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51.
Riflemen/tītipounamu (Acanthisitta chloris) are kin-based cooperatively breeding birds, which appear able to recognise their relatives. Here, we investigate the potential for vocalisations to act as recognition cues in riflemen. We identified an appropriate contact call and recorded it at the nest from 19 adult riflemen. Measurements of call characteristics were individually repeatable. In addition, call similarity was significantly correlated with relatedness among all birds and among males. Thus, in principle, these contact calls contain sufficient information for individual recognition of familiar kin, and some assessment of relatedness between unfamiliar birds. To test whether riflemen responded differently to calls of kin, we broadcast calls of relatives and non-relatives as separate treatments in a playback experiment. Focal birds rarely responded aggressively or affiliatively, and their tendency to do so was unrelated to treatment. We conclude that zip calls are suitable kin recognition cues, but whether they are used as such remains unknown.  相似文献   
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Abstract

Longevity and other life history variables are key to understanding evolutionary processes and the biology of extinct animals. For the past 20 years, the lifespan of cave bears received an increased interest. Studies focusing on incremental lines of tooth cementum resulted in detailed mortality patterns from different localities. In this review, we summarise literature on age estimation as well as mortality of different European cave bear localities and present novel data on longevity from 94 teeth originating from 20 European localities. Additionally, the relative tooth emergence pattern of the permanent dentition is investigated under the Schultz’s rule framework of possible life history implications. For this, the known sequences of extant bear species are compared with the one of cave bears. Our results suggest that the typical duration of the life of cave bears was 19 years but data from literature show that in rare cases ages of up to 30–32 years were achieved. Additionally, we present the oldest known age for the Middle Pleistocene cave bear Ursus deningeri, 29 years. The tooth eruption pattern of cave bears exhibits a heterochronic shift that implies, under the assumption of Schulz’ rule, a slightly faster life history than closely related species.  相似文献   
53.
Crop rotation systems in organic and conventional farming systems differ in crop types, management and duration. However, changes in arthropod communities over the entire rotation system are poorly understood, as many studies have surveyed only single years or have not covered the entire rotation period. Here, we describe changes in arthropods in two contrasting systems at a split organic‐conventional farm: an 8‐year organically managed rotation with five crops and a 5‐year conventionally managed rotation with three crops. Arthropods were classified into three functional groups, representing epigeal predators, foliar predators/parasitoids and herbivores/pollinators. Epigeal predators were particularly reduced by soil tillage which occurred annually in the conventional rotation, but was intermittent in the organic. Arthropods were most abundant on the conventional rotation, but most taxonomically diverse on the organic. In the conventional system, all functional groups showed a cyclical change in their taxonomic composition that closely matched the crop rotation sequence, whereas in the organic rotation, the cycle was less clear. Whilst the current year's crop type was the major determinant of arthropod community composition, there was a significant “lag effect” for many taxa from the preceding year's crop. Our results suggest that both the amounts of soil tillage (e.g., in no‐till systems) and crop rotation order have major impacts on arthropods in agroecosystems. Rotations with excessive soil tillage are likely to reduce the abundance of some groups of beneficial arthropods, especially epigeal predators.  相似文献   
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Background:Optimizing the approach to and consent of potential organ donors maximizes patient autonomy and the availability of organs for transplants. We set out to identify modifiable factors associated with donation consent.Methods:We conducted a retrospective cohort study of consecutive adults (≥ 18 yr) referred for organ donation in Ontario between April 2013 and June 2019. We analyzed patient clinical data and demographics, data on substitute decision-makers and characteristics of the donation consent approach. Study outcomes were consent for organ donation and approach rate. We evaluated independent associations between consent and approach-and system-level factors.Results:We identified 34 837 referrals for organ donation, of which 6548 (18.8%) substitute decision-makers were approached for consent. Of these, 3927 (60.0% of approaches) consented for organ donation and 1883 (48.0% of consents) patients proceeded to be organ donors. The most common reason substitute decision-makers were not approached for consent in a case with donation potential was a late referral by the health care team (45.2%). Modifiable factors independently associated with consent included a telephone approach for consent (adjusted odds ratio [OR] 0.46, 95% confidence interval [CI] 0.35–0.58) and a collaborative approach by a physician and donation coordinator (adjusted OR 1.26, 95% CI 1.01–1.59).Interpretation:Consent for organ donation was associated with several modifiable factors. Organizations should target interventions to ensure timely referrals to organ donation organizations, increase in-person consent approaches and increase physician participation in the approach process.

