antoniadou Chryssanthi , Pantelidou Martha , Skoularikou Maria , Chintiroglou Chariton Charles
Published: May 2023

Coral mortality is a global phenomenon of increasing magnitude, correlated with climate change. Prolonged marine heatwaves have particularly affected the north Aegean Sea in summer 2021, threatening shallow-water stony corals, such as Balanophyllia europaea and Cladocora caespitosa. To assess their population status, ten coastal, rocky-bottom stations dispersed in Natura 2000 sites of Chalkidiki (north Aegean) were surveyed using non-destructive techniques in autumn 2021. At each station, corals’ abundance was estimated in situ, by counting the number of B. europaea polyps within randomly placed 50 × 50 cm quadrats, and the number of C. caespitosa colonies along three replicate belt transects 1 × 10 m. The status of corals was qualitatively assigned as healthy, bleached (partially or complete), or in necrosis (partial or complete). B. europaea was found in 80% of stations; in total, 58.17% of the coral specimens were affected by necrosis. C. caespitosa was found in 30% of stations; in total, 27.49% of the coral colonies were partially bleached and 11.32% in necrosis. Another nine sessile invertebrates (sponges, bivalves, and ascidians) were observed in necrosis. These results highlight the need to establish monitoring programs on vulnerable sessile invertebrate populations along the Aegean Sea to assess climate change impacts.
Insomnia and Death Anxiety: A Theoretical Model with Therapeutic Implications
Authors: Watson Nathaniel F.
Published: May 2023

Insomnia is common, growing in prevalence [...]
Three-Dimensional Trajectory Tracking of AUV Based on Nonsingular Terminal Sliding Mode and Active Disturbance Rejection Decoupling Control
Authors: Zhang Wei , Wu Wenhua , Li Zixuan , Du Xue , Yan Zheping
Published: May 2023

This paper presents a nonsingular terminal sliding mode and active disturbance rejection decoupling control (NTSM-ADRDC) scheme for the three-dimensional (3D) trajectory tracking of autonomous underwater vehicles (AUV). Firstly, the AUV model is decoupled into five independent single input–single output (SISO) channels using ADRDC technology. Secondly, the NTSM-ADRDC controller is designed. The linear extended state observer (LESO) is used to observe the AUV state variables, and estimate the total disturbance of the system. In addition, to improve the system error convergence rate, the combination of exponential reaching rate and NTSM constitutes a nonlinear states error feedback control law for the controller. Finally, the stability of the proposed control law is proved using the Lyapunov theory. The simulation results demonstrate the effectiveness and robustness of the designed NTSM-ADRDC trajectory tracking approach.
New Records of the Copidognathus gibbus Group (Acari, Halacaridae) from Korea, with Descriptions of C. levicostatus n. sp. and C. vicinus
Authors: Lee Jimin , Shin Jong Hak , Chang Cheon Young
Published: May 2023

Two marine halacarids, Copidognathus levicostatus n. sp. and C. vicinus Bartsch, 1997, belonging to the C. gibbus group, have been recorded based on both sexes from the microhabitat of intertidal and sublittoral rocks on the coast of South Korea. Copidognathus levicostatus n. sp. Is characterized by a combination of features, as follows: the absence of areolae with rosette pores on all dorsal and ventral plates, the presence of a short frontal process, a pair of costae with raised narrow ribs on the posterior dorsal plate, the partial fusion of the anterior epimeral plate and genitoanal plate in both sexes, and three pairs of perigenital setae in the male. The Korean specimens of C. vicinus Bartsch, 1997 agree well with the original description from Hong Kong, except for the lateral claws bearing a comb. This study provides detailed (re)descriptions of the morphological characteristics of the two Korean halacarid species, C. levicostatus n. sp. and C. vicinus, based on illustrations and scanning electron microscope photomicrographs. Additionally, we present a dichotomous key for known Copidognathus species in Korean waters, accompanied by a brief comment on their occurrence in various microhabitats, especially their habitat preferences for geniculate and non-geniculate red coralline algae.
Shoreline Changes from Erosion and Sea Level Rise with Coastal Management in Phuket, Thailand
Authors: Nidhinarangkoon Pattrakorn , Ritphring Sompratana , Kino Kanon , Oki Taikan
Published: May 2023

