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Until now, biological invasions have been conceptualised and studied mainly as a linear process: from introduction to establishment to spread. This volume charts a new course for the field, drawing on key developments in network ecology and complexity science. It defines an agenda for Invasion Science 2.0 by providing new framings and classification of research topics and by offering tentative solutions to vexing problems. In particular, it conceptualises a transformative ecosystem as an open adaptive network with critical transitions and turnover, with resident species heuristically learning and fine-tuning their niches and roles in a multiplayer eco-evolutionary game. It erects signposts pertaining to network interactions, structures, stability, dynamics, scaling, and invasibility. It is not a recipe book or a road map, but an atlas of possibilities: a 'hitchhiker's guide'.
This lucid, accessible introduction to supervised machine learning presents core concepts in a focused and logical way that is easy for beginners to follow. The author assumes basic calculus, linear algebra, probability and statistics but no prior exposure to machine learning. Coverage includes widely used traditional methods such as SVMs, boosted trees, HMMs, and LDAs, plus popular deep learning methods such as convolution neural nets, attention, transformers, and GANs. Organized in a coherent presentation framework that emphasizes the big picture, the text introduces each method clearly and concisely “from scratch” based on the fundamentals. All methods and algorithms are described by a clean and consistent style, with a minimum of unnecessary detail. Numerous case studies and concrete examples demonstrate how the methods can be applied in a variety of contexts.
This is the first book-length treatment of the regulation of financial technology (Fintech) in China. Fintech brings about paradigm changes to the traditional financial system, presenting both challenges and opportunities. At the international level, there has been a fierce competition for the coveted title of global Fintech hub. One of the key enablers of success in this race is regulation. As the world's leader in Fintech, China's regulatory experience is of both academic and practical significance. This book presents a systematic and contextualized account of China's Fintech regulation, and in doing so, tries to identify and analyze relevant institutional factors contributing to the development of the Chinese law. It also takes a comparative approach to critically evaluating the Chinese experience. The book illustrates why and how China's Fintech regulation has been developed, if and how it differs from the rest of the world, and what can be learned from the Chinese experience.
Despite some policy gains and expanded civil liberties, sexual minorities in South Korea face challenges from both conservatives and liberals. While anti-LGBTI conservatives seek to block equal rights and antidiscrimination laws, many liberal politicians have been reluctant to embrace sexual minority rights as fundamental human rights. In many instances, they portray sexual minority rights as premature, rather than permanently impossible, asserting that it is “not yet” the right time in Korea. This chapter discusses early LGBTI mobilization in the 1990s in three parts: the solidarity politics cultivated with labor and emerging human rights activism against state violence and national security surveillance; the untimely deaths of LGBTI activists; and so-called youth protection policies that deferred freedom and empowerment for LGBTI youth. This discussion is paired with an analysis of how LGBTI rights activism fared during and after the Candlelight Protests in 2016–17 in what I call a “politics of postponement.”
Saetaspongia so far cannot be confidently assigned to any class-level crown group. Clarifying its phylogenetic position requires new information provided by more detailed studies of previously described and/or new material. Some sponge fossils with the typical skeletal architecture of Saetaspongia have recently been recognized in the Cambrian (Stage 4) Balang Biota of Guizhou, China, including S. jianhensis new species and S. cf. S. densa. The new taxon is characterized by the following features: spicules are fine monaxons and are inclined to be loosely to densely arranged into plumose arrays; skeleton is composed primarily of one major plumose bundle, with an uncertain number (perhaps two) of small plumose arrays; and primary skeleton is occasionally interspersed with some irregularly oriented individual spicules. An additional specimen consisting of large monaxons, with plumose structures and overlying irregular coarse monaxons, closely fits the description and illustrations of previously described S. cf. S. densa. By combining information from previous studies and the present research, fossil evidence indicates that the plumose architecture is a critical feature diagnostic of Saetaspongia and that there are no hexactine-based spicules in this genus. The new material from the Balang Biota further supports the notion that Saetaspongia has a protomonaxonid rather than a hexactinellid affinity. Fossil evidence suggests that Saetaspongia had a wide biogeographic distribution during the early Cambrian and the stratigraphic distribution of this genus extends up to Stage 4.
To identify error-prone operational steps and key sites of self-contamination during donning and doffing of personal protective equipment (PPE).
