bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibition of lytic polysaccharide monooxygenase by natural plant extracts
Authors: Tokin Radina , Frandsen Kristian E. H. , Ipsen Johan Ørskov , Lo Leggio Leila , Poojary Mahesha M. , Berrin Jean‐Guy , Grisel Sacha , Brander Søren , Jensen Poul Erik , Johansen Katja Salomon
Published: August 2021

Lytic polysaccharide monooxygenases (LPMOs) are monocopper enzymes of industrial and biological importance. In particular, LPMOs play important roles in fungal lifestyle. No inhibitors of LPMOs have yet been reported.

In this study, a diverse library of 100 plant extracts was screened for LPMO activity‐modulating effects. By employing protein crystallography and LC–MS, we successfully identified a natural LPMO inhibitor.

Extract screening revealed a significant LPMO inhibition by methanolic extract of Cinnamomum cassia (cinnamon), which inhibited LsAA9A LPMO from Lentinus similis in a concentration‐dependent manner. With a notable exception, other microbial LPMOs from families AA9 and AA10 were also inhibited by this cinnamon extract. The polyphenol cinnamtannin B1 was identified as the inhibitory component by crystallography. Cinnamtannin B1 was bound to the surface of LsAA9A at two distinct binding sites: one close to the active site and another at a pocket on the opposite side of the protein. Independent characterization of cinnamon extract by LC–MS and subsequent activity measurements confirmed that the compound inhibiting LsAA9A was cinnamtannin B1.

The results of this study show that specific natural LPMO inhibitors of plant origin exist in nature, providing the opportunity for future exploitation of such compounds within various biotechnological contexts.
Subjective measurement of the Stiles‐Crawford effect of the first kind with variation in accommodation
Authors: Nilagiri Vinay Kumar , Suheimat Marwan , Lambert Andrew J , Atchison David A
Published: August 2021

Purpose

To measure the Stiles‐Crawford effect of the first kind (SCE‐I), corresponding to central vision, with innovative technology to evaluate changes in the directionality and photoreceptor alignment with accommodation.

Methods

A uniaxial Maxwellian system (spot size in pupil 0.5 mm diameter) was employed, incorporating a spatial light modulator to flicker at 2 Hz between two 2.3° fields corresponding to test (peripheral pupil) and reference (pupil centre) positions. Participants determined thresholds at 13 positions along the horizontal pupil meridian by indicating if the test field was brighter or dimmer than the reference field. Thresholds were determined by a staircase procedure after four reversals at each pupil location. After pupil dilation, seven emmetropes were tested at 0 D to 6 D accommodation stimulus levels in 2 D intervals. Data were fit by the Gaussian function, both when the fits were unforced or forced to pass through the sensitivity expected for the reference point. Directionality (ρ) and peak location values were determined for unforced and forced fits.

Results

Regression slopes for ρ as a function of accommodation stimulus were not significant. There was a tendency for to shift temporally with increasing accommodation across the 6 D stimulus range. This was not significant for regression fitting (–0.059 mm/D, R2 = 0.06, p = 0.20), but a paired t‐test for 0 and 6 D stimuli showed a weakly significant change of 0.62 mm (p = 0.05). The differences between the two fitting approaches were small and non‐significant.

Conclusions

Directionality did not change with accommodation, but the pupil peak location showed a significant temporal shift of approximately 0.62 mm with 6 D accommodation stimulus. It is possible that substantial changes in the directionality and a shift in the direction of peak location might occur at very high levels of accommodation.
Drosophila yellow‐h encodes dopaminechrome tautomerase: A new enzyme in the eumelanin biosynthetic pathway
Authors: Barek Hanine , Zhao Heya , Heath Katerina , Veraksa Alexey , Sugumaran Manickam
Published: August 2021

Melanin is a widely distributed phenolic pigment that is biosynthesized from tyrosine and its hydroxylated product, dopa, in all animals. However, recent studies reveal a significant deviation from this paradigm, as insects appear to use dopamine rather than dopa as the major precursor of melanin. This observation calls for a reconsideration of the insect melanogenic pathway. While phenoloxidases and laccases can oxidize dopamine for dopaminechrome production, the fate of dopaminechrome remains undetermined. Dopachrome decarboxylase/tautomerase, encoded by yellow‐f/f2 of Drosophila melanogaster, can convert dopaminechrome into 5,6‐dihydroxyindole, but the same enzyme from other organisms does not act on dopaminechrome, suggesting the existence of a specific dopaminechrome tautomerase (DPT). We now report the identification of this novel enzyme that biosynthesizes 5,6‐dihydroxyindole from dopaminechrome in Drosophila. Dopaminechrome tautomerase acted on both dopaminechrome and N‐methyl dopaminechrome but not on dopachrome or other aminochromes tested. Our biochemical and molecular studies reveal that this enzyme is encoded by the yellow‐h gene, a member of the yellow gene family, and advance our understanding of the physiological functions of this gene family. Identification and characterization of DPT clarifies the precursor for melanin biosynthetic pathways and proves the existence of an independent melanogenic pathway in insects that utilizes dopamine as the primary precursor.
Global impact of physical inactivity and implications for public health nursing
Authors: Moxley Elizabeth , Webber‐Ritchey Kashica J. , Hayman Laura L.
Published: August 2021

