Assume data context is in variable context
from c in context.conferences
join ctry in context.country on c.CountryId equals ctry.CountryId
join s1 in context.State on c.StateId equals s.StateId into s2
from s in s2.DefaultIfEmpty()
where
c.DisplayStartDate <= System.DateTime.Now
&& c.DisplayEndDate >= System.DateTime.Now
&& c.DeletedFlag == 0 // or false if represented as a bool
&& c.Publish == 1 // or true if represented as a bool
&& context.UserContent.Any(
x => x.SpecialityId == c.specialityId
&& x.UserId == currentUserId
&& x.DeletedFlag == 0
// or if represented as a bool "&& !x.DeletedFlag"
)
select new {
c.ConferenceId,
c.SpecialtyId,
c.name,
c.city,
stateabbr = s.abbr,
countryname = ctry.name,
c.startdate,
c.enddate
}