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Experiments that led to the first gene-edited babies: the ethical failings and the urgent need for better governance

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2019年第1期20卷 32-38页

作者： Jing-ru LI simon walker Jing-bao NIE Xin-qing ZHANG Bioethics Center Dunedin School of Medicine University of Otago School of Humanities and Social Sciences Peking Union Medical College

The rapid developments of science and technology in China over recent decades, particularly in biomedical research, have brought forward serious challenges regarding ethical governance. Recently, Jian-kui HE, a Chinese scientist, claimed to have "created" the first gene-edited babies, designed to be naturally immune to the human immunodeficiency virus(HIV). The news immediately triggered widespread criticism, denouncement, and debate over the scientific and ethical legitimacy of HE’s genetic experiments. China’s guidelines and regulations have banned germline genome editing on human embryos for clinical use because of scientific and ethical concerns, in accordance with the international consensus. HE’s human experimentation has not only violated these Chinese regulations, but also breached other ethical and regulatory norms. These include questionable scientific value, unreasonable risk-benefit ratio, illegitimate ethics review, invalid informed consent, and regulatory misconduct. This series of ethical failings of HE and his team reveal the institutional failure of the current ethics governance system which largely depends on scientist’s self-regulation. The incident highlights the need for urgent improvement of ethics governance at all levels, the enforcement of technical and ethical guidelines, and the establishment of laws relating to such bioethical issues.

关键词： Jian-kui HE Human germline gene editing Human immunodeficiency virus (HIV) Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 Ethical review

Neonatal lamb mortality:major risk factors and the potential ameliorative role of melatonin

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Journal of Animal Science and Biotechnology 2021年第2期12卷 451-461页

作者： Tom Flinn David O.Kleemann Alyce M.Swinbourne Jennifer M.Kelly Alice C.Weaver simon K.walker Kathryn L.Gatford Karen L.Kind William H.E.J.van Wettere Davies Livestock Research Centre School of Animal and Veterinary SciencesThe University of AdelaideRoseworthySAAustralia Turretfield Research Centre South Australian Research and Development InstituteRosedaleSAAustralia Robinson Research Institute Adelaide Medical SchoolThe University of AdelaideAdelaideSAAustralia

High incidences of pre-weaning mortality continue to limit global sheep production,constituting a major economic and welfare *** significant advances in genetics,nutrition,and management,the proportion of lamb deaths has remained stable at 15–20%over the past four *** is mounting evidence that melatonin can improve outcomes in compromised ovine pregnancies via enhanced uterine bloodflow and neonatal *** review provides an overview of the major risk factors and underlying mechanisms involved in perinatal lamb mortality and discusses the potential of melatonin treatment as a remedial *** pregnant ewes with melatonin enhances uterine bloodflow and fetal oxygenation,and potentially birthweight and neonatal thermogenic *** freely crosses the ovine placenta and blood-brain barrier and provides neuroprotection to the fetal lamb during periods of chronic and acute hypoxia throughout gestation,with improved behavioural outcomes in hypoxic *** current literature provides strong evidence that maternal melatonin treatment improves outcomes for lambs which experience compromised in utero development or prolonged parturition,though to date this has not been investigated in livestock production *** such there is a clear basis for continued research into the effects of maternal melatonin supplementation during gestation on pre-weaning survival under extensive production conditions.

关键词： Lamb survival Melatonin Neonatal mortality Reproduction Sheep

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帐篷

数字时代 2013年第9期 81-85页

作者： simon Osborne-walker

相信每个都市人都时而有逃离喧嚣的念头，科技爱好者们自不例外。哪怕仅仅是到郊外找个僻静的地方，支上帐篷美美地睡上一觉，也能即刻恢复充满斗志的自然状态吧……

关键词：帐篷自然状态都市人

Data-driven diagnosis of high temperature PEM fuel cells based on the electrochemical impedance spectroscopy: Robustness improvement and evaluation

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Journal of Energy Chemistry 2024年第9期96卷 544-558页

作者： Dan Yu Xingjun Li Samuel simon Araya simon Lennart Sahlin Vincenzo Liso Department of Energy Aalborg UniversityAalborg 9220Denmark walker Department of Mechanical Engineering The University of Texas at AustinAustinTX 78712USA Materials Research and Technology Development Luxembourg Institute of Science and Technology(LIST)4422 BelvauxLuxembourg

Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a critical and challenging task in real application. To enhance the robustness of diagnosis and achieve a more thorough evaluation of diagnostic performance, a robust diagnostic procedure based on electrochemical impedance spectroscopy (EIS) and a new method for evaluation of the diagnosis robustness was proposed and investigated in this work. To improve the diagnosis robustness: (1) the degradation mechanism of different faults in the high temperature PEM fuel cell was first analyzed via the distribution of relaxation time of EIS to determine the equivalent circuit model (ECM) with better interpretability, simplicity and accuracy;(2) the feature extraction was implemented on the identified parameters of the ECM and extra attention was paid to distinguishing between the long-term normal degradation and other faults;(3) a Siamese Network was adopted to get features with higher robustness in a new embedding. The diagnosis was conducted using 6 classic classification algorithms—support vector machine (SVM), K-nearest neighbor (KNN), logistic regression (LR), decision tree (DT), random forest (RF), and Naive Bayes employing a dataset comprising a total of 1935 collected EIS. To evaluate the robustness of trained models: (1) different levels of errors were added to the features for performance evaluation;(2) a robustness coefficient (Roubust_C) was defined for a quantified and explicit evaluation of the diagnosis robustness. The diagnostic models employing the proposed feature extraction method can not only achieve the higher performance of around 100% but also higher robustness for diagnosis models. Despite the initial performance being similar, the KNN demonstrated a superior robustness after feature selection and re-embedding by triplet-loss method, which sug

关键词： PEM fuel cell Data-driven diagnosis Robustness improvement and evaluation Electrochemical impedance spectroscopy

Review of the impact of heat stress on reproductive performance of sheep

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Journal of Animal Science and Biotechnology 2021年第3期12卷 859-876页

作者： William H.E.J.van Wettere Karen L.Kind Kathryn L.Gatford Alyce M.Swinbourne Stephan T.Leu Peter T.Hayman Jennifer M.Kelly Alice C.Weaver David O.Kleemann simon K.walker The University of Adelaide School of Animal and Veterinary SciencesDavies Livestock Research CentreRoseworthy CampusMudla Wirra RdRoseworthySouth Australia 5371Australia The University of Adelaide Robinson Research InstituteAdelaide Medical SchoolNorth TerraceAdelaideSouth Australia 5000Australia The University of Adelaide School of AgricultureFood and WineWaite Research InstituteUrrbraeSouth Australia 5064Australia South Australian Research and Development Institute Primary Industries and Regions SAGovernment of South AustraliaClimate ApplicationsWaite Research PrecinctUrrbraeSouth Australia 5064Australia South Australian Research and Development Institute Primary Industries and Regions SAReproductive BiologyLivestock SciencesTurretfield Research Centre129 Holland RdRosedaleSouth Australia 5350Australia

Heat stress significantly impairs reproduction of sheep,and under current climatic conditions is a significant risk to the efficiency of the meat and wool production,with the impact increasing as global temperatures *** from field studies and studies conducted using environmental chambers demonstrate the effects of hot temperatures(≥32℃)on components of ewe fertility(oestrus,fertilisation,embryo survival and lambing)are most destructive when experienced from 5 d before until 5 d after *** controlled studies also demonstrate that ram fertility,as measured by rates of fertilisation and embryo survival,is reduced when mating occurs during the period 14 to 50 d ***,the contribution of the ram to heat induced reductions in flock fertility is difficult to determine *** primarily on temperature controlled studies,it is clear that sustained exposure to high temperatures(≥32℃)during pregnancy reduces lamb birthweight and will,therefore,decrease lamb survival under field *** is concluded that both ewe and ram reproduction is affected by relatively modest levels of heat stress(≥32℃)and this is a concern given that a significant proportion of the global sheep population experiences heat stress of this magnitude around mating and during *** this,strategies to limit the impacts of the climate on the homeothermy,behaviour,resource use and reproduction of extensively grazed sheep are limited,and there is an urgency to improve knowledge and to develop husbandry practices to limit these impacts.

关键词： Fertility Heat stress Oogenesis Pregnancy Sheep Spermatogenesis

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