Physicalinactivity has been a public health problem worldwide for more than a decade. Of those who are physically active, a substantial percentage engage solely in low or very low physical activity (PA) levels. In the last 3 decades, the prevalence of PA in the United States has decreased with approximately 80% of adults not meeting the recommended guidelines for aerobic and muscle strengthening PA. The PA levels of youth have dramatically decreased with 85% of adolescents reporting no PA. Regular PA participation can aid in preventing chronic diseases. A strong inverse dose‐response relationship exists between PA and the incidence of cardiovascular disease, all‐cause and cardiovascular mortality. Moreover, low cardiorespiratory fitness levels are a risk factor for cardiovascular diseases: the leading cause of death and disability globally. Conversely, high amounts of moderate‐to‐vigorous intensity PA at levels 3–5 times recommended in guidelines reduce risk for all cause mortality. Socio‐ecological determinants of PA are essential considerations for promoting across the life course. In health care and community settings, public health nurses have opportunities to promote PA through a socio‐ecological approach across the life course of individuals and diverse populations.
Primary care nurses’ challenges, opportunities, and facilitators of elder abuse intervention in Malaysia
Authors: Mohd Mydin Fadzilah Hanum , Othman Sajaratulnisah , Choo Wan Yuen , Mohd Hairi Noran Naqiah , Mohd Hairi Farizah , Ali Zainudin , Abdul Aziz Suriyati
Published: August 2021

Objectives

To explore the views of nurses on challenges, perceived roles and improvement strategies concerning elder abuse intervention in Malaysia.

Design and sample

Eleven focus group discussions were conducted using a semi‐structured interview based on the socio‐ecological framework. The data were analyzed using a multistep process of thematic analysis.

Results

Three themes emerged from the data analysis: (1) The predicament: being unwilling or not able to intervene (2) Bridging the older people and health system gap (3) Getting to grips with the barriers. There are multifactorial contributors identified at the individual, interpersonal, organizational, community and policy levels in each theme. These factors interact across the levels to influence nurses’ capability to intervene in elder abuse.

Conclusion

A framework is needed to articulate Malaysian nurses’ role in elder abuse intervention in terms of personal and professional development through culturally sensitive education and the establishment of clinical guidelines in the primary care setting. Strengthening organizational support and the institution of national policy and permissive reporting laws of elder abuse will empower the primary care nurses to address elder abuse in primary care settings and communities.
“It Was Actually Pretty Easy”: COVID‐19 Compliance Cost Reductions in the WIC Program
Authors: Barnes Carolyn , Petry Sarah
Published: August 2021

In recent years, scholars have examined the barriers to accessing public assistance benefits. Research identifies learning, compliance, and psychological costs as deterring program use. Compliance costs reflect the burdens of following program rules, which may entail providing documentation, responding to discretionary demands of bureaucrats, or attending appointments to maintain benefits. Studies identify one element of compliance costs—quarterly appointments—as a barrier to continued WIC participation. This article draws on 44 in‐depth qualitative interviews with participants in the Special Supplemental Nutrition Assistance Program for Women, Infants, and Children (WIC). We examine how WIC participants perceive the reduction of compliance costs following the implementation of remote appointments in response to the COVID‐19 pandemic. WIC participants report satisfaction with remote appointments and a reduction in the compliance costs of accessing and maintaining benefits. We conclude by recommending longer term changes to policy and practices to increase access and continuity in WIC receipt.
Contribution of the mutation T865G in TPH1 gene to the genetic potentiality of housed Mongolian sheep to year‐round breeding
Authors: Liu Chenhui , Jiang Xunping , Chi Shaxuan , Bo Dongdong , Liu Guiqiong
Published: August 2021

Seasonal breeding is widespread in sheep and significantly affects the development of the housed sheep industry. To improve and balance the reproduction performance of sheep, year‐round breeding has the goal of modern sheep farming. The tryptophan hydroxylase (TPH), which initiates and regulates biosynthesis of melatonin, is an important player in the formation of mammalian year‐round breeding. However, little is known about its role in regulation of sheep seasonal breeding. In this study, a missense mutation, T865G in TPH1 gene was detected in 328 individuals of six Mongolian sheep groups. It was positively selected among Mongolian sheep. This mutation may appear between 13,683 and 350,973 years ago and only exist in Hu sheep now. In Hu sheep, the frequency of allele T was 89.66%, and that of allele G was 10.34%. The TPH1 protein structure and property analysis suggested that this mutation from T to G affect the three‐dimensional structure and reduce the hydropathicity of catalytic core. When the allele is T, the protein activity is twice that of the allele G, and their difference was significant (p < .05). In conclusion, T865G is an ancient mutation of TPH1 gene and affects the function of TPH protein, which may contribute to the genetic potentiality of Mongolian sheep to year‐round breeding.
Phosphorus puts a mortgage on restoration of species‐rich grasslands on former agricultural land
Authors: Goossens Elias P. , De Schrijver An , Schelfhout Stephanie , Vanhellemont Margot , Verheyen Kris , Mertens Jan
Published: August 2021

