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81.
The nineteenth century theologian, author and poet Charles Kingsley was a notable populariser of Darwinian evolution. He championed Darwin’s cause and that of honesty in science for more than a decade from 1859 to 1871. Kingsley’s interpretation of evolution shaped his theology, his politics and his views on race. The relationship between men and apes set the context for Kingsley’s consideration of these issues. Having defended Darwin for a decade in 1871 Kingsley was dismayed to read Darwin’s account of the evolution of morals in Descent of Man. He subsequently distanced himself from Darwin’s conclusions even though he remained an ardent evolutionist until his death in 1875.  相似文献   
82.
The development of molecular tools for the extraction, analysis and interpretation of DNA from the remains of ancient organisms (paleogenetics) has revolutionised a range of disciplines as diverse as the fields of human evolution, bioarchaeology, epidemiology, microbiology, taxonomy and population genetics. The paper draws attention to some of the challenges associated with the extraction and interpretation of ancient DNA from archaeological material, and then reviews the influence of paleogenetics on the field of human evolution. It discusses the main contributions of molecular studies to reconstructing the evolutionary and phylogenetic relationships between extinct hominins (human ancestors) and anatomically modern humans. It also explores the evidence for evolutionary changes in the genetic structure of anatomically modern humans in recent millennia. This breadth of research has led to discoveries that would never have been possible using traditional approaches to human evolution.  相似文献   
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84.
This study was designed to examine time-of-day effects on markers of cardiac functional capacity during a standard progressive cycle exercise test. Fourteen healthy, untrained young males (mean?±?SD: 17.9?±?0.7 yrs of age) performed identical maximal cycle tests in the morning (08:00-11:00?h) and late afternoon (16:00-19:00?h) in random order. Cardiac variables were measured at rest, submaximal exercise, and maximal exercise by standard echocardiographic techniques. No differences in morning and afternoon testing values at rest or during exercise were observed for oxygen uptake, heart rate, cardiac output, or markers of systolic and diastolic myocardial function. Values at peak exercise for Vo(2) at morning and afternoon testing were 3.20?±?0.49 and 3.24?±?0.55?L min(-1), respectively, for heart rate 190?±?11 and 188?±?15?bpm, and for cardiac output 19.5?±?2.8 and 19.8?±?3.5?L min(-1). Coefficients of variation for morning and afternoon values for these variables were similar to those previously published for test-retest reproducibility. This study failed to demonstrate evidence for significant time-of-day variation in Vo(2)max or cardiac function during standard progressive exercise testing in adolescent males.  相似文献   
85.
BackgroundThere are nationwide concerns about the unemployment rate among young Dutch cardiologists and the increase in temporary positions. Therefore, the aim of this study was to investigate the unemployment rate in this subgroup as well as the length of time between the end of their training and the acquisition of a permanent position.MethodsAll cardiologists who completed their training between January 2015 and December 2018 were invited to fill in an online questionnaire about their demographic characteristics, professional profile and employment status. The unemployment rate was calculated and Kaplan-Meier curves were used to determine the time between the end of training and the first permanent contract.ResultsIn total, 174 participants were included (mean age 35 ± 3 years, 64% male, median follow-up 2.3 years (interquartile range 1.4–3.2 years)). The unemployment rate was 0.6% (n = 1). Only 12 participants (7%) started their career with a permanent position. The percentage of cardiologists with a temporary position was 82%, 61% and 33% at 1, 2 and 3 years, respectively. The percentage of cardiologists with a temporary position did not differ with regard to age, gender, holding a PhD degree or type of teaching institution attended (academic vs non-academic). Forty-four per cent of participants perceived the current job market to be problematic.ConclusionsThe unemployment rate among young cardiologists in the Netherlands was low between 2015 and 2018. The vast majority of cardiologists start their career on a temporary contract. Three years later, 33% still hold temporary positions. Due to the resultant job insecurity, many young cardiologists describe the job market as problematic.  相似文献   
86.

Background

Healthy hearing depends on sensitive ears and adequate brain processing. Essential aspects of both hearing and cognition decline with advancing age, but it is largely unknown how one influences the other. The current standard measure of hearing, the pure-tone audiogram is not very cognitively demanding and does not predict well the most important yet challenging use of hearing, listening to speech in noisy environments. We analysed data from UK Biobank that asked 40–69 year olds about their hearing, and assessed their ability on tests of speech-in-noise hearing and cognition.