Phuket, the study area of this work with 33 sandy beaches, provides about 15% of the nation’s gross domestic product from the tourism industry. Many factors cause shoreline changes affecting beach areas, such as seasonal erosion and rising sea levels. In this study, shoreline position was the key parameter for evaluating shoreline changes. The CoastSat open-source software was selected to analyze the shoreline changes using a publicly available satellite imagery API. The future shoreline recession was projected using the Bruun rule integrated with field observation data and sea level rise scenarios from Coupled Model Intercomparison Project Phase 6 (CMIP6). The result indicated that eight of the study site’s locations were under mild erosion from 2013 to 2021. The average shoreline change varied between −4.10 and 5.47 m/year. The projection of future beach loss due to sea level rise found that 20 beaches and 32 beaches will be lost entirely under SSP1 2.6 and SSP5 8.5, respectively. Beach morphology is influenced by human-induced activities, such as coastal urbanization and the development of structures along the coast. This study discusses the effectiveness of the present coastal protection structure with data from field observations and suggests possible future management strategies.
Dose Land Negotiation Policy Promote or Suppress Hidden Debts of Local Governments?
Authors: Zhao Yinglan , Xu Jingwen , Feng Chen , Gong Chi
Published: May 2023

Using panel data from 275 prefecture-level cities in China spanning from 2003 to 2019, this paper employs the multiperiod difference-in-differences method to empirically analyze the policy effect of land negotiation policy on local governments’ hidden debt. The paper also investigates the influence mechanisms of land finance, budget soft constraints, fiscal decentralization and government competition. The empirical results reveal that: (1) Land negotiations promote the expansion of local governments’ hidden debt, which is counterproductive to the sustainable development of government finances. (2) The impact of land negotiation policy on local government’s hidden debt is transmitted via its effects on land finance. (3) The greater the degree of soft budget constraint and the degree of government competition, the less the expansion effect of land negotiations on the hidden debt of the government. The greater the degree of fiscal decentralization, the greater the expansion effect of land negotiations on the government’s hidden debt. (4) Land negotiation promotes the expansion of hidden debt in eastern China and inhibits it in central China, with no significant effect observed in western China. (5) Cities with larger urban scale and higher economic development levels experience stronger effects from land negotiation policies. Therefore, it is imperative to deepen the land negotiation system further, develop policy indicators and feedback mechanisms tailored to local conditions, and introduce a multiparty supervision system to enhance implementation of the land negotiation system.
Capacity Assessment of Urban Green Space for Mitigating Combined Sewer Overflows in the Tokyo Metropolitan Area
Authors: Ogawa Ryohei , Zhang Ye , Theng Vouchlay , Guo Zhongyu , Wang Manna , Yoshimura Chihiro
Published: May 2023

Among the countermeasures against combined sewer overflow (CSO), urban green space (UGS) has been proven effective. However, few studies have examined the effects of UGS on CSO at the municipal scale. Therefore, this study aimed to develop a novel method for estimating the relation of the area of UGS to CSO based on a case study in the Tokyo metropolitan area, which includes 10 sewersheds. This method integrates surface runoff modeling, sewer network analysis, and response analysis for estimating CSO and its response to the UGS proportion in each sewershed. This method is based on public data of topographic features, land-related data, and rainfall characteristics. Specifically, the CSO discharge is estimated to be the difference between the rainwater inflow to a terminal treatment plant and the maximum capacity of the sewer systems in each sewershed. The results revealed that the amount of CSO increases exponentially with the intensity of rainfall. In addition, a response analysis showed that the increase in UGS proportion would mitigate CSO in all sewersheds, particularly in the case where the UGS proportion increased from 5% to 10%. Overall, the present method allows us to estimate CSO in relation to rainfall pattern and the distribution of UGS in a sewershed without actual CSO records.
Natural Hazard Characterisation in the Arribes del Duero Natural Park (Spain)
Authors: Merchán Leticia , Martínez-Graña Antonio Miguel , Nieto Carlos E. , Criado Marco
Published: May 2023

