scholarly journals The effects of sampling strategy on the quality of reconstruction of viral population dynamics using Bayesian skyline family coalescent methods: A simulation study

2016 ◽  
Vol 2 (1) ◽  
Author(s):  
Matthew D. Hall ◽  
Mark E. J. Woolhouse ◽  
Andrew Rambaut
Author(s):  
Ola Pasternak

Recently, the analysis of haplotypes has garnered a lot of attention in both popular media, from companies such as 23andMe, and in scientific journal publications. Haplotypes, which can be thought of as DNA patterns in the chromosome, may remain unchanged for centuries and are therefore a promising new method for tracing lineages. This method could provide valuable new insights into population dynamics, specifically regarding ancient populations. However, a crucial issue is that historians are not trained to evaluate this sort of evidence, yet many publications in prestigious journals such as Nature and Science are making historical claims based on haplotype analysis. When analyzing this data, a few key assumptions must be made. Of particular concern are logical circularities in hypothesis generation and in sampling strategy. This is to say, that the hypotheses are often not based on "scientific" data, but are instead drawn from often outdated historical assumptions. These same assumptions then drive a sampling strategy that guide the study to a conclusion in line with the hypothesis. What is the professional historian to do? Proposed is a common-sense user guide for a non-specialist to evaluate the quality of the data and claims made with it. Several case studies will be examined from this perspective that show both the strengths and weaknesses of this new source of historical and archaeological evidence.


1992 ◽  
Vol 25 (4-5) ◽  
pp. 399-400 ◽  
Author(s):  
L. Cingolani ◽  
M. Cossignani ◽  
R. Miliani

Statistical analyses were applied to data from a series of 38 samples collected in an aerobic treatment plant from November 1989 to December 1990. Relationships between microfauna structure and plant operating conditions were found. Amount and quality of microfauna groups and species found in activated sludge proved useful to suggest the possible causes of disfunctions.


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 726-727
Author(s):  
Diana White ◽  
Tunalilar Ozcan ◽  
Serena Hasworth ◽  
Jaclyn Winfree

Abstract Quality is defined in multiple ways and by different stakeholders (e.g., residents, regulators, informed observers). Using a two-stage stratified sampling strategy, we collected data from N=241 residents living in 31 assisted living and residential care communities (AL/RC) in Oregon. Residents rated their overall satisfaction and satisfaction with the AL/RC as a place to live and to receive care. Each interviewer completed a facility profile summarizing their observations about the setting, including quality of staff-resident interactions and physical environment. Residents and interviewers were also asked whether they would recommend the community to others. Finally, we used deficiency citations given during regular inspections by the licensing agency to proxy regulatory perspective. Results show that perceived quality varied by stakeholder (e.g., residents’ assessments differed from deficiency citations). Given this variation, findings suggest that efforts to make quality indicators publicly available should include multiple measures and perspectives, especially residents.


2021 ◽  
Vol 10 (2) ◽  
pp. 289 ◽  
Author(s):  
Maria Stella Epifanio ◽  
Federica Andrei ◽  
Giacomo Mancini ◽  
Francesca Agostini ◽  
Marco Andrea Piombo ◽  
...  

The COVID-19 pandemic that has hit the world in the year 2020 has put a strain on our ability to cope with events and revolutionized our daily habits. On 9 March, Italy was forced to lockdown to prevent the spread of the infection, with measures including the mandatory closure of schools and nonessential activities, travel restrictions, and the obligation to spend entire weeks in the same physical space. The aim of this study was to assess the impact of the COVID-19 pandemic and lockdown measures on quality of life (QoL) in a large Italian sample, in order to investigate possible differences in QoL levels related to both demographic and pandemic-specific variables. A total of 2251 Italian adults (1665 women, mainly young and middle adults) were recruited via a snowball sampling strategy. Participants were requested to answer to an online survey, which included demographic and COVID-related information items, and the World Health Organization Quality of Life BREF questionnaire (WHOQOL-BREF). The results showed statistically significant differences in QoL depending on a number of variables, including sex, area of residence in Italy, and being diagnosed with a medical/psychiatric condition. To our knowledge, this is the first study to assess QoL during COVID-19 pandemic in Italy, therefore the present findings can offer guidelines regarding which social groups are more vulnerable of a decline in QoL and would benefit of psychological interventions.


