Similar Functions Research Articles

Tricks of the puppet masters: morphological adaptations to the interaction with nervous system underlying host manipulation by rhizocephalan barnacle Polyascus polygeneus.

Rhizocephalan interaction with their decapod hosts is a superb example of host manipulation. These parasites are able to alter the host's physiology and behavior. Host-parasite interaction is performed, presumably, via special modified rootlets invading the ventral ganglions. In this study, we focus on the morphology and ultrastructure of these special rootlets in Polyascus polygeneus (Lützen & Takahashi, 1997), family Polyascidae, invading the neuropil of the host's nervous tissue. The ventral ganglionic mass of the infected crabs were fixed, and the observed sites of the host-parasite interplay were studied using transmission electron microscopy, immunolabeling and confocal microscopy. The goblet-shaped organs present in the basal families of parasitic barnacles were presumably lost in a common ancestor of Polyascidae and crown "Akentrogonida", but the observed invasive rootlets appear to perform similar functions, including the synthesis of various substances which are transferred to the host's nervous tissue. Invasive rootlets significantly differ from trophic ones in cell layer composition and cuticle thickness. Numerous multilamellar bodies are present in the rootlets indicating the intrinsic cell rearrangement. The invasive rootlets of P. polygeneus are enlaced by the thin projections of glial cells. Thus, glial cells can be both the first hosts' respondents to the nervous tissue damage and the mediator of the rhizocephalan interaction with the nervous cells. One of the potential molecules engaged in the relationships of P.polygeneus and its host is serotonin, a neurotransmitter which is found exclusively in the invasive rootlets but not in trophic ones. Serotonin participates in different biological pathways in metazoans including the regulation of aggression in crustaceans, which is reduced in infected crabs. We conclude that rootlets associated with the host's nervous tissue are crucial for the regulation of host-parasite interplay and for evolution of the Rhizocephala.

BmPxt1 mediated immune response by regulating PGE2 in silkworm, Bombyx mori

Prostaglandins (PGs) mediates the immune response of insects to multiple stimuli. Mammalian cyclooxygenase (COXs) is a key enzyme in the synthesis of PGs, and peroxinectin (Pxt) may have similar functions in some sequenced insect genomes. As a representative of Lepidoptera, the silkworm also contains PGs, but its synthetic pathway is not clear. We cloned a full-length cDNA encoding a Pxt, designated as BmPxt1, from silkworm. Sequence alignment analysis showed that the protein encoded by BmPxt1 has a conserved domain similar to Pxts, and its catalytic site is shared with the Pxt of Manduca sexta, which also produces PGs. The expression of BmPxt1 gene was the highest in the hemocytes and was induced by Nuclear Polyhedrosis Virus (NPV) challenge in the detected tissues. Moreover, we found that dsPxt1 treatment deficiency down-regulated BmPxt1 transcript levels and efficiently inhibiting hemocyte-spreading and nodule formation in silkworm. Hemocyte-spreading, nodule formation, phenoloxidase (PO) and AMP genes (attacin, defencin and moricin) were also inhibited by aspirin, a COX inhibitor. Treatment by PGE2 but not arachidonic acid (AA) rescued the immunosuppression; PGs concentrations was also inhibited by aspirin. PGE2, but not AA, treatment rescued the PGs concentrations. The COX inhibitor, aspirin, impaired the innate immune response including nodulation, encapsulation, and melanization in silkworm, while PGE2, but not arachidonic acid (AA), partially reversed these effects of aspirin. Recombinant BmsPxt1 significantly induced PO activation in larvae hemolymph, PGs concentrations and encapsulation of agarose beads. Injection of recombinant BmsPxt1 into larvae resulted in increased transcript levels of AMP genes. Our results confirmed that BmPxt1 was involved in the synthesis of PGs in the innate immune response of silkworm larvae, and provided new information for the role of BmsPxt1 secreted by silkworm in activating PO and antimicrobial peptides.

Potential prognostic biomarkers of hepatocellular carcinoma based on 4D label-free quantitative proteomics analysis pilot investigation.