Natural disasters have been significantly affecting the natural and artificial environment for decades. For this reason, it is necessary to carry out adequate territorial planning in order to predict and mitigate possible natural risks in areas of great environmental value and interest, which is the case of the Arribes del Duero Natural Park. In order to achieve this, geotechnical mapping should be carried out followed by hazard mapping, taking into account the lithological, hydrogeological and geomorphological characteristics and, in addition, the real erosion rates. The results indicate that, in the study area, there are three areas with different geotechnical characteristics, classified according to their lithological, geomorphological and hydrological characteristics. In terms of hazards, there are five zones: with hydrological problems; lithological and geomorphological problems; geomorphological and hydrological problems; geomorphological and lithological problems; and geotechnical problems. Finally, it can be concluded that geotechnical mapping enables us to delimit areas of recommendations and limitations of use in terms of construction activities which, together with natural hazard mapping, will be very useful in the preparation of risk mapping for land-use planning.
Colorectal Cancer—The “Parent” of Low Bowel Obstruction
Authors: Grigorean Valentin Titus , Erchid Anwar , Coman Ionuţ Simion , Liţescu Mircea
Published: May 2023

Introduction: Despite the improvement of early diagnosis methods for multiple pathological entities belonging to the digestive tract, bowel obstruction determined by multiple etiologies represents an important percentage of surgical emergencies. General data: Although sometimes obstructive episodes are possible in the early stages of colorectal cancer, the most commonly installed intestinal obstruction has the significance of an advanced evolutionary stage of neoplastic disease. Development of Obstructive Mechanism: The spontaneous evolution of colorectal cancer is always burdened by complications. The most common complication is low bowel obstruction, found in approximately 20% of the cases of colorectal cancer, and it can occur either relatively abruptly, or is preceded by initially discrete premonitory symptoms, non-specific (until advanced evolutionary stages) and generally neglected or incorrectly interpreted. Success in the complex treatment of a low neoplastic obstruction is conditioned by a complete diagnosis, adequate pre-operative preparation, a surgical act adapted to the case (in one, two or three successive stages), and dynamic postoperative care. The moment of surgery should be chosen with great care and is the result of the experience of the anesthetic-surgical team. The operative act must be adapted to the case and has as its main objective the resolution of intestinal obstruction and only in a secondary way the resolution of the generating disease. Conclusions: The therapeutic measures adopted (medical-surgical) must have a dynamic character in accordance with the particular situation of the patient. Except for certain or probably benign etiologies, the possibility of colorectal neoplasia should always be considered, in low obstructions, regardless of the patient’s age.
Biogas and Syngas Production from Sewage Sludge: A Sustainable Source of Energy Generation
Authors: Enebe Nwabunwanne Lilian , Chigor Chinyere Blessing , Obileke KeChrist , Lawal Mohammed Shariff , Enebe Matthew Chekwube
Published: May 2023

Sewage sludge to energy conversion is a sustainable waste management technique and a means of militating against the environmental concerns associated with its disposal. Amongst the various conversion technologies, anaerobic digestion and gasification have been identified as the two most promising. Therefore, this study is focused on a detailed evaluation of the anaerobic digestion and gasification of sewage sludge for energy production. Moreover, the key challenges hindering both technologies are discussed, as well as the practical measures for addressing them. The applicable pretreatment measures for efficient transformation into valuable energy vectors were further evaluated. Specifically, the study evaluated various properties of sewage sludge in relation to gasification and anaerobic digestion. The findings showed that a high ash content in sewage sludge results in sintering and agglomeration, while a high moisture content promotes tar formation, which has been identified as one of the key limitations of sewage sludge gasification. More importantly, the application of pretreatment has been shown to have some beneficial features in promoting organic matter decomposition/degradation, thereby enhancing biogas as well as syngas production. However, this has additional energy requirements and operational costs, particularly for thermal and mechanical methods.
Temperature Drift Compensation for Four-Mass Vibration MEMS Gyroscope Based on EMD and Hybrid Filtering Fusion Method
Authors: Li Zhong , Cui Yuchen , Gu Yikuan , Wang Guodong , Yang Jian , Chen Kai , Cao Huiliang
Published: May 2023

