anomaly

异常
  • 文章类型: Journal Article
    为了帮助放射科医生检查越来越多的计算机断层扫描(CT)扫描,自动异常检测是医学影像研究的热点。放射科医生必须通过搜索与正常健康解剖结构的任何偏差来分析CT扫描。我们提出了一种检测大脑轴向2DCT切片图像异常的方法。尽管已经进行了许多关于检测大脑磁共振图像异常的研究,CT扫描的工作很少,由于必须由所使用的模型表示的图像对比度低,因此更难以检测到异常。
    我们在第一步中使用生成对抗网络(GAN)来学习正常的大脑解剖结构,并比较两种图像重建方法:在第二步中训练编码器,并在推理过程中使用迭代优化。然后,我们分析与原始扫描的差异,以检测和定位大脑中的异常。
    我们的方法可以重建具有良好图像对比度的健康解剖结构,用于脑部CT扫描。我们在出血测试数据上获得的中位Dice评分为0.71,在测试集上获得的中位Dice评分为0.43,其他肿瘤图像来自公开可用的数据源。我们还将我们的模型与最先进的自动编码器和扩散模型进行比较,并获得定性更准确的重建。
    在训练期间没有定义异常,我们使用基于GAN的网络来学习用于脑部CT扫描的健康解剖学.值得注意的是,我们的方法不仅限于出血和肿瘤的定位,因此可用于检测结构解剖变化和其他病变.
    UNASSIGNED: To help radiologists examine the growing number of computed tomography (CT) scans, automatic anomaly detection is an ongoing focus of medical imaging research. Radiologists must analyze a CT scan by searching for any deviation from normal healthy anatomy. We propose an approach to detecting abnormalities in axial 2D CT slice images of the brain. Although much research has been done on detecting abnormalities in magnetic resonance images of the brain, there is little work on CT scans, where abnormalities are more difficult to detect due to the low image contrast that must be represented by the model used.
    UNASSIGNED: We use a generative adversarial network (GAN) to learn normal brain anatomy in the first step and compare two approaches to image reconstruction: training an encoder in the second step and using iterative optimization during inference. Then, we analyze the differences from the original scan to detect and localize anomalies in the brain.
    UNASSIGNED: Our approach can reconstruct healthy anatomy with good image contrast for brain CT scans. We obtain median Dice scores of 0.71 on our hemorrhage test data and 0.43 on our test set with additional tumor images from publicly available data sources. We also compare our models to a state-of-the-art autoencoder and a diffusion model and obtain qualitatively more accurate reconstructions.
    UNASSIGNED: Without defining anomalies during training, a GAN-based network was used to learn healthy anatomy for brain CT scans. Notably, our approach is not limited to the localization of hemorrhages and tumors and could thus be used to detect structural anatomical changes and other lesions.
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  • 文章类型: Journal Article
    背景在这项研究中,我们的目的是报告单中心腹腔镜小儿泌尿外科手术的经验.我们旨在确定各种泌尿外科和泌尿生殖系统腹腔镜手术的可行性以及提高手术成功率的技巧。方法回顾性分析2018年6月至2023年2月在我们的诊所接受腹腔镜泌尿系统和/或泌尿生殖系统手术以诊断和治疗目的的98例患者的数据。所有手术均由同一手术团队进行。腹腔镜手术包括睾丸固定术,性腺切除术,阴道成形术,子宫切除术,肾盂成形术,肾切除术/肾部分切除术,输尿管膀胱造口术,膀胱憩室切除术,肾囊肿切除术,输尿管近端结石清除术,卵巢切除术,卵巢扭曲,oophoroopexy,和用于诊断目的的淋巴结切除。患者的手术计划是基于小儿肾脏病的决定,儿科内分泌学,儿科肿瘤科和多学科理事会。患者的人口统计学特征,手术适应症,术中数据,以及术后病理诊断和并发症,被记录下来。所有患者均行腹膜入路。手术持续时间从麻醉记录中获得,并定义为从手术切口开始到皮肤切口闭合的时间。结果患者,男性54人,女性44人。中位年龄为7.8岁。在我们的患者中观察到除Clavien-Dindo分类的1级以外的并发症。随着对不同类型的手术进行分析,估计了平均手术时间.结论在小儿泌尿外科中,腹腔镜手术应由经验丰富的外科医师进行。在准备腹腔镜手术以最大程度地减少技术和人体工程学问题时,考虑儿科患者大小的差异至关重要。我们相信每个手术都有其特定的技巧,这些应该是腹腔镜培训的一部分。此外,开发和分享这些信息对儿科泌尿科医师非常有用。