Hepatocellular carcinoma carries a poor prognosis and poses a serious threat to global health. Currently, there are few potential prognostic biomarkers available for the prognosis of hepatocellular carcinoma. This pilot study used 4D label-free quantitative proteomics to compare the proteomes of hepatocellular carcinoma and adjacent non-tumor tissue. A total of 66,075 peptides, 6363 identified proteins, and 772 differentially expressed proteins were identified in specimens from three hepatocellular carcinoma patients. Through functional enrichment analysis of differentially expressed proteins by Gene Ontology, KEGG pathway, and protein domain, we identified proteins with similar functions. Twelve differentially expressed proteins (RPL17, RPL27, RPL27A, RPS5, RPS16, RSL1D1, DDX18, RRP12, TARS2, YARS2, MARS2, and NARS1) were selected for identification and validation by parallel reaction monitoring. Subsequent Western blotting confirmed overexpression of RPL27, RPS16, and TARS2 in hepatocellular carcinoma compared to non-tumor tissue in 16 pairs of clinical samples. Analysis of The Cancer Genome Atlas datasets associated the increased expression of these proteins with poor prognosis. Tissue microarray revealed a negative association between high expression of RPL27 and TARS2 and the prognosis of hepatocellular carcinoma patients, although RPS16 was not significant. These data suggest that RPL27 and TARS2 play an important role in hepatocellular carcinoma progression and may be potential prognostic biomarkers of overall survival in hepatocellular carcinoma patients.

Long non-coding RNA APDC plays important regulatory roles in metabolism of bone and adipose tissues

ABSTRACT The long noncoding RNA (lncR) ANRIL in the human genome is an established genetic risk factor for atherosclerosis, periodontitis, diabetes, and cancer. However, the regulatory role of lncR-ANRIL in bone and adipose tissue metabolism remains unclear. To elucidate the function of lncRNA ANRIL in a mouse model, we investigated its ortholog, AK148321 (referred to as lncR-APDC), located on chr4 of the mouse genome, which is hypothesized to have similar biological functions to ANRIL. We initially revealed that lncR-APDC in mouse bone marrow cells (BMSCs) and lncR-ANRIL in human osteoblasts (hFOBs) are both increased during early osteogenesis. Subsequently, we examined the osteogenesis, adipogenesis, osteoclastogenesis function with lncR-APDC deletion/overexpression cell models. In vivo, we compared the phenotypic differences in bone and adipose tissue between APDC-KO and wild-type mice. Our findings demonstrated that lncR-APDC deficiency impaired osteogenesis while promoting adipogenesis and osteoclastogenesis. Conversely, the overexpression of lncR-APDC stimulated osteogenesis, but impaired adipogenesis and osteoclastogenesis. Furthermore, KDM6B was downregulated with lncR-APDC deficiency and upregulated with overexpression. Through binding-site analysis, we identified miR-99a as a potential target of lncR-APDC. The results suggest that lncR-APDC exerts its osteogenic function via miR-99a/KDM6B/Hox pathways. Additionally, osteoclasto-osteogenic imbalance was mediated by lncR-APDC through MAPK/p38 and TLR4/MyD88 activation. These findings highlight the pivotal role of lncR-APDC as a key regulator in bone and fat tissue metabolism. It shows potential therapeutic for addressing imbalances in osteogenesis, adipogenesis, and osteoclastogenesis.

Genome-Wide Identification, Characterization, and Expression Analysis under Abiotic Stresses of the UBP Gene Family in Rice (Oryza sativa L.)

