bluuebunny/crossref_metadata_2025 huggingface dataset:
Individual and interactive responses of woody plants' biomass and leaf traits to drought and shade
Authors: Wang Zhaoguo , Wang Chuankuan
Published: November 2022

Aim

While drought and shade are critical factors that determine seedling survival and growth, whether the responses of woody seedlings to drought are facilitated, aggravated or unaffected by shade remains uncertain.

Location

Global.

Time period

1993 to 2021.

Major taxa studied

Woody plants.

Methods

We compiled 58 studies (including 75 woody species from 33 families) in which water and light availability were simultaneously manipulated, and conducted a meta‐analysis on the acclimation and adaptive responses of biomass production and allocation and leaf traits to drought and/or shade.

Results

Shade alleviated the adverse impact of drought on photosynthesis (A) by decreasing stomatal limitation and photoinhibition, and increasing leaf relative water content, and thus facilitated biomass production, but shade aggravated the effect of drought on osmotic adjustment as evidenced by the lack of responses of osmotic potential at the full turgor and modulus elasticity at the maximum turgor to drought under shade. The effects of drought and shade on biomass allocation and specific leaf area were orthogonal. Biomass responses to drought and its interaction with shade were least responsive for drought‐tolerators, but the individual and interactive effects of shade and drought on most traits showed little dependence on shade tolerance. Drought–shade interaction increased root biomass and root mass fraction more for deciduous angiosperms than for evergreen angiosperms.

Main conclusions

Both shade and drought had negative impacts on biomass production and photosynthesis, but their interaction had positive effects that were less significant for drought‐tolerators and evergreen angiosperms. In contrast to shade, drought increased biomass allocation to roots, but shade and drought had orthogonal effects on biomass allocation and leaf morphology. These acclimation and adaptive responses of woody seedlings to drought and shade individually and interactively have important implications for predicting woody plant growth and distribution under global climate changes.
Mass Transfer from Mobile to Immobile Regions in Irregularly Shaped Micro‐Channels at Low Reynolds Number
Authors: Toyama Kizuki , Togi Fumina , Harada Shusaku
Published: November 2022

Transient mass transfer in rough‐walled micro‐channels was investigated experimentally. We conducted experiments using rough‐walled channels with various irregularities at small Reynolds number conditions. Mass transfer in the mainstream (mobile region) and dead water region (immobile region) were quantified using an image analysis technique based on absorption photometry. The experimental results showed that the solute dispersion in the mobile region was influenced by the irregular shape of the channel wall complicatedly. In contrast, mass transfer in the immobile region occurred by molecular diffusion independently on the wall roughness in our experimental conditions. The irregular shape of channel wall may enhance the mass transfer in mobile region by distorting the velocity distribution (Togi et al., 2020), while the solute redistribution to immobile region may suppress it in streamwise direction, just on a longer time scale. We developed a mass transfer model analogous to Mobile‐Immobile model (MIM model) proposed by previous studies. The concept of the model is the same as the previous study (Zhou et al., 2019) and the coefficients of the model describing mass transfer in each region were quantified from the experimental results as functions of geometric characteristics of the rough‐walled channel. In addition, mass transfer coefficient from mobile to immobile regions were derived mathematically based on the experimental results. The MIM model with the coefficients derived in this study well describes solute dispersion in variously shaped irregular channels quantitatively.
Gut microbiota in hypertensive patients with versus without obstructive sleep apnea
Authors: Lu Dasheng , Xu Shaodong , Dai Ping , Wu Lijuan , Zhang Hongxiang , Zhou Birong
Published: November 2022

We investigated the alteration of gut microbiota and the associated metabolic risks in hypertensive patients with obstructive sleep apnea (OSA) comorbidity. Fecal and blood samples were collected from 52 hypertensive patients, who were divided into three groups: A (controls, apnea‐hypopnea index[AHI] < 5, n = 15), B (mild OSA, 5 < AHI < 20, n = 17), and C (moderate‐to‐severe OSA, AHI > 20, n = 20). The composition of the gut microbiota was studied through 16s RNA sequencing of variable regions 3–4. Analysis of the results revealed that group C had a significant higher concentration of total cholesterol, low‐density lipoprotein, and IL‐1β compared with group A. The Shannon index showed that bacterial biodiversity was lower in OSA patients. At the phylum level, the ratio of Firmicutes to Bacteroidetes (F/B) was significantly higher in group C than in groups A and B. At the genus level, the relative abundance of short‐chain fatty acids (SCFA)‐producing bacteria (e.g., Bacteroides and Prevotella) was lower while the number of inflammation‐related bacteria (e.g., Lactobacillus) was increased in patients with OSA. We found that the IL‐1β level was negatively correlated with Bacteroidetes. The area under the receiver operating characteristic curve was .672 for F/B ratio in determining hypertensive patients with OSA. In patients with hypertension, OSA was associated with worse gut dysbiosis, as evidenced by decreased levels of short‐chain fatty acids‐producing bacteria and increased number of inflammation‐related bacteria. The differences in gut microbiota discriminate hypertensive patients with OSA from those without and may result in an enhanced inflammatory response and increase the risk of metabolic diseases.
Feasibility and evaluation of an emergency department‐based general practitioner streaming and treatment service
Authors: Aldus Clare , Pope Ian , Brainard Julii , Ruston Annmarie , Hughes Gareth , Everden Paul
Published: November 2022

Rationale

Offering a primary care service that can provide good quality primary care at emergency departments may reduce pressure on usual emergency department (ED) services.