    Background In this study, we aim to report our single-center experience with laparoscopic pediatric urological surgeries. We aim to determine the feasibility of various urological and urogenital laparoscopic procedures and the tricks that increase surgical success. Methodology Data from 98 patients who underwent laparoscopic urological and/or urogenital procedures for diagnostic and therapeutic purposes in our clinic between June 2018 and February 2023 were retrospectively analyzed. All surgeries were performed by the same surgical team. Laparoscopic procedures included orchidopexy, gonadectomy, vaginoplasty, hysterectomy, pyeloplasty, nephrectomy/partial nephrectomy, ureteroneocystostomy, bladder diverticulum excision, renal cyst excision, proximal ureter stone removal, oophorectomy, ovarian detorsion, oophoropexy, and lymph node excision for diagnostic purposes. The surgical planning of the patients was based on the decisions of the pediatric nephrology, pediatric endocrinology, and pediatric oncology departments and the multidisciplinary council. Demographic characteristics of the patients, surgical indications, and intraoperative data, as well as postoperative pathological diagnoses and complications, were recorded. All patients underwent a transperitoneal approach. The duration of the operation was obtained from anesthesia records and defined as the time from the beginning of the surgical incision to the closure of the skin incision. Results Of the patients, 54 were males and 44 were females. The median age was 7.8 years. No complications other than grade 1 according to the Clavien-Dindo classification were observed in our patients. As different types of surgeries were analyzed, the mean operative duration was estimated. Conclusions The laparoscopic method should be performed by surgeons experienced in advanced surgeries in pediatric urology. It is critical to consider the difference in the size of pediatric patients in preparation for laparoscopic surgery to minimize technical and ergonomic problems. We believe that each surgery has its specific tricks and that these should be a part of laparoscopy training. Moreover, developing and sharing this information would be very useful for pediatric urologists.
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  • 文章类型: Case Reports
    背景:交叉融合肾异位(CFRE)是一种常见的先天性异常,其中一个肾脏异常位于中线的另一侧,经常与另一个肾脏融合。然而,单个输尿管引流交叉融合肾异位是罕见的。
    方法:这里,我们报告了一例有结石病史的46岁尼泊尔男性患者的交叉融合性肾异位伴单个输尿管。计算机断层扫描显示左肾位于右侧并与右肾融合。两个肾脏的肾盂融合,和一个输尿管,位于右侧,将两个肾脏排入膀胱。建议患者定期随访。
    结论:单输尿管交叉融合肾异位是一种罕见的肾脏异常。无症状患者通常可以保守治疗。建议定期随访以监测肾功能,微积分形成,感染,和恶性变化。
    BACKGROUND: Crossed fused renal ectopia (CFRE) is a common congenital anomaly where one kidney is positioned abnormally on the opposite side of the midline, often fused with the other kidney. However, single ureter draining crossed fused renal ectopia is a rare occurrence.
    METHODS: Here, we report a case of crossed fused renal ectopia with a single ureter in a 46-year-old Nepali male who presented with history of lithuria. Computed tomography revealed that the left kidney was situated on the right side and fused with the right kidney. The renal pelvises of both kidneys were fused, and a single ureter, located on the right side, was draining both kidneys into the bladder. The patient was advised to have regular follow-ups.
    CONCLUSIONS: Crossed fused renal ectopia with a single ureter represents a rare renal anomaly. Asymptomatic patients can typically be managed conservatively. Regular follow-up is recommended to monitor renal function, calculus formation, infections, and malignant changes.
