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Vision plays a major role in perceiving external stimuli and information in our daily lives. The neural mechanism of color vision is complicated, involving the co-ordinated functions of a variety of cells, such as retinal cells and lateral geniculate nucleus cells, as well as multiple levels of the visual cortex. In this work, we reviewed the history of experimental and theoretical studies on this issue, from the fundamental functions of the individual cells of the visual system to the coding in the transmission of neural signals and sophisticated brain processes at different levels. We discuss various hypotheses, models, and theories related to the color vision mechanism and present some suggestions for developing novel implanted devices that may help restore color vision in visually impaired people or introduce artificial color vision to those who need it.
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Implantable bioelectronics hold tremendous potential in the field of healthcare, yet the performance of these systems heavily relies on the interfaces between artificial machines and living tissues. In this paper, we discuss the recent developments of tethered interfaces, as well as those of non-tethered interfaces. Among them, systems that study neural activity receive significant attention due to their innovative developments and high relevance in contemporary research, but other functional types of interface systems are also explored to provide a comprehensive overview of the field. We also analyze the key considerations, including perforation site selection, fixing strategies, long-term retention, and wireless communication, highlighting the challenges and opportunities with stable, effective, and biocompatible interfaces. Furthermore, we propose a primitive model of biocompatible electrical and optical interfaces for implantable systems, which simultaneously possesses biocompatibility, stability, and convenience. Finally, we point out the future directions of interfacing strategies.
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Materiales Biocompatibles , Técnicas Biosensibles , Prótesis e Implantes , Materiales Biocompatibles/química , Humanos , Técnicas Biosensibles/instrumentación , Tecnología Inalámbrica , AnimalesRESUMEN
The assembly of complete and circularized mitochondrial genomes (mitogenomes) is essential for population genetics, phylogenetics and evolution studies. Recently, Song et al. developed a seed-free tool called MEANGS for de novo mitochondrial assembly from whole genome sequencing (WGS) data in animals, achieving highly accurate and intact assemblies. However, the suitability of this tool for marine fish remains unexplored. Additionally, we have concerns regarding the overlap sequences in their original results, which may impact downstream analyses. In this Letter to the Editor, the effectiveness of MEANGS in assembling mitogenomes of cartilaginous and ray-finned fish species was assessed. Moreover, we also discussed the appropriate utilization of MEANGS in mitogenome assembly, including the implementation of the data-cut function and circular detection module. Our observations indicated that with the utilization of these modules, MEANGS efficiently assembled complete and circularized mitogenomes, even when handling large WGS datasets. Therefore, we strongly recommend users employ the data-cut function and circular detection module when using MEANGS, as the former significantly reduces runtime and the latter aids in the removal of overlapped sequences for improved circularization. Furthermore, our findings suggested that approximately 2× coverage of clean WGS data was sufficient for MEANGS to assemble mitogenomes in marine fish species. Moreover, due to its seed-free nature, MEANGS can be deemed one of the most efficient software tools for assembling mitogenomes from animal WGS data, particularly in studies with limited species or genetic background information.
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Genoma Mitocondrial , Animales , Secuenciación Completa del Genoma/métodos , Programas Informáticos , FilogeniaRESUMEN
Fulminant myocarditis is an acute diffuse inflammatory disease of myocardium. It is characterized by acute onset, rapid progress and high risk of death. Its pathogenesis involves excessive immune activation of the innate immune system and formation of inflammatory storm. According to China's practical experience, the adoption of the "life support-based comprehensive treatment regimen" (with mechanical circulation support and immunomodulation therapy as the core) can significantly improve the survival rate and long-term prognosis. Special emphasis is placed on very early identification,very early diagnosis,very early prediction and very early treatment.