Aims and Objectives

To evaluate the acceptability, satisfaction, and potential impacts of a co‐located primary care service at an emergency department.

Methods

This is a prospective feasibility study and service evaluation comprising a narrative summary of activity, satisfaction, well‐being, and safety, and comparisons of wait times for ED services by patient category (‘minor’, ‘majors’, ‘paediatric’ or ‘resus’) before and during the service operation. Patients and staff were asked using semistructured interview topic guides about service perception, well‐being, representation within 48 h, safety concerns, and/or satisfaction. Wait times for patient categories in usual ED care service were in secondary care electronic records. Pathway changes were captured under primary care electronic records.

Results

Approximately 96% of general practitioner streaming and treatment (GPST) patients were seen within 1 h. There was a statistically significant reduction in ED patients with minor injuries or illnesses waiting >4 h for admission or discharge ‘breaches’ during the 3 months that GPST was operating compared with the previous 3 months (p ≤ 0.005). Wait times for other ED services did not significantly improve. A total of 769 walk‐in patients received GPST consultation and 661 (86%) needed no further ED intervention. Fast discharge was a major determinant of patient satisfaction. No staff expressed dissatisfaction, but some suggested possible improvements in eligibility criteria and built environment design features.

Conclusion

Provision of GPST correlated with shorter waits for discharge from ED. Patient and staff experiences of GPST were positive.
The ontology of epidemics—A value‐dependent realist account of epidemics
Authors: Smart Benjamin T. H. , Combrink Herkulaas M. V.
Published: November 2022

Rationale

Charters and Heitman have recently argued that epidemic status is lost once the disease becomes ‘accepted into people's daily lives and routines, becoming endemic—domesticated—and accepted’. This is a normativist, subjectivist approach to epidemic classification; that is, it is both value‐laden, and dependent on the attitudes of the population. In this article, we argue for an alternative approach: a value‐dependent realist account of epidemic‐status.

Aims and Objectives

We aim to provide an ontological account of epidemics, with a particular focus on their endings. We do not attempt to present a historical account of previous epidemics, or why their endings were declared, but rather consider the theoretical underpinnings of such declarations. Further, our account is meant to be more prescriptive than descriptive; that is to say, even if public health does not currently view epidemics in the manner we advocate, the metaphysic of epidemics we advocate is, we believe, that which public health should ultimately endorse.

Method

The methodologies employed in this article are primarily those common to the philosophy of public health, philosophy of medicine and metaphysics; namely, conceptual analysis grounded by practical considerations.

Results

Charters and Heitman have recently argued that epidemic status is lost once the disease becomes ‘accepted into people's daily lives and routines, becoming endemic—domesticated—and accepted’. This is a normativist, subjectivist approach to epidemic classification; that is, it is both value‐laden, and dependent on the attitudes of the population. In this article, we argue for an alternative approach: a value‐dependent realist account of epidemic‐status.

Conclusion

To frame the argument we draw from complexity theory, arguing that human populations can be viewed as complex systems, and epidemic‐status as an emergent property of a complex system. We propose aggregating the normative standards relevant to labeling a disease as an epidemic, and use this as our indicator for both the beginning, and the end of epidemics. An epidemic ends, we argue, once the burden of disease drops below an objective but distinctly normative ‘epidemic threshold’.
Overexpressed LAMC2 promotes trophoblast over‐invasion through the PI3K/Akt/MMP2/9 pathway in placenta accreta spectrum
Authors: Wang Runfang , Liu Weifang , Zhao Jing , Liu Li , Li Shengxian , Duan Ya , Huo Yan
Published: November 2022

Background

Placenta accreta spectrum (PAS) is an ongoing major iatrogenic public health challenge with devastating obstetric complications, but its underlying molecular pathogenesis remains poorly illuminated. LAMC2 is reported to regulate tumor cells proliferation and invasion, yet has not been explored in placenta trophoblast cells. This study investigated LAMC2 expression and its contribution in the etiology of PAS.

Methods

Quantitative polymerase chain reaction, western blot, and immunohistochemistry were performed to detect the expression of LAMC2 in placentas. Cell proliferation, invasion, migration, and apoptosis were monitored by CCK8 assay, wound healing assay, transwell invasion assay, and flow cytometry assay. Western blot was conducted to confirm the pertinent proteins level of PI3K/Akt/MMP2/9 pathway in HTR8/SVneo cells.

Results

LAMC2 was predominantly expressed in placental villous syncytiotrophoblasts and cytotrophoblasts. LAMC2 mRNA and protein expression were substantially upregulated in placental tissues with PAS compared to those with pernicious placenta previa without PAS. LAMC2 overexpression eminently boosted HTR8/SVneo cells proliferation, invasion, and migration, but inhibited apoptosis, accompanied by elevated protein expression of MMP2, MMP9, and phosphorylated Akt (pAkt). Knockdown of LAMC2 yielded the converse results. Additionally, when treated with LY294002, the effects of LAMC2 overexpression on proliferation, migration, invasion, and apoptosis of HTR8/SVneo cells were abolished and concomitantly the elevated pAkt, MMP2, and MMP9 proteins induced by LAMC2 overexpression were eliminated.

