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1.
The ongoing coronavirus disease 2019 (COVID-19) crisis is having a large impact on acute and chronic cardiac care. Due to public health measures and t  相似文献   
2.

Purpose

To assess methods for determination of exercise intensity, and to investigate practice variation with respect to the contents, volume and intensity of exercise training programs in Dutch cardiac rehabilitation (CR) centres.

Methods

A paper questionnaire was sent to all Dutch CR centres, consisting of 85 questions for patients with an acute coronary syndrome (ACS) or after coronary revascularisation (Group 1) and for patients with chronic heart failure (CHF, Group 2).

Results

CR professionals from 45 centres completed the questionnaires (58 %). Symptom-limited exercise testing was used to determine exercise capacity in 76 % and 64 % of the CR centres in group 1 and group 2, respectively; in these centres, a percentage of the maximum heart rate was the most frequently used exercise parameter (65 % and 56 %, respectively). All CR centres applied aerobic training and the majority applied strength training (64 % in group 1 and 92 % in group 2, respectively). There was a considerable variation in training intensity for both aerobic and strength training, as well as in training volume (1–20 h and 1–18 h respectively).

Conclusion

Among Dutch CR centres, considerable variation exists in methods for determination of exercise intensity. In addition, there is no uniformity in training volume and intensity.  相似文献   
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4.
Properties of the echinoderm skeleton are under biological control, which is exerted in part by the organic matrix embedded in the mineralized part of the skeleton. This organic matrix consists of proteins and glycoproteins whose carbohydrate component is specifically involved in the control mechanisms. The saccharide moiety of the organic matrix of the spines of the echinoid Paracentrotus lividus was characterized using enzyme-linked lectin assays (ELLAs). O-glycoproteins, different types of complex N-glycoproteins, and terminal sialic acids were detected. Sialic acids are known to interact with Ca ions and could play an important role in the mineralization process. Some of the carbohydrate components detected by ELLAs as well as two organic matrix proteins (SM30 and SM50) were localized within different subregions of the spine skeleton using field-emission scanning electron microscopy. The mappings show that some of these components are not homogeneously distributed in the different skeletal subregions. For example, some N-glycoproteins were preferentially located in the putative amorphous subregion of the skeleton, whereas some O-glycoproteins were localized in the subregion where skeletal growth is inhibited. These results suggest that the biological control exerted on the skeletal properties can be partly modulated by local differences in the organic matrix composition.  相似文献   
5.
Coucke (1998) was the first to use acoustic resonance analysis to monitor embryo development in chicken eggs. He remarked that at around 100 hours of incubation, the course of the resonant frequency and damping changed abruptly in the case of fertile eggs. He also showed that these changes were related to a physiologic event during early embryonic development. The objective of our study is to monitor the course of the vibration parameters during the early incubation of chicken eggs and to relate these changes to egg and embryo characteristics. A total of 72 Hybro eggs were incubated vertically in a small incubator at standard conditions. Several egg parameters were measured before incubation. During the early stages of incubation the vibration behavior of these eggs was monitored. The time at which the damping of the vibration suddenly changed, the diameter of the eggs and their interaction were found to be significant explanatory variables in order to predict hatching time. A correlation coefficient r of 0.72 was obtained.  相似文献   
6.
During this work, it was investigated whether spectral measurements can be used to monitor embryonic growth. An experiment was conducted in which both the transmission spectra and embryonic weight were determined on 240 eggs (Cobb, 37 weeks) between Day 5 and Day 10 of incubation. The spectral data were linked to embryonic weight by means of a partial least squares analysis. Different preprocessing procedures were compared during this work, that is, smoothing, multiplicative scatter correction (MSC), and first‐ and second‐order derivative. Compared to the remainder of the preprocessing procedures, MSC leads to a considerable improvement of the prediction capability of the embryonic weight. The ratio of performance to deviation obtained for the MSC spectra equaled 4.5 indicating that a very accurate prediction of embryonic weight is feasible based on the VIS/NIR transmission measurements. Important regions for the prediction are situated around 685–740 nm. It is suggested that the spectral changes in these spectral regions result from the displacement of carotenoids from the yolk into the blood circuitry. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   
7.

Background

The objective of this study was to assess the effect of a web-based audit and feedback (A&F) intervention with outreach visits to support decision-making by multidisciplinary teams.

Methods

We performed a multicentre cluster-randomized trial within the field of comprehensive cardiac rehabilitation (CR) in the Netherlands. Our participants were multidisciplinary teams in Dutch CR centres who were enrolled in the study between July 2012 and December 2013 and received the intervention for at least 1 year. The intervention included web-based A&F with feedback on clinical performance, facilities for goal setting and action planning, and educational outreach visits. Teams were randomized either to receive feedback that was limited to psychosocial rehabilitation (study group A) or to physical rehabilitation (study group B). The main outcome measure was the difference in performance between study groups in 11 care processes and six patient outcomes, measured at patient level. Secondary outcomes included effects on guideline concordance for the four main CR therapies.