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Miocarditis , Miocarditis/diagnóstico , Miocarditis/terapia , Humanos , China , Adulto , Cardiología/métodos , Cardiología/normas , Pronóstico , Sociedades MédicasRESUMEN
BACKGROUND: Unsustained return of spontaneous circulation (ROSC) is a critical barrier to survival in cardiac arrest patients. This study examined whether end-tidal carbon dioxide (ETCO2) and pulse oximetry photoplethysmogram (POP) parameters can be used to identify unsustained ROSC. METHODS: We conducted a multicenter observational prospective cohort study of consecutive patients with cardiac arrest from 2013 to 2014. Patients' general information, ETCO2, and POP parameters were collected and statistically analyzed. RESULTS: The included 105 ROSC episodes (from 80 cardiac arrest patients) comprised 51 sustained ROSC episodes and 54 unsustained ROSC episodes. The 24-hour survival rate was significantly higher in the sustained ROSC group than in the unsustained ROSC group (29.2% vs. 9.4%, P<0.05). The logistic regression analysis showed that the difference between after and before ROSC in ETCO2 (ΔETCO2) and the difference between after and before ROCS in area under the curve of POP (ΔAUCp) were independently associated with sustained ROSC (odds ratio [OR]=0.931, 95% confidence interval [95% CI] 0.881-0.984, P=0.011 and OR=0.998, 95% CI 0.997-0.999, P<0.001). The area under the receiver operating characteristic curve of ΔETCO2, ΔAUCp, and the combination of both to predict unsustained ROSC were 0.752 (95% CI 0.660-0.844), 0.883 (95% CI 0.818-0.948), and 0.902 (95% CI 0.842-0.962), respectively. CONCLUSION: Patients with unsustained ROSC have a poor prognosis. The combination of ΔETCO2 and ΔAUCp showed significant predictive value for unsustained ROSC.
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In this study, we propose a high-throughput and low-cost automatic detection method based on deep learning to replace the inefficient manual counting of rapeseed siliques. First, a video is captured with a smartphone around the rapeseed plants in the silique stage. Feature point detection and matching based on SIFT operators are applied to the extracted video frames, and sparse point clouds are recovered using epipolar geometry and triangulation principles. The depth map is obtained by calculating the disparity of the matched images, and the dense point cloud is fused. The plant model of the whole rapeseed plant in the silique stage is reconstructed based on the structure-from-motion (SfM) algorithm, and the background is removed by using the passthrough filter. The downsampled 3D point cloud data is processed by the DGCNN network, and the point cloud is divided into two categories: sparse rapeseed canopy siliques and rapeseed stems. The sparse canopy siliques are then segmented from the original whole rapeseed siliques point cloud using the sparse-dense point cloud mapping method, which can effectively save running time and improve efficiency. Finally, Euclidean clustering segmentation is performed on the rapeseed canopy siliques, and the RANSAC algorithm is used to perform line segmentation on the connected siliques after clustering, obtaining the three-dimensional spatial position of each silique and counting the number of siliques. The proposed method was applied to identify 1457 siliques from 12 rapeseed plants, and the experimental results showed a recognition accuracy greater than 97.80%. The proposed method achieved good results in rapeseed silique recognition and provided a useful example for the application of deep learning networks in dense 3D point cloud segmentation.
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Continuous renal replacement therapy (CRRT) is widely used for treating critically-ill patients in the emergency department in China. Anticoagulant therapy is needed to prevent clotting in the extracorporeal circulation during CRRT. Regional citrate anticoagulation (RCA) has been shown to potentially be safer and more effective and is now recommended as the preferred anticoagulant method for CRRT. However, there is still a lack of unified standards for RCA management in the world, and there are many problems in using this method in clinical practice. The Emergency Medical Doctor Branch of the Chinese Medical Doctor Association (CMDA) organized a panel of domestic emergency medicine experts and international experts of CRRT to discuss RCA-related issues, including the advantages and disadvantages of RCA in CRRT anticoagulation, the principle of RCA, parameter settings for RCA, monitoring of RCA (mainly metabolic acid-base disorders), and special issues during RCA. Based on the latest available research evidence as well as the paneled experts' clinical experience, considering the generalizability, suitability, and potential resource utilization, while also balancing clinical advantages and disadvantages, a total of 16 guideline recommendations were formed from the experts' consensus.