Conclusion

Our study highlighted the involvement of LAMC2 in the pathogenesis of PAS by activating the PI3K/Akt/MMP2/9 signaling pathway to stimulate trophoblast over‐invasion. These findings provide a new target for the diagnosis and disease stratification of PAS.
Isolated dream‐enactment behaviours as a prodromal hallmark of rapid eye movement sleep behaviour disorder
Authors: Huang Bei , Zhang Jihui , Wang Jing , Chau Steven Wai Ho , Chan Joey Wing Yan , Yu Mandy Wai Man , Li Shirley Xin , Zhou Li , Mok Vincent , Wing Yun Kwok , Liu Yaping
Published: November 2022

Recurrent dream‐enactment behaviours (DEB) and rapid eye movement (REM) sleep without atonia (RSWA) are two diagnostic hallmarks of REM sleep behaviour disorder (RBD), a specific prodrome of α‐synucleinopathy. Whilst isolated RSWA (without DEB) was suggested as a prodrome of RBD, the implication of ‘isolated’ recurrent DEB remains under‐investigated. In this cross‐sectional study, we sought to investigate neurodegenerative markers amongst the first‐degree relatives (FDRs, aged >40 years) of patients with RBD who underwent clinical assessment for DEB, neurodegenerative markers, and video‐polysomnography assessment. Isolated recurrent DEB was defined as: (i) three or more episodes of DEB, (ii) had a DEB episode in the past 1 year, and (iii) subthreshold RSWA. We identified 29 FDRs (mean [SD] age 53.4 [8.3] years, 55.2% male) with isolated recurrent DEB and 98 age and sex‐matched FDRs as controls. Isolated DEB was associated with nightmare (27.6% versus 11.2%,p = 0.02), and the DEB group had a higher rate of current smoking (27.6% versus 3.1%,p = 0.006), type 2 diabetes mellitus (24.1% versus 10.2%,p = 0.003), anxiety disorder (24.1% versus 11.2%,p = 0.02), and constipation (hard lump of stool, 31.0% versus 7.1%,p < 0.001) than the control group. The present findings revealed that family relatives of patients with RBD with isolated recurrent DEB have increased risk of RBD and neurodegenerative features, which adds to the emerging data that isolated DEB is a prodromal feature of RBD and α‐synucleinopathy neurodegeneration.
Going the distance to test local adaptation in Coho salmon
Authors: Horn Rebekah L. , Narum Shawn R.
Published: November 2022

The mechanisms underlying local adaptation, where populations evolve traits that confer advantages to the local environment, is a central topic for understanding evolution in natural systems. Conservation goals for species at risk often include defining population boundaries by identifying gene diversity, genetic differentiation, and adaptation to local environments. In this issue of Molecular Ecology, Rougemont et al. (2022) combine genome‐wide SNP data with an extensive set of landscape variables to study the genomic mechanisms of local adaptation in the entire North American range of Coho salmon (Oncorhynchus kisutch), representing one of the largest studies of its kind. Migration distance, defined as the distance adult Coho salmon migrate from the ocean to their freshwater spawning ground, was found to be the primary factor driving local adaptation in this species. With climatic changes altering flow regimes and therefore the success of Coho salmon to return to spawning grounds, understanding environmental drivers and the genomic basis for migration is essential in the conservation of anadromous salmonids.
Well‐being, burnout and value fulfilment: Let us situate individuals within systems
Authors: Park Sophie , Bansal Aarti , Owen Emily C.
Published: November 2022

Bansal explores how systems‐based enquiry might productively shift focus from individual success or failure, to broader support of wellbeing and burnout prevention.
Global Cluster Analysis and Network Visualization in Musculoskeletal Pain Management: A Scientometric Mapping
Authors: Mei Fengyao , Li Jiao Jiao , Li Jiarong , Dong Shengjie , Li Zhichang , Xing Dan
Published: November 2022

Objective

Musculoskeletal pain is the most prominent clinical manifestation of more than 150 musculoskeletal disease conditions, and its effective long‐term management poses a great challenge to healthcare systems globally. For this, it is important to understand current research progress on musculoskeletal pain management. The purpose of the present study is to provide a comprehensive insight into the current state of research and global trends in musculoskeletal pain management.

Methods

Publications on musculoskeletal pain management from 1972 to 2021 were retrieved from the Science Citation Index‐Expanded (SCIE) database. Included articles were any article type related to aspects of musculoskeletal pain management, including etiology, mechanisms, epidemiology, treatment, outcomes, side effects, and patient compliance. Publication data were analyzed using bibliometric methods. The software VOSviewer was employed to perform bibliographic coupling, co‐authorship, co‐citation, and co‐occurrence analysis, and to visualize publication tendencies in musculoskeletal pain management.