This paper presents an improved empirical modal decomposition (EMD) method to eliminate the influence of the external environment, accurately compensate for the temperature drift of MEMS gyroscopes, and improve their accuracy. This new fusion algorithm combines empirical mode decomposition (EMD), a radial basis function neural network (RBF NN), a genetic algorithm (GA), and a Kalman filter (KF). First, the working principle of a newly designed four-mass vibration MEMS gyroscope (FMVMG) structure is given. The specific dimensions of the FMVMG are also given through calculation. Second, finite element analysis is carried out. The simulation results show that the FMVMG has two working modes: a driving mode and a sensing mode. The resonant frequency of the driving mode is 30,740 Hz, and the resonant frequency of the sensing mode is 30,886 Hz. The frequency separation between the two modes is 146 Hz. Moreover, a temperature experiment is performed to record the output value of the FMVMG, and the proposed fusion algorithm is used to analyse and optimise the output value of the FMVMG. The processing results show that the EMD-based RBF NN+GA+KF fusion algorithm can compensate for the temperature drift of the FMVMG effectively. The final result indicates that the random walk is reduced from 99.608°/h/Hz1/2 to 0.967814°/h/Hz1/2, and the bias stability is decreased from 34.66°/h to 3.589°/h. This result shows that the algorithm has strong adaptability to temperature changes, and its performance is significantly better than that of an RBF NN and EMD in compensating for the FMVMG temperature drift and eliminating the effect of temperature changes.
A Methodology for Enhancing SSVEP Features Using Adaptive Filtering Based on the Spatial Distribution of EEG Signals
Authors: Wang Shengyu , Ji Bowen , Shao Dian , Chen Wanru , Gao Kunpeng
Published: May 2023

In this paper, we propose a classification algorithm of EEG signal based on canonical correlation analysis (CCA) and integrated with adaptive filtering. It can enhance the detection of steady-state visual evoked potentials (SSVEPs) in a brain–computer interface (BCI) speller. An adaptive filter is employed in front of the CCA algorithm to improve the signal-to-noise ratio (SNR) of SSVEP signals by removing background electroencephalographic (EEG) activities. The ensemble method is developed to integrate recursive least squares (RLS) adaptive filter corresponding to multiple stimulation frequencies. The method is tested by the SSVEP signal recorded from six targets by actual experiment and the EEG in a public SSVEP dataset of 40 targets from Tsinghua University. The accuracy rates of the CCA method and the CCA-based integrated RLS filter algorithm (RLS-CCA method) are compared. Experiment results show that the proposed RLS-CCA-based method significantly improves the classification accuracy compared with the pure CCA method. Especially when the number of EEG leads is low (three occipital electrodes and five non occipital electrodes), its advantage is more significant, and accuracy reaches 91.23%, which is more suitable for wearable environments where high-density EEG is not easy to collect.
Investigation of the Gate Degradation Induced by Forward Gate Voltage Stress in p-GaN Gate High Electron Mobility Transistors
Authors: Chae Myeongsu , Kim Hyungtak
Published: May 2023