The ubiquitin-specific protease (UBP) family represents a type of deubiquitinase (DUB) that plays a significant role in plant abiotic stress responses, growth, and development. Although UBP genes have been characterized in many species, a genome-wide systematic analysis and the potential functions under abiotic stresses have not yet been reported in rice (Oryza sativa L.). In this study, we identified 21 UBP gene family members in the genome of rice, all of which had UCH domains containing short but highly conserved Cys-box and His-box. The DUF4220 and DUF594 domains, which are found in monocotyledonous plants, were unique. Phylogenetic analysis suggested that OsUBP7 and OsUBP12 genes had the closest genetic relationships with AtUBP12 and AtUBP13, implying that OsUBP7 and OsUBP12 might have similar biological functions to AtUBP12 and AtUBP13. Synteny analysis revealed that OsUBP genes were expanded through segmental duplication under purifying selection. Meanwhile, they had closer evolutionary relationships with monocotyledonous plants. Additionally, all OsUBP genes had an ABRE cis-element, which was related to abscisic acid (ABA) stress hormone response. Protein interaction analysis suggested that OsUBP22 might modulate gene regulation through OsGCN5- and OsADA2-mediated chromatin modification, and OsUBP10 might regulate salt stress through modulating OsDNA2_4 stability. Specifically, the expression profiles and the transcriptional levels of 11 representative OsUBPs suggested the potential important functions of OsUBP9 and OsUBP17 under drought and cold stresses. Taken together, our study provided a systematic analysis of OsUBPs and preliminarily explored their potential roles under abiotic stresses. Our results lay a foundation for further research on the functions of the OsUBP gene family under abiotic stresses.

ConF: A Deep Learning Model Based on BiLSTM, CNN, and Cross Multi-Head Attention Mechanism for Noncoding RNA Family Prediction.

This paper presents ConF, a novel deep learning model designed for accurate and efficient prediction of noncoding RNA families. NcRNAs are essential functional RNA molecules involved in various cellular processes, including replication, transcription, and gene expression. Identifying ncRNA families is crucial for comprehensive RNA research, as ncRNAs within the same family often exhibit similar functionalities. Traditional experimental methods for identifying ncRNA families are time-consuming and labor-intensive. Computational approaches relying on annotated secondary structure data face limitations in handling complex structures like pseudoknots and have restricted applicability, resulting in suboptimal prediction performance. To overcome these challenges, ConF integrates mainstream techniques such as residual networks with dilated convolutions and cross multi-head attention mechanisms. By employing a combination of dual-layer convolutional networks and BiLSTM, ConF effectively captures intricate features embedded within RNA sequences. This feature extraction process leads to significantly improved prediction accuracy compared to existing methods. Experimental evaluations conducted using a single, publicly available dataset and applying ten-fold cross-validation demonstrate the superiority of ConF in terms of accuracy, sensitivity, and other performance metrics. Overall, ConF represents a promising solution for accurate and efficient ncRNA family prediction, addressing the limitations of traditional experimental and computational methods.

Integrated Network Analysis of microRNAs, mRNAs, and Proteins Reveals the Regulatory Interaction between hsa-mir-200b and CFL2 Associated with Advanced Stage and Poor Prognosis in Patients with Intestinal Gastric Cancer.

Intestinal gastric cancer (IGC) carcinogenesis results from a complex interplay between environmental and molecular factors, ultimately contributing to disease development. We used integrative bioinformatic analysis to investigate IGC high-throughput molecular data to uncover interactions among differentially expressed genes, microRNAs, and proteins and their roles in IGC. An integrated network was generated based on experimentally validated microRNA-gene/protein interaction data, with three regulatory circuits involved in a complex network contributing to IGC progression. Key regulators were determined, including 23 microRNA and 15 gene/protein hubs. The regulatory circuit networks were associated with hallmarks of cancer, e.g., cell death, apoptosis and the cell cycle, the immune response, and epithelial-to-mesenchymal transition, indicating that different mechanisms of gene regulation impact similar biological functions. Altered expression of hubs was related to the clinicopathological characteristics of IGC patients and showed good performance in discriminating tumors from adjacent nontumor tissues and in relation to T stage and overall survival (OS). Interestingly, expression of upregulated hub hsa-mir-200b and its downregulated target hub gene/protein CFL2 were related not only to pathological T staging and OS but also to changes during IGC carcinogenesis. Our study suggests that regulation of CFL2 by hsa-miR-200b is a dynamic process during tumor progression and that this control plays essential roles in IGC development. Overall, the results indicate that this regulatory interaction is an important component in IGC pathogenesis. Also, we identified a novel molecular interplay between microRNAs, proteins, and genes associated with IGC in a complex biological network and the hubs closely related to IGC carcinogenesis as potential biomarkers.