Results

A total of 5475 articles were included in this study. The number of global publications on musculoskeletal pain management has escalated annually. Based on the number of publications and citations from the published literature, as well as the H‐index, the United States led global contributions in this area. The institutions making the highest contributions were the League of European Research Universities (LERU), the University of Sydney, and Harvard University. The journal BMC Musculoskeletal Disorders published the highest number of articles in this area. The published studies fall under six groups: “Prevention and rehabilitation,” “Etiology and diagnosis,” “Clinical study,” “Epidemiology,” “Mental health,” and “Education.” High‐quality primary studies and epidemiology are predicted to be the next prevailing topics in this field of research.

Conclusions

Based on current global trends, the number of publications on musculoskeletal pain management will continue to increase. Future studies will likely place more emphasis on high‐quality randomized controlled trials (RCTs) and epidemiological studies.
Evolution of flowering time genes in rice: From the paleolithic to the anthropocene
Authors: Osnato Michela
Published: November 2022

The evolutionary paths of humans and plants have crossed more than once throughout millennia. While agriculture contributed to the evolution of societies in prehistory, human selection of desirable traits contributed to the evolution of crops during centuries of cultivation. Among cereal crops, rice is currently grown around the globe and represents staple food for almost half of the world population. Over time, rice cultivation has expanded from subtropical to temperate regions thanks to artificial selection of mutants with impaired response to photoperiod. Additional regulatory mechanisms control flowering in response to diverse environmental cues, anticipating or delaying the floral transition to produce seeds in more favourable conditions. Nevertheless, the changing climate is threatening grain production because modern cultivars are sensitive to external fluctuations that go beyond their physiological range. One possibility to guarantee food production could be the exploitation of novel varieties obtained by crossing highly productive Asian rice with stress tolerant African rice. This review explores the genetic basis of the key traits that marked the long journey of rice cultivation from the end of the paleolithic to the anthropocene, with a focus on heading date. By 2050, will rice plants of the future flower in the outer space?
The paradoxical relationship between sense of power and creativity: Countervailing pathways and a boundary condition
Authors: Magni Federico , Gong Yaping , Li Jie (Kassie) , Pan Jingzhou , Zhou Mingjian
Published: November 2022

When sense of power helps or hinders creativity remains an unresolved question. Drawing upon the approach‐inhibition theory of power and its extensions, we integrate two different predictions into a dual‐pathway model, showing the paradoxical role that sense of power—one's perceived ability to influence others—plays in predicting creativity. Specifically, sense of power helps creativity through increased risk‐taking and simultaneously hinders it through reduced perspective taking. We further propose openness to experience as a moderator of the countervailing mechanisms, such that the positive path through risk‐taking is stronger and the negative path through perspective taking is weaker for individuals with higher (vs. lower) levels of openness. We test our hypotheses with three multisource and multi‐wave field studies (Study 1: n = 181 part‐time MBAs paired with peers; Study 2: n = 128 sales employees paired with store managers; Study 3: n = 153 sales employees paired with store managers). The results support our theoretical model, showing that sense of power and creativity are simultaneously connected positively through risk‐taking and negatively through perspective taking, and that the overall indirect effect of sense of power on creativity is more positive for individuals with higher (vs. lower) levels of openness to experience.
Nanocaging Rose Bengal to Inhibit Aggregation and Enhance Photo‐induced Oxygen Consumption†
Authors: Alvarez‐Lopez Constanza , Cavazos‐Elizondo Daniela , Heyne Belinda , Kochevar Irene E. , Aguirre‐Soto Alan
Published: November 2022

Photosensitized crosslinking of proteins in tissues has many medical applications including sealing wounds, strengthening tissues, and beneficially altering tissue properties. Rose Bengal (RB) is used most frequently as the photosensitizer but is not as efficient as would be desired for broad utilization in medicine. Aggregation of RB, at the high concentrations used for medical treatments, decreases the yield of singlet oxygen, which mediates protein crosslinking. We hypothesized that nanocages that sequester RB would inhibit self‐association, increasing photosensitization efficiency. We tested cucurbituril and cyclodextrin nanocages, demonstrating that hydroxypropyl‐functionalized cyclodextrins are most effective in inhibiting RB aggregation. For these RB/cyclodextrin solutions, we investigated the effect of nanocaging on the photobleaching and oxygen consumption kinetics under 530 nm LED light in aqueous phosphate‐buffered solutions. At 100 μm RB, the initial oxygen consumption rates increased by 58% and 80% compared with uncaged RB for the β and γ (2‐hydroxypropyl) cyclodextrins, respectively. For 1 mm RB, the enhancement in these rates was much greater, about 200% and 300%, respectively. In addition, at 1 mm RB these two cyclodextrins increased the RB photobleaching rate by ~20% and ~75%. These results suggest that nanocages can minimize RB aggregation and may lead to higher‐efficiency photo‐medical therapies.
Morphological characterization and pathogenicity of Colletotrichum aenigma and C. siamense causing anthracnose on Euonymus japonicus in Beijing, China
Authors: Tan Xiaoqian , Zhao Juan , Qiao Guanghang , Liu Juanjuan , Hsiang Tom , Yu Zhihe , Qin Wentao
Published: November 2022

