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ABSTRACT3-Aroylflavones, a new synthesized group of flavones, have been recently studied via Baker–Venkataraman rearrangement under ‘one-pot’ or sequential ‘one-pot’ reaction conditions. Choline hydroxide, an inexpensive, easily prepared, and green homogeneous catalyst has been found to be the most efficient catalyst among several base catalysts such as KOH/pyridine, KOH/triethylamine, and CaO-ES/triethylamine in the sequential ‘one-pot’ synthesis of 3-aroylflavones. Moreover, the catalyst’s efficiency, and high recyclability to six times without considerable loss of 3-aroylflavones have enhanced the importance of the procedure. Furthermore, 1D-NMR, 2D-NMR, and HRMS have also been used to elucidate the structures of synthesized compounds.

Acetylation of α-tubulin at the lysine 40 residue (αK40) by αTAT1/MEC-17 acetyltransferase modulates microtubule properties and occurs in most eukaryotic cells. Previous literatures suggest that acetylated microtubules are more stable and damage resistant. αK40 acetylation is the only known microtubule luminal post-translational modification site. The luminal location suggests that the modification tunes the lateral interaction of protofilaments inside the microtubule. In this study, we examined the effect of tubulin acetylation on the doublet microtubule (DMT) in the cilia of Tetrahymena thermophila using a combination of cryo-electron microscopy, molecular dynamics, and mass spectrometry. We found that αK40 acetylation exerts a small-scale effect on the DMT structure and stability by influencing the lateral rotational angle. In addition, comparative mass spectrometry revealed a link between αK40 acetylation and phosphorylation in cilia.

Abstract Cilia are hairlike protrusions that project from the surface of eukaryotic cells and play key roles in cell signaling and motility. Ciliary motility is regulated by the conserved nexin-dynein regulatory complex (N-DRC), which links adjacent doublet microtubules and regulates and coordinates the activity of outer doublet complexes. Despite its critical role in cilia motility, the assembly and molecular basis of the regulatory mechanism are poorly understood. Here, using cryo-electron microscopy in conjunction with biochemical cross-linking and integrative modeling, we localize 12 DRC subunits in the N-DRC structure of Tetrahymena thermophila. We also find that the CCDC96/113 complex is in close contact with the DRC9/10 in the linker region. In addition, we reveal that the N-DRC is associated with a network of coiled-coil proteins that most likely mediates N-DRC regulatory activity.

Abstract Cilia are ubiquitous eukaryotic organelles responsible for cellular motility and sensory functions. The ciliary axoneme is a microtubule-based cytoskeleton consisting of two central singlets and nine outer doublet microtubules. Cryo-electron microscopy-based studies have revealed a complex network inside the lumen of both tubules composed of microtubule-inner proteins (MIPs). However, the functions of most MIPs remain unknown. Here, we present single-particle cryo-EM-based analyses of the Tetrahymena thermophila native doublet microtubule and identify 42 MIPs. These data shed light on the evolutionarily conserved and diversified roles of MIPs. In addition, we identified MIPs potentially responsible for the assembly and stability of the doublet outer junction. Knockout of the evolutionarily conserved outer junction component CFAP77 moderately diminishes Tetrahymena swimming speed and beat frequency, indicating the important role of CFAP77 and outer junction stability in cilia beating generation and/or regulation.

Transformer-based architectures have recently gained significant attention in various computer vision tasks. Their ability to capture non-local dependencies and intricate characteristics makes them a promising complement to CNNs. However, their application in parking slot detection tasks is still limited. Thus, this paper proposes an appropriate way to apply transformer-based architectures to parking slot detection tasks. The proposed method adopts the Detection Transformer (DETR) architecture, which employs a standard transformer encoder-decoder framework. Since this approach requires a long training time, this paper suggests utilizing fixed anchor points to replace object queries in the original DETR architecture. Each anchor point is assigned a known location and focuses only on a predefined area of the feature map, resulting in a considerable reduction in training time. In addition, this paper suggests using a more suitable and efficient two-point parking slot representation to improve detection performance. In experiments, the proposed method was evaluated with the public large-scale SNU dataset and showed comparable detection performance to the state-of-the-art CNN-based methods with 96.11% recall and 96.61% precision.