In this work, we investigated the degradation of the p-GaN gate stack induced by the forward gate voltage stress in normally off AlGaN/GaN high electron mobility transistors (HEMTs) with Schottky-type p-GaN gate. The gate stack degradations of p-GaN gate HEMTs were investigated by performing the gate step voltage stress and the gate constant voltage stress measurements. In the gate step voltage stress test, the positive and negative shifts of threshold voltage (VTH) depended on the range of the gate stress voltage (VG.stress) at room temperature. However, the positive shift of VTH in the small gate stress voltage was not observed at 75 and 100 °C and the negative shift of VTH was started from a lower gate voltage at a high temperature compared to room temperature. In the gate constant voltage stress test, the gate leakage current increased with three steps in the off-state current characteristics as the degradation progressed. To investigate the detailed breakdown mechanism, we measured the two terminal currents (IGD and IGS) before and after the stress test. The difference between the gate–source current and the gate–drain current in the reverse gate bias indicated that the increase of the leakage current was attributed to the degradation between the gate and the source while the drain side was not affected.
Engineered Vasculature for Cancer Research and Regenerative Medicine
Authors: Nguyen Huu Tuan , Peirsman Arne , Tirpakova Zuzana , Mandal Kalpana , Vanlauwe Florian , Maity Surjendu , Kawakita Satoru , Khorsandi Danial , Herculano Rondinelli , Umemura Christian , Yilgor Can , Bell Remy , Hanson Adrian , Li Shaopei , Nanda Himansu Sekhar , Zhu Yangzhi , Najafabadi Alireza Hassani , Jucaud Vadim , Barros Natan , Dokmeci Mehmet Remzi , Khademhosseini Ali
Published: May 2023

Engineered human tissues created by three-dimensional cell culture of human cells in a hydrogel are becoming emerging model systems for cancer drug discovery and regenerative medicine. Complex functional engineered tissues can also assist in the regeneration, repair, or replacement of human tissues. However, one of the main hurdles for tissue engineering, three-dimensional cell culture, and regenerative medicine is the capability of delivering nutrients and oxygen to cells through the vasculatures. Several studies have investigated different strategies to create a functional vascular system in engineered tissues and organ-on-a-chips. Engineered vasculatures have been used for the studies of angiogenesis, vasculogenesis, as well as drug and cell transports across the endothelium. Moreover, vascular engineering allows the creation of large functional vascular conduits for regenerative medicine purposes. However, there are still many challenges in the creation of vascularized tissue constructs and their biological applications. This review will summarize the latest efforts to create vasculatures and vascularized tissues for cancer research and regenerative medicine.
Mixed Convection Hybrid Nanofluid Flow Induced by an Inclined Cylinder with Lorentz Forces
Authors: Sohut Farizza Haniem , Khan Umair , Ishak Anuar , Soid Siti Khuzaimah , Waini Iskandar
Published: May 2023

Hybrid nanofluids may exhibit higher thermal conductivity, chemical stability, mechanical resistance and physical strength compared to regular nanofluids. Our aim in this study is to investigate the flow of a water-based alumina-copper hybrid nanofluid in an inclined cylinder with the impact of buoyancy force and a magnetic field. The governing partial differential equations (PDEs) are transformed into a set of similarity ordinary differential equations (ODEs) using a dimensionless set of variables, and then solved numerically using the bvp4c package from MATLAB software. Two solutions exist for both buoyancy opposing (λ < 0) and assisting (λ > 0) flows, whereas a unique solution is found when the buoyancy force is absent (λ = 0). In addition, the impacts of the dimensionless parameters, such as curvature parameter, volume fraction of nanoparticles, inclination angle, mixed convention parameter, and magnetic parameter are analyzed. The results of this study compare well with previously published results. Compared to pure base fluid and regular nanofluid, hybrid nanofluid reduces drag and transfers heat more efficiently.
Applications and Future Prospects of Micro/Nanorobots Utilizing Diverse Biological Carriers
Authors: Lv Yu , Pu Ruochen , Tao Yining , Yang Xiyu , Mu Haoran , Wang Hongsheng , Sun Wei
Published: May 2023