Results

Data from 18 centres (14,847 patients) were analysed, of which 12 centres (9353 patients) were assigned to group A and six (5494 patients) to group B. During the intervention, a total of 233 quality improvement goals was identified by participating teams, of which 49 (21%) were achieved during the study period. Except for a modest improvement in data completeness (4.5% improvement per year; 95% CI 0.65 to 8.36), we found no effect of our intervention on any of our primary or secondary outcome measures.

Conclusions

Within a multidisciplinary setting, our web-based A&F intervention engaged teams to define local performance improvement goals but failed to support them in actually completing the improvement actions that were needed to achieve those goals. Future research should focus on improving the actionability of feedback on clinical performance and on addressing the socio-technical perspective of the implementation process.

Trial registration

NTR3251
  相似文献   
8.

Background

Axonal injury after traumatic brain injury (TBI) may cause impaired sensory integration. We aim to determine the effects of childhood TBI on visual integration in relation to general neurocognitive functioning.

Methods

We compared children aged 6–13 diagnosed with TBI (n = 103; M = 1.7 years post-injury) to children with traumatic control (TC) injury (n = 44). Three TBI severity groups were distinguished: mild TBI without risk factors for complicated TBI (mildRF- TBI, n = 22), mild TBI with ≥1 risk factor (mildRF+ TBI, n = 46) or moderate/severe TBI (n = 35). An experimental paradigm measured speed and accuracy of goal-directed behavior depending on: (1) visual identification; (2) visual localization; or (3) both, measuring visual integration. Group-differences on reaction time (RT) or accuracy were tracked down to task strategy, visual processing efficiency and extra-decisional processes (e.g. response execution) using diffusion model analysis. General neurocognitive functioning was measured by a Wechsler Intelligence Scale short form.

Results

The TBI group had poorer accuracy of visual identification and visual integration than the TC group (Ps ≤ .03; ds ≤ -0.40). Analyses differentiating TBI severity revealed that visual identification accuracy was impaired in the moderate/severe TBI group (P = .05, d = -0.50) and that visual integration accuracy was impaired in the mildRF+ TBI group and moderate/severe TBI group (Ps < .02, ds ≤ -0.56). Diffusion model analyses tracked impaired visual integration accuracy down to lower visual integration efficiency in the mildRF+ TBI group and moderate/severe TBI group (Ps < .001, ds ≤ -0.73). Importantly, intelligence impairments observed in the TBI group (P = .009, d = -0.48) were statistically explained by visual integration efficiency (P = .002).

Conclusions

Children with mildRF+ TBI or moderate/severe TBI have impaired visual integration efficiency, which may contribute to poorer general neurocognitive functioning.  相似文献   
9.
BackgroundDespite proven clinical benefits, only a minority of patients complete outpatient cardiac rehabilitation (CR) after acute myocardial infarction (AMI). The main purpose of this study was to evaluate to what extent and at which time patients drop out of CR, and to assess which patient-related characteristics can predict dropout.MethodsIn a retrospective cohort study, we selected patients who had been hospitalised with an AMI in our centre in 2015 or 2016. Patients were selected pseudonymously based on reimbursement codes in the electronic health record. We extracted baseline characteristics and data on CR referral, enrolment and completion for each patient. Multivariable logistic regression was used to assess which characteristics predicted referral and dropout.ResultsThe 666 patients included were predominantly male (66%), with a mean age of 69.0 years. Of the 640 eligible patients, 201 (31%) were not referred for CR. Enrolment after referral was 94%. Nonreferral was independently associated with older age, female sex, traveling distance, non-ST-elevation myocardial infarction (NSTEMI; as compared with STEMI), no coronary revascularisation and prior manifestations of coronary artery disease. Of the 414 enrolled patients, 24% did not complete their CR programmes (i.e. dropped out). Older age and worse exercise capacity at baseline were independently associated with dropout. The ability of the multiple regression models to predict nonreferral and noncompletion was good to fair, with an area under the receiver operating characteristic curves of 0.86 and 0.71, respectively.ConclusionThe main reason for not participating in or not completing CR after AMI was nonreferral. To optimise CR utilisation, improvement of referral rates should be prioritised.  相似文献   
10.
The current diversity of life on earth is the product of macroevolutionary processes that have shaped the dynamics of diversification. Although the tempo of diversification has been studied extensively in macroorganisms, much less is known about the rates of diversification in the exceedingly diverse and species-rich microbiota. Decreases in diversification rates over time, a signature of explosive radiations, are commonly observed in plant and animal lineages. However, the few existing analyses of microbial lineages suggest that the tempo of diversification in prokaryotes may be fundamentally different. Here, we use multilocus and genomic sequence data to test hypotheses about the rate of diversification in a well-studied pathogenic bacterial lineage, Borrelia burgdorferi sensu lato (sl). Our analyses support the hypothesis that an explosive radiation of lineages occurred near the origin of the clade, followed by a sharp decay in diversification rates. These results suggest that explosive radiations may be a general feature of evolutionary history across the tree of life.  相似文献   
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