Although it is well-known that the two-stage approach outperforms the one-stage approach in general object detection, they have similarly performed in parking slot detection so far. We consider this is because the two-stage approach has not yet been adequately specialized for parking slot detection. Thus, this paper proposes a highly specialized two-stage parking slot detector that uses region-specific multi-scale feature extraction. In the first stage, the proposed method finds the entrance of the parking slot as a region proposal by estimating its center, length, and orientation. The second stage of this method designates specific regions that most contain the desired information and extracts features from them. That is, features for the location and orientation are separately extracted from only the specific regions that most contain the locational and orientational information. In addition, multi-resolution feature maps are utilized to increase both positioning and classification accuracies. A high-resolution feature map is used to extract detailed information (location and orientation), while another low-resolution feature map is used to extract semantic information (type and occupancy). In experiments, the proposed method was quantitatively evaluated with two large-scale public parking slot detection datasets: SNU and PS2.0 datasets. In SNU dataset, the proposed method achieved state-of-the-art performance with 95.75% recall and 95.78% precision.

Abstract Intraflagellar transport for ciliary assembly and maintenance is driven by dynein and kinesins specific to the cilia. It has been shown that anterograde and retrograde transports run on different regions of the doublet microtubule, i.e., separate train tracks. However, little is known about the regulatory mechanism of this selective process. Since the doublet microtubule is known to display specific post-translational modifications of tubulins, i.e., “tubulin code”, for molecular motor regulations, we investigated the motility of ciliary specific dynein-2 under different post-translational modification by coarse-grained molecular dynamics. Our setup allows us to simulate the landing behaviors of dynein-2 on un-modified, detyrosinated, poly-glutamylated and poly-glycylated microtubules in silico. Our study revealed that poly-glutamylation can play an inhibitory effect on dynein-2 motility. Our result indicates that poly-glutamylation of the B-tubule of the doublet microtubule can be used as an efficient means to target retrograde intraflagellar transport onto the A-tubule.

AC model is known as the most accurate model for transmission expansion planning (TEP) problem. However, finding an optimal solution is still a difficult task due to the complex, non-linear, and non-convex nature of the ACTEP. In this study, a new hybridization of Differential Evolution (DE) and Zebra Optimization Algorithm (ZOA) algorithms, called DE-ZOA, is proposed to solve the ACTEP problem. The main idea of the hybrid algorithm is to improve the exploitation strategy of the DE algorithm based on the best individual in the population, which is inspired by the ZOA algorithm. The results given by the proposed DE-ZOA algorithm are compared to the original DE, ZOA, and other existing algorithms in both Graver 6 bus and IEEE 24 bus systems. The results show that the total cost obtained by the proposed DE-ZOA algorithm is smaller than 44.33% and 0.66% compared to the ZOA and DE algorithms in IEEE 24 bus systems. The proposed method illustrates the effectiveness of utilizing DE-ZOA algorithm to find optimal solution for the ACTEP problem. [ABSTRACT FROM AUTHOR]

Traditionally, analytical chemistry and diagnosis relied on wet laboratories and skilled professionals utilizing sophisticated instruments for sample handling and analysis. However, with the development of novel materials and sensing techniques, there has been a significant shift towards the use of standalone sensors, allowing tests to be conducted on-site or even in real time, leading to cost- and time-efficiency. With their widespread adoption globally, smartphones have emerged as an ideal platform for such sensors, boasting extensive sensor capabilities, advanced processing power, and communication functionalities. Smartphone-based assays make use of optical and electrochemical sensors, utilizing built-in cameras, ambient light sensors, and other features for optical sensing, while the micro-USB port, Bluetooth, and wireless connection facilitate data transmission and analog voltage application for electrochemical sensing. Previous overview papers have explored smartphone-based sensing in specific domains; this review provides a comprehensive examination of recent advancements in smartphone-based sensors, encompassing both optical and electrochemical sensing methods. The review provides the fundamental principles of these sensors and their implementation using smartphones, showcases recent applications, and presents innovative designs that take advantage of the inherent functionalities and sensor capabilities of smartphones. The review concludes by offering an outlook on the prospects of smartphone-based sensing and includes a reflective section emphasizing the potential impact of sensors in chemical and biological analyses. This comprehensive resource aims to provide information to researchers and practitioners interested in using smartphones for cutting-edge analytical methodologies.