A total of 56 health care workers including 37 nurses and 19 physicians, were recruited to don and doff the PPE recommended by the Chinese Center for Disease Control and Prevention. Operational errors and sites of self-contamination were recorded using UV-fluorescent labeling and video surveillance.
Three main errors during donning were identified: choosing a loose-fitting coverall that was difficult to handle; ignoring to inspect the seal of N95 respirator or gloves; and forgetting to pull up the zipper completely. Four main errors during doffing were identified: removing the N95 respirator in a wrong way; touching the scrubs with contaminated hands and elbows; touching contaminated external surfaces of the goggles; and performing insufficient hand hygiene. Key sites that were easily contaminated during the doffing of PPE included left hand and wrist, left lower leg, chest, and left abdomen.
Identifying the steps prone to errors and key sites of self-contamination in the process of PPE donning and doffing can facilitate the training of PPE use and provide detailed evidence for optimizing standardized protocols to reduce contamination.
Bioarchaeological research provides unique insights on human adaptation, diet, lifestyle and epidemiology. The Mogou Bioarchaeology Project explores how health was affected by the Bronze Age transition in north-west China. Preliminary results reveal that the inhabitants experienced substantial physiological stress, infectious disease and lethal trauma.
X-ray powder diffraction data, unit-cell parameters, and space group for N,N-dimethyl-1H-benzo[d]imidazol-2-amine, C9H11N3, are reported [a = 11.379(3) Å, b = 10.227(5) Å, c = 7.151(1) Å, α = 90°, β = 90°, γ = 90°, unit-cell volume V = 832.318 Å3, Z = 4, ρcal = 1.286 g cm−3, and space group P21212]. All measured lines were indexed and were consistent with the P21212 space group. No detectable impurities were observed.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is pandemic. Prevention and control strategies require an improved understanding of SARS-CoV-2 dynamics. We did a rapid review of the literature on SARS-CoV-2 viral dynamics with a focus on infective dose. We sought comparisons of SARS-CoV-2 with other respiratory viruses including SARS-CoV-1 and Middle East respiratory syndrome coronavirus. We examined laboratory animal and human studies. The literature on infective dose, transmission and routes of exposure was limited specially in humans, and varying endpoints were used for measurement of infection. Despite variability in animal studies, there was some evidence that increased dose at exposure correlated with higher viral load clinically, and severe symptoms. Higher viral load measures did not reflect coronavirus disease 2019 severity. Aerosol transmission seemed to raise the risk of more severe respiratory complications in animals. An accurate quantitative estimate of the infective dose of SARS-CoV-2 in humans is not currently feasible and needs further research. Our review suggests that it is small, perhaps about 100 particles. Further work is also required on the relationship between routes of transmission, infective dose, co-infection and outcomes.
There has been growing interest in understanding the life-span development of creativity (Hui, He, and Wong, 2019). Throughout the life course, creativity grows and declines and serves different purposes for different individuals, making creativity development a dynamic process. For example, a preschooler displays imagination by making up songs with interesting rhymes for self-expression. A school-age child develops a keen interest, out of curiosity, in digging deeper into topics such as planetology or paleontology. An adolescent experiments with new ideas in the pursuit of personal expression. A young adult shows independence in choosing his or her career to form a new identity. An established design engineer and his or her team create a new product to make a financial profit or to effect a social impact. An older adult engages in creative narrative expression to reinterpret the meaning of his or her life. Creativity is defined as novel and appropriate behaviors and within a continuum of impact in a field (Sternberg and Lubart, 1999; Piffer, 2012). Creativity engenders society’s greatest achievements, business innovations, and personal . This chapter takes the perspective of to study the emergence of and changes in creative attitude, behaviors, and experiences in terms of nurturing potential and growth and of exploring the limits and decline of creativity through both the and the . The life-span developmental model of creativity postulates that the types of creativity expressed, how they are measured, and how they are valued vary in different life stages from childhood and adolescence to adulthood and late adulthood. Empirical evidence on the significant factors for the development of creativity across the life-span is also reviewed with reference to the critical issues in each life stage. The discussion also includes educational and practical implications as well as future research directions on creativity research.
Individuals with HIV are at increased risk for osteoporosis. A healthy diet with adequate calcium is recommended to promote bone health. However, lengthy nutritional assessments pose barriers to routine screenings in clinical practice. This study aimed to examine the validity and reproducibility of a six-item dietary calcium screening tool among Chinese individuals with HIV.
