It sounds like you are staying active and conducting research so that is good! I would say as far as safety schools it is kind of a crap shoot (in my experience) just apply to a lot to be safe; Miami U could potentially be a safety school. I would maybe start drafting a resume, personal statement, and other required writing samples before your senior year fall semester starts because the deadlines tend to sneak up on ya. I used USNews as a loose guide, I personally feel you can not get caught up in rankings, but to start with you can look there. Additionally, you need to consider the specialty you want to go into. For example, a school may be conducting great research with great professors in one or two areas but have an overall lower ranking. For instance, UNC and analytical chemistry, while they are considered 15th overall they have what I consider a top analytical program. If spectroscopy is what you are interested in maybe find a school that has many professors doing that sort of research, because generally you should find a school that has multiple professors you would want to work for. Lastly, You should probably like the location as you will be there at least 5 years. To sum, I think you need to take many things into consideration when looking at schools. Good luck! Sounds like you are on the right track
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