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Citratos , Terapia de Reemplazo Renal Continuo , Humanos , Anticoagulantes/uso terapéutico , Citratos/uso terapéutico , Consenso , ChinaRESUMEN
OBJECTIVE: To survey treatment and prognosis of hyperkalemia patients in the emergency department and to analyze factors associated with all-cause in-hospital mortality. METHODS: We implemented electronic hospital information system, extracted demographic characteristics, underlying diseases, laboratory findings, potassium lowering therapy and prognosis of hyperkalemia patients [age ≥ 18 years, serum potassium (K+) concentration ≥ 5.5 mmol/L] in the emergency department of Peking Union hospital in Beijing between June 1st 2019 to May 31st 2020. The enrolled subjects were divided into the non-survival group and the survival group according to their prognosis. Univariate analysis and Cox regression model were adopted to analyze factors affecting all-cause in-hospital mortality of hyperkalemia patients. RESULTS: A total of 579 patients [median age 64 (22) years; 310 men (53.5%) and 269 women (46.5%)] with hyperkalemia were enrolled, among which, 317 (54.7%), 143 (24.7%) and 119 (20.6%) were mild, moderate, and severe hyperkalemia, respectively. 499 (86.20%) patients received potassium-lowering therapy, forty-four treatment regimens were administered. Insulin and glucose (I+G, 61.3%), diuretics (Diu, 57.2%), sodium bicarbonate (SB, 41.9%) and calcium gluconate/chloride (CA, 44.4%) were commonly used for the treatment of hyperkalemiain the emergency department. The combination of insulin and glucose, calcium gluconate/chloride, diuretics and sodium bicarbonate (I+G+CA+Diu+SB) was the most favored combined treatment regimen of hyperkalemia in the emergency department. The higher serum potassium concentration, the higher proportion of administrating combined treatment regimen and/or hemodialysis (HD) (the proportion of administrating combined treatment regimen in mild, moderate, and severe hyperkalemia patients were 58.4%, 82.5% and 94.8%; the proportion of administrating HD in mild, moderate, and severe hyperkalemia patients were 9.7%, 13.3% and 16.0%, respectively). The proportion of achievement of normokalaemia elevated as the kinds of potassium lowering treatment included in the combined treatment regimen increased. The proportion of achievement of normokalaemia was 100% in the combined treatment regimen including 6 kinds of potassium lowering therapy. Among various potassium lowering treatments, HD contributed to the highest rate of achievement of normokalaemia (93.8%). 111 of 579 (19.20%) hyperkalemia patients died in hospital. Cox regression model revealed that complicated with cardiac dysfunction predicted higher mortality [hazard ratio (HR) = 1.757, 95% confidence interval (95%CI) was 1.155-2.672, P = 0.009]. Achievement of normokalaemia and administration of diuretics attributed to lower mortality (HR = 0.248, 95%CI was 0.155-0.398, P = 0.000; HR = 0.335, 95%CI was 0.211-0.531, P = 0.000, respectively). CONCLUSIONS: Treatment of hyperkalemia in the emergency department were various. Complicated with cardiac dysfunction were associated with higher mortality. Achieving normokalaemia was associated with decreased mortality.
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Hiperpotasemia , Masculino , Humanos , Femenino , Persona de Mediana Edad , Adolescente , Hiperpotasemia/terapia , Hiperpotasemia/complicaciones , Bicarbonato de Sodio , Gluconato de Calcio , Cloruros , Potasio/análisis , Pronóstico , Insulina , Glucosa , Diuréticos , Servicio de Urgencia en HospitalRESUMEN
In this paper, a novel point cloud segmentation and completion framework is proposed to achieve high-quality leaf area measurement of melon seedlings. In particular, the input of our algorithm is the point cloud data collected by an Azure Kinect camera from the top view of the seedlings, and our method can enhance measurement accuracy from two aspects based on the acquired data. On the one hand, we propose a neighborhood space-constrained method to effectively filter out the hover points and outlier noise of the point cloud, which can enhance the quality of the point cloud data significantly. On the other hand, by leveraging the purely linear mixer mechanism, a new network named MIX-Net is developed to achieve segmentation and completion of the point cloud simultaneously. Different from previous methods that separate these two tasks, the proposed network can better balance these two tasks in a more definite and effective way, leading to satisfactory performance on these two tasks. The experimental results prove that our methods can outperform other competitors and provide more accurate measurement results. Specifically, for the seedling segmentation task, our method can obtain a 3.1% and 1.7% performance gain compared with PointNet++ and DGCNN, respectively. Meanwhile, the R2 of leaf area measurement improved from 0.87 to 0.93 and MSE decreased from 2.64 to 2.26 after leaf shading completion.