We conducted a two time-point study in an outpatient setting. Volunteers self-administered the six-item tool upon enrollment and again at one-month follow-up. At baseline, participants also completed a validated food frequency questionnaire and surveys regarding demographic and clinical risk factors.
Beijing, China; Shenzhen, Guangdong, China
Upon enrollment, 127 individuals with HIV participated in the study, of whom 83 completed the follow-up screening.
Mean age of participants was 35.2±9.3 years, average BMI was 22.8±3.8 kg/m2, and 89% were men. Among the participants, 54.7% reported calcium intake less than 800 mg/day. The six-item tool demonstrated fair-to-moderate relative validity with a correlation of 0.39 and 75.7% of subjects classified in same/adjacent quartiles as the reference, and moderate-to-good reproducibility with a correlation of 0.60 and 83.1% of subjects classified in same/adjacent quartiles. Finally, ROC analyses yielded a sensitivity of 87.0% and a specificity of 39.4% with optimized cut-off level.
The six-item tool presented adequate validity and reproducibility to identify individuals with low calcium intake among the target population, providing a convenient instrument for categorizing calcium intake in clinical practice, prompting referrals for further assessment, and raising awareness of dietary calcium in bone disease prevention.
Late Mesozoic igneous rocks are important for deciphering the Mesozoic tectonic setting of NE China. In this paper, we present whole-rock geochemical data, zircon U–Pb ages and Lu–Hf isotope data for Early Cretaceous volcanic rocks from the Tulihe area of the northern Great Xing’an Range (GXR), with the aim of evaluating the petrogenesis and genetic relationships of these rocks, inferring crust–mantle interactions and better constraining extension-related geodynamic processes in the GXR. Zircon U–Pb ages indicate that the rhyolites and trachytic volcanic rocks formed during late Early Cretaceous time (c. 130–126 Ma). Geochemically, the highly fractionated I-type rhyolites exhibit high-K calc-alkaline, metaluminous to weakly peraluminous characteristics. They are enriched in light rare earth elements (LREEs) and large-ion lithophile elements (LILEs) but depleted in high-field-strength elements (HFSEs), with their magmatic zircons ϵHf(t) values ranging from +4.1 to +9.0. These features suggest that the rhyolites were derived from the partial melting of a dominantly juvenile, K-rich basaltic lower crust. The trachytic volcanic rocks are high-K calc-alkaline series and exhibit metaluminous characteristics. They have a wide range of zircon ϵHf(t) values (−17.8 to +12.9), indicating that these trachytic volcanic rocks originated from a dominantly lithospheric-mantle source with the involvement of asthenospheric mantle materials, and subsequently underwent extensive assimilation and fractional crystallization processes. Combining our results and the spatiotemporal migration of the late Early Cretaceous magmatic events, we propose that intense Early Cretaceous crust–mantle interaction took place within the northern GXR, and possibly the whole of NE China, and that it was related to the upwelling of asthenospheric mantle induced by rollback of the Palaeo-Pacific flat-subducting slab.
Schools offer an ideal setting for childhood obesity interventions due to their access to children and adolescents. This review aimed to systematically review the impact of school-based intervention for the treatment of childhood obesity.
Eight databases were searched from inception till 30 May 2020. A revised Cochrane risk-of-bias tool and the Grading of Recommendations, Assessment, Development and Evaluations criteria were used to evaluate the risk of bias and overall evidence. Meta-analysis and meta-regression were performed on Stata software using the random effects model. Overall effect was evaluated using Hedges’ g, and heterogeneity was assessed using Cochran’s Q and I2.
Cluster randomised controlled trials (cluster-RCT) delivered in school.
Children and adolescents (6–18 years of age) with overweight and obesity.
Twelve cluster-RCT from seven countries with 1755 participants were included in the meta-analysis. School-based interventions for the treatment of childhood obesity reduced BMI and BMI z-scores with a medium effect (g = 0·52). Subgroup analyses showed greater effectiveness of brief school-based interventions and the interventions conducted in lower-middle to upper-middle economies. Meta-regression assessed the heterogeneity and the final model, with covariates of the type of economies and trial duration, accounted for 41·2 % of the variability. The overall quality of evidence was rated low because of the high risk of bias and inconsistency.