A framework for approximate product search using faceted navigation and user preference ranking

One of the problems that e-commerce users face is that the desired products are sometimes not available and Web shops fail to provide similar products due to their exclusive reliance on Boolean faceted search. User preferences are also often not taken into account. In order to address these problems, we present a novel framework specifically geared towards approximate faceted search within the product catalog of a Web shop. It is based on adaptations to the p-norm extended Boolean model, to account for the domain-specific characteristics of faceted search in an e-commerce environment. These e-commerce specific characteristics are, for example, the use of quantitative properties and the presence of user preferences. Our approach explores the concept of facet similarity functions in order to better match products to queries. In addition, the user preferences are used to assign importance weights to the query terms. Using a large-scale experimental setup based on real-world data, we conclude that the proposed algorithm outperforms the considered benchmark algorithms. Last, we have performed a user-based study in which we found that users who use our approach find more relevant products with less effort.

Integrin alpha 11 is cardioprotective post myocardial infarction, regulating infarct formation and collagen organization

Abstract Background Post Myocardial Infarction (MI), fibrosis and in particular collagen production is an important response in order to replace apoptotic cells within the injured area and stabilize the heart wall1. Cardiac fibroblasts in and around the infarct region under mechanical and biochemical stress transform into myofibroblasts, secreting collagen to help stabilize the infarct segment2. In the short term this is an appropriate response to avoid rupture and death3. However, Long term collagen deposition will increase ventricular stiffness reducing compliance leading to further cardiac dysfunction and heart failure4. Mechanical activation of collagen production and fibrosis is understood to be a significant mediator of cardiac fibrosis, yet the mechanisms controlling mechanical activation of fibrosis are not well understood5,6. Purpose Here, we sort to investigate the role of Integrin α11 in cardiac remodelling post MI, a collagen binding integrin which preferentially binds to type I collagen and, is significantly upregulated post MI4,7. Methods Fibroblast Conditional α11 knockout (KO) and Wildtype Littermates (WT) underwent either SHAM or left anterior descending aorta (LAD) ligation surgery. Cardiac function was assessed with echocardiography and pressure volume loops. Ventricle samples were processed for FFPE histological/immunohistochemical analysis with hematoxylin/eosin, Collagen I & III antibodies. Finally, Second Harmonic generation microscopy was undertaken to identify collagen organisation with previously validated CurveAlign and CT-Fire algorithms. Results α11KO and WT mice demonstrated similar cardiac function. There was evidence of basal structural differences as Collagen I (P<0.05) and III (P<0.0001) deposition was reduced along with cardiac myocyte size (P<0.0001) in α11KO mice. In response to LAD ligation α11KO mice had significantly worse mortality (∼57% v’s ∼22%, P<0.05) which, correlated with an increased MI size (WT=∼39%, α11KO=∼64% P<0.05). Cardiac function 2 days following ligation measured by echo demonstrated that Fractional Area Change (FAC) (23%±2 v’s 16%±2 P<0.05) and Cardiac Output (8.5ml±1 v’s 5ml±0.7, P<0.05) were significantly worse in α11 KO compared to WT mice. The reduced function persisted 4 weeks post ligation as FAC was significantly worse in α11KO mice (∼9%±2%, P<0.0001) compared to WT (∼19%±1%). Moreover, α11KO mice that survived MI had significantly more collagen I (P<0.0001) content in the remote, peri-infarct and infarct zone’s than that of WT along with a lack of hypertrophic response. Finally, Collagen alignment measured using SHG images with CurveAlign demonstrated collagen fibres had significantly less structural alignment in α11KO mice (P<0.05). Conclusion We demonstrate a cardioprotective role for Integrin α11 post myocardial infarction. Where, the lack of α11 leads to worsened mortality, larger MI, worsened cardiac function and impaired collagen organisation in the infarct post MI.