Targeted drug delivery using micro-nano robots (MNRs) is a rapidly advancing and promising field in biomedical research. MNRs enable precise delivery of drugs, addressing a wide range of healthcare needs. However, the application of MNRs in vivo is limited by power issues and specificity in different scenarios. Additionally, the controllability and biological safety of MNRs must be considered. To overcome these challenges, researchers have developed bio-hybrid micro-nano motors that offer improved accuracy, effectiveness, and safety for targeted therapies. These bio-hybrid micro-nano motors/robots (BMNRs) use a variety of biological carriers, blending the benefits of artificial materials with the unique features of different biological carriers to create tailored functions for specific needs. This review aims to give an overview of the current progress and application of MNRs with various biocarriers, while exploring the characteristics, advantages, and potential hurdles for future development of these bio-carrier MNRs.
Neurotoxicity of Silver Nanoparticles and Non-Linear Development of Adaptive Homeostasis with Age
Authors: Antsiferova Anna A. , Kopaeva Marina Yu. , Kochkin Vyacheslav N. , Reshetnikov Alexander A. , Kashkarov Pavel K.
Published: May 2023

For the first time in the world, the behavioral functions of laboratory mammals exposed to silver nanoparticles were studied with regard to age. Silver nanoparticles coated with polyvinylpyrrolidone with a size of 8.7 nm were used in the present research as a potential xenobiotic. Elder mice adapted to the xenobiotic better than the younger animals. Younger animals demonstrated more drastic anxiety than the elder ones. A hormetic effect of the xenobiotic in elder animals was observed. Thus, it is concluded that adaptive homeostasis non-linearly changes with age increase. Presumably, it may improve during the prime of life and start to decline just after a certain stage. This work demonstrates that age growth is not directly conjugated with the organism fading and pathology development. Oppositely, vitality and resistance to xenobiotics may even improve with age at least until the prime of life.
Ultra-Broadband Solar Absorber and High-Efficiency Thermal Emitter from UV to Mid-Infrared Spectrum
Authors: Wu Fuyan , Shi Pengcheng , Yi Zao , Li Hailiang , Yi Yougen
Published: May 2023

Solar energy is currently a very popular energy source because it is both clean and renewable. As a result, one of the main areas of research now is the investigation of solar absorbers with broad spectrum and high absorption efficiency. In this study, we create an absorber by superimposing three periodic Ti-Al2O3-Ti discs on a W-Ti-Al2O3 composite film structure. We evaluated the incident angle, structural components, and electromagnetic field distribution using the finite difference in time domain (FDTD) method in order to investigate the physical process by which the model achieves broadband absorption. We find that distinct wavelengths of tuned or resonant absorption may be produced by the Ti disk array and Al2O3 through near-field coupling, cavity-mode coupling, and plasmon resonance, all of which can effectively widen the absorption bandwidth. The findings indicate that the solar absorber’s average absorption efficiency can range from 95.8% to 96% over the entire band range of 200 to 3100 nm, with the absorption bandwidth of 2811 nm (244–3055 nm) having the highest absorption rate. Additionally, the absorber only contains tungsten (W), titanium (Ti), and alumina (Al2O3), three materials with high melting points, which offers a strong assurance for the absorber’s thermal stability. It also has a very high thermal radiation intensity, reaching a high radiation efficiency of 94.4% at 1000 K, and a weighted average absorption efficiency of 98.3% at AM1.5. Additionally, the incidence angle insensitivity of our suggested solar absorber is good (0–60°) and polarization independence is good (0–90°). These benefits enable a wide range of solar thermal photovoltaic applications for our absorber and offer numerous design options for the ideal absorber.
Polymeric and Paper-Based Lab-on-a-Chip Devices in Food Safety: A Review
Authors: Mitrogiannopoulou Athina-Marina , Tselepi Vasiliki , Ellinas Kosmas
Published: May 2023

