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**21**

**Chapter 2**

World

**Abstract**

organisms.

**1. Introduction**

polymerase to replicate RNA [4].

Origin of DNA Repair in the RNA

The early history of life on Earth likely included a stage in which life existed as self-replicating protocells with single-stranded RNA (ssRNA) genomes. In this RNA world, genome damage from a variety of sources (spontaneous hydrolysis, UV, etc.) would have been a problem for survival. Selection pressure for dealing with genome damage would have led to adaptive strategies for mitigating the damage. In today's world, RNA viruses with ssRNA genomes are common, and these viruses similarly need to cope with genome damage. Thus ssRNA viruses can serve as models for understanding the early evolution of genome repair. As the ssRNA protocells in the early RNA world evolved, the RNA genome likely gave rise, through a series of evolutionary stages, to the double-stranded DNA (dsDNA) genome. In ssRNA to dsDNA evolution, genome repair processes also likely evolved to accommodate this transition. Some of the basic features of ssRNA genome repair appear to have been retained in descendants with dsDNA genomes. In particular, a type of strandswitching recombination occurs when ssRNA replication is blocked by a damage in the template strand. Elements of this process appear to have a central role in recombinational repair processes during meiosis and mitosis of descendant dsDNA

**Keywords:** RNA world, RNA virus, recombination repair, copy-choice, synthesisdependent strand annealing (SDSA), DNA repair, archaea, genome damage,

Protocellular organisms may have come into existence 2.5 to 3.5 billion years ago [1, 2]. Woese [3] proposed that the genomes of the early protocellular forms of life were individual strands of RNA rather than DNA, and that these RNA strands were present as separate genome segments, rather than being linked together end-to-end as is generally the case for genes in DNA. The idea that, during an early period in the evolution of life, genetic information was stored and transmitted solely by RNA molecules has come to be known as the "RNA world hypothesis." This hypothesis is currently being tested by many investigators. Of particular significance, Horning and Joyce [4] have demonstrated that the replication of genetic information and its conversion into functional molecules can be accomplished with RNA in the complete absence of protein. RNA molecules with catalytic activity are called ribozymes. An RNA ribozyme developed by Horning and Joyce can act as an RNA

strand-switching, self-replication, single-stranded RNA

*Harris Bernstein and Carol Bernstein*


**2. Design Phases and Preliminary Evaluation of the Implementation Process of the "Understanding COVID" Strategy**

#### *2.1. Hearing Citizen's Voice*

The first step in designing the strategy was based on analysis through a survey to evaluate weaknesses, perceived strengths, and topics and contents of interest. This was sent by phone using the WhatsApp application, adapting to the technology available at the time of confinement. The survey met the requirements of Organic Law 3/2018 [14] in terms of data analysis and dissemination. Participants were asked to answer six questions on a 6-item Likert scale (0: Strongly disagree; 1: Disagree; 2: Slightly Disagree; 3: Slightly Agree; 4: Agree; 5: Strongly agree) and an additional open-ended question to capture proposals on COVID-19 prevention and control training ("What else would you like us to include in that training? Write down what you deem important in these times of pandemic").

Table 1 shows the responses to this first online survey incorporating the opinion of citizens between 9 March 2020 and 13 March 2020 (106 responses in one week). The questions were not mandatory, so not all of them were answered by all respondents, and the average response rate was 93%. The percentage of agreement was greater than or equal to 80% in the answer "strongly agree" in questions 1, 3, 5, and 6 and greater than or equal to 65% in the same answer in questions 2 and 4.

In the open-ended question, respondents answered that their greatest interest was the formations focused on the use of "personal protective equipment", information on face masks and on dealing with emotions in times of pandemics.

**Table 1.** Initial questionnaire for collecting information from citizens.

\* 0: "Strongly disagree" → 5: "Strongly agree".

The continuous collection of information from participants was considered a priority due to the relevance of incorporating real doubts and needs, as well as adapting the strategy to all target audiences. Thereby, in a later phase, a survey was designed and sent to all participants who took part in the training so that they could anonymously and voluntarily evaluate the usefulness, accessibility, contents, teaching methodology and satisfaction, as shown in Table 2. Along with the previous results, information was also collected from the participants in the training sessions (e.g., opinions or testimonials), thanks to which new content was al-so developed and work was done with groups or sectors that were valued as relevant at different times.

A total of 472 responses were collected from the continuous information and satisfaction survey. Of these, 65 were from participants in the activity aimed at the school families' associations, 111 from those aimed at secondary schools, 256 from the "Drop by Drop" action training designed for individual citizens, and 40 from the "First Quality Air", the specific training offered to the hotel industry.

The percentages of agreement for usefulness, time and accessibility based on the Likert scale are shown in Table 3. In summary, when asked about the usefulness of the training, the activity with the best result was the training for catering "First Quality Air" with 88% "strongly agree" followed by the training of secondary schools with 86%, family associations with 78% and "Gota a Gota" with 77%. In relation to the duration of the training, all four pieces of training have high scores of "yes", with the secondary schools' training reaching 100% agreement, followed by the Family Associations' training with 97% and "Gota a Gota" and "First Quality Air" with 95% each. In the section related to accessibility, the "strongly agree" scores ranged from 86% for training in secondary schools, 83% for Family Associations and "Gota a Gota," and finally, "First Quality Air" with 80%.

**Table 2.** Questionnaire for continuous collection of citizen information.

**Table 3.** Percentage of agreement with usefulness, time and accessibility from the questionnaire for the continuous collection of information for citizens.

The percentages of agreement with the satisfaction-based question on the Likert scale are shown in Table 4. In this table, we can be seen that satisfaction was measured with a broader Likert scale (0–10), with the highest score in all cases being 10, with 49% in families' associations, 85% in "First Quality Air ", 86% in secondary schools and finally 89% in the "Drop by Drop".

**Table 4.** Percentage of agreement with satisfaction from the questionnaire for the continuous collection of information for citizens.

Along with the previous results, information was also collected from the participants in the training sessions (e.g., opinions or testimonials), thanks to which new content was also developed and work was done with groups or sectors that were valued as relevant at different times.