Euonymus japonicus plays important roles in the process of urban landscape construction as an evergreen shrub. Anthracnose is an important limiting factor affecting the healthy growth of E. japonicus, seriously influencing improvement of urban landscape ecosystems. However, the Colletotrichum species associated with anthracnose on E. japonicus are unclear. In this study, diseased leaves of E. japonicus with typical anthracnose symptoms were collected in five nurseries in Beijing, China. Among 45 Colletotrichum isolates obtained, there were two distinct morphotypes, which were identified as C. aenigma or C. siamense by morphological characteristics and multilocus phylogenetic analysis. The growth rates of these two species were determined at different incubation temperatures, and the results showed that both species grew well at 10–35°C, particularly at 25 or 30°C, while C. aenigma isolates were adapted to high growth rates at a wider range of temperatures than C. siamense. Pathogenicity assays indicated that the two species showed varying degrees of pathogenicity on E. japonicus. Wounding was conducive to the pathogenicity of C. aenigma or C. siamense on E. japonicus either by inoculation with mycelial discs or conidial suspensions. This study presents the first report of C. aenigma causing anthracnose on E. japonicus worldwide and of C. siamense in north China causing anthracnose on E. japonicus. The morphological features of Colletotrichum spp. associated with anthracnose on E. japonicus were also compared in detail in this study. The findings provide a contribution to the prevention and control of anthracnose on E. japonicus by better understanding the species involved.
Locally initiated and designed innovation and potential reverse transfer through selective bricolage at threeMNCsubsidiaries in China
Authors: Hong Jacky F. L. , Snell Robin Stanley
Published: November 2022

Drawing on the concept of bricolage as ‘making do’ with and recombining limited resources for new purposes, our study analyzed how organization members in three MNC subsidiaries circumnavigated resource and market constraints to develop locally initiated and designed innovations in China. We developed two main contributions. First, the subsidiaries engaged selectively in bricolage, often combining it with ingénieuring, that is, formal, systematic methodologies, to bring innovations to fruition, and they could involve clients in the bricolage, through either convention‐based or familiarity‐based collaboration. The second contribution relates to reverse transfer of bricolage‐based innovations, which was especially challenging for the focal subsidiaries as they lacked global R&D mandates. Gaining HQ approval at the outset or early stages of the project, respecting the boundaries and regulations set by the HQ, establishing the pragmatic legitimacy of the solutions, and demonstrating the innovated product or service during an HQ visit appeared to be essential for reverse transfer.
Sputum basophils from allergic asthmatic patients do not express IL‐7Rα that is essential for TSLP signalling
Authors: Gao Sijia , Shi Yanbiao , Bai Ruixue , Li Hui , Ren Jinfeng , Chen Xinzhu , Hu Lang , Shi Zhixu , Zhao Shuli , Wang Hui
Published: November 2022

Basophils are crucial in regulating allergic reactions via immediate secretion of multiple mediators upon IgE‐induced degranulation. IL‐3 regulates the development and activation of human basophils while epithelial cytokine thymic stromal lymphopoietin (TSLP) is another key regulator for murine basophils. Despite association of increased TSLP with exaggerated basophil responses in oesophageal biopsies, the effects of TSLP in regulating human basophil degranulation and activation are under debate. In this study, we aimed to examine whether human basophils responded to TSLP by co‐expression of TSLP receptors, TSLPR and IL‐7Rα (CD127), upon in vitro activation and in sputum of allergic asthmatic patients. Flow cytometric analysis of fresh basophils from healthy controls revealed no detectable TSLPR and CD127. Further flow cytometric analysis of basophils from healthy controls in vitro stimulated by multiple established basophil modulators for 24 hours showed induction of TSLPR but not CD127 by IL‐3 (10 ng/ml), anti‐IgE (10 μg/ml) and C5a (50 ng/ml). One‐hour stimulation of basophils from allergic asthmatic patients and healthy controls by TSLP (50 ng/ml) with or without IL‐3 (10 ng/ml) and anti‐IgE (10 μg/ml) had no effect on induction of CD63+ degranulated basophils. Similarly, TSLP (50 ng/ml) with or without IL‐3 (10 ng/ml) and anti‐IgE (10 μg/ml) did not induce IL‐4 and IL‐13 production by basophils from healthy controls. Further ex vivo analysis revealed that sputum basophils from allergic asthmatic patients did not express CD127. We conclude that human basophils from healthy controls and allergic asthmatic patients do not respond to TSLP as lacking CD127.
The birth of Dolly and xenotransplantation 25 years on
Authors: Nottle Mark B. , Hawthorne Wayne J. , Cowan Peter J.
Published: November 2022

A number of reviews have been written recently celebrating the 25th anniversary of the birth of Dolly the cloned sheep and the effect this breakthrough has had on various fields of research. However, arguably the biggest impact Dolly has had is on the field of xenotransplantation, described here based on our own experience and that of others.
Batch Adsorption Studies of Natural Composite Hydrogel for Removal of Co(II) Ions
Authors: Marey A. , Ahmed Doaa F.
Published: November 2022