Food quality and safety are important to protect consumers from foodborne illnesses. Currently, laboratory scale analysis, which takes several days to complete, is the main way to ensure the absence of pathogenic microorganisms in a wide range of food products. However, new methods such as PCR, ELISA, or even accelerated plate culture tests have been proposed for the rapid detection of pathogens. Lab-on-chip (LOC) devices and microfluidics are miniaturized devices that can enable faster, easier, and at the point of interest analysis. Nowadays, methods such as PCR are often coupled with microfluidics, providing new LOC devices that can replace or complement the standard methods by offering highly sensitive, fast, and on-site analysis. This review’s objective is to present an overview of recent advances in LOCs used for the identification of the most prevalent foodborne and waterborne pathogens that put consumer health at risk. In particular, the paper is organized as follows: first, we discuss the main fabrication methods of microfluidics as well as the most popular materials used, and then we present recent literature examples for LOCs used for the detection of pathogenic bacteria found in water and other food samples. In the final section, we summarize our findings and also provide our point of view on the challenges and opportunities in the field.
Dynamic Flow Control over Optical Properties of Liquid Crystal–Quantum Dot Hybrids in Microfluidic Devices
Authors: Bezrukov Artem , Galyametdinov Yury
Published: May 2023

In this paper, we report developing approaches to tuning the optical behavior of microfluidic devices by infusing smart hybrids of liquid crystal and quantum dots into microchannel confinement. We characterize the optical responses of liquid crystal–quantum dot composites to polarized and UV light in single-phase microflows. In the range of flow velocities up to 10 mm/s, the flow modes of microfluidic devices were found to correlate with the orientation of liquid crystals, dispersion of quantum dots in homogeneous microflows and the resulting luminescence response of these dynamic systems to UV excitation. We developed a Matlab algorithm and script to quantify this correlation by performing an automated analysis of microscopy images. Such systems may have application potential as optically responsive sensing microdevices with integrated smart nanostructural components, parts of lab-on-a-chip logic circuits, or diagnostic tools for biomedical instruments.
Development and Validation of a LabVIEW Automated Software System for Displacement and Dynamic Modal Parameters Analysis Purposes
Authors: El Dahr Reina , Lignos Xenofon , Papavieros Spyridon , Vayas Ioannis
Published: May 2023

The structural health monitoring (SHM) technique is a highly competent operative process dedicated to improving the resilience of an infrastructure by evaluating its system state. SHM is performed to identify any modification in the dynamic properties of an infrastructure by evaluating the acceleration, natural frequencies, and damping ratios. Apart from the vibrational measurements, SHM is employed to assess the displacement. Consequently, sensors are mounted on the investigated framework aiming to collect frequent readings at regularly spaced time intervals during and after being induced. In this study, a LabVIEW program was developed for vibrational monitoring and system evaluation. In a case study reported herein, it calculates the natural frequencies as well as the damping and displacement parameters of a cantilever steel beam after being subjected to excitation at its free end. For that purpose, a Bridge Diagnostic Inc. (BDI) accelerometer and a displacement transducer were parallelly mounted on the free end of the beam. The developed program was capable of detecting the eigenfrequencies, the damping properties, and the displacements from the acceleration data. The evaluated parameters were estimated with the ARTeMIS modal analysis software for comparison purposes. The reported response confirmed that the proposed system strongly conducted the desired performance as it successfully identified the system state and modal parameters.
Q1VA, a Synthetic Chalcone, Induces Apoptosis and Decreases Invasion on Primary Culture of Human Glioblastoma
Authors: Togni Anderson , Piermartiri Tetsade , de Souza Luiz Felipe Schmitz , Chiaradia Delatorre Louise Domeneghi , Nunes Ricardo José , Tasca Carla Inês , Nedel Cláudia Beatriz
Published: May 2023

