Kliknij ten link, aby zobaczyć inne rodzaje publikacji na ten temat: LONG TAIL ISSUE.
Artykuły w czasopismach na temat „LONG TAIL ISSUE”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Sprawdź 50 najlepszych artykułów w czasopismach naukowych na temat „LONG TAIL ISSUE”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Przeglądaj artykuły w czasopismach z różnych dziedzin i twórz odpowiednie bibliografie.
1
Fenge, Lee-Ann, Kip Jones i Camilla Gibson. "Meaningful dissemination produces the “long tail” that engenders community impact". Qualitative Research Journal 18, nr 1 (5.02.2018): 45–54. http://dx.doi.org/10.1108/qrj-d-17-00037.
Pełny tekst źródłaStreszczenie:
Purpose Lack of understanding of the needs of older LGBT individuals is a global issue and their needs are often ignored by health and social care providers who adopt sexuality-blind approaches within their provision. As a result, public services can find it difficult to push the LGBT equalities agenda forward due to resistance to change and underlying discrimination. The aim of this paper is to discuss these issues. Design/methodology/approach This report considers how a body of participatory research concerning the needs and experiences of older LGBT people was used to create innovatory dissemination tools, which then engaged communities through public engagement to learn about the needs and experiences of older LGBT citizens. Good research has a “long tail” – (in statistics, “a large number of occurrences far from the ‘head’ or central part of the distribution”). The report considers how a film and a method deck of cards, presented to service providers in several workshops over time, offered opportunities to learn and critically reflect upon an informed practice. Findings Because of the on-going feedback from our workshops, the authors, in turn, learned the importance of having a champion within a community organisation to take forward the LGBT agenda. A report of one such outreach champion is included here. Originality/value Consideration is given to challenges involved in creating impact through research, and how participatory community processes may enhance impact to develop over time.
2
Qin, Jing. "A Survey of Long-Tail Item Recommendation Methods". Wireless Communications and Mobile Computing 2021 (29.11.2021): 1–14. http://dx.doi.org/10.1155/2021/7536316.
Pełny tekst źródłaStreszczenie:
Recommender systems represent a critical field of AI technology applications. The core function of a recommender system is to recommend items of interest to users, but if it is only user history-based (purchasing or browsing data), it can only recommend similar products to a user, which makes the user feel fatigued (creating so-called “Information Cocoons”). Besides, transaction data (purchasing or browsing data) in various fields usually follow Pareto distributions. Accordingly, 20% of products are purchased or viewed a greater number of times (short-head items), while the remaining 80% of products are purchased or viewed less frequently (long-tail items). Using the traditional recommendation method, considering only the accuracy of recommendations, the coverage rate is relatively low, and most of the recommended items are short-head items. The long-tail item recommendation method not only considers the recommendation of short-head items but also considers recommending more long-tail items to users, thus improving the coverage and diversity of the recommendation results. Long-tail item recommendation research has become a frontier issue in recommendation systems in recent years. While the current research paper is still scarce, there have been related research achievements in top-level conferences in the field of computers, such as VLDB and IJCAI. Due to the fact that there is no review literature in this field, to allow readers to better understand the research status of the long-tail item recommendation method, this paper summarizes the progress of the research on long-tail item recommendation methods (from clustering-based, which began in 2008, to deep learning-based methods, which began in 2020) and the future directions associated with this research.
3
Xu, Pengyu, Lin Xiao, Bing Liu, Sijin Lu, Liping Jing i Jian Yu. "Label-Specific Feature Augmentation for Long-Tailed Multi-Label Text Classification". Proceedings of the AAAI Conference on Artificial Intelligence 37, nr 9 (26.06.2023): 10602–10. http://dx.doi.org/10.1609/aaai.v37i9.26259.
Pełny tekst źródłaStreszczenie:
Multi-label text classification (MLTC) involves tagging a document with its most relevant subset of labels from a label set. In real applications, labels usually follow a long-tailed distribution, where most labels (called as tail-label) only contain a small number of documents and limit the performance of MLTC. To facilitate this low-resource problem, researchers introduced a simple but effective strategy, data augmentation (DA). However, most existing DA approaches struggle in multi-label settings. The main reason is that the augmented documents for one label may inevitably influence the other co-occurring labels and further exaggerate the long-tailed problem. To mitigate this issue, we propose a new pair-level augmentation framework for MLTC, called Label-Specific Feature Augmentation (LSFA), which merely augments positive feature-label pairs for the tail-labels. LSFA contains two main parts. The first is for label-specific document representation learning in the high-level latent space, the second is for augmenting tail-label features in latent space by transferring the documents second-order statistics (intra-class semantic variations) from head labels to tail labels. At last, we design a new loss function for adjusting classifiers based on augmented datasets. The whole learning procedure can be effectively trained. Comprehensive experiments on benchmark datasets have shown that the proposed LSFA outperforms the state-of-the-art counterparts.
4
He, Jiangpeng, Luotao Lin, Heather A. Eicher-Miller i Fengqing Zhu. "Long-Tailed Food Classification". Nutrients 15, nr 12 (15.06.2023): 2751. http://dx.doi.org/10.3390/nu15122751.
Pełny tekst źródłaStreszczenie:
Food classification serves as the basic step of image-based dietary assessment to predict the types of foods in each input image. However, foods in real-world scenarios are typically long-tail distributed, where a small number of food types are consumed more frequently than others, which causes a severe class imbalance issue and hinders the overall performance. In addition, none of the existing long-tailed classification methods focus on food data, which can be more challenging due to the inter-class similarity and intra-class diversity between food images. In this work, two new benchmark datasets for long-tailed food classification are introduced, including Food101-LT and VFN-LT, where the number of samples in VFN-LT exhibits real-world long-tailed food distribution. Then, a novel two-phase framework is proposed to address the problem of class imbalance by (1) undersampling the head classes to remove redundant samples along with maintaining the learned information through knowledge distillation and (2) oversampling the tail classes by performing visually aware data augmentation. By comparing our method with existing state-of-the-art long-tailed classification methods, we show the effectiveness of the proposed framework, which obtains the best performance on both Food101-LT and VFN-LT datasets. The results demonstrate the potential to apply the proposed method to related real-life applications.
5
Fagette, S., M. Lo, C. Gharib i G. Gauquelin. "Cardiovascular variability and baroreceptor reflex sensitivity over a 14-day tail suspension in rats". Journal of Applied Physiology 78, nr 2 (1.02.1995): 717–24. http://dx.doi.org/10.1152/jappl.1995.78.2.717.
Pełny tekst źródłaStreszczenie:
To verify whether a long-term weightlessness simulation was associated with development of cardiovascular deconditioning, male Wistar rats were tail suspended for 13 days and then removed for a 24-h recovery. Blood pressure (BP) and heart rate (HR) responses, their spectral properties, and the pharmacologically tested baroreceptor reflex sensitivity were studied throughout the suspension period and after removal from the tail suspension device. BP, HR, and their variability were not altered over the experimental period, and there were no indications of orthostatic intolerance on release from head-down suspension. Spectral properties of BP and HR were unchanged during the experiment, and tail suspension did not induce modifications in the baroreceptor reflex sensitivity. These results taken together suggest that cardiovascular deconditioning may not be developed even after long-term hindlimb suspension in rats, in contrast to humans exposed to actual or simulated weightlessness. Our results raise issue with the use of tail-suspended rats as a valid model for the study of alterations in cardiovascular function induced by spaceflight in humans.
6
Crudden, Caitrin, i Leonard Girnita. "The tale of a tail: The secret behind IGF-1R’s oncogenic power". Science Signaling 13, nr 633 (26.05.2020): eabb7887. http://dx.doi.org/10.1126/scisignal.abb7887.
Pełny tekst źródłaStreszczenie:
The C-terminal tail of insulin-like growth factor 1 receptor (IGF-1R) has long been appreciated to drive much of this receptor’s oncogenic power. In this issue of Science Signaling, Rieger et al. have shown that Tyr1250 and Tyr1251 of IGF-1R are autophosphorylated in a cell adhesion–dependent manner, uncovering a previously unknown plasma membrane–Golgi trafficking route for IGF-1R in migratory cells, an integral part of the malignant phenotype.
7
Chen, Xiaohua, Yucan Zhou, Dayan Wu, Wanqian Zhang, Yu Zhou, Bo Li i Weiping Wang. "Imagine by Reasoning: A Reasoning-Based Implicit Semantic Data Augmentation for Long-Tailed Classification". Proceedings of the AAAI Conference on Artificial Intelligence 36, nr 1 (28.06.2022): 356–64. http://dx.doi.org/10.1609/aaai.v36i1.19912.
Pełny tekst źródłaStreszczenie:
Real-world data often follows a long-tailed distribution, which makes the performance of existing classification algorithms degrade heavily. A key issue is that the samples in tail categories fail to depict their intra-class diversity. Humans can imagine a sample in new poses, scenes and view angles with their prior knowledge even if it is the first time to see this category. Inspired by this, we propose a novel reasoning-based implicit semantic data augmentation method to borrow transformation directions from other classes. Since the covariance matrix of each category represents the feature transformation directions, we can sample new directions from similar categories to generate definitely different instances. Specifically, the long-tailed distributed data is first adopted to train a backbone and a classifier. Then, a covariance matrix for each category is estimated, and a knowledge graph is constructed to store the relations of any two categories. Finally, tail samples are adaptively enhanced via propagating information from all the similar categories in the knowledge graph. Experimental results on CIFAR-LT-100, ImageNet-LT, and iNaturalist 2018 have demonstrated the effectiveness of our proposed method compared with the state-of-the-art methods.
8
Gao, Zong Jun, Jia Guo Ren, Jia Liang Li, Hong Cao, Qian Qian Wu, Zhao Xiang Zhang i Hai Hui Ma. "The Comprehensive Test for Geothermal Tail-Water Disposal". Advanced Materials Research 403-408 (listopad 2011): 4522–27. http://dx.doi.org/10.4028/www.scientific.net/amr.403-408.4522.