Large‐scale biodiversity loss is one of the most urgent global issues. The Convention on Biological Diversity created a vision to ecologically restore ecosystems by 2050. The European Union follows this ambition, and member states are required to select Special Areas of Conservation (SACs) to develop and restore; one example is species‐rich semi‐natural grassland. Species‐rich grassland restoration requires time for restoring both abiotic conditions, e.g. low soil phosphorus concentrations, and biotic conditions, e.g. introduction of missing species. For 507 grasslands (in northern Belgium) situated in SACs, we calculated the time needed for restoring necessary phosphorus‐poor conditions. Only 11% of the grasslands already met the strictest phosphorus‐target. We found that less than a fourth of the other 452 grasslands will reach this phosphorus‐target by 2050 through mowing. P‐mining, a more intensive technique involving fertilization of nitrogen and potassium, could help achieve this phosphorus‐target on about slightly more than a third of these grasslands by 2050. The soil iron concentration strongly affected the restoration times. A total of 65% of the grasslands will require alternatives like topsoil removal or selection of a different, less ambitious grassland target. These calculations do not include the time needed for biotic restoration. Because grassland restoration is a long‐term process, we advocate better protection of still existing species‐rich grasslands. Restoration is a last resort in safe‐guarding biodiversity.
Saltwater and nutrient legacies reduce net ecosystem carbon storage despite freshwater restoration: insights from experimental wetlands
Authors: Lee Dong Yoon , Kominoski John S. , Kline Michael , Robinson Michelle , Roebling Suzy
Published: August 2021

Net ecosystem carbon balance is a comprehensive assessment of ecosystem function that can test restoration effectiveness. Coastal peatlands are globally important carbon sinks that are vulnerable to carbon loss with saltwater intrusion. It is uncertain how wetland carbon stocks and fluxes change during freshwater restoration following exposure to saltwater and elevated nutrients. We restored freshwater to sawgrass (Cladium jamaicense) peat monoliths from freshwater marshes of the Everglades (Florida, U.S.A.) that had previously been exposed to elevated salinity (approximately9 ppt) and phosphorus (P) loading (1 g P m−2 year−1) in wetland mesocosms. We quantified changes in water and soil physicochemistry, plant and soil carbon and nutrient standing stocks, and net ecosystem productivity during restoration. Added freshwater immediately reduced porewater salinity from >8 to approximately 2 ppt, but elevated porewater dissolved organic carbon persisted. Above‐ and belowground biomass, leaf P concentrations, and instantaneous rates of gross ecosystem productivity (GEP) and ecosystem respiration (ER) remained elevated from prior added P. Modeled monthly GEP and ER were higher in marshes with saltwater and P legacies, resulting in negative net ecosystem productivities that were up to 12× lower than controls. Leaf litter breakdown rates and litter P concentrations were 2× higher in marshes with legacies of added saltwater and P. Legacies of saltwater and P on carbon loss persisted despite freshwater restoration, but recovery was greatest for freshwater marshes exposed to saltwater alone. Our results suggest that restoration in nutrient‐limited freshwater wetlands exposed to saltwater intrusion and nutrient enrichment is a slow process.
Ventilatory support at home for children: A joint position paper from the Thoracic Society of Australia and New Zealand/Australasian Sleep Association
Authors: Chawla Jasneek , Edwards Elizabeth A. , Griffiths Amanda L. , Nixon Gillian M. , Suresh Sadasivam , Twiss Jacob , Vandeleur Moya , Waters Karen A. , Wilson Andrew C. , Wilson Susan , Tai Andrew
Published: August 2021

The goal of this position paper on ventilatory support at home for children is to provide expert consensus from Australia and New Zealand on optimal care for children requiring ventilatory support at home, both non‐invasive and invasive. It was compiled by members of the Thoracic Society of Australia and New Zealand (TSANZ) and the Australasian Sleep Association (ASA). This document provides recommendations to support the development of improved services for Australian and New Zealand children who require long‐term ventilatory support. Issues relevant to providers of equipment and areas of research need are highlighted.
Comparing Environmental Risk Regulations in China and the United States
Authors: Li Huanhong , Xu Jianhua , Wiener Jonathan B.
Published: August 2021

The relative stringency of risk regulation across countries may have significant implications for public health and environmental outcomes, as well as for economic and trade impacts. In this study, we build on prior literature—which has often employed qualitative case studies, and has often focused on comparing the United States and Europe—by using a quantitative evidential reasoning approach to compare the relative stringency of federal/central level written rules for 45 randomly selected environmental risks in the United States and China. We find that, on average, in this sample of 45 environmental risks, the written rules for environmental risk regulation were more stringent in the United States than in China. Within this sample, we find that relative stringency was selective, leaning in both directions, as the United States and China each regulated some risks more stringently than the other; for example, the US written rules were more stringent for risks of toxic chemicals and most air pollutants, whereas China's written rules were more stringent for risks in agriculture. We also observe nuanced differences in relative regulatory stringency within sectors and risks; even where one country regulated one risk more stringently, the other country may regulate certain aspects of that risk more stringently. We comment on possible explanations for the patterns we observe. Our methods and findings may contribute to better understanding of comparative risk regulation across the United States and China, and worldwide. We also recognize that in addition to the written rules studied here, countries may also vary in their implementation.
The 1918 epidemic and a V‐shaped recession: evidence from historical tax records*
Authors: Dahl Christian Møller , Hansen Casper Worm , Jensen Peter Sandholt
Published: August 2021