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  • 文章类型: Journal Article
    这项研究的目的是使用科学哲学的历史方法和核心原理来解释为什么在乳酸性酸中毒构造的发展中犯了错误。在更广泛的范围内,这项研究解释了什么是科学,为什么一些科学家尽管有良好的意图,经常弄错,以及为什么需要这么长时间(几十年)来纠正这些错误。科学是一种人类行为,包括基于正确应用先验知识来识别问题,开发一种最佳解决或测试问题的方法,完成这些方法以获得结果,然后对结果进行正确的解释。如果这些步骤正确完成,则结果可能正确的可能性会增加(不能保证)。托马斯·库恩提出,你可以从科学的表现来理解什么是科学,从他的论文中,他揭示了一种功能失调的科学形式,他称之为“正常”(由于其存在的优势)。相反,卡尔·波普尔坚持认为,“正常”科学的实践揭示了许多缺陷,这些缺陷偏离了科学的基本原理,科学。总的来说,证据表明,在运动医学和健康科学中,和所有学科一样,科学中的错误比你想象的更频繁。迫切需要改进我们如何教育和培训科学家,以防止对“正常”科学的追求及其对人类的危害。
    The purpose of this research was to use a historical method and core principles from scientific philosophy to explain why mistakes were made in the development of the lactic acidosis construct. On a broader scope, this research explains what science is, why some scientists despite good intention, often get it wrong, and why it takes so long (decades) to correct these errors. Science is a human behaviour that consists of the identification of a problem based on the correct application of prior knowledge, the development of a method to best resolve or test the problem, completion of these methods to acquire results, and then a correct interpretation of the results. If these steps are done correctly there is an increased probability (no guarantee) that the outcome is likely to be correct. Thomas Kuhn proposed that you can understand what science is from how it has been performed, and from his essays he revealed a very dysfunctional form of science that he called \'normal\' (due the preponderance of its presence) science. Conversely, Karl Popper was adamant that the practice of \'normal\' science revealed numerous flaws that deviate from fundamental principles that makes science, science. Collectively, the evidence reveals that within the sports medicine and health sciences, as with all disciplines, errors in science are more frequent than you might expect. There is an urgent need to improve how we educate and train scientists to prevent the pursuit of \'normal\' science and the harm it imparts on humanity.
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  • 文章类型: Journal Article
    关于横截面股票收益可预测性的文献已经记录了超过450个因素。我们从机构投资者的角度出发,通过关注与基于因子的投资策略的实用性相关的证据,来浏览这个因子动物园。建立健全的理论基础是确定“真实”因素的关键,我们强调需要认识到数据挖掘问题,这些问题可能会对许多因素的相关性产生怀疑。从实际投资的角度来看,学者记录的许多因素证据可能比真实更明显。许多因素的表现取决于将小型和微型股票纳入学术研究,尽管由于流动性不足和交易成本,此类股票可能会被排除在实际投资领域之外。然而,股票和其他资产类别中出现了一套简约的因素,包括货币,固定收入,和商品。这些因素可以作为基于因素的投资组合构建的有意义的成分。
    The literature on cross-sectional stock return predictability has documented over 450 factors. We take the perspective of an institutional investor and navigate this zoo of factors by focusing on the evidence relevant to the practicalities of factor-based investment strategies. Establishing a sound theoretical rationale is key to identifying \"true\" factors, and we emphasize the need to recognize data-mining concerns that may cast doubt on the relevance of many factors. From a practical investment perspective, much of the factor evidence documented by academics may be more apparent than real. The performance of many factors is dependent on the inclusion of small- and micro-cap stocks in academic studies, although such stocks would likely be excluded from the real investment universe due to illiquidity and transaction costs. Nevertheless, a parsimonious set of factors emerges in equities and other asset classes, including currencies, fixed income, and commodities. These factors can serve as meaningful ingredients to factor-based portfolio construction.
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  • 文章类型: Journal Article
    随着它的指数增长,物联网(IoT)产生了前所未有的连接和数据水平。异常检测是一种安全功能,用于识别系统行为偏离预期规范的实例,便于及时识别和解决异常情况。当AI和物联网结合在一起时,异常检测变得更加有效,提高可靠性,功效,物联网系统的完整性。基于AI的异常检测系统能够识别物联网环境中的各种威胁,包括蛮力,缓冲区溢出,注射,重播攻击,DDoS攻击,SQL注入,和后门漏洞。智能入侵检测系统(IDS)在物联网设备中势在必行,这有助于检测网络中的异常或入侵,随着物联网在多个行业中的应用越来越多,但拥有庞大的攻击面,为攻击者提供了更多的切入点。本研究回顾了使用机器学习和深度学习在物联网基础设施中进行异常检测的文献。本文讨论了在物联网系统中检测入侵和异常的挑战,越来越多的攻击。它回顾了物联网网络机器学习和深度学习异常检测方案的最新工作。总结现有文献。从这次调查来看,结论是,需要通过使用不同的数据集来进一步开发当前的系统,实时测试,并使系统可扩展。
    With its exponential growth, the Internet of Things (IoT) has produced unprecedented levels of connectivity and data. Anomaly detection is a security feature that identifies instances in which system behavior deviates from the expected norm, facilitating the prompt identification and resolution of anomalies. When AI and the IoT are combined, anomaly detection becomes more effective, enhancing the reliability, efficacy, and integrity of IoT systems. AI-based anomaly detection systems are capable of identifying a wide range of threats in IoT environments, including brute force, buffer overflow, injection, replay attacks, DDoS assault, SQL injection, and back-door exploits. Intelligent Intrusion Detection Systems (IDSs) are imperative in IoT devices, which help detect anomalies or intrusions in a network, as the IoT is increasingly employed in several industries but possesses a large attack surface which presents more entry points for attackers. This study reviews the literature on anomaly detection in IoT infrastructure using machine learning and deep learning. This paper discusses the challenges in detecting intrusions and anomalies in IoT systems, highlighting the increasing number of attacks. It reviews recent work on machine learning and deep-learning anomaly detection schemes for IoT networks, summarizing the available literature. From this survey, it is concluded that further development of current systems is needed by using varied datasets, real-time testing, and making the systems scalable.