School-based interventions are a possible approach to provide universal healthcare for the treatment of childhood obesity, and further well-designed cluster-RCT with longer follow-up are needed. This study is registered with PROSPERO (CRD42020160735).
Evidence about the impact of the COVID-19 pandemic on the mental health of specific subpopulations, such as university students, is needed as communities prepare for future waves.
To study the association of proximity of COVID-19 with symptoms of anxiety and depression in university students.
This trend study analysed weekly cross-sectional surveys of probabilistic samples of students from the University of British Columbia for 13 weeks, through the first wave of COVID-19. The main variable assessed was propinquity of COVID-19, defined as ‘knowing someone who tested positive for COVID-19’, which was specified at different levels: knowing someone anywhere globally, in Canada, in Vancouver, in their course or at home. Proximity was included in multivariable linear regressions to assess its association with primary outcomes, including 30-day symptoms of anxiety and/or depression.
Of 1388 respondents (adjusted response rate of 50%), 5.6% knew someone with COVID-19 in Vancouver, 0.8% in their course and 0.3% at home. Ten percent were overwhelmed and unable to access help. Knowing someone in Vancouver was associated with an 11-percentage-point increase in the probability of 30-day anxiety symptoms (s.e. 0.05, P ≤ 0.05), moderated by gender, with a significant interaction of the exposure and being female (coefficient −20, s.e. 0.09, P ≤ 0.05). No association was found with depressive symptoms.
Propinquity of COVID-19 cases may increase the likelihood of anxiety symptoms in students, particularly among men. Most students reported coping well, but additional support is needed for an emotionally overwhelmed minority who report being unable to access help.
Precise auditory perception at a subcortical level (neural representation and encoding of sound) has been suggested as a form of implicit L2 aptitude in naturalistic settings. Emerging evidence suggests that such implicit aptitude explains some variance in L2 speech perception and production among adult learners with different first language backgrounds and immersion experience. By examining 46 Chinese learners of English, the current study longitudinally investigated the extent to which explicit and implicit auditory processing ability could predict L2 segmental and prosody acquisition over a 5-month early immersion. According to the results, participants’ L2 gains were associated with more explicit and integrative auditory processing ability (remembering and reproducing music sequences), while the role of implicit, preconscious perception appeared to be negligible at the initial stage of postpubertal L2 speech learning.
Psychophysics as Mach understood it could be explained in several ways. This reflects the central conundrum that psychophysics held the potential to resolve: the communication of an individual’s subjective experience. This chapter surveys the many ways in which Mach described psychophysical experiences, from demonstrations on his Bösendorfer grand piano to differential equations. These descriptions were often multi-modal, using sound and images in tandem. Mach also employed analogies, mathematical derivations, and descriptions of the subjective experience of such phenomena as accommodation, acceleration, and visual after-images. A comparison of how Mach discusses psychophysics in popular lectures, scientific publications, and personal correspondence suggests that he made a number of assumptions about how best to communicate scientific ideas to different audiences. Further, this chapter argues that Mach’s techniques of presentation/argumentation, celebrated both in his time and subsequently, went far towards cultivating a psychophysical imaginarium similar to a mind’s eye. That is, by asking his readers or listeners to imagine specific psychophysical experiences, Mach established the broad outlines of a new way of thinking about subjectivity.
Seaweeds have numerous biologically active ingredients, such as polysaccharides, polyphenols and carotenoids, that are beneficial to human health. Although these benefits might be related to the synthesis, secretion or reabsorption of uric acid, no studies have explored the relationship between seaweeds consumption and hyperuricaemia (HUA) in the general population. The aim of this study was to investigate whether seaweeds consumption is related to HUA in a large-scale adult population. A cross-sectional study was conducted with 32 365 adults (17 328 men and 15 037 women) in Tianjin, People’s Republic of China. Frequency of seaweeds consumption was assessed by a validated self-administered FFQ. HUA was defined as serum uric acid levels >420 μmol/L in men and >350 μmol/L in women. The association between seaweeds consumption and HUA was assessed by multiple logistic regression analysis. Restricted cubic spline functions were used for non-linearity tests. The prevalence of HUA in men and women was 21·17 % and 5·93 %, respectively. After adjustments for potential confounding factors, the OR (95 % CI) for HUA across seaweed consumption (g/1000 kcal per d) were 1·00 (reference) for level 1, 0·91 (95 % CI 0·81, 1·02) for level 2; 0·90 (95 % CI 0·81, 1·01) for level 3; 0·86 (95 % CI 0·78, 0·97) for level 4 in men and 0·90 (95 % CI 0·73, 1·10) for level 2; 0·82 (95 % CI 0·67, 1·00) for level 3; 0·84 (95 % CI 0·68, 1·03) for level 4 in women, respectively. A negative correlation between seaweeds consumption and HUA in males but not in females was observed. Further studies are needed to explore the causal relationship.