We exploit high‐quality vital statistics data and annual income data, obtained from historical municipality tax records, to study the economic aftermath of the 1918 influenza epidemic in Denmark. We find that average income followed a V‐shaped path from 1917 to 1919, and (if anything) municipalities with higher mortality rates because of the 1918 influenza epidemic experienced more pronounced declines and recoveries. In addition, national month‐by‐industry unemployment data show that unemployment rates were high during the epidemic, but decreased again a couple of months after the epidemic receded. Evidence from the Danish stock‐market exchange also indicates that the epidemic only had short‐lived effects on the economy.
Survey of cytokines on ocular surfaces of atopic dogs by multiplex analysis using two sampling methods – a pilot study
Authors: Pressanti Charline , Ravailhe Elodie , Castellote‐Brun Jessie , Amalric Nicolas , Lecru Line‐Alice , Kondratjeva Jevgenija , Moog Fabien , Combarros Daniel , Douet Jean‐Yves , Cadiergues Marie Christine
Published: August 2021

Background

Conjunctivitis in atopic dogs has already been described yet is rarely observed, and likely underdiagnosed in practice.

Objectives

To assay various cytokines in tears and conjunctivae from atopic and normal dogs, and to compare canine atopic dermatitis‐associated conjunctivitis with controls.

Animals

Ten atopic and ten normal client‐owned dogs.

Methods and materials

Ocular surfaces were sampled bilaterally in a prospective study, using two different methods. Tear samples were obtained with a sterile swab previously moistened with saline solution (method A). Conjunctival impressions were obtained with a conjunctival impression device (method B). For each sample, the concentrations of a panel of 13 cytokines were measured by multiplex analyses. CADESI‐4, pruritus (PS) and conjunctival (CS) scores were determined.

Results

Among the measured cytokines, only granulocyte‐macrophage colony‐stimulating factor (GM‐CSF), keratinocyte‐derived chemokine (KC)‐like and interleukin (IL)‐8 were above the limit of quantification in most samples. Absolute amounts of each cytokine were always higher in samples obtained with method A than with method B. GM‐CSF amounts were lower in atopic dogs (method A, P=0.02; method B, P=0.0005). KC levels were higher in atopic dogs, yet the differences were not significant. IL‐8 amounts were higher in atopic dogs (method A, P=0.0003; method B, P=0.006).

Conclusions and clinical relevance

Regardless of the method, these preliminary results suggest an overexpression of IL‐8 in conjunctivae and tears of atopic dogs despite subtle conjunctival symptoms. As IL‐8 is commonly found in many inflammatory conditions, further studies are needed to determine its specificity in atopic conjunctivitis.
Hypertrophied human adipocyte spheroids as in vitro model of weight gain and adipose tissue dysfunction
Authors: Ioannidou Anna , Alatar Shemim , Schipper Ruby , Baganha Fabiana , Åhlander Matilda , Hornell Amanda , Fisher Rachel M. , Hagberg Carolina E
Published: August 2021

Key points

Adipocyte enlargement is a key feature of obesity and associated with insulin resistance and metabolic disease

The cause and consequences of adipocyte enlargement have remained hard to study in vitro due to a lack of human cell models with representative morphology

This paper provides an easily set up spheroid culture method, HUVAS (human unilocular vascularized adipocyte spheroids), for the differentiation and culturing of human adipocytes with a more unilocular morphology

We show that providing adipocyte progenitors with a vascular differentiation niche is key for achieving in vitro differentiated adipocytes with large lipid droplets

Lipid treatment of the HUVAS spheroids can further adipocyte enlargement and induce cellular dysfunction, mimicking the in vivo effects of weight gain

The model will allow a wider research community to perform mechanistic studies of the factors impacting on human adipocyte differentiation and growth, increasing our understanding of how obesity develops and why it has such detrimental consequences on whole body metabolism

The rise in obesity prevalence has created an urgent need for new and improved methods to study human adipocytes and the pathogenic effects of weight gain in vitro. Despite the proven advantage of culturing adipocyte progenitors as 3D structures, the majority of studies continue to use traditional 2D cultures which result in small, multilocular adipocytes with poor representability. We hypothesized that providing differentiating pre‐adipocytes with a vascular growth niche would mimic in vivo adipogenesis and improve the differentiation into unilocular adipocytes. Here we present HUVAS (human unilocular vascularized adipocyte spheroids), a simple, easily applicable culture protocol that allows for the differentiation of human adipocytes with a more unilocular morphology and larger lipid droplets than previous protocols. Moreover, we offer a protocol for inducing adipocyte enlargement in vitro, resulting in larger lipid droplets and development of several key features of adipocyte dysfunction, including altered adipokine secretion, impaired lipolysis and insulin resistance. Taken together, our HUVAS model offers an improved culture system for studying the cellular and molecular mechanisms causing metabolic dysfunction and inflammation in human adipose tissue during weight gain.
Sexual dimorphism in liver cell cycle and senescence signalling pathways in young and old rats
Authors: Lomas‐Soria Consuelo , Cox Laura A. , Nathanielsz Peter W. , Zambrano Elena
Published: August 2021