Innovative methods for handling industrial wastewater containing heavy metals has been receiving significant attention from researchers in recent years. Proper treatment of wastewater is compulsory to avoid the release of toxic heavy metal ions into water bodies. In this study, we developed a new adsorptive material, i.e., orange peel/acrylamide composite hydrogel for the removal of Co(II) ions from aqueous solution. The results showed that the adsorption of Co(II) by our hydrogen was well-fitted with the pseudo-second-order model. Its adsorption rate against Co(II) ions could reach up to 56 mg/g at pH 6. Further investigations are still needed to maximize the adsorption capacity of orange peel/acrylamide composite hydrogel.
An Alternative Form of the Equation of Motion for Constrained Structural and Mechanical Systems With Singular Mass Matrices
Authors: Udwadia Firdaus E. , Mogharabin Nami
Published: November 2022

This paper develops an alternative description of the general equation of motion for constrained mechanical systems with singular mass matrices. The formulation gives a new explicit equation of motion for such systems and provides a simple and elegant way to interpret the manner in which Nature orchestrates constrained motion, something that was not possible for such systems in the past.
Implementation of an Origami Dynamics Model Based on the Absolute Nodal Coordinate Formulation (ANCF)
Authors: Tao Jiayue , Li Suyi
Published: November 2022

Origami — the ancient art of paper folding — has been widely adopted as a design and fabrication framework for many engineering applications, including multi-functional structures, deployable spacecraft, and architected materials. These applications typically involve complex and dynamic deformations in the origami facets, necessitating high-fidelity models to better simulate folding-induced mechanics and dynamics. This paper presents the formulation and validation of such a new model based on the Absolute Nodal Coordinate Formulation (ANCF), which exploits the tessellated nature of origami and describes it as an assembly of flexible panels rotating around springy creases. To estimate the crease folding, we mathematically formulate a “torsional spring connector” in the framework of ANCF and apply it to the crease nodes, where the facets meshed by ANCF plate elements are interconnected. We simulate the dynamic folding of a Miura-ori unit cell and compare the results with commercial finite element software (ABAQUS) to validate the modeling accuracy. The ANCF model can converge using significantly fewer elements than ABAQUS without sacrificing accuracy. Therefore, this high-fidelity model can help deepen our knowledge of folding-induced mechanics and dynamics, broadening the appeals of origami in science and engineering.
Self-Assembly by 4D Printing: Design and Fabrication of Sequential Self-Folding
Authors: Zeng Siyuan , Gao Yicong , Tan Jianrong , Wei Zhe
Published: November 2022

Folding-based self-assembly is ubiquitous in nature with examples ranging from the formation of cellular components to winged insects. It has highly potential applications in packaging of solar cells and space structures. In this study, we present a sequential self-assembly design and fabrication approach that is realized by thermal activation of bilayer actuators and transforms two-dimensional nets into three-dimensional structures. The time-dependent behaviors and shape memory performances of each bilayer actuator via experimental methods are investigated. The relationship between structure design parameters of bilayer actuators and their correspondingly self-assembly speed has been studied. Our main findings the process parameters of 4D printing is a simple and effective design principle for controlling the speed of self-assembly. By properly designing the bilayer actuators, 3D printed structures with programmed bilayer actuators respond rapidly to a thermal stimulus, and self-fold to specified shapes in controlled shape changing sequences. A folding box structure is used as an example to illustrate the methodology, which normally requires a folding sequence in order to form a stable and fully packed structure. Measurements of the spatial and temporal nature of self-assembly structures are in good agreement with the desired configurations.
Numerical Computation of the Acoustic Response of an Active Airfoil With Impedance Boundary Conditions to a Turbulent Wake
Authors: Ezzine Mouhamed Mounibe , Rodriguez Jonathan , Perez Matthias , Billon Kevin , Mardjono Jacky , Clair Vincent , Collet Manuel
Published: November 2022

The noise generated by the interaction of the turbulent wake of the fan with the Outlet Guide Vanes (OGV) is a major component of turbofan engine noise. The development of noise reduction concepts applied to the OGV is an intensive research topic, with some current effort dedicated to an active solution making use of piezoelectric actuators integrated within the OGV airfoils to control the surface impedance. In order to define target values for the impedance that would lead to significant noise reduction over a chosen frequency range, a numerical method is being investigated in the present work. The method relies on solving the linearized Euler’s equations in the frequency domain around an airfoil and introducing a velocity fluctuation representing the fan’s turbulent wake upstream of the airfoil. An impedance boundary condition can be applied to the airfoil surface, and optimal values could be found through a parametric study. This paper presents the first set of 2D simulations that were performed to assess the capability of the method to show the effects of an impedance on the airfoil acoustic response, by comparison with a rigid one.
Numerical Investigation of Bistable Energy Harvesting Based on Silicone Dielectric Elastomer Generators
Authors: Moretti Giacomo , Rizzello Gianluca
Published: November 2022