2014 ◽  
Vol 536-537 ◽  
pp. 1431-1434 ◽  
Author(s):  
Ying Zhu ◽  
Yin Cheng Zhang ◽  
Shun He Qi ◽  
Zhi Xiang

Based on the molecular dynamics (MD) theory, in this article, we made a simulation study on titanium nanometric cutting process at different cutting depths, and analyzed the changes of the cutting depth to the effects on the work piece morphology, system potential energy, cutting force and work piece temperature in this titanium nanometric cutting process. The results show that with the increase of the cutting depth, system potential energy, cutting force and work piece temperature will increase correspondingly while the surface quality of machined work piece will decrease.


2014 ◽  
Vol 21 (6) ◽  
pp. 382-386 ◽  
Author(s):  
Ch Jo ◽  
Jh Ahn ◽  
Yd Shon ◽  
Gc Cho

Introduction The aim of this study was to determine the effect of hand positioning on the quality of external chest compression (ECC) by novice rescuers. Methods This observational simulation study was conducted for 117 included participants. After completion of an adult cardiopulmonary resuscitation (CPR) training program for 3-h, the participants selected which of their hands would be in contact with the mannequin during ECC and performed 5 cycles of single rescuer CPR on a recording mannequin. The participants were assigned to 2 groups: the dominant hand group (DH; n=40) and the non-dominant hand group (NH; n=29). The depth and rate of ECC were analysed to compare the effectiveness of ECC between 2 groups. Results The rate of ECC was significantly faster in the DH group (mean, 117.3 ±11.4/min) than in the NH group (mean, 110.9±12.2/min) (p=0.028). However, the depth of ECC in the dominant hand group (mean, 52.4±5.9 mm) was not significantly different from that in the non-dominant hand group (mean, 50.8±6.0 mm) (p=0.287). Similarly, the portion of ECC with inadequate depth in the dominant hand group (mean, 1.8±4.3%) was not significantly different from that in the non-dominant hand group (mean, 5.3±15.6%) (p=0.252). Conclusions ECC can be performed with an acceptably higher rate of compressions when the dominant hand of the novice rescuer is placed in contact with the sternum. However, the position of the dominant hand does not affect the depth of ECC. (Hong Kong j.emerg.med. 2014;21:382-386)


2013 ◽  
Vol 28 (1) ◽  
pp. 23-29 ◽  
Author(s):  
Tatjana Perovic ◽  
Snjezana Hrncic

Olive fruit fly is the most harmful pest of olive fruits and important for oil production. Damage involves yield reduction as a consequence of premature fruit drop, but also a reduced quality of olive oil and olive products. There is little available data regarding the biology of Bactrocera oleae in Montenegro. Knowledge of the pest life cycle and development would improve optimization of insecticide application timing and protection of fruits, and reduce adverse effects on the environment. Investigation was conducted on the Zutica variety in an olive grove located in Bar during a three-year period. Population dynamics of the pre-imaginal stages and level of fruit infestation were monitored from mid-July until the end of October. The results of this three-year investigation showed that the beginning of infestation was always at the end of July. It was also found that, depending on environmental conditions, the level of infestation was low until the end of August. In September and October it multiplied, and reached maximum by the end of October. Regarding infestation structure, eggs and first instar larvae were the dominant developmental stages of the pest until the middle of September. From mid-September until mid-October all developmental stages (eggs, larvae, pupae) were equally present in infested fruits. Pupae, cocoons and abandoned galleries prevailed until the harvest.


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