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In this work, we presented a novel encoding method for tactile communication. This approach was based on several tactile sensory characteristics of human skin at different body parts, such as the head and neck, where location coordinates in the three-dimensional (3D) space were clearly mapped in the brain cortex, and gentle stimulations of vibrational touching with varied strengths were received instantly and precisely. For certain applications, such as playing cards or navigating walk paths for blinded people, we demonstrated specifically designed code lists with different patterns of tactile points in varied temporal sequences. By optimizing these codes, we achieved excellent efficiency and accuracy in our test experiments. As this method matched well with the natural habits of tactile sensory, it was easy to learn in a short training period. The results of the present work have offered a silent, efficient and accurate communication solution for visually impaired people or other users.
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Percepción del Tacto , Personas con Daño Visual , Dispositivos Electrónicos Vestibles , Humanos , Tacto , PielRESUMEN
We propose a conceptually simple, general framework and end-to-end approach to point cloud completion, entitled PCA-Net. This approach differs from the existing methods in that it does not require a "simple" network, such as multilayer perceptrons (MLPs), to generate a coarse point cloud and then a "complex" network, such as auto-encoders or transformers, to enhance local details. It can directly learn the mapping between missing and complete points, ensuring that the structure of the input missing point cloud remains unchanged while accurately predicting the complete points. This approach follows the minimalist design of U-Net. In the encoder, we encode the point clouds into point cloud blocks by iterative farthest point sampling (IFPS) and k-nearest neighbors and then extract the depth interaction features between the missing point cloud blocks by the attention mechanism. In the decoder, we introduce a new trilinear interpolation method to recover point cloud details, with the help of the coordinate space and feature space of low-resolution point clouds, and missing point cloud information. This paper also proposes a method to generate multi-view missing point cloud data using a 3D point cloud hidden point removal algorithm, so that each 3D point cloud model generates a missing point cloud through eight uniformly distributed camera poses. Experiments validate the effectiveness and superiority of PCA-Net in several challenging point cloud completion tasks, and PCA-Net also shows great versatility and robustness in real-world missing point cloud completion.
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Algoritmos , Redes Neurales de la Computación , Análisis por Conglomerados , Suministros de Energía Eléctrica , Proyectos de InvestigaciónRESUMEN
Temperature is a significant factor in determining and characterizing cellular metabolism and other biochemical activities. In this study, we provide a brief overview of two important technologies used to monitor the local temperatures of individual living cells: fluorescence nano-thermometry and an array of micro-/nano-sized thin-film thermocouples. We explain some key technical issues that must be addressed and optimised for further practical applications, such as in cell biology, drug selection, and novel antitumor therapy. We also offer a method for combining them into a hybrid measuring system.
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Hipertermia Inducida , Termometría , Hipertermia Inducida/métodos , Temperatura , Termómetros , Termometría/métodosRESUMEN
Rootstock grafting is an important method to improve the yield and quality of seedlings. Pumpkin is the rootstock of watermelon, melon, and cucumber, and the root phenotype of rootstock is an important reference for breeding. At present, the root phenotype is mainly measured by scanners, with which it is difficult to achieve non-destructive and in situ measurements. In this work, we propose a method for non-destructive measurement of the root phenotype on the surface layer of the root ball of pumpkin rootstock plug seedlings and an accurate estimation of the surface area, length, and volume of total root using an AZURE KINECT sensor. Firstly, the KINECT is used to capture four-view color and depth images of the root surface, and then multi-view images are spliced to obtain a complete image of the root surface. After preprocessing of the images, we extract the roots from the root ball. For root phenotype measurements, the surface areas of the surface roots and root ball are calculated, followed by calculating root encapsulation. Next, the non-overlapping roots in the surface root image are extracted, and the ratio of the surface area to the skeleton length is used as the average diameter of total root. Based on the high correlation between the surface area of surface root and the surface area of total root, a linear fitting model is established to estimate the surface area, length, and volume of total root. The experiment ultimately showed that the measurement error for the average diameter of total root is less than 30 µm, and consistency with the scanner is higher than 93.3%. The accuracy of the surface area of total root estimation was found to be more than 88.1%, and the accuracy of the root length of total root estimation was observed to be greater than 87.2%. The method proposed in this paper offers similar accuracy to a scanner, which meets the needs of non-destructive root phenotype research. This method is expected to replace root scanners for high-throughput phenotypic measurements and provides a new avenue for root phenotype measurements of pumpkin rootstocks. This technology will provide key basic data for evaluating the root growth of pumpkin rootstocks.