At the molecular level, cellular ageing involves changes in multiple gene pathways. Cellular senescence is both an important initiator and a consequence of natural ageing. Senescence results in changes in multiple cellular mechanisms that result in a natural decrease in cell cycle activity. Liver senescence changes impair hepatic function. Given the well‐established sexual dimorphism in ageing, we hypothesized that the natural hepatic ageing process is driven by sex‐dependent gene mechanisms. We studied our well‐characterized normal, chow‐fed rat ageing model, lifespan ∼850 days, in which we have reported ageing of metabolism, reproduction and endocrine function. We performed liver RNA‐seq on males and females at 110 and 650 days to determine changes in the cell cycle and cellular senescence signalling pathways. We found that natural liver ageing shows sexual dimorphism in these pathways. RNA‐seq revealed more male (3967) than female (283) differentially expressed genes between 110 and 650 days. Cell cycle pathway signalling changes in males showed decreased protein and expression of key genes (Cdk2, Cdk4, Cycd and PCNA) and increased expression ofp57 at 650 vs 110 days. In females, protein and gene expression of cell growth regulators, e.g. p15 and p21, which inhibit cell cycle G1 progression, were increased. The cell senescence pathway also showed sexual dimorphism. Igfbp3, mTOR and p62 gene and protein expression decreased in males while those ofTgfb3 increased in females. Understanding the involvement of cell cycling and cellular senescence pathways in natural ageing will advance evaluation of mechanisms associated with altered ageing and frailty trajectories.

image

Key points

In rats RNA‐seq analysis showed sexual dimorphism in gene expression across the life‐course between 110 and 650 days of life.

Fourteen times more liver transcriptome and six times more pathway changes were observed in males compared with females.

Significant changes were observed in several signalling pathways during ageing. Bioinformatic analysis were focused on changes in genes and protein products related to cell cycle and cellular senescence pathways.

Males showed decreased protein product and expression of the key genes Cdk2 and Cdk4 responsible for cell cycle progression while females increased protein product and expression of p21 and p15, key genes responsible for cell cycle arrest.

In conclusion, normative rat hepatic ageing involves changes in cellular pathways that control cell cycle arrest but through changes in different genes in males and females. These findings identify mechanisms that underlie the well‐established sexual dimorphism in ageing.
Detection of Machinery Failure Signs From Big Time-Series Data Obtained by Flow Simulation of Intermediate-Pressure Steam Turbines
Authors: Komatsu Kazuhiko , Miyazawa Hironori , Yiran Cheng , Sato Masayuki , Furusawa Takashi , Yamamoto Satoru , Kobayashi Hiroaki
Published: August 2021

The periodic maintenance, repair, and overhaul (MRO) of turbine blades in thermal power plants are essential to maintain a stable power supply. During MRO, older and less-efficient power plants are put into operation, which results in wastage of additional fuels. Such a situation forces thermal power plants to work under off-design conditions. Moreover, such an operation accelerates blade deterioration, which may lead to sudden failure. Therefore, a method for avoiding unexpected failures needs to be developed. To detect the signs of machinery failures, the analysis of time-series data is required. However, data for various blade conditions must be collected from actual operating steam turbines. Further, obtaining abnormal or failure data is difficult. Thus, this paper proposes a classification approach to analyze big time-series data alternatively collected from numerical results. The time-series data from various normal and abnormal cases of actual intermediate-pressure steam-turbine operation were obtained through numerical simulation. Thereafter, useful features were extracted and classified using K-means clustering to judge whether the turbine is operating normally or abnormally. The experimental results indicate that the status of the blade can be appropriately classified. By checking data from real turbine blades using our classification results, the status of these blades can be estimated. Thus, this approach can help decide on the appropriate timing for MRO.
Reducing Uncertainty in the Onset of Combustion Instabilities Using Dynamic Pressure Information and Bayesian Neural Networks
Authors: McCartney Michael , Sengupta Ushnish , Juniper Matthew
Published: August 2021

Modern low-emission combustion systems with improved fuel-air mixing are more prone to combustion instabilities and, therefore, use advanced control methods to balance minimum NOx emissions and the presence of thermoacoustic combustion instabilities. The exact operating conditions at which the system encounters an instability are uncertain because of sources of stochasticity, such as turbulent combustion, and the influence of hidden variables, such as unmeasured wall temperatures or differences in machine geometry within manufacturing tolerances. Practical systems tend to be more elaborate than laboratory systems and tend to have less instrumentation, meaning that they suffer more from uncertainty induced by hidden variables. In many commercial systems, the only direct measurement of the combustor comes from a dynamic pressure sensor. In this study, we train a Bayesain Neural Network to predict the probability of onset of thermoacoustic instability at various times in the future, using only dynamic pressure measurements and the current operating condition. We show that on a practical system, the error in the onset time predicted by the Bayesain Neural Networks is 45% lower than the error when using the operating condition alone and more informative than the warning provided by commonly used precursor detection methods. This is demonstrated on two systems: (i) a premixed hydrogen/methane annular combustor, where the hidden variables are wall temperatures that depend on the rate of change of operating condition, and (ii) full-scale prototype combustion system, where the hidden variables arise from differences between the systems.
Numerical Study of Boiling Heat Transfer Around Horizontal and Inclined Cylinders
Authors: Saha Avik , Das Arup Kumar
Published: August 2021