Pełny tekst źródłaStreszczenie:
Geothermal reservoirs and groundwater resources in layered porous media in large sedimentary basins have enormous exploitation potential because of their extensive distribution, great quantity, and feasible temperatures and drilling depths. The discharge of geothermal wastewater (i.e. tail-water) on the surface is a serious environmental issue because of its high salinity content, so the Bureau of Geology Exploration and Mineral Resources Exploitation in Shandong Province, China called for the study of the disposal technique of the geothermal tail-water. The disposal test process is as follows: take the waste of geothermal water to make physics-chemistry preparative disposal; filtration with manganese-sand set and/or double-medium equipment; filtration with ion exchange resins; nanofiltration membrane separation; and reverse osmosis separation. After separation, the cheap, clean water can be used as a material for chemical plants. However, in the case of deeply embedded geothermal groundwater resources, connate water(buried water), or bad recharge conditions, must be dried up for a long time exploitation, causing ground depression. Therefore, it is concluded that systems utilizing reinjection, i.e. closed-circuit cycle mode injection, in sandstone reservoirs are ideal for the realization of sustainable exploitation of the geothermal groundwater resources with favorable environmental conditions on the surface.
9
Hambrick, Donald C. "The fattest of the fat cats: observations on Aguinis and colleagues’ findings on CEO pay". Management Research: Journal of the Iberoamerican Academy of Management 16, nr 1 (9.04.2018): 31–37. http://dx.doi.org/10.1108/mrjiam-04-2017-0741.
Pełny tekst źródłaStreszczenie:
Purpose This paper aims to elaborate upon the work of Aguinis and colleagues (this issue), who showed that there is almost no overlap between the chief executive officers (CEOs; of American publicly traded corporations) who are in the upper tail of the CEO pay distribution and the firms that are in the upper tail of the performance distribution. Design/methodology/approach This paper is an essay/commentary regarding the merits and implications of the paper by Aguinis and colleagues. Findings Drawing upon prior work, the author proposes that CEOs’ tenure-long pay patterns are established – essentially baked-in or hardwired – when CEOs first get hired. For various reasons, some CEOs receive ultra-grand pay packages at the outset of their tenures, and nothing – including mediocre performance – brings about subsequent diminishment of those sweet terms. Research limitations/implications This paper sheds new light on the work by Aguinis and colleagues, in turn contributing new insights about the fairness (or lack thereof) of CEO pay determinations. Originality/value This paper integrates Aguinis and colleagues with prior works on CEO over- and underpayment.
10
Das, Chinmay, i Peter D. Olmsted. "The physics of stratum corneum lipid membranes". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, nr 2072 (28.07.2016): 20150126. http://dx.doi.org/10.1098/rsta.2015.0126.
Pełny tekst źródłaStreszczenie:
The stratum corneum (SC), the outermost layer of skin, comprises rigid corneocytes (keratin-filled dead cells) in a specialized lipid matrix. The continuous lipid matrix provides the main barrier against uncontrolled water loss and invasion of external pathogens. Unlike all other biological lipid membranes (such as intracellular organelles and plasma membranes), molecules in the SC lipid matrix show small hydrophilic groups and large variability in the length of the alkyl tails and in the numbers and positions of groups that are capable of forming hydrogen bonds. Molecular simulations provide a route for systematically probing the effects of each of these differences separately. In this article, we present the results from atomistic molecular dynamics of selected lipid bilayers and multi-layers to probe the effect of these polydispersities. We address the nature of the tail packing in the gel-like phase, the hydrogen bond network among head groups, the bending moduli expected for leaflets comprising SC lipids and the conformation of very long ceramide lipids in multi-bilayer lipid assemblies. This article is part of the themed issue ‘Soft interfacial materials: from fundamentals to formulation’.
11
Villon, Sébastien, Corina Iovan, Morgan Mangeas i Laurent Vigliola. "Confronting Deep-Learning and Biodiversity Challenges for Automatic Video-Monitoring of Marine Ecosystems". Sensors 22, nr 2 (10.01.2022): 497. http://dx.doi.org/10.3390/s22020497.
Pełny tekst źródłaStreszczenie:
With the availability of low-cost and efficient digital cameras, ecologists can now survey the world’s biodiversity through image sensors, especially in the previously rather inaccessible marine realm. However, the data rapidly accumulates, and ecologists face a data processing bottleneck. While computer vision has long been used as a tool to speed up image processing, it is only since the breakthrough of deep learning (DL) algorithms that the revolution in the automatic assessment of biodiversity by video recording can be considered. However, current applications of DL models to biodiversity monitoring do not consider some universal rules of biodiversity, especially rules on the distribution of species abundance, species rarity and ecosystem openness. Yet, these rules imply three issues for deep learning applications: the imbalance of long-tail datasets biases the training of DL models; scarce data greatly lessens the performances of DL models for classes with few data. Finally, the open-world issue implies that objects that are absent from the training dataset are incorrectly classified in the application dataset. Promising solutions to these issues are discussed, including data augmentation, data generation, cross-entropy modification, few-shot learning and open set recognition. At a time when biodiversity faces the immense challenges of climate change and the Anthropocene defaunation, stronger collaboration between computer scientists and ecologists is urgently needed to unlock the automatic monitoring of biodiversity.
12
Aoki, Takahiro, Makoto Shibata, Guilherme Violin, Shogo Higaki i Koji Yoshioka. "Detection of foaling using a tail-attached device with a thermistor and tri-axial accelerometer in pregnant mares". PLOS ONE 18, nr 6 (2.06.2023): e0286807. http://dx.doi.org/10.1371/journal.pone.0286807.
Pełny tekst źródłaStreszczenie:
It is desirable to attend to the mare at the time of foaling in order to assist fetal delivery and prevent complications. The early detection of the onset of labor is an important issue for the equine industry. The purpose of this study was to examine the applicability of a sensor for foaling detection using the data of surface temperature (ST), roll angle (rotation about the y-axis) and y-axis (long axis of the tail) acceleration which were collected from a multimodal device attached to the ventral tail base of the mare. The data were collected every 3 minutes in 17 pregnant mares. Roll angle differences from the reference values and the mare’s posture (standing or recumbent) confirmed by video were compared and associated. Cohen’s kappa coefficient was 0.99 when the threshold was set as ± 0.3 radian in roll angle differences. This result clearly showed that the sensor data can accurately distinguish between standing and recumbent postures. The hourly sensor data with a lower ST (LST < 35.5°C), a recumbent posture determined by the roll angle, and tail-raising (TR, decline of 200 mg or more from the reference value in y-axis acceleration) was significantly higher during the last hour prepartum than 2−120 hours before parturition (P < 0.01). The accuracy of foaling detection within one hour was verified using the following three indicators: LST; lying down (LD, change from standing to recumbent posture); and TR. When LST, LD and TR were individually examined, even though all indicators showed that sensitivity was 100%, the precision was 13.1%, 8.1% and 2.8%, respectively. When the data were combined as LST+LD, LST+TR, LD+TR and LST+LD+TR, detection of foaling improved, with precisions of 100%, 32.1%, 56.7% and 100%, respectively. In conclusion, the tail-attached multimodal device examined in this present study is useful for detecting foaling.
13
Nasution, M. Alfi Rajabi, i Surya Wiranto. "PROPAGANDA ISSUES OF RACISM THROUGH SOCIAL MEDIA TO TRIGGER SOCIAL VIOLENCE IN PAPUA AND WEST PAPUA IN 2019". Jurnal Pertahanan: Media Informasi ttg Kajian & Strategi Pertahanan yang Mengedepankan Identity, Nasionalism & Integrity 6, nr 2 (11.08.2020): 212. http://dx.doi.org/10.33172/jp.v6i2.857.
Pełny tekst źródłaStreszczenie:
<p>Racism events that took place in the Papua Student Dormitory, Surabaya, East Java had a long tail by causing mass protests and riots in Papua and West Papua from 19 August 2019 to 23 September 2019. Mass riots by Papuans and Papuan native students were triggered by the problem of spreading propaganda on the issue of racism on a massive scale through social media by exploiting the issue of racism that is happening in the city of Surabaya. This study uses propaganda theory, social conflict theory, and national security theory in analyzing these problems. This study uses qualitative research methods with a descriptive analysis approach. Sources of data obtained through interviews, observation, and literature studies. The results showed that the propaganda issue of racism was the cause of mass unrest and social conflict in Papua and West Papua; the propaganda issue of racism is very effective in achieving its broader goals of changing the attitudes and behavior of Papuan and Papuan indigenous students to be destructive and gaining local and international support by creating negative opinions as material to delegitimize and discredit the Government of Indonesia, and the propaganda issue of racism has resulted in damage to social relations with other Indonesian people and the potential for social conflict that can threaten national security.</p>
14
McLennan, Krista. "Why Pain Is Still a Welfare Issue for Farm Animals, and How Facial Expression Could Be the Answer". Agriculture 8, nr 8 (11.08.2018): 127. http://dx.doi.org/10.3390/agriculture8080127.
Pełny tekst źródłaStreszczenie:
Pain is a sensory and emotional experience that significantly affects animal welfare and has negative impacts on the economics of farming. Pain is often associated with common production diseases such as lameness and mastitis, as well as introduced to the animal through routine husbandry practices such as castration and tail docking. Farm animals are prey species which tend not to overtly express pain or weakness, making recognizing and evaluating pain incredibly difficult. Current methods of pain assessment do not provide information on what the animal is experiencing at that moment in time, only that its experience is having a long term negative impact on its behavior and biological functioning. Measures that provide reliable information about the animals’ affective state in that moment are urgently required; facial expression as a pain assessment tool has this ability. Automation of the detection and analysis of facial expression is currently in development, providing further incentive to use these methods in animal welfare assessment.