Comparative analysis of rumen metagenome, metatranscriptome, fermentation and methane yield in cattle and buffaloes fed on the same diet.

A study to compare the rumen microbial community composition, functional potential of the microbiota, methane (CH4) yield, and rumen fermentation was conducted in adult male cattle and buffaloes fed on the same diet. A total of 41 phyla, 169 orders, 374 families, and 1,376 microbial genera were identified in the study. Bacteroidetes and Firmicutes were the two most dominant bacterial phyla in both cattle and buffaloes. However, there was no difference in the abundance of Bacteroidetes and Firmicutes in the rumen metagenome of cattle and buffaloes. Based on the abundance, the Proteobacteria was the 3rd largest phylum in the metagenome, constituting 18-20% in both host species. Euryarchaeota was the most abundant phylum of the methanogens, whereas Methanobacteriales and Methanobrevibacter were the most abundant orders and genera in both species. The methanogen abundances were not different between the two host species. Like the metagenome, the difference between the compositional and functional abundances (metagenome vs. metatranscriptome) of the Bacteroidetes and Firmicutes was not significant, whereas the proteobacteria were functionally less active than their metagenomic composition. Contrary to the metagenome, the Euryarchaeota was the 3rd most functional phylum in the rumen and constituted ~15% of the metatranscriptome. Methanobacteriales were the most functional methanogens, accounting for more than 2/3rd of the total archaeal functionality. These results indicated that the methanogens from Euryarchaeota were functionally more active as compared to their compositional abundance. The CH4 yield (g/kg DMI), CH4 emission (g/kg DDM), dry matter (DM) intake, and rumen fermentation did not vary between the two host species. Overall, the study established a substantial difference between the compositional abundances and metabolic functionality of the rumen microbiota; however, feeding cattle and buffaloes on the same diet resulted in similar microbiota composition, metabolic functionality, and CH4 yield. Further studies are warranted to investigate the effect of different diets and environments on the composition and metabolic functionality of the rumen microbiota.

Populational genomic insights of Paraclostridium bifermentans as an emerging human pathogen.

Paraclostridium bifermentans (P.b) is an emerging human pathogen that is phylogenomically close to Paeniclostridium sordellii (P.s), while their populational genomic features and virulence capacity remain understudied. Here, we performed comparative genomic analyses of P.b and compared their pan-genomic features and virulence coding profiles to those of P.s. Our results revealed that P.b has a more plastic pangenome, a larger genome size, and a higher GC content than P.s. Interestingly, the P.b and P.s share similar core-genomic functions, but P.b encodes more functions in nutrient metabolism and energy conversion and fewer functions in host defense in their accessory-genomes. The P.b may initiate extracellular infection processes similar to those of P.s and Clostridium perfringens by encoding three toxin homologs (i.e., microbial collagenase, thiol-activated cytolysin, phospholipase C, which are involved in extracellular matrices degradation and membrane damaging) in their core-genomes. However, P.b is less toxic than the P.s by encoding fewer secretion toxins in the core-genome and fewer lethal toxins in the accessory-genome. Notably, P.b carries more toxins genes in their accessory-genomes, particularly those of plasmid origin. Moreover, three within-species and highly conserved plasmid groups, encoding virulence, gene acquisition, and adaptation, were carried by 25-33% of P.b strains and clustered by isolation source rather than geography. This study characterized the pan-genomic virulence features of P.b for the first time, and revealed that P. bifermentans is an emerging pathogen that can threaten human health in many aspects, emphasizing the importance of phenotypic and genomic characterizations of in situ clinical isolates.

Neuropeptide Y receptor Y2 (npy2r) deficiency reduces anxiety and increases food intake in Japanese medaka (Oryzias latipes).