Pool boiling around a heated cylinder having a diameter larger than the departure diameter of bubbles has been simulated numerically. Thermally uniform heat flux condition has been maintained at the outer surface of the cylinder, submerged at saturated water at atmospheric pressure. Using the volume of fluid type framework of liquid phase fraction in the domain, bubble life cycle around the horizontal cylinder has been analyzed to understand different stages of growth, sliding, merging prior to departure. An effort has also been made to characterize the bubble population, emerging from different sites over the cylindrical surface. The influence of cylinder inclination along its axis on these interfacial features has also been discussed using representative numerical simulation. Temperature profiles of the cylinder surface have been portrayed for both horizontal and inclined situations before presenting respective heat transfer coefficients.
Analytical Investigation of Non-Fourier Bioheat Transfer in the Axisymmetric Living Tissue Exposed to Pulsed Laser Heating Using Finite Integral Transform Technique
Authors: Kishore Pankaj , Kumar Sumit
Published: August 2021

This article proposes the closed-form solution of the generalized non-Fourier model-based bioheat transfer equation (BHTE) in Cylindrical coordinates to understand the thermal behavior of living tissue heated by a pulsed laser. The axisymmetric living tissue exposed to the non-Gaussian temporal profile of laser heating has been considered to investigate the non-Fourier bioheat transfer phenomena. The closed-form solution of the generalized non-Fourier model-based BHTE with time-dependent thermal energy generation has been obtained through the finite integral transform (FIT) technique. The analytical solution was juxtaposed to the corresponding numerical solution in order to determine its reliability. The numerical solution of the aforementioned governing equation has been obtained by the finite volume method (FVM). The results of both analytical and numerical solutions have been verified using results given in published literature. Subsequently, the dual-phase-lag (DPL) model's findings were juxtaposed to those obtained using the hyperbolic and traditional Fourier models. The effect of different parameters like relaxation times corresponding to the temperature gradient and heat flux, metabolic energy generation, and blood perfusion on the resultant temperature distribution inside the axisymmetric living tissue exposed to pulsed laser heating has been discussed. The importance of this study might be found in various applications such as laser-based-photothermal therapy, melting of the surface of metal and alloys by laser heating.
Scalable Thermal Simulation of Powder Bed Fusion
Authors: Zhang Yaqi , Shapiro Vadim , Witherell Paul
Published: August 2021

Powder bed fusion (PBF) has become a widely used additive manufacturing (AM) technology to produce metallic parts. In PBF, thermal field evolution during the manufacturing process plays an important role in determining both geometric and mechanical properties of the fabricated parts. Thermal simulation of the PBF process is computationally challenging due to the geometric complexity of the manufacturing process and the inherent computational complexity that requires a numerical solution at every time increment of the process. We propose a new thermal simulation of the PBF process based on the laser scan path. Our approach is unique in that it simulates the thermal history of the process on the discretization of the geometry implied by the process plan (i.e., scan path), as opposed to voxelization or meshing of the design geometry. The discretization is based on the laser scan path, and the thermal model is formulated directly in terms of the manufacturing primitives. An element growth mechanism is introduced to simulate the evolution of the melt pool during the manufacturing process. A spatial data structure, called contact graph, is used to represent the discretized domain and capture all thermal interactions during the simulation. The simulation is localized through exploiting spatial and temporal locality. This limits the need to update to at most a constant number of elements at each time-step, which implies that the proposed simulation not only scales to handle three-dimensional (3D) printed components of arbitrary complexity but also can achieve real-time performance. The simulation is fully implemented and validated against experimental data and other simulation results.
Proposal of a Machining Test to Evaluate Dynamic Synchronization Error of Rotary and Linear Axes With Reversal of Rotation Direction
Authors: Li Qingzhao , Ibaraki Soichi , Wang Wei
Published: August 2021

The five-axis machining of a free-form surface often contains the reversal of a rotary axis’ rotation direction with linear axis synchronized with it. This paper proposes a new machining test to quantitatively evaluate the influence of the reversal of rotation direction on the surface geometry and roughness. In the five-axis machining, the trajectory of tool position and orientation is first given in the workpiece coordinate system (WCS) by the computer-aided manufacturing (cam) software, and the computerized numerical control (CNC) system converts it to the machine coordinate system (MCS) to calculate command trajectories. This paper clarifies that the tool path smoothing in the MCS can potentially cause a large contour error because of the dynamic synchronization error of rotary and linear axes. Although some academic works in the literature presented the smoothing in the WCS, many commercial CNC systems still employ the smoothing in the MCS, partly because machine tool users or makers do not clearly see how significant this influence can be on the machining accuracy. The proposed machining test enables a user to quantitatively evaluate it. The machining experiment shows that the geometric error of the finished test piece was as large as 0.16 mm under the conventional smoothing in a commercial CNC system, which can be significantly larger than the influence of other typical geometric errors of a five-axis machine tool. This paper shows, by numerical simulation, that the smoothing in the WCS can completely eliminate this contour error.
Effect of Shock Wave Behavior on Unsteady Aerodynamic Characteristics of Oscillating Transonic Compressor Cascade
Authors: Gan Jiuliang , Watanabe Toshinori , Himeno Takehiro
Published: August 2021