15
Wei, Zhongcheng, Wenjie Guo, Yunping Zhang, Jieying Zhang i Jijun Zhao. "Bidirectional matching and aggregation network for few-shot relation extraction". PeerJ Computer Science 9 (6.03.2023): e1272. http://dx.doi.org/10.7717/peerj-cs.1272.
Pełny tekst źródłaStreszczenie:
Few-shot relation extraction is used to solve the problem of long tail distribution of data by matching between query instances and support instances. Existing methods focus only on the single direction process of matching, ignoring the symmetry of the data in the process. To address this issue, we propose the bidirectional matching and aggregation network (BMAN), which is particularly powerful when the training data is symmetrical. This model not only tries to extract relations for query instances, but also seeks relational prototypes about the query instances to validate the feature representation of the support set. Moreover, to avoid overfitting in bidirectional matching, the data enhancement method was designed to scale up the number of instances while maintaining the scope of the instance relation class. Extensive experiments on FewRel and FewRel2.0 public datasets are conducted and evaluate the effectiveness of BMAN.
16
Al-Khafaji Enas. "Applications of primary alkylamines in nanoparticles formation and stabilization". International Journal of Research in Pharmaceutical Sciences 11, SPL4 (21.12.2020): 1820–25. http://dx.doi.org/10.26452/ijrps.v11ispl4.4384.
Pełny tekst źródłaStreszczenie:
Fatty amines or primary alkyl-amines like hexylamine, Octylamine, Decylamine, Dodecylamine, Tetradecylamine, Hexadecylamine, and Octadecylamine have been used widely in nanoparticles formation, preparation and for stabilization issue; due to their low toxicity and easily utility. The most common use of fatty amines in many research work that has been reviewed is as capping and stabilizing agent for the nanoparticles, and that is related to their abilities to stabilize nanoparticles and reduce Ostwald ripening after nanoparticles formation. Moreover, Fatty amines surfactants have been reported in many research works to assist the formation of monodisperse size because they can be adsorbed on the surface of nanoparticles which limit variability in nanoparticles size and also they can form a coat around nanoparticles that prevent agglomeration or aggregation of nanoparticles. Also, other uses that have been addressed for fatty amines as they served as hydrophobic part due to hydrocarbon chain tail. These tails for fatty amines especially those with long hydrocarbon chain more than 12 carbons like; Dodecylamine C12, tetradecylamine C14, hexadecylamine C16 and octadecylamine C18 can be fabricated and conjugated with other molecules or polymers for many nanoparticles synthesis which can help in the self-assembly of nanoparticles. Moreover, due to their high boiling point; they used as solvents and reaction catalyst facilitate the formation of nanoparticles. Finally, fatty amines surfactant used as the ligating compound also assist the formation of nanoparticles.
17
Tarasov, Sergei. "Integration of Anatomy Ontologies and Evo-Devo Using Structured Markov Models Suggests a New Framework for Modeling Discrete Phenotypic Traits". Systematic Biology 68, nr 5 (22.01.2019): 698–716. http://dx.doi.org/10.1093/sysbio/syz005.
Pełny tekst źródłaStreszczenie:
Abstract Modeling discrete phenotypic traits for either ancestral character state reconstruction or morphology-based phylogenetic inference suffers from ambiguities of character coding, homology assessment, dependencies, and selection of adequate models. These drawbacks occur because trait evolution is driven by two key processes—hierarchical and hidden—which are not accommodated simultaneously by the available phylogenetic methods. The hierarchical process refers to the dependencies between anatomical body parts, while the hidden process refers to the evolution of gene regulatory networks (GRNs) underlying trait development. Herein, I demonstrate that these processes can be efficiently modeled using structured Markov models (SMM) equipped with hidden states, which resolves the majority of the problems associated with discrete traits. Integration of SMM with anatomy ontologies can adequately incorporate the hierarchical dependencies, while the use of the hidden states accommodates hidden evolution of GRNs and substitution rate heterogeneity. I assess the new models using simulations and theoretical synthesis. The new approach solves the long-standing “tail color problem,” in which the trait is scored for species with tails of different colors or no tails. It also presents a previously unknown issue called the “two-scientist paradox,” in which the nature of coding the trait and the hidden processes driving the trait’s evolution are confounded; failing to account for the hidden process may result in a bias, which can be avoided by using hidden state models. All this provides a clear guideline for coding traits into characters. This article gives practical examples of using the new framework for phylogenetic inference and comparative analysis.
18
Feng, Baoan, i Xingping Zhou. "The focus of public discourse on child abuse in kindergartens: analysis of articles on child abuse in newspapers of China from 2010 to 2017". Problemy Wczesnej Edukacji 43, nr 4 (31.12.2018): 69–76. http://dx.doi.org/10.26881/pwe.2018.43.06.
Pełny tekst źródłaStreszczenie:
As a social phenomenon, child abuse in kindergartens is not only an educational but also a legal issue. This study analyzed 423 critical articles on child abuse in kindergartens published by 103 newspapers in China from 2010 to 2017. The results of the research are as follows: (1) The change of public opinion on child abuse conforms to the law of public opinion development in the latent period, outbreak period, spread period, repetition period, remission period and long tail period of the dissemination of hot topics of public opinion; (2) The range of social groups concerned about child abuse has been expanding year by year, until 2017, a total of 22 categories of social groups have paid attention to child abuse; (3) The focus of public attention on the child abuse incidents includes 23 aspects, such as the supervision responsibility, harm, punishment, system, prevent, treatment and morality. Among them, it mainly focuses on supervision and rule of law, and lacks humanistic care for preschool teachers.
19
Xu, Mengqiao, Ling Zhang, Wen Li i Haoxiang Xia. "Mobility Pattern of Taxi Passengers at Intra-Urban Scale: Empirical Study of Three Cities". Journal of Systems Science and Information 5, nr 6 (20.12.2017): 537–55. http://dx.doi.org/10.21078/jssi-2017-537-19.
Pełny tekst źródłaStreszczenie:
AbstractThe study of human mobility patterns is of both theoretical and practical values in many aspects. For long-distance travel, a few research endeavors have shown that the displacements of human travels follow a power-law distribution. However, controversies remain regarding the issue of the scaling laws of human mobility in intra-urban areas. In this work, we focus on the mobility pattern of taxi passengers by examining five datasets of three metropolitans. Through statistical analysis, we find that the lognormal distribution with a power-law tail can best approximate both the displacement and the duration time of taxi trips in all the examined cities. The universality of the scaling laws of human mobility is subsequently discussed, in view of the analysis of the data. The consistency of the statistical properties of the selected datasets that cover different cities and study periods suggests that, the identified pattern of taxi-based intra-urban travels seems to be ubiquitous over cities and time periods.
20
Cho, Hyo Jong, Ki Won Jeong, Jun Yong Kim i Yun Seon Do. "35‐3: Metasurface‐based Color Filter with Optical Cavity for High Color Purity Displays". SID Symposium Digest of Technical Papers 54, nr 1 (czerwiec 2023): 507–9. http://dx.doi.org/10.1002/sdtp.16604.
Pełny tekst źródłaStreszczenie:
Metasurface‐based color filter have been regarded as good alternatives of conventional color filter causes of their reliability, simple design method, and high resolved pixelization performance. In this study, we designed a novel metasurface‐based color filter with surface plasmons (SPs). The conventional plasmonic color filters (PCFs) have broad transmittance spectra. Consequently, the color purity degrades and this become a fatal issue for practical use. In order to solve the poor wavelength selectivity of the PCFs, we designed a novel PCF integrated with the Fabry‐Perot interferometer (FPI). We added the simple cavity structure over the matching layer of the existing PCF to apply FPI to the PCF. By applying it, the red tail in the long wavelength band of the transmission properties of PCFs were reduced. The color gamut of the suggested filter has increased 2.42 times compared to the conventional PCFs. These improvements are showed the applicability of PCF to various imaging devices.
21
Shahzad, Gulfam, Rashid Rehan i Muhammad Fahim. "Rapid Performance Evaluation of Water Supply Services for Strategic Planning". Civil Engineering Journal 5, nr 5 (21.05.2019): 1197–204. http://dx.doi.org/10.28991/cej-2019-03091324.
Pełny tekst źródłaStreszczenie:
The assessment of existing water supply services was carried out through selected performance indicators with the aim of using that data in future for strategic planning of urban Mardan. The key performance indictors studied were selected to assess both the quantity and quality of water. The quality of water was assessed by turbidity, pH, and E-coli tests for samples collected at the start, middle, and tail end of the distribution system. The quantity of water supplied was measured by calculating discharges from water tapes at the three selected locations in the distribution system. A total of thirty samples were collected from ten union councils out of fourteen covering urban Mardan. A number of issues are highlighted in the overall water supply infrastructure and short, mid, and long term remedial measures are recommended. The results are presented in the form of an interactive map using Google Earth and VBA based dynamic database. It was found that the overall quality of water is generally acceptable for drinking. However, the presence of bacteria is an issue in many cases which needs to be resolved. A significant decrease in discharge is observed in the distribution systems away from the source due to leakages and illegal connections. A comprehensive overhaul of both management and infrastructure is required for sustainable and satisfactory level of services.
22
Liao, Jianwei, Jun Li, Mingwang Zhao, Zhibing Sha i Zhigang Cai. "Read Refresh Scheduling and Data Reallocation against Read Disturb in SSDs". ACM Transactions on Embedded Computing Systems 21, nr 2 (31.03.2022): 1–27. http://dx.doi.org/10.1145/3495254.