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No genome-wide identification and expression analysis have been performed on the heat shock protein 70 (Hsp70) gene family, which is essential to key cellular processes and responses to environmental change, in decapods. In the present study, we identified nine members of the Hsp70 gene family within the genome of swimming crab (Portunus trituberculatus) and provided insights into their response to long-term low-salinity stress. Results demonstrated that gene structure and motifs are conserved among members of this gene family in P. trituberculatus. Under low-salinity stress, the expression of this gene family in the gill of P. trituberculatus showed that hsc70l.2 was significantly upregulated, hyou1 was significantly downregulated. The hsc70l.4 was not expressed. Furthermore, selection test on duplicated genes showed a negative selection on hsc70l.1, hsc70l.2, hsc70l.3, and hsc70l.4, suggesting functional redundancy. This may be the first study that systematically identified and analyzed the Hsp70 gene family in decapods. These results can provide fundamental data for the biological research of P. trituberculatus and enhance understanding of the biological function of Hsp70 in crustaceans adapting to salinity changes.
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Braquiuros , Animales , Braquiuros/metabolismo , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Salinidad , Estrés Salino , NataciónRESUMEN
A transparent and penetrable cranial window is essential for neuroimaging, transcranial injection and comprehensive understanding of cortical functions. For these applications, cranial windows made from glass coverslip, polydimethylsiloxane (PDMS), polymethylmethacrylate, crystal and silicone hydrogel have offered remarkable convenience. However, there is a lack of high-strength, high-transparency, penetrable cranial window with clinical application potential. We engineer high-strength hybrid Titanium-PDMS (Ti-PDMS) cranial windows, which allow large transparent area for in vivo two-photon imaging, and provide a soft window for transcranial injection. Laser scanning and 3D printing techniques are used to match the hybrid cranial window to different skull morphology. A multi-cycle degassing pouring process ensures a good combination of PDMS and Ti frame. Ti-PDMS cranial windows have a high fracture strength matching human skull bone, excellent light transmittance up to 94.4%, and refractive index close to biological tissue. Ti-PDMS cranial windows show excellent bio-compatibility during 21-week implantation in mice. Dye injection shows that the PDMS window has a "self-sealing" to keep liquid from leaking out. Two-photon imaging for brain tissues could be achieved up to 450 µm in z-depth. As a novel brain-computer-interface, this Ti-PDMS device offers an alternative choice for in vivo drug delivery, optical experiments, ultrasonic treatment and electrophysiology recording.