The unsteady behavior of the shock wave was studied in an oscillating transonic compressor cascade. The experimental measurement and corresponding numerical simulation were conducted on the cascade with different shock patterns based on influence coefficient method. The unsteady pressure distribution on blade surface was measured with fast-response pressure-sensitive paint (PSP) to capture the unsteady aerodynamic force as well as the shock wave movement. It was found that the movement of shock waves in the neighboring flow passages of the oscillating blade was almost antiphase between the two shock patterns, namely, the double shocks pattern and the merged shock pattern. It was also found that the amplitude of the unsteady pressure caused by the passage shock wave was very large under the merged shock pattern compared with the double shocks pattern. The stability of blade vibration was also analyzed for both shock patterns including three-dimensional flow effect. These findings were thought to shed light on the fundamental understanding of the unsteady aerodynamic characteristics of oscillating cascade caused by the shock wave behavior.
Flocking Control of Multi-Agent Systems With Permanent Obstacles in Strictly Confined Environments
Authors: Wang Fengchen , Chen Yan
Published: August 2021

Considering the application of flocking control on connected and automated vehicle (CAV) systems, the persistent interactions between CAVs (flocking agents) and road boundaries (permanent obstacles) are critical due to flocking constraints in a strictly confined environment. However, the existing flocking theories attempt to model and animate natural flocks by considering temporary obstacles, which only describe interactions between agents and obstacles that would eventually disappear during flocking. This paper proposes a novel flocking control algorithm to extend existing flocking theories and guarantee the desired flocking coordination of multi-agent systems (e.g., CAV systems) with permanent obstacles (constraints). By analyzing comprehensive behaviors of flocks via Hamiltonian functions, a zero-sum obstacle condition is developed to ensure the satisfaction of permanent obstacle avoidance. Then, an additional control term representing the resultant forces of permanent obstacles is introduced to tackle interactions between agents and permanent obstacles. Demonstrated and compared through simulation results, a CAV system steered by the proposed flocking control protocol can successfully achieve the desired flocking behaviors with permanent obstacles avoidance in a three-lane traffic environment, which is failed by existing flocking control theories solely considering temporary obstacles.
Lethal and sublethal effects of Azadirachta indica-based products on Tetranychus neocaledonicus (Acari: Tetranychidae)
Authors: Santos Mayara Fernandes dos , Silva Paulo Roberto Ramalho , Briozo Marcus Eugênio O. , Silva Joesley Frazão , Melo Junior Luiz Carlos de , Barbosa Douglas Rafael e Silva , França Solange Maria de
Published: August 2021

The objective of this study is to evaluate the toxicity, repellency, and the ovicidal, residual, and sublethal effects of different neem-based commercial formulations on the red mite Tetranychus neocaledonicus André (1933) reared in the laboratory on lima bean (Phaseolus lunatus L.). To evaluate the toxicity on adult females of T. neocaledonicus, different concentrations of Natural Neem® (NN), Off-Neem® (ON), Nim-I-GO® (NG), and Azamax® (AZ) were defined from preliminary tests. The mortality and toxicity ratio were evaluated 48 h after application of the lethal concentrations (LC50s and LC95s). The repellent effect was verified through a two-choice test. The concentration used was the LC50 of the products calculated in the toxicity test. The number of mites attracted, the repellency index (RI), and the percentage of repellency of each product were calculated. The ovicidal effect after application of the LC50s and LC95s of each product and egg viability were observed. To evaluate the residual efficiency, the plants were sprayed with LC50 and LC95 of the products and the leaves were subsequently harvested at 24, 48, and 96h after the application of the products to evaluate mortality and oviposition reduction (PR - percentage of reduction). The sublethal effects were evaluated by applying the LC30 of the products (AZ, NG) to newly emerged females, whose survival and oviposition were evaluated daily. The determined LC50s were 0.39; 0.48; 0.68; and 1.39% for AZ, ON, NN, and NG, respectively. Considering the LC50, AZ was the most toxic product followed by ON, whereas the established LC95s were 2.20; 3.74; 6.10; and 7.98% for NN, ON, AZ, and NG, respectively. All tested products were classified as repellents for adult females of T. neocaledonicus. The eggs of T. neocaledonicus treated with the LC95s of the products had their viabilities inhibited. However, when using the LC50s, NN provided the lowest viability (8.0%), being considered the most toxic for eggs. The products presented reduced residual effect probably due to their rapid degradation. The mites treated with sublethal concentrations showed an average survival in days of 25.43, 28.35, and 29.20 for the treatments with Azamax®, control (untreated), and Nim-I-GO®, respectively. Relatively high oviposition rates in the first weeks decreased until the end of their life cycle. The life history of T. neocaledonicus is affected by sublethal concentrations of neem-based products. It was concluded that the tested products demonstrated acaricidal potential in the control of T. neocaledonicus on P. lunatus, presenting toxicity and repellent and ovicidal effect, although residual and sublethal effects were less significant.
Fire-induced loss of the world’s most biodiverse forests in Latin America
Authors: Armenteras Dolors , Dávalos Liliana M. , Barreto Joan S. , Miranda Alejandro , Hernández-Moreno Angela , Zamorano-Elgueta Carlos , González-Delgado Tania M. , Meza-Elizalde María C. , Retana Javier
Published: August 2021