This paper presents a concept of bistable dielectric elastomer generator (DEG) and investigates its performance via numerical simulations. Whereas resonant DEG designs are largely used to achieve large convertible energy density over specific frequency ranges, bistability represents a potential alternative approach, suitable to scavenge energy over broad low-frequency ranges. In contrast to resonant designs, which demand for large inertia and are thus hard to down-scale, bistability might be an enabling solution for low-frequency harvesting at small scales. In this work, we study a DEG made of silicone. We first develop an electro-mechanical model of the system, based on established approaches and experimentally validated material properties. We then use the model to compare the performance of a monostable resonant implementation of the system and a bistable one, proving that the bistable system can potentially provide significantly higher convertible energy densities in a broad range of excitation conditions.
Investigation of Mounting Techniques for Concrete Floor-Mounted Accelerometers Used in Smart Buildings
Authors: Hott Jacob W. , Anton Steven R.
Published: November 2022

In smart building infrastructure, the mounting of dynamic measurement devices must be carefully determined to obtain meaningful data and accurately record the dynamics within a building. Specifically, it is important to develop a sensor mounting method so that the highest frequency band of interest can be accurately obtained. This is especially crucial in safety applications such as footstep localization, fall detection, and gunshot detection since high frequencies could possess useful information.

Currently, it is common practice in structural health monitoring of building infrastructure for sensors to be mounted either temporarily on the surface of a floor with wax or permanently on the underside of the structural steel floor joists. Using either of these methods causes limitations in either the permanence of the setup or in the placement of sensors. This paper explores several typical mounting locations and a novel accelerometer mounting method designed to overcome these limitations by mounting accelerometers on the underside of a concrete floor structure’s corrugated steel floor tray. The novel mounting method consists of a mounting plate fastened to a concrete floor with concrete anchors and a tapped hole for accelerometer mounting. This method will be evaluated through experimental testing and analysis on two developed floor section mockups mimicking the floor structure in Tennessee Technological University’s newly constructed Lab Science Commons building and the floor currently being constructed in the new Ashraf Islam Engineering Building. Testing is carried out by impacting the floor section in 11 locations with a modal hammer while measuring the response of accelerometers mounted at various locations. The frequency response of the concrete anchored accelerometers is assessed in two scenarios so results can be compared to results for beam mounted accelerometers.

From testing, it is found that signals obtained from the bottom center and bottom flange beam mounting locations are attenuated within specific frequency bands. The bottom center beam mounting location experiences signal attenuation in the frequency range of 500 to 1500 Hz. Meanwhile, the bottom flange beam location experiences attenuation from 2800 to 3200 Hz, the topmost evaluated frequency. Mounting positions on the I-beam’s upper flange and the bottom of the concrete floor section, both with and without the beam present, do not display signal attenuation characteristics. Furthermore, a significant amount of system dynamics is seen in signals obtained for mounting locations residing on the I-beam compared to those mounted on the floor section. This increase is suspected to be a result from both the dynamics of the beam itself and the boundary conditions between the beam and floor section. These characteristics are also seen in mounting locations on the concrete floor section with an I-beam present but are not seen with the same intensity as mounting locations existing directly on the I-beam.
Challenges of Upscaling Power Composites for Aerospace Applications
Authors: Geier Sebastian , Petersen Jan , Wierach Peter
Published: November 2022

Increasing electrification in the aerospace sector as well as the challenge of powering an entire aircraft electrically places demands for the supply and storage of electrical energy. Energy devices must therefore be powerful and lightweight at the same time for efficient performance of the overall transportation system. One possibility to improve the performance by reducing weight and volume is the combination of structural and energy storing functions. Due to its lay-up, a composite is particularly suitable for this challenge. Of course, batteries are one of the most important components, but when it comes to being integrated in composite structures, their potential is reduced drastically because of their limited lifetime. In contrast, supercapacitors are a very promising technology. Their system features several advantages such as power density and cycle stability. Due to their cycle stability, supercapacitors are the ideal energy device for integration into areas that are difficult to access, such as the lay-up of composite structures. This publication deals with the strategy of structure-compliant integration of pouch supercapacitor cells. The aim is to operate different peak power applications needed for space missions. The material combination has to be optimized to achieve the best possible electromechanical performance. During the development, sets of structural supercapacitors with different scales are built to check their specific capacity. Often the specific properties drop by scaling up, but during this development the specific capacity of 0.24F/cm2 was even kept for the full-size demonstrator. Furthermore, this approach allows the reduction of volume and weight by 70–80% compared to a structure using commercial supercapacitors.
Analogies Between Stimuli-Responsive (Smart) Hydrogel-Based Microfluidic Valves and Electronic Transistors
Authors: Marschner Uwe , Beck Anthony , Mehner Philipp , Paschew Georgi , Voigt Andreas , Richter Andreas
Published: November 2022

Stimuli-sensitive or responsive (smart) hydrogels, or chemofluidic transistors, are the base of the key control elements of smart chemomechanical valves. These valves have an outstanding potential for miniaturized, integrated sensor and actuator systems in many application areas and especially for lab-on-chip technology. Due to the multifaceted design parameters the design and realization of hydrogel-based systems are exceptionally complex and demanding.

In this work we compare two types of stimuli-sensitive hydrogel-based valves with two types of electronic transistors and analyze analogies. As a result, the membrane isolated chemical volume phase transition Transistors (MIS-CVPT’s) exhibit a behavior with various analogies to electrical Field Effect Transistors (FET’s). The FET device embodies a voltage-controlled channel resistor, which is related to the chemically controlled fluidic channel of the MIS-CVPT. Chemical volume phase transition transistors (CVPT’s) on the other hand show in part similarities both to the bipolar transistor (BJT) and the MOSFET. The analogies allow a closed description of a microfluidic system by equivalent circuits and an efficient behavioral simulation by sophisticated circuit simulators.