Neuropeptide Y receptor Y2 (npy2r) is an important receptor gene involved in anxiety and feeding regulation in mammals. Since NPY receptors have different receptor gene deletions in mammals and teleost fish, it is not clear whether npy2r has the similar function in fish as in mammals. In this study, we used the CRISPR/Cas9 system to establish npy2r-deficient medaka (Oryzias latipes). Unexpectedly, the deletion of npy2r resulted in the npy2r +/- medaka were all-male, therefore, npy2r homozygous mutant lines could not be established. The deletion of npy2r increased the food intake in medaka, and the expression levels of appetite stimulating genes (agrp, npy) increased significantly, while the expression levels of anorexia factors (cck, pomc) decreased significantly. Moreover, the absence of npy2r significantly increased the total length and body weight of medaka. The mirror test and open field test showed that npy2r +/- medaka improved sociability and reduced anxiety-like behavior, qRT-PCR analysis showed that the expression levels of anxiety related genes (th1, th2, gr1, gr2, and mr) in npy2r +/- medaka were significantly decreased. So far, this is the first npy2r gene knockout model established in fish and demonstrates that npy2r plays an important role in the regulation of reproduction, feeding and anxiety in fish.

Abstract 17016: Mitral Valve Prolapse Induces Localized Left Ventricular Fibrosis in a Novel Large Animal Model

Background: Mitral valve prolapse (MVP) has recently been associated with localized left ventricular (LV) fibrosis linked to malignant arrhythmia and sudden cardiac death. However, fibrosis mechanisms remain unknown, with no large animal model to distinguish mechanical and genetic influences. Goals: We tested the hypothesis that surgically induced MVP leads to localized myocardial fibrosis in LV regions mechanically linked to the mitral valve, aiming to establish a reproducible large animal model of MVP as a platform for mechanistic studies. Methods: In 6 adolescent sheep, MVP was created surgically by replacing primary chordae tendineae to P2 with longer artificial chords. Intraoperative echocardiography and LV pressure-volume loops were obtained. After 7 months recovery, cardiac MRI with gadolinium and T1-mapping were done before end-of-study surgery with repeat echo and pressure-volume loops. Three sham surgery sheep were similarly studied. Myocardial samples from valve-linked papillary muscle and inferobasal LV and control septal regions were analyzed by histology. Bulk RNA was sequenced on samples from 3 MVP and 3 sham sheep. Results: All 6 MVP sheep showed pronounced localized LV fibrosis in valve-linked regions but not control regions on MRI, with replacement fibrosis by Masson’s trichrome stain. Sham sheep had no fibrosis, with similar LV function and contractility at end-of-study. RNA sequencing revealed gene expression differences between the two LV regions in MVP sheep and the valve-linked regions of MVP vs sham sheep. Conclusions: In a novel surgically created large animal model of MVP, localized fibrosis is induced in formerly healthy LV myocardium. This suggests a mechanical mechanism is sufficient to create the localized LV fibrosis associated with arrhythmia in MVP patients. This model provides a platform to study fibrosis mechanisms and investigate therapeutic approaches to avoid catastrophic events in MVP patients.

Abstract 16873: Takotsubo Variant is Associated With Worse Right and Left Ventricular Systolic Function Than Other Stress Cardiomyopathy Variants

Introduction: Stress cardiomyopathy (SCM) is usually associated with reduced systolic function on echocardiogram. However, the prevalence of systolic dysfunction between different variables of SCM has not been established. Hypothesis: Whether Takotsubo variant SCM is associated with worse systolic function compared to other SCM variants. Methods: We conducted a retrospective cohort study evaluating echocardiograms of all patients with SCM between 2010 and 2022 at Hennepin Healthcare, MN, USA. The diagnosis of SCM was made based on the International Takotsubo (InterTak) diagnostic criteria. Results: Between January 2010 and December 2022, 296 patients presented with SCM. The majority of patients (N= 173, 58.4%) had the apical (Takotsubo) variant, compared to 78 (26.3%) patients with the midventricular variant and 45 (15.2%) with the basal variant. The three groups had no significant difference in the left ventricular outflow tract and septal diameters. Patients with the apical variant had a lower ejection fraction on presentation compared to mid-ventricular and basal variants (28.1% vs. 36.8% and 35.7%, respectively, p<0.001). Patients with Takotsubo CM had the lowest cardiac output and cardiac index among the three groups ( table 1 ). Right ventricular systolic function, evaluated by Tricuspid Annular Plane Systolic Excursion (TAPSE), was lowest in patients with apical SCM (mean TASPE 1.58 cm, p=0.027). All patients had similar ejection fraction recovery at follow-up (mean EF > 55%, p=0.793, mean follow-up time < 4 weeks, p=0.913). Conclusion: Takotsubo variant is associated with worse right and left ventricular systolic function compared to other SCM variants, with similar systolic function recovery at follow-up.