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  • 文章类型: Case Reports
    我们遇到了一个结肠癌病例,其中结肠中动脉(MCA)起源于脾动脉(SA)。
    一名妇女因横结肠癌被转诊到我们医院。三维计算机断层扫描(3D-CT)血管造影显示异常的MCA起源于SA,而不是典型的肠系膜上动脉(SMA)。行腹腔镜左半结肠切除术并D3淋巴结清扫术。从尾部视图解剖SMA周围的淋巴结,确认没有典型的MCA。胰腺下方发现了一个异常的SA起源MCA,在那里被剪接和结扎;随后,实现了肠系膜全切除。
    由于横结肠癌的D3淋巴结清扫在技术上很困难,3D-CT血管造影可用于术前识别血管异常,从而避免术中损伤。这是与SA起源的MCA异常相关的腹腔镜结肠切除术的首例报告。
    UNASSIGNED: We encountered a colon cancer case with a very rare anomaly of the middle colic artery (MCA) originating from the splenic artery (SA).
    UNASSIGNED: A woman was referred to our hospital for transverse colon cancer. Three-dimensional computed tomography (3D-CT) angiography showed an anomalous MCA originating from the SA rather than from the superior mesenteric artery (SMA) as is typical. Laparoscopic left hemicolectomy with D3 lymph node dissection was performed. The lymph nodes around the SMA were dissected from the caudal view, confirming the absence of a typical MCA. An anomalous SA-originating MCA was identified just below the pancreas, where it was clipped and ligated; subsequently, total mesenteric excision was achieved.
    UNASSIGNED: As D3 lymph node dissection for transverse colon cancer is technically difficult, 3D-CT angiography is useful for identifying vascular anomalies preoperatively, thereby avoiding intraoperative injury. This is the first case report of laparoscopic colectomy associated with a SA-originating MCA anomaly.
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  • 文章类型: Journal Article
    自2015年以来,有关机器人系统异常检测的文章有所增加,反映了其在提高越来越多地使用的自主机器人的鲁棒性和可靠性方面的重要性。本文研究了有关自主机器人任务(ARM)异常检测的文献。它揭示了异常和并置与故障检测的不同观点。达成共识,我们推断了对异常的统一理解,这些异常包含了在ARM中观察到的各种特征,并提出了在空间上对异常的分类,temporal,和基于其基本特征的时空要素。Further,本文讨论了拟议的统一理解和分类在ARM中的意义,并提供了未来的方向。我们设想围绕术语异常的特定用法进行研究,以及它们的检测方法可以促进和加速ARM通用异常检测系统的研究和开发。
    Since 2015, there has been an increase in articles on anomaly detection in robotic systems, reflecting its growing importance in improving the robustness and reliability of the increasingly utilized autonomous robots. This review paper investigates the literature on the detection of anomalies in Autonomous Robotic Missions (ARMs). It reveals different perspectives on anomaly and juxtaposition to fault detection. To reach a consensus, we infer a unified understanding of anomalies that encapsulate their various characteristics observed in ARMs and propose a classification of anomalies in terms of spatial, temporal, and spatiotemporal elements based on their fundamental features. Further, the paper discusses the implications of the proposed unified understanding and classification in ARMs and provides future directions. We envisage a study surrounding the specific use of the term anomaly, and methods for their detection could contribute to and accelerate the research and development of a universal anomaly detection system for ARMs.