Glioblastoma (GBM) is the most commonly occurring type of primary tumor of the central nervous system (CNS) and is considered the worst type of glioma. Despite the current standard treatment for newly diagnosed GBM, which involves surgery followed by chemotherapy with temozolomide (TMZ) and radiation therapy, the average survival time for patients with GBM is only about 15 months. This is due to GBM’s tendency to recur, its high proliferative rates, its ability to evade apoptosis, and its ability to invade healthy tissue. Therefore, it is crucial to explore new treatment options for GBM. This study investigated the potential anticancer activities of a new series of synthetic chalcones, which are natural compounds found in the biosynthesis of flavonoids in plants. Primary cell culture of glioblastoma (GBM1) from surgical resection was used to evaluate the effects of synthetic chalcones on viability, cell death, reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), cell cycle, and invasion. One chalcone, Q1VA (at concentrations of 10, 50, and 100 μM for 24 h) induced cytotoxicity by increasing apoptosis levels and depolarizing the mitochondrial membrane, as evidenced by a TMRE assay. Further analysis using the molecular fluorescent probe H2DCFDA indicated that the increased levels of reactive oxygen species (ROS) might be linked to altered mitochondrial membrane potential and cell death. Furthermore, viable cells were observed to be delayed in the cell cycle, primarily in the M phase, and the invasion process was reduced. The findings of this study indicate that Q1VA is a potential adjuvant therapeutic agent for GBM due to its significant antitumor effects. If its safety and efficacy can be confirmed in animal models, Q1VA may be considered for clinical trials in humans. However, additional research is required to determine the optimal dosage, treatment schedule, and potential side effects of Q1VA.
Model-Based Analysis of In Vivo Release Data of Levonorgestrel Implants: Projecting Long-Term Systemic Exposure
Authors: Kim Soyoung , Cicali Brian , Pressly Michelle , Da Silva Lais , Wendl Thomas , Vozmediano Valvanera , Schmidt Stephan , Cristofoletti Rodrigo
Published: May 2023

Levonorgestrel (LNG) is a progestin used in many contraceptive formulations, including subcutaneous implants. There is an unmet need for developing long-acting formulations for LNG. To develop long-acting formulations, release functions need to be investigated for LNG implant. Therefore, a release model was developed and integrated into an LNG physiologically-based pharmacokinetic (PBPK) model. Utilizing a previously developed LNG PBPK model, subcutaneous administration of 150 mg LNG was implemented into the modeling framework. To mimic LNG release, ten functions incorporating formulation-specific mechanisms were explored. Release kinetic parameters and bioavailability were optimized using Jadelle® clinical trial data (n = 321) and verified using two additional clinical trials (n = 216). The First-order release and Biexponential release models showed the best fit with observed data, the adjusted R-squared (R2) value is 0.9170. The maximum released amount is approximately 50% of the loaded dose and the release rate is 0.0009 per day. The Biexponential model also showed good agreement with the data (adjusted R2 = 0.9113). Both models could recapitulate observed plasma concentrations after integration into the PBPK simulations. First-order and Biexponential release functionality may be useful in modeling subcutaneous LNG implants. The developed model captures central tendency of the observed data as well as variability of release kinetics. Future work focuses on incorporating various clinical scenarios into model simulations, including drug-drug interactions and a range of BMIs.
Heat Transfer Characteristics of Oil-Based Drill Cuttings in Thermal Desorption Chambers
Authors: Wang Maoren , Liu Yucheng
Published: May 2023

Thermal desorption technologies have been extensively applied for the disposal of oil-based drill cuttings. Fluent-software-based phase changes in multiphase flow models within thermal desorption chamber temperature field simulations were examined to study the effects of oil-based drill cuttings fluid content and feed rates, nitrogen content, thermal desorption chamber length and diameter, and extraction tube position on the thermal desorption chamber and temperature field. Our results demonstrate that these factors had a considerable influence on the temperature field of the chamber, with the liquid content of the oil-based drill cuttings having the greatest influence. The heat transfer process was enhanced by appropriately increasing the diameter and length of the chamber and reasonably setting the extraction tube. When the chamber length was insufficient, there was a risk that the outlet temperature would be extremely low and the oil content of the residue would exceed the standard. The higher the feeding and nitrogen entering rates of the oil cuttings, the higher the liquid content of the oil cuttings and the lower the temperature in the chamber. Based on the heat transfer characteristics of the oil-based drill cuttings in the thermal desorption chamber, this study provides a theoretical basis for the design and application of oil-bearing cutting thermal desorption devices.