Coupled Effects of Lorentz Force, Radiation, and Dissipation on the Dynamics of a Hybrid Nanofluid over an Exponential Stretching Sheet

The flow and heat transfer induced by an exponentially shrinking sheet with hybrid nanoparticles are investigated comprehensively in this paper. Nanoparticles are considered due to their unusual characteristics such as extraordinary thermal conductivity, which is significant in advanced nanotechnology, heat exchangers, material sciences, and electronics. The main objective of this research is to enhance heat transportation. The flow model is first transformed and simplified to a system of ordinary differential equations utilizing non-dimensional quantities and similarity functions. Then, the desired system is solved with the help of the Runge–Kutta numerical method and the shooting technique in MATLAB script. The results show that a stronger porosity parameter raises the temperature while diminishing the velocity. Additionally, they emphasize that augmentations in the magnetic parameter, Eckert number, radiation parameter, and the volume fractions of titanium dioxide and silver nanoparticles are all proportional to the temperature profile.

Thermal performance improvement of a circular tube-and-fin heat exchanger by ellipsoidal protrusions on fin surfaces

A novel fin stamped out with ellipsoidal protrusions is proposed to improve the performance of a circular tube-and-fin heat exchanger in this paper. The ellipsoidal protrusions have a similar function as the traditional plane or curved vortex generators that can generate longitudinal vortices in the flow channel. The effect of different attack angles of the ellipsoidal protrusions on the thermal performance of a circular tube-and-fin heat exchanger is numerically analyzed. The turbulent flow and heat transfer properties were investigated by Standard k-ε turbulence model with finite volume method. The results illustrated that the ellipsoidal protrusions can substantially improve the intensity of secondary flow and enhance the heat transfer. The ellipsoidal protrusions exhibited better heat transfer than the traditional vortex generators. Nu of the fin with ellipsoidal protrusions increased up to 31.73 % and 19.95 % compared with the smooth fin and the fin with vortex generators, respectively. Both Nu and f of the fin with ellipsoidal protrusions increased with the increase in attack angle. An optimum attack angle of 20° of the ellipsoidal protrusion existed for the highest thermal performance factor of 1.165. Fitted equations for Nu, f, and JF were provided for facilitating application to engineering.

A sustainable biomass-based electret for face mask and non-volatile transistor memory

An electret filter on the middle layer of disposable medical face masks has a similar function to the charge storage layer on the transistor memory devices. Both applications require a polymer electret to trap charges so that it could establish electrostatic attraction to effectively enhance the filtration efficiency of face mask or modulate the electrical behaviours of transistor memory. By virtue of that very same function, we demonstrate the charge storage performance and memory characteristics of transistor memory using the electret filters of face mask material, from the non-renewable polypropylene (PP) to the biomass-based polymers. We demonstrate dextrin, a biomass-derivative, as a sustainable alternative electret. Due to dextrin being produced natural starch products, it is a renewable material that is biocompatible and eco-friendly. Furthermore, by adding sodium methylsiliconate (SMS), the hydrophobic blended dextrin-SMS transistor memory can maintain inherent prolonged electrostatic charges for over 100 days along with relatively wide memory window of 39.5 V. Ultimately, the non-woven nanofiber electret filter using dextrin-SMS can be successfully produced using an industrial compatible electrospinning technique combined with the addition of polyethylene oxide (PEO) to improve the electrospinability of the mat filter and potentially utilized for future biodegradable face masks and green electronics.