Several chemofluidic circuits, as a microfluidic oscillator, a NAND gate and an Analog/Digital Converter (ADC) and their behavioral simulation will be presented. The applied lab-on-a-chip (LoC) predictive simulation-based design concept is very helpful as it saves many practical experiments and leads to optimized components.
Hinged Tile-Based Air Surface for Morphing Windshield Cowling
Authors: Li Tiantian , Luntz Jonathan , Brei Diann , Kim Wonhee , Alexander Paul
Published: November 2022

The gap between the windshield and hood provides an opening for windshield wipers to operate, but can be problematic at other times, gathering leaves and snow. Active morphing approaches provide an opportunity to create a windshield cowling that addresses this issue by covering the gap normally, and actively curling out of the way to allow wiper operation. Most existing morphing techniques lack the simultaneous force/stroke generation, cannot perform two-way actuation, or fail to rigidly hold their position against varying loads such as wind. This paper introduces a useful curling air surface based on hinged T-shaped tiles that improves upon existing morphing technologies by adding straightening actuation to out-of-plane curling with large force and deflection, while also providing rigid position holding. An upper curling bladder encloses the hinged T-shaped tiles and pulls the T-protrusions together when vacuumed, causing the surface to curl. Lower straightening bladders span the hinge lines and pull the tiles flat when inflated. Through vacuum and inflation of the two bladders, the air surface covers and uncovers the gap against the wind load, and can hold its curled position rigidly using inter-tile hard stops. To predict the air surface performance, an air surface model is aggregated from multiple instances of a unit curling model that is derived from first principles with additional phenomenological terms. The validated model enables a scalable dimensionless design space visualization for general curling applications against loads, which is applied to design a windshield cowling. The resulting design is tested with its wind retention ability and built into a full-scale prototype windshield cowling operating on a sedan. This paper provides the technology concept and supporting model and design approach to more broadly apply this useful air surface architecture to applications in automotive (air dam, adaptive seating), aerospace (morphing wing), architecture (self-assembly shelters) and other domains.
Experimental Tests of a SMA Based Blade Twist System: Wind Tunnel and Whirl Tower Outcomes
Authors: Ameduri Salvatore , Ciminello Monica , Concilio Antonio , Dimino Ignazio , Galasso Bernardino , Guida Mariano , Miceli Marco F. , Riemenschneider Johannes , Kalow Steffen , Luebker Jannis , Fournier Stephane , Rivero Andres E. , Woods Benjamin K. S.
Published: November 2022

In this work, attention is paid on two specific moments foreseen in the European Project “Shape Adaptive Blades for Rotorcraft Efficiency”: the test validation in wind tunnel and whirl tower representative environments of a morphing architecture aiming at altering the twist law of an helicopter blade.

The architecture, based on Shape Memory Alloy technology, was tested in the abovementioned environments to get enough information on its functionality under representative loads and on its capability of producing significant variations of the original performance.

The wind tunnel tests held at the University of Bristol, captured the effect of the progressive span wise twist activation, highlighting the capability of improving the aerodynamic efficiency.

The whirl tower test campaign organized at the DLR plant, demonstrated the capability of the system of altering its original twist, even in presence of centrifuge forces tending to stretch the blade and, thus, to make it stiffener. In addition, twist related effects were measured, as the produced flapping motion.

The achieved results proved, in relevant environment, the effectiveness of the architecture both from a functional (additional twist production) and an effectiveness (alteration of the aerodynamics) point of view. The experimental outcomes paved the way to a critical overview aiming at identifying potential issues and relevant approaches for further increase of the technology readiness level of the concept.
Mechatronic Design and Physical Prototyping of a Three-Fingered Gripper for Underwater Manipulation
Authors: Baggetta Mario , Berselli Giovanni , Palli Gianluca , Melchiorri Claudio
Published: November 2022

Researchers involved in the development of dexterous robotic hands agree that a mechatronics approach to hand design is the only way to generate new levels of functional capabilities. As reported by several authors, the problems relative to the single component or subsystem design must be solved within a general frame of compatibility and integrability. In this paper the virtual and physical prototyping of a three-fingered gripper designed to be mounted on an autonomous underwater vehicle (AUV) for underwater manipulation as well as sampling specimens is reported. In particular, an overall description of the gripper design is discussed, with special attention to the required actuation and tendon transmission system, its integration within the mechanical structure and the required control architecture. Different solutions for the joint configuration and the structure of the tendon network adopted for the transmission system are presented. The integrated design of the finger is reported and the motivations leading to this particular implementation are thoroughly addressed, taking into account both the mechanical constraints and the control requirements. The overall finger design is modular, so that other design solutions comprising multiple fingers (e.g. for in-hand manipulation purposes or realization of cage gripper) are easily achievable by adding further modules without increase the overall dimensions of the device. Virtual prototype results are finally provided and discussed to prove the gripper behaviour and capabilities.