Pełny tekst źródłaStreszczenie:
Read disturb is a circuit-level noise in flash-based Solid-State Drives (SSDs), induced by intensive read requests, which may result in unexpected read errors. The approach of read refresh (RR) is commonly adopted to mitigate its negative effects by unconditionally migrating all valid data pages in the RR block to another new block. However, routine RR operations greatly impact the I/O responsiveness of SSDs, because the processing on normal I/O requests must be blocked at the same time. To further reduce the negative effects of read refresh, this article proposes a read refresh scheduling and data reallocation method to deal with two primary issues with respect to an RR operation, including where to place data pages and when to trigger page migrations. Specifically, we first construct a data reallocation model to match the data pages in the RR block and the destination blocks for addressing the issue of where to place the data. The model considers not only the read hotness of pages in the RR block, but also the accumulated read counts of the destination blocks. Moreover, for addressing the issue of when to trigger data migrations, we build a timing decision model to determine the time points for completing page migrations by considering the factors of the intensity of I/Os and the disturb situation on the RR block. Through a series of simulation experiments based on several realistic disk traces, we illustrate that the proposed RR scheduling and data reallocation mechanism can noticeably reduce the read errors by more than 10.3% , on average, and the long-tail latency by between 43.9% and 64.0% at the 99.99th percentile, in contrast to state-of-the-art methods.
23
Yan, Fei, Hui Zhang, Yaogen Li, Yongjia Yang i Yinping Liu. "End-to-End: A Simple Template for the Long-Tailed-Recognition of Transmission Line Clamps via a Vision-Language Model". Applied Sciences 13, nr 5 (4.03.2023): 3287. http://dx.doi.org/10.3390/app13053287.
Pełny tekst źródłaStreszczenie:
Raw image classification datasets generally maintain a long-tailed distribution in the real world. Standard classification algorithms face a substantial issue because many labels only relate to a few categories. The model learning processes will tend toward the dominant labels under the influence of their loss functions. Existing systems typically use two stages to improve performance: pretraining on initial imbalanced datasets and fine-tuning on balanced datasets via re-sampling or logit adjustment. These have achieved promising results. However, their limited self-supervised information makes it challenging to transfer such systems to other vision tasks, such as detection and segmentation. Using large-scale contrastive visual-language pretraining, the Open AI team discovered a novel visual recognition method. We provide a simple one-stage model called the text-to-image network (TIN) for long-tailed recognition (LTR) based on the similarities between textual and visual features. The TIN has the following advantages over existing techniques: (1) Our model incorporates textual and visual semantic information. (2) This end-to-end strategy achieves good results with fewer image samples and no secondary training. (3) By using seesaw loss, we further reduce the loss gap between the head category and the tail category. These adjustments encourage large relative magnitudes between the logarithms of rare and dominant labels. TIN conducted extensive comparative experiments with a large number of advanced models on ImageNet-LT, the largest long-tailed public dataset, and achieved the state-of-the-art for a single-stage model with 72.8% at Top-1 accuracy.
24
Yang, Xiaoyu, Yufei Chen, Xiaodong Yue, Shaoxun Xu i Chao Ma. "T-distributed Spherical Feature Representation for Imbalanced Classification". Proceedings of the AAAI Conference on Artificial Intelligence 37, nr 9 (26.06.2023): 10825–33. http://dx.doi.org/10.1609/aaai.v37i9.26284.
Pełny tekst źródłaStreszczenie:
Real-world classification tasks often show an extremely imbalanced problem. The extreme imbalance will cause a strong bias that the decision boundary of the classifier is completely dominated by the categories with abundant samples, which are also called the head categories. Current methods have alleviated the imbalanced impact from mainly three aspects: class re-balance, decoupling and domain adaptation. However, the existing criterion with the winner-take-all strategy still leads to the crowding problem in the eigenspace. The head categories with many samples can extract features more accurately, but occupy most of the eigenspace. The tail categories sharing the rest of the narrow eigenspace are too crowded together to accurately extract features. Above these issues, we propose a novel T-distributed spherical metric for equalized eigenspace in the imbalanced classification, which has the following innovations: 1) We design the T-distributed spherical metric, which has the characteristics of high kurtosis. Instead of the winner-take-all strategy, the T-distributed spherical metric produces a high logit only when the extracted feature is close enough to the category center, without a strong bias against other categories. 2) The T-distributed spherical metric is integrated into the classifier, which is able to equalize the eigenspace for alleviating the crowding issue in the imbalanced problem. The equalized eigenspace by the T-distributed spherical classifier is capable of improving the accuracy of the tail categories while maintaining the accuracy of the head, which significantly promotes the intraclass compactness and interclass separability of features. Extensive experiments on large-scale imbalanced datasets verify our method, which shows superior results in the long-tailed CIFAR-100/-10 with the imbalanced ratio IR = 100/50. Our method also achieves excellent results on the large-scale ImageNet-LT dataset and the iNaturalist dataset with various backbones. In addition, we provide a case study of the real clinical classification of pancreatic tumor subtypes with 6 categories. Among them, the largest number of PDAC accounts for 315 cases, and the least CP has only 8 cases. After 4-fold cross-validation, we achieved a top-1 accuracy of 69.04%.
25
Xu, Yajing, Haitao Yang, Si Li, Xinyi Wang i Mingfei Cheng. "Contextual Coefficients Excitation Feature: Focal Visual Representation for Relationship Detection". Applied Sciences 10, nr 3 (10.02.2020): 1191. http://dx.doi.org/10.3390/app10031191.
Pełny tekst źródłaStreszczenie:
Visual relationship detection (VRD), a challenging task in the image understanding, suffers from vague connection between relationship patterns and visual appearance. This issue is caused by the high diversity of relationship-independent visual appearance, where inexplicit and redundant cues may not contribute to the relationship detection, even confuse the detector. Previous relationship detection models have shown remarkable progress in leveraging external textual information or scene-level interaction to complement relationship detection cues. In this work, we propose Contextual Coefficients Excitation Feature (CCEF), a focal visual representation, which is adaptively recalibrated from original visual feature responses by explicitly modeling the interdependencies between features and their contextual coefficients. Specifically, contextual coefficients are obtained by calculation of both the spatial coefficients and generated-label ones. In addition, a conditional Wasserstein Generative Adversarial Network (WGAN) regularized with a relationship classification loss is designed to alleviate inadequate training of generated-label coefficients due to long tail distribution of relationship. Experimental results demonstrate the effective improvements of our method on relationship detection. In particular, our method improves the recall from 8.5% to 23.2% of predicting unseen relationship from zero-shot set.
26
Wei, Feng, Shuyu Chen, Jie Jin, Shuai Zhang, Hongwei Zhou i Yingbo Wu. "Adaptive Alleviation for Popularity Bias in Recommender Systems with Knowledge Graph". Security and Communication Networks 2022 (7.04.2022): 1–9. http://dx.doi.org/10.1155/2022/4264489.
Pełny tekst źródłaStreszczenie:
Recommender systems are known to suffer from the popularity bias problem: popular items are recommended frequently, and nonpopular ones rarely, if at all. Prior studies focused on tackling this issue by increasing the number of recommended nonpopular (long-tail) items. However, these methods ignore the users’ personal popularity preferences and increase the exposure rate of the nonpopular items indiscriminately, which may hurt the user experience because different users have diverse interests in popularity. In this work, we propose a novel debias framework with knowledge graph (AWING), which adaptively alleviates popularity bias from the users’ perspective. Concretely, we explore fine-grained preferences (including popularity preference) behind a user-item interaction by using the heterogeneous graph transformer over the knowledge graph embedded with popularity nodes and endow the preferences with explicit semantics. Based on this idea, we can manipulate how much popularity preference affects recommendation results and improves the exposure rate of nonpopular items while considering the popularity preferences of different users. Experiments on public datasets show that the proposed method AWING can effectively alleviate popularity bias and ensure the user experience at the same time. The case study further demonstrates the feasibility of AWING on the explainable recommendation task.
27
Olsson, Mats, Erik Wapstra i Christopher Friesen. "Ectothermic telomeres: it's time they came in from the cold". Philosophical Transactions of the Royal Society B: Biological Sciences 373, nr 1741 (15.01.2018): 20160449. http://dx.doi.org/10.1098/rstb.2016.0449.
Pełny tekst źródłaStreszczenie:
We review the evolutionary ecology and genetics of telomeres in taxa that cannot elevate their body temperature to a preferred level through metabolism but do so by basking or seeking out a warm environment. This group of organisms contains all living things on earth, apart from birds and mammals. One reason for our interest in this synthetic group is the argument that high, stable body temperature increases the risk of malignant tumours if long, telomerase-restored telomeres make cells ‘live forever’. If this holds true, ectotherms should have significantly lower cancer frequencies. We discuss to what degree there is support for this ‘anti-cancer’ hypothesis in the current literature. Importantly, we suggest that ectothermic taxa, with variation in somatic telomerase expression across tissue and taxa, may hold the key to understanding ongoing selection and evolution of telomerase dynamics in the wild. We further review endotherm-specific effects of growth on telomeres, effects of autotomy (‘tail dropping’) on telomere attrition, and costs of maintaining sexual displays measured in telomere attrition. Finally, we cover plant ectotherm telomeres and life histories in a separate ‘mini review’. This article is part of the theme issue ‘Understanding diversity in telomere dynamics'.
28
Santucci, S., K. T. Tallakstad, L. Angheluta, L. Laurson, R. Toussaint i K. J. Måløy. "Avalanches and extreme value statistics in interfacial crackling dynamics". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, nr 2136 (26.11.2018): 20170394. http://dx.doi.org/10.1098/rsta.2017.0394.