Methods and Findings

About half a million volunteers were recruited through NHS registers. Respondents completed ‘whole-body’ testing in purpose-designed, community-based test centres across the UK. Objective hearing (spoken digit recognition in noise) and cognitive (reasoning, memory, processing speed) data were analysed using logistic and multiple regression methods. Speech hearing in noise declined exponentially with age for both sexes from about 50 years, differing from previous audiogram data that showed a more linear decline from <40 years for men, and consistently less hearing loss for women. The decline in speech-in-noise hearing was especially dramatic among those with lower cognitive scores. Decreasing cognitive ability and increasing age were both independently associated with decreasing ability to hear speech-in-noise (0.70 and 0.89 dB, respectively) among the population studied. Men subjectively reported up to 60% higher rates of difficulty hearing than women. Workplace noise history associated with difficulty in both subjective hearing and objective speech hearing in noise. Leisure noise history was associated with subjective, but not with objective difficulty hearing.

Conclusions

Older people have declining cognitive processing ability associated with reduced ability to hear speech in noise, measured by recognition of recorded spoken digits. Subjective reports of hearing difficulty generally show a higher prevalence than objective measures, suggesting that current objective methods could be extended further.  相似文献   
87.
88.
Liu BA  Engelmann BW  Nash PD 《Proteomics》2012,12(10):1527-1546
Modular protein interaction domains (PIDs) that recognize linear peptide motifs are found in hundreds of proteins within the human genome. Some PIDs such as SH2, 14-3-3, Chromo, and Bromo domains serve to recognize posttranslational modification (PTM) of amino acids (such as phosphorylation, acetylation, methylation, etc.) and translate these into discrete cellular responses. Other modules such as SH3 and PSD-95/Discs-large/ZO-1 (PDZ) domains recognize linear peptide epitopes and serve to organize protein complexes based on localization and regions of elevated concentration. In both cases, the ability to nucleate-specific signaling complexes is in large part dependent on the selectivity of a given protein module for its cognate peptide ligand. High-throughput (HTP) analysis of peptide-binding domains by peptide or protein arrays, phage display, mass spectrometry, or other HTP techniques provides new insight into the potential protein-protein interactions prescribed by individual or even whole families of modules. Systems level analyses have also promoted a deeper understanding of the underlying principles that govern selective protein-protein interactions and how selectivity evolves. Lastly, there is a growing appreciation for the limitations and potential pitfalls associated with HTP analysis of protein-peptide interactomes. This review will examine some of the common approaches utilized for large-scale studies of PIDs and suggest a set of standards for the analysis and validation of datasets from large-scale studies of peptide-binding modules. We will also highlight how data from large-scale studies of modular interaction domain families can provide insight into systems level properties such as the linguistics of selective interactions.  相似文献   
89.
ABSTRACT: Specific peptide ligand recognition by modular interaction domains is essential for the fidelity of information flow through the signal transduction networks that control cell behavior in response to extrinsic and intrinsic stimuli. Src homology 2 (SH2) domains recognize distinct phosphotyrosine peptide motifs, but the specific sites that are phosphorylated and the complement of available SH2 domains varies considerably in individual cell types. Such differences are the basis for a wide range of available protein interaction microstates from which signaling can evolve in highly divergent ways. This underlying complexity suggests the need to broadly map the signaling potential of systems as a prerequisite for understanding signaling in specific cell types as well as various pathologies that involve signal transduction such as cancer, developmental defects and metabolic disorders. This report describes interactions between SH2 domains and potential binding partners that comprise initial signaling downstream of activated fibroblast growth factor (FGF), insulin (Ins), and insulin-like growth factor-1 (IGF-1) receptors. A panel of 50 SH2 domains screened against a set of 192 phosphotyrosine peptides defines an extensive potential interactome while demonstrating the selectivity of individual SH2 domains. The interactions described confirm virtually all previously reported associations while describing a large set of potential novel interactions that imply additional complexity in the signaling networks initiated from activated receptors. This study of pTyr ligand binding by SH2 domains provides valuable insight into the selectivity that underpins complex signaling networks that are assembled using modular protein interaction domains.  相似文献   
90.
Metabolic and ventilatory parameters were measured for the smallest and largest Isoodon bandicoots; the arid-adapted Barrow Island golden bandicoot (Isoodon auratus barrowensis) and the tropical northern brown bandicoot (Isoodon macrourus). I. a. barrowensis has a number of physiological characteristics that aid its tolerance of high Ta and survival in a hot and dry climate, including a low and labile body temperature, a very low basal metabolic rate, low total evaporative water loss, and an effective panting mechanism. I. macrourus generally has an “average” physiology for a bandicoot despite its size, although a number of its physiological characteristics aid survival in (sub)tropical conditions. These include a low body temperature, low total evaporative water loss and minute ventilation at high ambient temperatures, and an average thermal conductance. These data support the theory that phylogeny is a more important predictor of bandicoot physiology than habitat/distribution.  相似文献   
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