Many people die on transplant waiting lists because the demand for organs outstrips supply. Almost 4500 people are on organ transplant waiting lists in Canada. Despite public support for organ donation across Canada,1 donation rates vary between 8.8 and 21.2 donors per million population, 2 and a substantial pool of potential donors is not being realized. 2,3 The identification, referral and approach of potential donors can be facilitated by policy, legislation and best practices, 3,4 although the efficacy of interventions is variable across jurisdictions.5,6 Some comprehensive interventions to increase donor numbers have not changed consent rates,7 suggesting that the consent approach process may be a target for improvement.Substitute decision-makers play an important role in the organ donation process, even in jurisdictions with donation consent registries or opt-out consent systems. Substitute decision-makers are almost always asked permission for organ donation, even when there is a registered donation consent,8 and their consent rates vary widely.9 Substitute decision-makers faced with consent decisions often do so in emotionally charged circumstances, and many do not know the explicit wishes of the patient.10 Given this context, the process of obtaining consent and the supports provided may have a substantial impact on the decision. Practices have been identified that improve consent rates from substitute decision-makers,11 and these are routinely performed by large, high-performing organ donation organizations. Several epidemiological studies have identified nonmodifiable factors associated with donation consent (e.g., race, age, socioeconomic status and education).1215 The persistent variability in consent rates suggests that other modifiable factors may influence a substitute decision-maker’s decision to consent.We aimed to identify modifiable approach-and system-level factors that were associated with positive consent for organ donation in Ontario, Canada.  相似文献   
56.
In dynamic environments, it is crucial to accurately consider the timing of information. For instance, during saccades the eyes rotate so fast that even small temporal errors in relating retinal stimulation by flashed stimuli to extra-retinal information about the eyes’ orientations will give rise to substantial errors in where the stimuli are judged to be. If spatial localization involves judging the eyes’ orientations at the estimated time of the flash, we should be able to manipulate the pattern of mislocalization by altering the estimated time of the flash. We reasoned that if we presented a relevant flash within a short rapid sequence of irrelevant flashes, participants’ estimates of when the relevant flash was presented might be shifted towards the centre of the sequence. In a first experiment, we presented five bars at different positions around the time of a saccade. Four of the bars were black. Either the second or the fourth bar in the sequence was red. The task was to localize the red bar. We found that when the red bar was presented second in the sequence, it was judged to be further in the direction of the saccade than when it was presented fourth in the sequence. Could this be because the red bar was processed faster when more black bars preceded it? In a second experiment, a red bar was either presented alone or followed by two black bars. When two black bars followed it, it was judged to be further in the direction of the saccade. We conclude that the spatial localization of flashed stimuli involves judging the eye orientation at the estimated time of the flash.  相似文献   
57.
Northern wetlands make up a substantial terrestrial carbon sink and are often dominated by decay-resistant Sphagnum mosses. Recent studies have shown that planctomycetes appear to be involved in degradation of Sphagnum-derived debris. Novel trimethylornithine (TMO) lipids have recently been characterized as abundant lipids in various Sphagnum wetland planctomycete isolates, but their occurrence in the environment has not yet been confirmed. We applied a combined intact polar lipid (IPL) and molecular analysis of peat cores collected from two northern wetlands (Saxnäs Mosse [Sweden] and Obukhovskoye [Russia]) in order to investigate the preferred niche and abundance of TMO-producing planctomycetes. TMOs were present throughout the profiles of Sphagnum bogs, but their concentration peaked at the oxic/anoxic interface, which coincided with a maximum abundance of planctomycete-specific 16S rRNA gene sequences. The sequences detected at the oxic/anoxic interface were affiliated with the Isosphaera group, while sequences present in the anoxic peat layers were related to an uncultured planctomycete group. Pyrosequencing-based analysis identified Planctomycetes as the major bacterial group at the oxic/anoxic interface at the Obukhovskoye peat (54% of total 16S rRNA gene sequence reads), followed by Acidobacteria (19% reads), while in the Saxnäs Mosse peat, Acidobacteria were dominant (46%), and Planctomycetes contributed to 6% of the total reads. The detection of abundant TMO lipids in planctomycetes isolated from peat bogs and the lack of TMO production by cultures of acidobacteria suggest that planctomycetes are the producers of TMOs in peat bogs. The higher accumulation of TMOs at the oxic/anoxic interface and the change in the planctomycete community with depth suggest that these IPLs could be synthesized as a response to changing redox conditions at the oxic/anoxic interface.  相似文献   
58.
Septins are a family of GTP-binding cytoskeleton proteins expressed in many solid tumors. Septin 9 (SEPT9) in particular was found overexpressed in diverse carcinomas. Herein, we studied the expression of SEPT9 isoform 1 protein (SEPT9_i1) in human prostate cancer specimens. We utilized immunohistochemical staining to study the expression of SEPT9_i1 protein. Staining level was analyzed in association with clinical characteristics and the pathological Gleason grade and score. Fifty human prostate cancer specimens (42 primary tumors and 8 metastatic lesions) were stained by SEPT9_i1 antibody and analyzed. SEPT9_i1 protein was expressed in prostate cancer cells but absent in normal epithelial cells. The intensity of staining was correlated proportionally to pretreatment prostate-specific antigen (PSA) blood levels and Gleason score (P < 0.05). SEPT9_i1 was highly expressed in all metastatic lesions. A significant assocation between SEPT9_i1 expression and high Gleason score on multivariate linear regression analysis was found. We conclude that SEPT9_i1 is expressed in high-grade prostate tumors suggesting it has a significant role in prostate tumorigenesis and that it could serve as a molecular marker for prostate tumor progression.  相似文献   
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