Pełny tekst źródłaStreszczenie:
We study the avalanche and extreme statistics of the global velocity of a crack front, propagating slowly along a weak heterogeneous interface of a transparent polymethyl methacrylate block. The different loading conditions used (imposed constant velocity or creep relaxation) lead to a broad range of average crack front velocities. Our high-resolution and large dataset allows one to characterize in detail the observed intermittent crackling dynamics. We specifically measure the size S , the duration D , as well as the maximum amplitude of the global avalanches, defined as bursts in the interfacial crack global velocity time series. Those quantities characterizing the crackling dynamics follow robust power-law distributions, with scaling exponents in agreement with the values predicted and obtained in numerical simulations of the critical depinning of a long-range elastic string, slowly driven in a random medium. Nevertheless, our experimental results also set the limit of such model which cannot reproduce the power-law distribution of the maximum amplitudes of avalanches of a given duration reminiscent of the underlying fat-tail statistics of the local crack front velocities. This article is part of the theme issue ‘Statistical physics of fracture and earthquakes’.
29
Wang, Zhenzhong, Lulu Cao, Wanyu Lin, Min Jiang i Kay Chen Tan. "Robust Graph Meta-Learning via Manifold Calibration with Proxy Subgraphs". Proceedings of the AAAI Conference on Artificial Intelligence 37, nr 12 (26.06.2023): 15224–32. http://dx.doi.org/10.1609/aaai.v37i12.26776.
Pełny tekst źródłaStreszczenie:
Graph meta-learning has become a preferable paradigm for graph-based node classification with long-tail distribution, owing to its capability of capturing the intrinsic manifold of support and query nodes. Despite the remarkable success, graph meta-learning suffers from severe performance degradation when training on graph data with structural noise. In this work, we observe that the structural noise may impair the smoothness of the intrinsic manifold supporting the support and query nodes, leading to the poor transferable priori of the meta-learner. To address the issue, we propose a new approach for graph meta-learning that is robust against structural noise, called Proxy subgraph-based Manifold Calibration method (Pro-MC). Concretely, a subgraph generator is designed to generate proxy subgraphs that can calibrate the smoothness of the manifold. The proxy subgraph compromises two types of subgraphs with two biases, thus preventing the manifold from being rugged and straightforward. By doing so, our proposed meta-learner can obtain generalizable and transferable prior knowledge. In addition, we provide a theoretical analysis to illustrate the effectiveness of Pro-MC. Experimental results have demonstrated that our approach can achieve state-of-the-art performance under various structural noises.
30
Jin, Lisa, Linfeng Song, Lifeng Jin, Dong Yu i Daniel Gildea. "Hierarchical Context Tagging for Utterance Rewriting". Proceedings of the AAAI Conference on Artificial Intelligence 36, nr 10 (28.06.2022): 10849–57. http://dx.doi.org/10.1609/aaai.v36i10.21331.
Pełny tekst źródłaStreszczenie:
Utterance rewriting aims to recover coreferences and omitted information from the latest turn of a multi-turn dialogue. Recently, methods that tag rather than linearly generate sequences have proven stronger in both in- and out-of-domain rewriting settings. This is due to a tagger's smaller search space as it can only copy tokens from the dialogue context. However, these methods may suffer from low coverage when phrases that must be added to a source utterance cannot be covered by a single context span. This can occur in languages like English that introduce tokens such as prepositions into the rewrite for grammaticality. We propose a hierarchical context tagger (HCT) that mitigates this issue by predicting slotted rules (e.g., "besides _") whose slots are later filled with context spans. HCT (i) tags the source string with token-level edit actions and slotted rules and (ii) fills in the resulting rule slots with spans from the dialogue context. This rule tagging allows HCT to add out-of-context tokens and multiple spans at once; we further cluster the rules to truncate the long tail of the rule distribution. Experiments on several benchmarks show that HCT can outperform state-of-the-art rewriting systems by ~2 BLEU points.
31
Povstenko, Y., i T. Kyrylych. "Fractional thermoelasticity problem for an infinite solid with a penny-shaped crack under prescribed heat flux across its surfaces". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, nr 2172 (11.05.2020): 20190289. http://dx.doi.org/10.1098/rsta.2019.0289.
Pełny tekst źródłaStreszczenie:
The time-nonlocal generalization of the Fourier law with the ‘long-tail’ power kernel can be interpreted in terms of fractional calculus and leads to the time-fractional heat conduction equation with the Caputo derivative. The theory of thermal stresses based on this equation was proposed by the first author ( J. Therm. Stresses 28 , 83–102, 2005 ( doi:10.1080/014957390523741 )). In the present paper, the fractional heat conduction equation is solved for an infinite solid with a penny-shaped crack in the case of axial symmetry under the prescribed heat flux loading at its surfaces. The Laplace, Hankel and cos-Fourier integral transforms are used. The solution for temperature is obtained in the form of integral with integrands being the generalized Mittag-Leffler function in two parameters. The associated thermoelasticity problem is solved using the displacement potential and Love’s biharmonic function. To calculate the additional stress field which allows satisfying the boundary conditions at the crack surfaces, the dual integral equation is solved. The thermal stress field is calculated, and the stress intensity factor is presented for different values of the order of the Caputo time-fractional derivative. A graphical representation of numerical results is given. This article is part of the theme issue ‘Advanced materials modelling via fractional calculus: challenges and perspectives’.
32
Liu, Y. J., T. Y. Liao i D. D. Joseph. "A two-dimensional cusp at the trailing edge of an air bubble rising in a viscoelastic liquid". Journal of Fluid Mechanics 304 (10.12.1995): 321–42. http://dx.doi.org/10.1017/s0022112095004447.
Pełny tekst źródłaStreszczenie:
When an air bubble rises in a viscoelastic fluid there is a critical capillary number for cusping and jump in velocity: when the capillary number is below critical, which is about 1 in our data, there is no cusp at the tail of a (smooth) air bubble. For larger volumes, a two-dimensional cusp, sharp in one view and broad in the orthogonal view, is in evidence. Measurements suggest that the cusp tip is in the generic form y = ax2/3 satisfied by analytic cusps. The intervals of volumes for which dramatic changes in air bubble shape take place is very small and the two to ten fold increase in the rise velocity which accompanies the small change of volume could be modelled as a discontinuity. A second drag transition and an orientational transition occurred when U/c > 1 where U is the rise velocity of an air bubble and c is the shear wave speed. For U/c < 1, U is proportional to d2, where d is the equivalent diameter for a sphere of diameter d having the same volume, and when U/c > 1 then U is proportional to d and the Deborah number does not change with U. Moreover the bubble shapes when U/c < 1 are overall prolate (with or without a cusped tail) with the long side parallel to gravity, in contrast to the oblate shapes which are always observed in Newtonian fluids and in viscoelastic fluids with U/c > 1 when inertia is dominant. The formation of cusps occurs in all kinds of columns of different sizes and shapes. Cusping is generic but the orientation of the broad edge with respect to the sidewalls is an issue. There is no preferred orientation in columns with round cross-sections, or in the case of walls far away from the rising bubble. In columns with rectangular cross-sections, three relatively stable configurations can be observed: the cusp can be observed in the wide window and the broad edge in the narrow window; the cusp can be observed in the narrow window and the broad edge in the wide window or, less frequently, the broad edge lies along a diagonal. These orientational and drag alternatives are directly analogous to those which are observed in the settling of long or broad solid bodies (Liu & Joseph 1993).
33
Hedenström, Anders, i Susanne Åkesson. "Ecology of tern flight in relation to wind, topography and aerodynamic theory". Philosophical Transactions of the Royal Society B: Biological Sciences 371, nr 1704 (26.09.2016): 20150396. http://dx.doi.org/10.1098/rstb.2015.0396.
Pełny tekst źródłaStreszczenie:
Flight is an economical mode of locomotion, because it is both fast and relatively cheap per unit of distance, enabling birds to migrate long distances and obtain food over large areas. The power required to fly follows a U-shaped function in relation to airspeed, from which context dependent ‘optimal’ flight speeds can be derived. Crosswinds will displace birds away from their intended track unless they make compensatory adjustments of heading and airspeed. We report on flight track measurements in five geometrically similar tern species ranging one magnitude in body mass, from both migration and the breeding season at the island of Öland in the Baltic Sea. When leaving the southern point of Öland, migrating Arctic and common terns made a 60° shift in track direction, probably guided by a distant landmark. Terns adjusted both airspeed and heading in relation to tail and side wind, where coastlines facilitated compensation. Airspeed also depended on ecological context (searching versus not searching for food), and it increased with flock size. Species-specific maximum range speed agreed with predicted speeds from a new aerodynamic theory. Our study shows that the selection of airspeed is a behavioural trait that depended on a complex blend of internal and external factors. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’.
34
Khodorova, Alla, i Gary R. Strichartz. "Remarkably long-lasting tachyphylaxis of pain responses to ET-1: evidence against central nervous system involvementThis article is one of a selection of papers published in the two-part special issue entitled 20 Years of Endothelin Research." Canadian Journal of Physiology and Pharmacology 88, nr 6 (czerwiec 2010): 668–75. http://dx.doi.org/10.1139/y10-044.
Pełny tekst źródłaStreszczenie:
A profound tachyphylaxis of the acute nocifensive flinching (pain) response to subcutaneous injection of endothelin-1 (ET-1) into the hind paw footpad is shown by the reduced response to a second injection. Flinching from the second injection was 20% ± 5%, 57% ± 18%, 79% ± 35%, and 100% ± 17% of that from the first injection (both 200 µmol/L, 2 nmol) at respective intervals of 24, 30, 48, and 72 h. Inhibition of afferent impulses by local anesthesia of the sciatic nerve, reducing initial flinching to 6%–13% of control, did not affect the tachyphylaxis for the second injection at 24 h. There was no cross-desensitization between formalin and ET-1 injected sequentially into the same paw. Suppression of descending inhibitory effects from endogenous opiates by naloxone (5–8 mg/kg, i.p.), given 30 min before the second ET-1 injection, did not prevent tachyphylaxis. Diffuse effects caused by an initial subcutaneous ET-1 injection into the tail or forepaw resulted in sensitization of the response to ET-1 in the hind paw, rather than tachyphylaxis. In contrast, selective inhibition of local ETA receptors during the initial administration of ET-1, by the antagonist BQ-123 (3.2 mmol/L), reduced tachyphylaxis of nocifensive flinching. Therefore, prolonged pain tachyphylaxis is not due to reduced responsiveness of the CNS, but rather depends on the functional sensitivity or availability of peripheral ETA receptors.