INTRODUCTION: Data on HIV treatment outcomes in people who inject drugs (PWID) in the Asia-Pacific are sparse despite the high burden of drug use. We assessed immunological and virological responses, AIDS-defining events and mortality among PWID receiving antiretroviral therapy (ART). METHODS: We investigated HIV treatment outcomes among people who acquired HIV via injecting drug use in the TREAT Asia HIV Observational Database (TAHOD) between January 2003 and March 2019. Trends in CD4 count and viral suppression (VS, HIV viral load RESULTS: Of 622 PWID from 12 countries in the Asia-Pacific, 93% were male and the median age at ART initiation was 31 years (IQR, 28 to 34). The median pre-ART CD4 count was 71 cells/[micro]L. CD4 counts increased over time, with a mean difference of 401 (95% CI, 372 to 457) cells/[micro]L at year-10 (n = 78). Higher follow-up HIV viral load and pre-ART CD4 counts were associated with smaller increases in CD4 counts. Among 361 PWID with [greater than or equal to]1 viral load after six months on ART, proportions with VS were 82%, 88% and 93% at 2- 5- and 10-years following ART initiation. There were 52 new AIDS-defining events and 50 deaths during 3347 person-years of follow-up (PYS) (incidence 3.05/100 PYS, 95% CI, 2.51 to 3.70). Previous AIDS or TB diagnosis, lower current CD4 count and adherence CONCLUSIONS: Despite improved outcomes over time, our findings highlight the need for rapid ART initiation and adherence support among PWID within Asian settings. Keywords: people who inject drugs; treatment outcomes; CD4 recovery; viral suppression; tuberculosis; HIV/AIDS; Asia-Pacific, 1 | INTRODUCTION Globally, injecting drug use is a major public health concern leading to substantial health burden and transmission risk of blood-borne infections from injecting equipment sharing behaviours. In [...]

: Introduction: Interruptions in treatment pose risks for people with HIV (PWH) and threaten progress in ending the HIV epidemic; however, the COVID‐19 pandemic's impact on HIV service delivery across diverse settings is not broadly documented. Methods: From September 2020 to March 2021, the International epidemiology Databases to Evaluate AIDS (IeDEA) research consortium surveyed 238 HIV care sites across seven geographic regions to document constraints in HIV service delivery during the first year of the pandemic and strategies for ensuring care continuity for PWH. Descriptive statistics were stratified by national HIV prevalence ( Results: Questions about pandemic‐related consequences for HIV care were completed by 225 (95%) sites in 42 countries with low (n = 82), medium (n = 86) and high (n = 57) HIV prevalence, including low‐ (n = 57), lower‐middle (n = 79), upper‐middle (n = 39) and high‐ (n = 50) income countries. Most sites reported being subject to pandemic‐related restrictions on travel, service provision or other operations (75%), and experiencing negative impacts (76%) on clinic operations, including decreased hours/days, reduced provider availability, clinic reconfiguration for COVID‐19 services, record‐keeping interruptions and suspension of partner support. Almost all sites in low‐prevalence and high‐income countries reported increased use of telemedicine (85% and 100%, respectively), compared with less than half of sites in high‐prevalence and lower‐income settings. Few sites in high‐prevalence settings (2%) reported suspending antiretroviral therapy (ART) clinic services, and many reported adopting mitigation strategies to support adherence, including multi‐month dispensing of ART (95%) and designating community ART pick‐up points (44%). While few sites (5%) reported stockouts of first‐line ART regimens, 10–11% reported stockouts of second‐ and third‐line regimens, respectively, primarily in high‐prevalence and lower‐income settings. Interruptions in HIV viral load (VL) testing included suspension of testing (22%), longer turnaround times (41%) and supply/reagent stockouts (22%), but did not differ across settings. Conclusions: While many sites in high HIV prevalence settings and lower‐income countries reported introducing or expanding measures to support treatment adherence and continuity of care, the COVID‐19 pandemic resulted in disruptions to VL testing and ART supply chains that may negatively affect the quality of HIV care in these settings., INTRODUCTION The COVID‐19 pandemic has had major direct and indirect impacts on population health globally, through disruptions in the accessibility and quality of basic health services [1], in supply chains [...]