The quantitative signal for the association of fires and land cover change is strong and the impact of frequent fires is vast.
Dating correlated microlayers in oxalate accretions from rock art shelters: New archives of paleoenvironments and human activity
Authors: Green Helen , Gleadow Andrew , Levchenko Vladimir A. , Finch Damien , Myers Cecilia , McGovern Jenna , Heaney Pauline , Pickering Robyn
Published: August 2021

Radiocarbon dating of layered rocks may provide new insight into past climates and human activity in Australia’s Kimberley region.
Jones matrix holography with metasurfaces
Authors: Rubin Noah A. , Zaidi Aun , Dorrah Ahmed H. , Shi Zhujun , Capasso Federico
Published: August 2021

A new mathematical framework uncovers overlooked possibilities for polarization-dependent metasurfaces.
Electronically reconfigurable complex oxide heterostructure freestanding membranes
Authors: Eom Kitae , Yu Muqing , Seo Jinsol , Yang Dengyu , Lee Hyungwoo , Lee Jung-Woo , Irvin Patrick , Oh Sang Ho , Levy Jeremy , Eom Chang-Beom
Published: August 2021

Freestanding membranes of electronically reconfigurable complex oxide heterostructure are demonstrated.
Solitary fibrous tumour of mediastinum: an often asymptomatic neoplasm
Authors: Sexton Gerard , McLoughlin Joseph , Burke Louise , Doddakula Kishore
Published: August 2021

Solitary fibrous tumours (SFTs) are rare neoplasms derived from mesenchymal cell lines. They are often asymptomatic, follow an indolent growth pattern and are more often benign than malignant. Here, we present a case of a very large, asymptomatic mediastinal SFT in an otherwise healthy man. A 67-year-old Irish man was referred for workup of an asymptomatic murmur. Auscultation of the lung fields revealed diminished breath sounds on the right side. Chest X-ray identified a 20 cm mass localised within the thorax. CT of the thorax confirmed a pleural based, solid lesion with no local invasion. CT-guided core biopsies were reported as consistent with SFT. Primary excision of the lesion was undertaken via median sternotomy. Histological examination confirmed a diagnosis of SFT. The patient remains well at this time. Primary excisive surgery is a safe and effective treatment modality for SFTs.
Use of ASD closure device for the sealing of false lumen entry in the ascending aorta after dissection Type A surgical repair
Authors: Petrov Ivo Spasov , Stankov Zoran Iovan , Boychev Damyan Boychev
Published: August 2021

We present a case of a persistent false lumen after ascending aorta replacement due to Stanford Type A dissection treated by endovascular means. The main entry tear was occluded with an atrial septal defect closure device, sealing the false lumen. A total of five additional stents were implanted to centralise and secure the flow in the true lumen. CT scan at 6-month follow-up showed excellent results with a decreased total aortic diameter and thrombosed false lumen.
Gastric ischaemia: a rare cause of gastric ulcers
Authors: Dutta Arunima , Byreddi Laxman Yashwant , Kesari Kavitha , Buchupalle Priyanka
Published: August 2021

Gastric ulcers secondary to gastric ischaemia is rare because of the rich blood supply of the stomach. We present a case where a patient with history of atherosclerotic vascular disease (ASCVD) presented with unintentional weight loss and failure to thrive for several months. Initial imaging studies ruled out any active malignancy. Oesophagogastroduodenoscopy revealed multiple shallow gastric ulcers. CT angiography was performed in later course of the hospital stay, which demonstrated a high-grade stenosis at the origin of both the superior mesenteric artery and the coeliac trunk. This combination stenosis is a rare finding, which can lead to ischaemia of the stomach by blocking the stomach’s dual blood supply. Although the patient underwent revascularisation attempt with stent placement, she expired due to critical postoperative condition. This case signifies the importance of keeping a low threshold for suspicion for gastric ischaemia in patients with ASCVD risk factors and unexplained weight loss.
Spontaneous attachment of complex Descemet’s membrane detachment following multiple failed interventions
Authors: Gupta Shikha , Mahalingam Karthikeyan , Agarwal Tushar
Published: August 2021

We describe a case with complex Descemet membrane detachment (DMD) which persisted despite initial two failed surgical attempts to appose the ocular tissues. However, over time, tissue alignment was obtained spontaneously. A 60-year-old woman, operated trabeculectomy, had a total DMD intraoperatively during a complicated cataract surgery. Initial attempt to DM repositioning with intracameral air injection failed. Anterior Segment Optical Coherence Tomography (ASOCT) showed detachment of both DM and pre-Descemet’s layer (PDL). After consultation with a corneal surgeon, patient was again attempted for Intra-operative Optical Coherence Tomography (iOCT)-guided settlement of DMD with intracameral air which again failed. So, the patient was registered for lamellar corneal transplant, but at 3 months follow-up, DM had spontaneously attached, confirmed on ASOCT. This case shows for the first time that even complex DMDs involving PDL, can spontaneously appose despite failed surgical interventions.