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Cráneo , Titanio , Animales , Ratones , Neuroimagen/métodos , Fotones , Impresión Tridimensional/instrumentación , Cráneo/diagnóstico por imagenRESUMEN
BACKGROUND: A national standardized emergency medicine (EM) curriculum for medical students, including specific competencies in procedural skills, are absent in many countries. The development of an intensive simulating training program in EM, based on a tight schedule, is anticipated to enhance the competency of medical students. METHODS: A 3-day intensive EM training program, consisting of four procedural skills and 8-hour case-based learning (CBL), was developed by experienced physicians from the EM department in Peking Union Medical College Hospital (PUMCH). Medical students from Peking Union Medical College (PUMC) and Tsinghua University (THU) participated in the training. Three written tests were cautiously designed to examine the short-term (immediately after the program) and long-term (6 months after the program) efficacy of the training. After completion of the training program, an online personal appraisal questionnaire was distributed to the students on WeChat (a mobile messaging App commonly used in China) to achieve anonymous self-evaluation. RESULTS: Ninety-seven out of 101 students completed the intensive training and took all required tests. There was a significant increase in the average score after the intensive simulating training program (pre-training 13.84 vs. 15.57 post-training, P<0.001). Compared with the pre-training test, 63 (64.9%) students made progress. There was no significant difference in scores between the tests taken immediately after the program and 6 months later (15.57±2.22 vs. 15.38±2.37, P=0.157). Students rated a higher score in all diseases and procedural skills, and felt that their learning was fruitful. CONCLUSIONS: The introduction of a standardized intensive training program in EM focusing on key competencies can improve clinical confidence, knowledge, and skills of medical students toward the specialty. In addition, having such a program can also enhance student's interest in EM as a career choice which may enhance recruitment into the specialty and workplace planning.
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Monitoring the thermal responses of individual cells to external stimuli is essential for studies of cell metabolism, organelle function, and drug screening. Fluorescent temperature probes are usually employed to measure the temperatures of individual cells; however, they have some unavoidable problems, such as, poor stability caused by their sensitivity to the chemical composition of the solution and the limitation in their measurement time due to the short fluorescence lifetime. Here, we demonstrate a stable, non-interventional, and high-precision temperature-measurement chip that can monitor the temperature fluctuations of individual cells subject to external stimuli and over a normal cell life cycle as long as several days. To improve the temperature resolution, we designed temperature sensors made of Pd-Cr thin-film thermocouples, a freestanding Si3N4 platform, and a dual-temperature control system. Our experimental results confirm the feasibility of using this cellular temperature-measurement chip to detect local temperature fluctuations of individual cells that are 0.3-1.5 K higher than the ambient temperature for HeLa cells in different proliferation cycles. In the future, we plan to integrate this chip with other single-cell technologies and apply it to research related to cellular heat-stress response.
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Técnicas Biosensibles , Colorantes Fluorescentes , Análisis de la Célula Individual , Temperatura , Células HeLa , HumanosRESUMEN
Flatheads are valuable commercial fish species endemic to the Indo-West Pacific. Due to their economic value and unique biological traits, such as metamorphosis and camouflage, they serve as ideal marine organisms for studies on demersal adaptation and evolution. The brown-spotted flathead (Platycephalus sp.1) is the most widely distributed in the northwestern Pacific. Despite the lack of a valid scientific name, it has been long recognized and exploited in the marine fisheries of China, Japan, and Korea. In the current study, we applied Illumina, PacBio, and Hi-C sequencing to assemble a chromosome-scale genome for this species. The assembled genome was 660.63 Mb long with a scaffold N50 of 28.65 Mb and 100% of the contigs were anchored onto 24 chromosomes. We predicted 22 743 protein-coding genes, 94.8% of which were functionally annotated. Comparative genomic analyses suggested that Platycephalus sp.1 diverged from its common ancestor with Gasterosteus aculeatus ~88.4 million years ago. The expanded gene families were significantly enriched in immune, biosynthetic, and metabolic pathways. Furthermore, three shared Gene Ontology terms and 377 common positively selected genes were identified between flathead and flatfish species, suggesting that these genes may contribute to demersal adaptation in flatheads. The assembled genomic data provide a valuable molecular resource for further research on the biological and adaptive evolution of flathead species.
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Adaptación Fisiológica/genética , Cromosomas/genética , Peces/genética , Genoma , Genómica/métodos , Animales , Océano Pacífico , FilogeniaRESUMEN
In this study, we used whole genome sequencing to obtain the complete mitochondrial genome of Hemitripterus villosus. This mitochondrial genome, consisting of 17,449 base pairs (bp), contains 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs and 2 noncoding control regions (control region and origin of light-strand replication) as those found in other vertebrates. Control region, of 1799 bp in length, is located between tRNAPro and tRNAPhe. We identified short tandem repeat sequences in the control region, which contributed largely to the relatively long mitogenome. The complete mitogenome data provides useful genetic markers for the studies on the molecular identification, phylogenetic analysis and conservation genetics.