Congestion management is one of the most important issues in power system operation, especially in competitive electricity markets. The main aim of Congestion Management (CM) is to eliminate congestion in transmission lines. The most common technique to deal with the CM problem is re-dispatching the generator. However, finding an optimal solution for the CM problem constitutes a challenge for many researchers. Recently, a new biologically inspired metaheuristic algorithm, called Circulatory System Based Optimization (CSBO), was developed and proven to be effective in handling optimization issues. The CSBO algorithm was applied to solve the CM problem for the IEEE-30 bus system in two different cases. The former was compared with the Crayfish Optimization Algorithm (COA), Artificial Rabbits Optimization (ARO), Improved Grey Wolf Optimizer (I-GWO), and other existing methods. The simulation results revealed that the cost obtained from the proposed CSBO algorithm was lower than 14.5%, 11.31%, 9.97%, and 4% compared to PSO, FPA, FFA, and ALO. In addition, the stability of the proposed algorithm was higher than that of the other methods after 30 trials. [ABSTRACT FROM AUTHOR]

Here, the authors present two local methods for analyzing cryo-EM maps: LocSpiral and LocBSharpen that enhance high-resolution features of cryoEM maps, while preventing map distortions. They also introduce LocBFactor and LocOccupancy, which allow obtaining local B-factors and electron density occupancy maps from cryo-EM reconstructions and the authors demonstrate that these methods improve the interpretability and analysis of cryo-EM maps using different test cases among them recent SARS-CoV-2 spike glycoprotein structures.

Understanding the biomolecular corona is of key importance to nanomedicine. Here, the authors report on cryo-electron and tomographic imaging of the corona formed on model nanoparticles and the 3D reconstruction of the corona to study the distribution and association of the biomolecules with the nanoparticle.

This study explored methods to evaluate the test engine characteristics operated based on the reactivity controlled compression ignition (RCCI) technology to reduce fuel consumption and exhaust emissions, especially PM and NOx. Consequently, gasoline and diesel, respectively, considered as the low reactivity fuel (LRF) and high reactivity fuel (HRF), are injected in the intake manifold and combustion chamber. The experimental procedure is conducted at a constant speed of 2000 rpm, and brake mean effective pressure (BMEP) from low load 0.84 bar to high load 4.24 bar. The injection strategy is varied according to the engine loads. Indeed, at the low and medium engine load condition, the diesel fuel is injected double injection pulse, at the high load, the diesel fuel is injected single injection pulse. The injection timing is advanced from the top dead center (TDC) until knocking happens or the coefficient of variation (COV) higher than 10%, and maximum advanced injection timing is 65 crank angle degree (℃A) before the top dead center (BTDC). The results of advanced injection timing show that limit of advanced timing in low load is COV while at high load is knocking; at medium load, the diesel injection timing can be advanced to 65℃A BTDC. The exhaust emissions of CO and HC are higher than conventional diesel engines, while soot is hugely lower in all operating points. NOx emission is much dependent on injection timing, at 10 to 20℃A BTDC NOx highest, and approximately to the conventional diesel engine, NOx reduction when injection timing advanced.

Caries prevention is essential for oral hygiene. A fully automated procedure that reduces human labor and human error is needed. This paper presents a fully automated method that segments tooth regions of interest from a panoramic radiograph to diagnose caries. A patient’s panoramic oral radiograph, which can be taken at any dental facility, is first segmented into several segments of individual teeth. Then, informative features are extracted from the teeth using a pre-trained deep learning network such as VGG, Resnet, or Xception. Each extracted feature is learned by a classification model such as random forest, k-nearest neighbor, or support vector machine. The prediction of each classifier model is considered as an individual opinion that contributes to the final diagnosis, which is decided by a majority voting method. The proposed method achieved an accuracy of 93.58%, a sensitivity of 93.91%, and a specificity of 93.33%, making it promising for widespread implementation. The proposed method, which outperforms existing methods in terms of reliability, and can facilitate dental diagnosis and reduce the need for tedious procedures.

Over the years, studying the ultrastructure of the eukaryotic cilia/flagella using electron microscopy (EM) has contributed significantly toward our understanding of ciliary function. Major complexes in the cilia, such as inner and outer dynein arms, radial spokes, and dynein regulatory complexes, were originally discovered by EM. Classical resin-embedding EM or cryo-electron tomography can be performed directly on the isolated cilia or in some cases, cilia directly attached to the cell body. Recently, single particle cryo-EM has emerged as a powerful structural technique to elucidate high-resolution structures of macromolecular complexes; however, single particle cryo-EM requires non-overlapping complexes, i.e., the doublet microtubule of the cilia. Here, we present a protocol to separate the doublet microtubule from the isolated cilia bundle of two species, Tetrahymena thermophila and Chlamydomonas reinhardtii, using ATP reactivation and sonication. Our approach produces good distribution and random orientation of the doublet microtubule fragments, which is suitable for single particle cryo-EM analysis.