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  • 文章类型: Journal Article
    甲烷氧化细菌(MOB)长期以来一直被认为是油气勘探的重要生物指标。然而,由于它们的生理和生态多样性,MOB在不同栖息地的分布差异很大,使用常规方法真实反映油气藏上方土壤中活跃MOB的丰度具有挑战性。这里,我们选择了中国西南四川盆地的普光气田作为模型系统,使用独立于培养的分子技术研究了甲烷氧化菌的生态特征。最初,通过比较定量PCR(qPCR)确定的pmoA基因的丰度,气井和非气井土壤之间没有发现显着差异,表明总MOB的丰度不一定反映下层气藏的分布。13C-DNA稳定同位素探测(DNA-SIP)与高通量测序(HTS)相结合,进一步揭示了II型甲烷营养甲基球菌是非气田土壤中绝对主要的活性MOB,而在地质尺度适应痕量和连续甲烷供应后,在气藏的表层土壤中,由Methylocystis腾出的生态位逐渐被I型RPC-2(稻田簇2)和Methylosarcina填充。然后将RPC-2和Methylosarcina的相对丰度之和用作普光气田的特定生物指数(BI)。基于BI值的微生物异常分布图显示,异常带与地质和地球物理数据高度一致,和已知的钻井结果。因此,活性而非总甲烷营养生物成功地反映了底层活性烃系统的微渗漏强度,可作为确定储层存在和分布的重要定量指标。我们的结果表明,分子微生物技术是油气勘探的有力工具。
    Methane-oxidizing bacteria (MOB) have long been recognized as an important bioindicator for oil and gas exploration. However, due to their physiological and ecological diversity, the distribution of MOB in different habitats varies widely, making it challenging to authentically reflect the abundance of active MOB in the soil above oil and gas reservoirs using conventional methods. Here, we selected the Puguang gas field of the Sichuan Basin in Southwest China as a model system to study the ecological characteristics of methanotrophs using culture-independent molecular techniques. Initially, by comparing the abundance of the pmoA genes determined by quantitative PCR (qPCR), no significant difference was found between gas well and non-gas well soils, indicating that the abundance of total MOB may not necessarily reflect the distribution of the underlying gas reservoirs. 13C-DNA stable isotope probing (DNA-SIP) in combination with high-throughput sequencing (HTS) furthermore revealed that type II methanotrophic Methylocystis was the absolutely predominant active MOB in the non-gas-field soils, whereas the niche vacated by Methylocystis was gradually filled with type I RPC-2 (rice paddy cluster-2) and Methylosarcina in the surface soils of gas reservoirs after geoscale acclimation to trace- and continuous-methane supply. The sum of the relative abundance of RPC-2 and Methylosarcina was then used as specific biotic index (BI) in the Puguang gas field. A microbial anomaly distribution map based on the BI values showed that the anomalous zones were highly consistent with geological and geophysical data, and known drilling results. Therefore, the active but not total methanotrophs successfully reflected the microseepage intensity of the underlying active hydrocarbon system, and can be used as an essential quantitative index to determine the existence and distribution of reservoirs. Our results suggest that molecular microbial techniques are powerful tools for oil and gas prospecting.
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  • 文章类型: Case Reports
    异位肝叶是一种罕见的异常,最常报告为孤立性肿块。在这里,我们报告一例尸检时发现多(两)异位肝叶。一名70多岁的日本男子死于与获得性免疫缺陷综合症(AIDS)相关的传染病。尸检显示偶然发现了两个1厘米的肿块,位于下腔静脉前方。两个肿块均由肝组织组成,内部微观结构类似肝门,由流出胆管和血管组成。流出胆管似乎与胆总管相连,但是流出血管的连接点不清楚。肝组织表现为中央静脉纤维性增厚和门静脉病变,包括门静脉区域的纤维化以及门静脉的狭窄和丢失。没有拥堵的证据,纤维化,胆汁淤滞,或者肿瘤。异位肝叶肝细胞癌的发病率高于正常肝脏,可能是由于异常的循环和胆汁排泄途径。患者还出现门静脉病变;这表明存在异常的循环动力学。
    The ectopic liver lobe is a rare anomaly and is most frequently reported as a solitary mass. Herein, we report a case of multiple (two) ectopic liver lobes detected at an autopsy. A Japanese man in his 70s died of an infectious disease associated with acquired immunodeficiency syndrome (AIDS). Autopsy revealed the incidental finding of two 1-cm masses, located anterior to the inferior vena cava. Both masses were composed of liver tissue and had internal microscopic structures resembling the porta hepatis, consisting of an outflow bile duct and blood vessels. The outflow bile duct appeared to be continuous with the common bile duct, but the connection point of the outflow vessel was unclear. The liver tissue showed fibrous thickening of the central veins and portal venopathy, including fibrosis in the portal area as well as narrowing and loss of the portal veins. There was no evidence of congestion, fibrosis, biliary stasis, or neoplasm. The incidence of hepatocellular carcinoma is higher in the ectopic liver lobe than in the proper liver, presumably due to the abnormal circulation and bile excretion pathways. The patient also presented with portal venopathy; this suggests the presence of abnormal circulatory dynamics.
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