35
Yang, Xia, Jing Zhang i Wei-Xin Ren. "Threshold selection for extreme value estimation of vehicle load effect on bridges". International Journal of Distributed Sensor Networks 14, nr 2 (luty 2018): 155014771875769. http://dx.doi.org/10.1177/1550147718757698.
Pełny tekst źródłaStreszczenie:
In the design and condition assessment of bridges, the extreme vehicle load effects are necessary to be taken into consideration, which may occur during the service period of bridges. In order to obtain an accurate extrapolation of the extreme value based on limited duration, threshold selection is a critical step in the peak-over-threshold method. Overly high threshold results in little information to be used and excessively low threshold leads to large bias in parameters estimation of generalized Pareto distribution. To investigate this issue, 417 days of strain data acquired from the long-term structural health monitoring system of Taiping Lake Bridge in China are employed in this article. According to the tail distribution of the strain data induced by vehicle loads, four homothetic distributions are chosen as its parent distribution, from which lots of random samples are generated by the Monte Carlo method. For each parent distribution, the 100-yearly extreme values at different thresholds are estimated and compared with the theoretical value based on those samples. Then a simple and empirical threshold selection method is proposed and applied to estimate the weekly extreme strain due to vehicle loads on the Taiping Lake Bridge. Results show that the estimate on the basis of the threshold obtained by the proposed method is closer to the measured result than the commonly used methods. The proposed method can be an effective threshold selection tool for the extreme value estimation of vehicle load effect in future engineering practice.
36
Ou, S. Q., J. Gao, D. L. Peng, C. Y. Qi, J. H. Zhang, Y. Meng i B. H. Lu. "First Report of Aphelenchoides besseyi Causing White Tip Disease of Rice in Jilin Province, China". Plant Disease 98, nr 8 (sierpień 2014): 1165. http://dx.doi.org/10.1094/pdis-01-14-0020-pdn.
Pełny tekst źródłaStreszczenie:
White tip disease of rice caused by the plant-parasitic nematode Aphelenchoides besseyi is an important domestic quarantine issue causing heavy yield losses of rice. During a survey for rice diseases in 2013, suspect white tip disease of rice was observed in the cities of Changchun and Gongzhuling, Jinlin Province, China. Leaf tips of susceptible rice varieties were white or yellow, becoming brown or black as necrosis set in. Tips of developing leaves were twisted and wrinkled. The flag leaf became twisted above the panicle until development was inhibited. General stunting of the plant accompanied leaf injury. Panicles were severely reduced and produced small deformed kernels while spikelets were reduced in number. Maturity of panicles was delayed, and secondary panicles arising from the lower nodes of the panicle were sterile. Nematodes were isolated from rice grains of diseased panicles. Key morphological features were determined for females and males. Measurements of females (n = 15) were: body length 612.50 to 735.00 μm (mean 673.75 μm), body width 17.37 to 22.21 μm (mean 19.79 μm), esophagus to gland 64.44 to 68.07 μm (mean 66.26 μm), and tail 34.41 to 41.29 μm (mean 37.85 μm). Females had a relatively short ovary with oocytes arranged in several lines; posterior uterine branch two to four times as long as body width; and tail tapering, conoid, with terminus bearing a mucro with four processes arranged in a shape somewhat that of a star. Measurements of males (n = 22) were: body length 483.39 to 580.00 μm (mean 531.70 μm), body width 14.46 to 17.12 μm (mean 15.79 μm), esophagus to gland 63.97 to 66.42 μm (mean 65.20 μm), and tail 30.38 to 36.45 μm (mean 33.41 μm). Males had a curved tail about 180° when relaxed, three pairs of ventrosubmedian papillae with the first one adanal, spicula curved with a slight basal process, and terminus bearing four mucrones arranged variably. Both males and females had lateral field occupying one fourth of the body width, marked by four incisures; delicate cephalic framework; small spear with moderate-size basal knobs; excretory pore was anterior to nerve ring; and intestine joined to esophagus immediately behind median bulb (3). All morphological data and characters were consistent with A. besseyi. Molecular diagnosis as A. besseyi was confirmed after DNA was extracted from nematodes (n = 16) and the templates were used in PCR analysis. The internal transcribed spacer region (ITS) of rDNA was amplified with primers TW81 and AB28 (2). The size of PCR product was 842 bp, and this sequence (KJ009342) was submitted to GenBank and was 98% similar with that of A. besseyi isolates from India (JF826519, JF93390, JF826517, JF826518) and Russia (EU186069). Molecular identification was further confirmed by amplifying part of the ITS region and part of the 5.8 gene of rDNA using the A. besseyi-specific primers BSF and BSR (1). The amplification yielded a 312-bp product specific to A. besseyi. Morphological and molecular data confirmed that the pathogen responsible for white tip disease in Changchun and Gongzhuling was A. besseyi. While this nematode has been reported from many rice-producing areas in China, this is the first detection of A. besseyi in Jilin Province, China. References: (1) R. Q. Cui et al. Plant Quarantine (Chinese) 24:10-12, 2010. (2) S. A. Subbotin et al. Nematology 2:153, 2000. (3) G. Thorne. Principles of Nematology. McGraw-Hill, New York, 1972.
37
V, Pavithra. "Detection of Hate Speech and Offensive Language in Twitter Using Sentiment Analysis". International Journal for Research in Applied Science and Engineering Technology 9, nr 8 (31.08.2021): 948–52. http://dx.doi.org/10.22214/ijraset.2021.37281.
Pełny tekst źródłaStreszczenie:
Abstract: The dramatic development of online media, for example, Twitter and local area gatherings has upset correspondence and content distributing, but at the same time is progressively misused for the spread of disdain discourse and the association of disdain based exercises. The secrecy and portability managed by such media has made the rearing and spread of disdain discourse – in the long run prompting disdain wrongdoing – easy in a virtual land scape past the domains of conventional law requirement. Existing techniques in the identification of disdain discourse principally cast the issue as a regulated report grouping task [33]. These can be partitioned into two classifications: one depends on manual element designing that are then devoured by calculations, for example, SVM, Naive Bayes, and Logistic Regression [3, 9, 11, 15, 19, 23, 35–39] (exemplary techniques); the other addresses the later profound learning worldview that utilizes neural organizations to consequently learn multi-facets of dynamic highlights from crude information [13, 26, 30, 34] (profound learning strategies). In this technique We show that it is a significantly more testing task, as our examination of the language in the commonplace datasets shows that disdain discourse needs interesting, discriminative highlights and hence is found in the 'long tail' in a dataset that is hard to find. We then, at that point propose Deep Neural Network structures filling in as highlight extractors that are especially powerful for catching the semantics of disdain discourse. Our techniques are assessed on the biggest assortment of disdain discourse datasets dependent on Twitter, and are demonstrated to have the option to beat best in class by up to 6 rate focuses in large scale normal F1, or 9 rate focuses in the seriously difficult instance of recognizing derisive substance. As an intermediary to evaluate and think about the semantic attributes of disdain and non-disdain Tweets, we additionally propose to contemplate the 'uniqueness' of the jargon for each class. Keywords: Classic Methods; DNN; Detection of hate speech and offensive language in Twitter; Sentimental Analysis
38
Cochard, A., O. Lengliné, K. J. Måløy i R. Toussaint. "Thermally activated crack fronts propagating in pinning disorder: simultaneous brittle/creep behaviour depending on scale". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, nr 2136 (26.11.2018): 20170399. http://dx.doi.org/10.1098/rsta.2017.0399.
Pełny tekst źródłaStreszczenie:
We study theoretically the propagation of a crack front in mode I along an interface in a disordered elastic medium, with a numerical model considering a thermally activated rheology, toughness disorder and long-range elastic interactions. This model reproduces not only the large-scale dynamics of the crack front position in fast or creep loading regimes, but also the small-scale self-affine behaviour of the front. Two different scaling laws are predicted for the front morphology, with a Hurst exponent of 0.5 at small scales and a logarithmic scaling law at large scales, consistently with experiments. The prefactor of these scaling laws is expressed as a function of the temperature, and of the quenched disorder characteristics. The cross-over between these regimes is expressed as a function of the quenched disorder amplitude, and is proportional to the average energy release rate, and to the inverse of temperature. This model captures as well the experimentally observed local velocity fluctuation probability distribution, with a high-velocity tail P ( v )∼ v −2.6 . This feature is shown to arise when the quenched disorder is sufficiently large, whereas smaller toughness fluctuations lead to a lognormal-like velocity distribution. Overall, the system is shown to obey a scaling determined by two distinct mechanisms as a function of scale: namely, the large scales display fluctuations similar to an elastic line in an annealed noise excited as the average front travels through the pinning landscape, while small scales display a balance between thresholds in possible elastic forces and quenched disorder. This article is part of the theme issue ‘Statistical physics of fracture and earthquakes’.
39
Crisóstomo, Luís, Romeu A. Videira, Ivana Jarak, Kristina Starčević, Tomislav Mašek, Luís Rato, João F. Raposo, Rachel L. Batterham, Pedro F. Oliveira i Marco G. Alves. "Diet during early life defines testicular lipid content and sperm quality in adulthood". American Journal of Physiology-Endocrinology and Metabolism 319, nr 6 (1.12.2020): E1061—E1073. http://dx.doi.org/10.1152/ajpendo.00235.2020.