Dying is mostly seen as a dreadful event, never a happy experience. Yet, as palliative care physicians, we have seen so many patients who remained happy despite facing death. Hence, we conducted this qualitative study to explore happiness in palliative care patients at the University of Malaya Medical Centre.
Twenty terminally ill patients were interviewed with semi-structured questions. The results were thematically analyzed.
Eight themes were generated: the meaning of happiness, connections, mindset, pleasure, health, faith, wealth, and work. Our results showed that happiness is possible at the end of life. Happiness can coexist with pain and suffering. Social connections were the most important element of happiness at the end of life. Wealth and work were given the least emphasis. From the descriptions of our patients, we recognized a tendency for the degree of importance to shift from the hedonic happiness to eudaimonic happiness as patients experienced a terminal illness.
Significance of results
To increase the happiness of palliative care patients, it is crucial to assess the meaning of happiness for each patient and the degree of importance for each happiness domain to allow targeted interventions.
Real-life decisions are often complex because they involve making sequential choices that constrain future options. We have previously shown that to render such multi-step decisions manageable, people ‘prune’ (i.e. selectively disregard) branches of decision trees that contain negative outcomes. We have theorized that sub-optimal pruning contributes to depression by promoting an oversampling of branches that result in unsavoury outcomes, which results in a negatively-biased valuation of the world. However, no study has tested this theory in depressed individuals.
Thirty unmedicated depressed and 31 healthy participants were administered a sequential reinforcement-based decision-making task to determine pruning behaviours, and completed measures of depression and anxiety. Computational, Bayesian and frequentist analyses examined group differences in task performance and relationships between pruning and depressive symptoms.
Consistent with prior findings, participants robustly pruned branches of decision trees that began with large losses, regardless of the potential utility of those branches. However, there was no group difference in pruning behaviours. Further, there was no relationship between pruning and levels of depression/anxiety.
We found no evidence that sub-optimal pruning is evident in depression. Future research could determine whether maladaptive pruning behaviours are observable in specific sub-groups of depressed patients (e.g. in treatment-resistant individuals), or whether misuse of other heuristics may contribute to depression.
To investigate the clinical impact of ventilator-associated events (VAEs) on adverse prognoses and risk factors for mortality among intensive care unit (ICU) patients receiving invasive mechanical ventilation (IMV) based on an ICU healthcare-associated infection (ICU-HAI) registry.
A cohort study was conducted based on an ICU-HAI registry including 30,830 patients between 2015 and 2018.
The study was conducted using data from 5 adult ICUs of a referral hospital.
Adult patients in the ICU-HAI registry who received ≥4 consecutive IMV days.
Clinical outcomes and mortality risk factors for VAEs were analyzed using propensity score matching (PSM), multivariate regression models, and sensitivity analyses.
Of 6,426 included patients, 1,803 developed 1,899 VAEs. After PSM, patients with VAEs did have prolonged length of stay in the ICU and in the hospital, increased hospitalization costs, longer days on mechanical ventilation, higher proportion of ≥9 days on mechanical ventilation, higher rate of failure in extubating mechanical ventilation, and excess all-cause mortality in the ICU. Older age (adjusted OR [aOR], 1.02), higher APACHE II score on ICU admission (aOR, 1.06), pneumonia (aOR, 1.49), blood transfusion (aOR 1.43), immunosuppressive drugs (aOR, 1.69), central-line catheter (aOR, 2.06), and ≥2 VAEs in the ICU (aOR, 1.99) were associated with higher risks for all-cause mortality in an ICU.
Patients with VAEs indeed had poorer clinical outcomes. Older age, higher APACHE II score on ICU admission, pneumonia, blood transfusion, immunosuppressive drugs, central-line catheter, and ≥2 VAEs in the ICU were risk factors for all-cause mortality of VAE patients in the ICU.