Identification and expression analysis of LEA gene family members in pepper (Capsicum annuum L.).

Pepper (Capsicum annuum L.) is an economically important crop containing capsaicinoids in the seed and placenta, which has various culinary, medical, and industrial applications. Late embryogenesis abundant (LEA) proteins are a large group of hydrophilic proteins participating in the plant stress response and seed development. However, to date there have been no genome-wide analyses of the LEA gene family in pepper. In the present study, 82 LEA genes were identified in the C. annuum genome and classified into nine subfamilies. Most CaLEA genes contain few introns (≤ 2) and are unevenly distributed across 10 chromosomes. Eight pairs of tandem duplication genes and two pairs of segmental duplication genes were identified in the LEA gene family; these duplicated genes were highly conserved and may have performed similar functions during evolution. Expression profile analysis indicated that CaLEA genes exhibited different tissue expression patterns, especially during embryonic development and stress response, particularly in cold stress. Three out of five CaLEA genes showed induced expression upon cold treatment. In summary, we have comprehensively reviewed the LEA gene family in pepper, offering a new perspective on the evolution of this family.

Transfer learning in optimization: Interpretable self-organizing maps driven similarity indices to identify candidate source functions

In the design evolution of a product, designers often require solving similar functions repeatedly across different designs. These functions are usually related to each other and typically share topology, common features and physics. Thus, solving one function referred to as a source that characterizes a problem can yield knowledge that can be reused to solve other related function referred to as target. Re-purposing such shared knowledge, especially in cases of complex optimization, aids in faster convergence, more accurate solutions, and reduced computational costs, among others. The concept of transfer learning (TL) is built on this notion of passing the gained knowledge between related problems to lessen the algorithmic and/or modeling complexities. Transfer of knowledge between source and target that are not related leads to negative transfer circumstances, where the algorithm’s performance degrades on transferring. Hence, identifying a similar source to share the knowledge is of fundamental importance in transfer learning approaches. Literature has often skipped this step of identifying related or similar functions by artificially constructing functions or assuming apriori that the considered functions are similar to each other. Current work proposes to use interpretable self-organizing map and an image comparison technique to quantify the topological similarity between the source and the target. Metrics such as mean squares, structural similarity index, and Cosine similarity are used to quantify the level of similarity mathematically. The proposed approach is implemented on a suite of benchmark analytical functions with varying order, complexity, and dimensions, engineering examples, and real-world application functions. It is demonstrated that the proposed approach is able to identify appropriate source function for a given target, even when they are of varying dimensions. Results of engineering examples show that functions representing problems with similar physics are identified correctly. Hence, the proposed approach can be used to identify appropriate source functions for a given target, permitting transfer learning and thus accelerating convergence, and reducing computational cost.

A Multi-View Approach for Regional Parking Occupancy Prediction with Attention Mechanisms

The near-future parking space availability is informative for the formulation of parking-related policy in urban areas. Plenty of studies have contributed to the spatial–temporal prediction for parking occupancy by considering the adjacency between parking lots. However, their similarities in properties remain unspecific. For example, parking lots with similar functions, though not adjacent, usually have similar patterns of occupancy changes, which can help with the prediction as well. To fill the gap, this paper proposes a multi-view and attention-based approach for spatial–temporal parking occupancy prediction, namely hybrid graph convolution network with long short-term memory and temporal pattern attention (HGLT). In addition to the local view of adjacency, we construct a similarity matrix using the Pearson correlation coefficient between parking lots as the global view. Then, we design an integrated neural network focusing on graph structure and temporal pattern to assign proper weights to the different spatial features in both views. Comprehensive evaluations on a real-world dataset show that HGLT reduces prediction error by about 30.14% on average compared to other state-of-the-art models. Moreover, it is demonstrated that the global view is effective in predicting parking occupancy.