Pełny tekst źródłaStreszczenie:
Childhood obesity is a serious concern associated with ill health later in life. Emerging data suggest that obesity has long-term adverse effects upon male sexual and reproductive health, but few studies have addressed this issue. We hypothesized that exposure to high-fat diet during early life alters testicular lipid content and metabolism, leading to permanent damage to sperm parameters. After weaning ( day 21 after birth), 36 male mice were randomly divided into three groups and fed with a different diet regimen for 200 days: a standard chow diet (CTRL), a high-fat diet (HFD) (carbohydrate: 35.7%, protein: 20.5%, and fat: 36.0%), and a high-fat diet for 60 days, then replaced by standard chow (HFDt). Biometric and metabolic data were monitored. Animals were then euthanized, and tissues were collected. Epididymal sperm parameters and endocrine parameters were evaluated. Testicular metabolites were extracted and characterized by 1H-NMR and GC-MS. Testicular mitochondrial and antioxidant activity were evaluated. Our results show that mice fed with a high-fat diet, even if only until early adulthood, had lower sperm viability and motility, and higher incidence of head and tail defects. Although diet reversion with weight loss during adulthood prevents the progression of metabolic syndrome, testicular content in fatty acids is irreversibly affected. Excessive fat intake promoted an overaccumulation of proinflammatory n-6 polyunsaturated fatty acids in the testis, which is strongly correlated with negative effects upon sperm quality. Therefore, the adoption of high-fat diets during early life correlates with irreversible changes in testicular lipid content and metabolism, which are related to permanent damage to sperm quality later in life.
40
Chen, Scott A., i Anthony L. Vaccarino. "Tolerance to Morphine Analgesia: Influence of Pain and Method of Morphine Delivery". Pain Research and Management 5, nr 4 (2000): 279–85. http://dx.doi.org/10.1155/2000/842034.
Pełny tekst źródłaStreszczenie:
Whether some kinds of pain can modify the development of tolerance to morphine analgesia is a controversial issue. Clinically, the development of tolerance is often difficult to establish because many factors can contribute to a decline in analgesic coverage, including disease progression. Basic animal research designed to examine tolerance provides the experimental control necessary to differentiate 'real' tolerance from other variables that can influence morphine analgesia. The present study examines the effects of inflammation induced by complete Freund's adjuvant (CFA) on the development of tolerance to morphine analgesia produced by two different methods of morphine delivery - repeated bolus injections and continuous infusion. Male Long-Evans hooded rats were injected with CFA (0.2 mL) into the right hind paw under sodium pentobarbital anesthesia or were given anesthesia alone. Starting 24 h later, rats either received an injection of morphine (20 mg/kg, intraperitoneal) on four consecutive days or were implanted with a 72 h osmotic minipump that delivered 80 mg/kg morphine over a similar time period. Control animals received saline injections or were implanted with empty minipumps. After 24 h, sensitivity to morphine-induced analgesia was measured by the tail-immersion test (water maintained at 52°C) using a cumulative dosing procedure. It was found that CFA attenuated tolerance to the morphine analgesia that was induced by intraperitoneal injections of morphine. In contrast, when morphine was delivered via osmotic minipumps, significant analgesic tolerance was observed in animals that received morphine in the presence of CFA but not in those that received morphine in the absence of CFA. These results show the importance of the method used to deliver morphine in determining the effects of pain on the development of tolerance to morphine analgesia.
41
Liu, Peng, i Yanyan Zheng. "Precision Measurement of the Return Distribution Property of the Chinese Stock Market Index". Entropy 25, nr 1 (24.12.2022): 36. http://dx.doi.org/10.3390/e25010036.
Pełny tekst źródłaStreszczenie:
In econophysics, the analysis of the return distribution of a financial asset using statistical physics methods is a long-standing and important issue. This paper systematically conducts an analysis of composite index 1 min datasets over a 17-year period (2005–2021) for both the Shanghai and Shenzhen stock exchanges. To reveal the differences between Chinese and mature stock markets, we precisely measure the property of the return distribution of the composite index over the time scale Δt, which ranges from 1 min to almost 4000 min. The main findings are as follows: (1) The return distribution presents a leptokurtic, fat-tailed, and almost symmetrical shape that is similar to that of mature markets. (2) The central part of the return distribution is described by the symmetrical Lévy α-stable process, with a stability parameter comparable with a value of about 1.4, which was extracted for the U.S. stock market. (3) The return distribution can be described well by Student’s t-distribution within a wider return range than the Lévy α-stable distribution. (4) Distinctively, the stability parameter shows a potential change when Δt increases, and thus a crossover region at 15 < Δt < 60 min is observed. This is different from the finding in the U.S. stock market that a single value of about 1.4 holds over 1 ≤ Δt ≤ 1000 min. (5) The tail distribution of returns at small Δt decays as an asymptotic power law with an exponent of about 3, which is a widely observed value in mature markets. However, it decays exponentially when Δt ≥ 240 min, which is not observed in mature markets. (6) Return distributions gradually converge to a normal distribution as Δt increases. This observation is different from the finding of a critical Δt = 4 days in the U.S. stock market.
42
Sawaengwong, Thanchanok, Sirinthorn Sunthornthummas, Komwit Surachat, Thassanant Atithep, Achariya Rangsiruji, Siriruk Sarawaneeyaruk i Onanong Pringsulaka. "Isolation and Characterization of Lytic Bacteriophages against Aeromonas dhakensis Isolated from Water in Thailand". Journal of Current Science and Technology 13, nr 3 (30.08.2023): 551–63. http://dx.doi.org/10.59796/jcst.v13n3.2023.932.
Pełny tekst źródłaStreszczenie:
Phage therapy has emerged as a potential solution to the issue of multidrug-resistant bacteria. In this study, a novel bacteriophage vB_AdhS_M4 , which infects Aeromonas dhakensis, was isolated. A. dhakensis strains were isolated from water samples in Thailand and identified by biochemical and 16S rDNA sequence analysis. Four isolates, namely AM, NGP8, AK3, and SBKN4 were identified as A. dhakensis and used as hosts for phage isolation. Only 1 phage, vB_AdhS_M4, was obtained using A. dhakensis AM as host. Phage vB_AdhS_M4 morphology, host range, one-step growth curve, pH and temperature stability and genome were investigated. Transmission electron microscopy revealed that vB_AdhS_M4 has an icosahedral head of 64.8 ± 0.51 nm and a long tail of 185.4 ± 0.48 nm, suggesting that it belongs to the Siphoviridae family. Phage vB_AdhS_M4 had a latent period of 50 mins and a mean burst size of approximately 48 phage particles per infected cell. Our study on host-range determination demonstrated that this phage was specific for infecting A. dhakensis. Phage vB_AdhS_M4 was stable within a pH range of 4-7 and at temperatures ranging from 4 to 45 °C. The complete genome of Aeromonas phage vB_AdhS_M4 is 61,429 bp in length, with a G+C content of 61.7% and 77 open reading frames. In vitro A. dhakensis growth inhibition were observed with vB_AdhS_M4 at various MOIs. The greatest reduction in cell count occurred during the first 6-12 h of incubation with the phage, compared to the uninfected bacterial control, at all MOIs tested. Although the bacteria regrew after 24 h of incubation with the phage, the bacterial count remained lower than that of the control throughout the entire 48-h period. Based on these findings, it appears that vB_AdhS_M4 could be a valuable tool for biocontrol of A. dhakensis in aquaculture.
43
Bregar, Klemen, Andrej Hrovat i Mihael Mohorčič. "UWB Radio-Based Motion Detection System for Assisted Living". Sensors 21, nr 11 (23.05.2021): 3631. http://dx.doi.org/10.3390/s21113631.
Pełny tekst źródłaStreszczenie:
Because of the ageing population, the demand for assisted living solutions that can help prolonging independent living of elderly at their homes with reduced interaction with caregivers is rapidly increasing. One of the most important indicators of the users’ well-being is their motion and mobility inside their homes, used either on its own or as contextual information for other more complex activities such as cooking, housekeeping or maintaining personal hygiene. In monitoring users’ mobility, radio frequency (RF) communication technologies have an advantage over optical motion detectors because of their penetrability through the obstacles, thus covering greater areas with fewer devices. However, as we show in this paper, RF links exhibit large variations depending on channel conditions in operating environment as well as the level and intensity of motion, limiting the performance of the fixed motion detection threshold determined on offline or batch measurement data. Thus, we propose a new algorithm with an online adaptive motion detection threshold that makes use of channel impulse response (CIR) information of the IEEE 802.15.4 ultra-wideband (UWB) radio, which comprises an easy-to-install robust motion detection system. The online adaptive motion detection (OAMD) algorithm uses a sliding window on the last 100 derivatives of power delay profile (PDP) differences and their statistics to set the threshold for motion detection. It takes into account the empirically confirmed observation that motion manifests itself in long-tail samples or outliers of PDP differences’ probability density function. The algorithm determines the online threshold by calculating the statistics on the derivatives of the 100 most recent PDP differences in a sliding window and scales them up in the suitable range for PDP differences with multiplication factors defined by a data-driven process using measurements from representative operating environments. The OAMD algorithm demonstrates great adaptability to various environmental conditions and exceptional performance compared to the offline batch algorithm. A motion detection solution incorporating the proposed highly reliable algorithm can complement and enhance various assisted living technologies to assess user’s well-being over long periods of time, detect critical events and issue warnings or alarms to caregivers.
44
Zuckerman, Tod I. "Issues and answers concerning the allocation of long‐tail claims". Environmental Claims Journal 12, nr 3 (marzec 2000): 71–159. http://dx.doi.org/10.1080/10406020009355127.
Pełny tekst źródła
45
Zhang, Yan, Xiuxiang An, JoAnne Stubbe i Mingxia Huang. "Investigation of in Vivo Roles of the C-terminal Tails of the Small Subunit (ββ′) of Saccharomyces cerevisiae Ribonucleotide Reductase". Journal of Biological Chemistry 288, nr 20 (25.03.2013): 13951–59. http://dx.doi.org/10.1074/jbc.m113.467001.
Pełny tekst źródłaStreszczenie:
The small subunit (β2) of class Ia ribonucleotide reductase (RNR) houses a diferric tyrosyl cofactor (Fe2III-Y•) that initiates nucleotide reduction in the large subunit (α2) via a long range radical transfer (RT) pathway in the holo-(α2)m(β2)n complex. The C-terminal tails of β2 are predominantly responsible for interaction with α2, with a conserved tyrosine residue in the tail (Tyr356 in Escherichia coli NrdB) proposed to participate in cofactor assembly/maintenance and in RT. In the absence of structure of any holo-RNR, the role of the β tail in cluster assembly/maintenance and its predisposition within the holo-complex have remained unknown. In this study, we have taken advantage of the unusual heterodimeric nature of the Saccharomyces cerevisiae RNR small subunit (ββ′), of which only β contains a cofactor, to address both of these issues. We demonstrate that neither β-Tyr376 nor β′-Tyr323 (Tyr356 equivalent in NrdB) is required for cofactor assembly in vivo, in contrast to the previously proposed mechanism for E. coli cofactor maintenance and assembly in vitro. Furthermore, studies with reconstituted-ββ′ and an in vivo viability assay show that β-Tyr376 is essential for RT, whereas Tyr323 in β′ is not. Although the C-terminal tail of β′ is dispensable for cofactor formation and RT, it is essential for interactions with β and α to form the active holo-RNR. Together the results provide the first evidence of a directed orientation of the β and β′ C-terminal tails relative to α within the holoenzyme consistent with a docking model of the two subunits and argue against RT across the β β′ interface.
46
Sjøvaag, Helle, i Nina Kvalheim. "Eventless news: Blindspots in journalism and the 'long tail' of news content". Journal of Applied Journalism & Media Studies 8, nr 3 (1.11.2019): 291–310. http://dx.doi.org/10.1386/ajms_00003_1.
Pełny tekst źródłaStreszczenie:
The news media is frequently criticized for ignoring, missing or overseeing important, socio-politically relevant news. Such journalistic blindspots are often part of the 'long' news agenda, requiring resources, in-depth knowledge and investigation. In this article, we analyse what news topics are most infrequently covered by the media ‐ the micro-categories of content analysis. A content analysis of 70 news outlets in Norway (n=8182) reveals that the news topics receiving less than 1 per cent of coverage are social issues, international crime and the economy. This bottom-up perspective demonstrates that under-reported news constitutes predominantly 'eventless' issues, sustaining event-centredness as an agenda-setting news value. Finding that more than half of the content categories in the Norwegian corpus receive less than 1 per cent coverage, we propose, however, that the sum of these blindspots engenders a 'long tail' of journalistic coverage that together facilitates news diversity.
47
Bar-Isaac, Heski, Guillermo Caruana i Vicente Cuñat. "Search, Design, and Market Structure". American Economic Review 102, nr 2 (1.04.2012): 1140–60. http://dx.doi.org/10.1257/aer.102.2.1140.
Pełny tekst źródłaStreszczenie:
The Internet has made consumer search easier, with consequences for prices, industry structure, and the kinds of products offered. We provide an industry model with strategic design choices that explores these issues. A polarized market structure results: some firms choose designs aimed at broad-based audiences, while others target narrow niches. We analyze the effect of reduced search costs, finding results consistent with the reported prevalence of niche goods and long-tail and superstar phenomena. In particular, the model suggests that long-tail effects arise when there is a wide range of potential designs, relative to vertical heterogeneity among firms. JEL: D11, D21, D83, L11, L86, M31
48
Wang, Dawei, Xiaohu Shao, Guowei Zhang, Shuxian Yao, Xielai Zhou, Jianhua Mao, Zhugang Wang, Zhu Chen i Saijuan Chen. "Targeting Factor Xa Expression in Platelets As a Potential Gene Therapy Strategy for Hemophilia with Inhibitors". Blood 128, nr 22 (2.12.2016): 1171. http://dx.doi.org/10.1182/blood.v128.22.1171.1171.
Pełny tekst źródłaStreszczenie:
Abstract The development of inhibitory antibodies (inhibitors) is a critical issue in the replacement therapy of hemophilia. The effective therapy of hemophilia with inhibitors is still an urgent demand. In the coagulation cascade, factor X (FX) is the common point of both intrinsic and extrinsic pathway. FX is activated to factor Xa (FXa) by either factor IXa (FIXa)/factor VIIIa (FVIIIa) or factor VIIa (FVIIa)/tissue factor (TF) complexes. FXa forms a prothrombinase complex with factor Va (FVa), and activates prothrombin to thrombin. Since FXa activates prothrombin very efficiently and this process bypasses FIX and FVIII, it has been tried as a bypassing agent in the treatment of hemophilia with inhibitors for a long time. It was found that infusion of FXa in the plasma could alleviate the bleeding phenotype of hemophilia animals. However, studies disclosed that the half-life of FXa is too short to be an effective bypassing agent. Furthermore, improved plasma FXa concentration also increases the risk of disseminated intravascular coagulation (DIC). A protein ectopically expressed in platelets can be stored in platelets, and it can be released during the activation of platelets. Here, we hypothesize that if FXa can be targeted expressed and stored in platelets, the half-life of FXa could be increased, while at the same time the risk of DIC could be largely limited. When platelets are activated at the injury site, the stored FXa can be released and activate prothrombin on the surface of platelets, so as to initiate the blood coagulation. Thus, this platelet-stored FXa could be used in the treatment of hemophilia A (HA) and hemophilia B (HB) with inhibitors. To prove our hypothesis, we constructed a platelet-targeted FXa expression cassette (2bFXa) by putting FXa under the control of GPαIIb promoter. Then we made the corresponding lentiviral vector with this 2bFXa cassette. The 2bFXa lentiviral vector was used to transduce hematopoietic stem cells (HSCs) collected from HA and HB mice, the modified HSCs were then transplanted back into the lethally irradiated corresponding HA and HB recipient mice. We collected plasma and platelets from the recipients. FXa was successfully detected in the platelets but not in the plasma of both HA and HB recipients by either an FXa activity assay or FX ELISA. The level of platelet-stored FXa remains constant throughout the experiment. Platelet release assay indicates almost 85.7% stored FXa can be released after the stimulation of platelets. The storage of FXa in platelets was also demonstrated by confocal microscopy and flow cytometry analysis. We then carried out a tail clip survival test to evaluate the phenotypic correction of recipients, all HA and HB recipient mice survived the tail clip challenge, demonstrating the platelet-stored FXa is biologically functional. We also tested the same strategy on HA mice with inhibitors and acquired the same results, indicating that the strategy is effective for HA with inhibitors. During the whole period of experiment, the recipient mice were all in good health. We also kept on monitoring the complete blood cell counts for 48 weeks and the cell numbers remained in normal range, indicating that the blood cells were successfully recovered in the recipients. Taken together, our proof of principle studies suggest that targeting FXa expression in platelets could facilitate the storage of FXa in platelets and would not cause obvious FXa leakage. The platelet-stored FXa is active and can be released with the activation of platelets and corrects the bleeding phenotype of HA and HB mice. This new gene therapy method could eliminate the shortage of FXa and be functional in the treatment of hemophilia with inhibitors. Disclosures No relevant conflicts of interest to declare.
49
Nousch, Laura, Mathias Hartmann i Alexander Michaelis. "Improvements of Micro-CHP SOFC System Operation by Efficient Dynamic Simulation Methods". Processes 9, nr 7 (26.06.2021): 1113. http://dx.doi.org/10.3390/pr9071113.
Pełny tekst źródłaStreszczenie:
Solid Oxide Fuel Cell (SOFC) technology is of high interest for stationary decentralized generation of electricity and heat in combined heat and power systems (CHP) for the residential sector. Application scenarios for SOFC systems in an electricity-regulated mode play an important role, especially in places where an electrical grid connection is not available or rather unstable. The advantages of SOFC systems are the high fuel flexibility and the high efficiencies also under partial load operation compared to other decentralized power generation technologies. Due to the long, energy-consuming system heat-up and the limited partial load capability, SOFC systems do not reach the performance of conventional power generation technologies. Furthermore, stack thermal cycling is associated with power degradation and should be minimized. In this paper, the improvement of these drawbacks are investigated for hotbox-based SOFC systems in the 1 kWel-class for residential applications. Since experimental investigations of the high-temperature systems are limited, modeling tools are established, enabling the visualization of internal system characteristics and providing the opportunity to simulate system operation in critical regions. To achieve this, a methodology for dynamic SOFC system modeling in a process engineering manner is developed based on the modeling language Modelica. A suitable approach is particularly important for modeling and simulation of the strong thermal interaction between the hot system components within the hotbox. The parametrized and validated models are used for the investigation of different dynamic effects, such as the system heat-up and the operation in low partial load points. A second reduced thermal system model aims for annual simulations of the SOFC system together with a battery to investigate the number of thermal cycles and the advantage of a hot standby operation. As a result, it is found that an adequate control of the power input at the start-up device and the cathode air flow has a high improvement potential to increase the stack heating rate and accelerate the heat-up in an energy-saving way. The hotbox-internal thermal management is identified as a crucial issue to reach low partial load points. To avoid the risk of stack cooling, lower heat losses and/or additional heat sources are of importance. Furthermore, the robustness of the tail gas oxidizer is found to be crucial for a higher load flexibility during partial load and the end of life stack operation. The annual simulation results indicate that operating the battery hybrid system with a hot standby mode requires much lower battery capacity for a high grid independence and a complete avoidance of system shutdown and associated power degradation.
50
Fink, Amy J. "Getting the Big Picture on Nanotechnology Insurance Issues: Addressing Coverage Issues for Long Tail Claims Can Help Prevent Big Headaches". Environmental Claims Journal 19, nr 1-2 (14.06.2007): 17–25. http://dx.doi.org/10.1080/10406020701458892.
Pełny tekst źródła