In the model outputs presented in this paper we have not placed any restrictions on disposal sites as it is challenging to ascertain an appropriate restriction without site specific assessment of each disposal site.
However, the representativeness of a plot network for an entire landscape remains challenging to ascertain [1], but recommendations on the shape, size or number of sample plots have recently been proposed (e.g. [2 4]).
However, due to the difficulty in strictly controlling the participating subject's mental status and their cognitive behaviors during R-fMRI/T-fMRI scans, it has been challenging to ascertain whether or not an R-fMRI/T-fMRI scan truly reflects the participant's functional brain states during task-free/task-performance periods.
However, it has been challenging to ascertain whether unliganded TRs have transcriptional or physiological functions in a convincing manner since the transplacental supply of maternal T3 to the fetus complicates any analysis in mammalian systems.
Pool sequencing is a relatively young variant of whole genome sequencing, and it is a challenge to ascertain candidate SNP assays for individual genotyping, which may limit the efficiency of replicating pooled sequence loci using individual genotyping [ 42].
Second, exome sequencing of a small number of isolated probands can reveal strong candidate hearing loss mutations, although in some cases it remains challenging to ascertain disease-causing mutations.
However, the representativeness of a plot network for an entire landscape remains challenging to ascertain [ 1], but recommendations on the shape, size or number of sample plots have recently been proposed (e.g. [ 2– 4]).
However, the validity of the self-administered version of the IBHQ may be challenging to ascertain in this population, which might benefit from having the questionnaire administered by an interviewer.
Although it is well established that HIV-positive women are less likely to become pregnant, and that they are substantially more likely to die from numerous causes irrespective of pregnancy (30), it has been a challenge to ascertain the mortality risks to HIV-positive women who do become pregnant, in terms of possible interactions between HIV positivity and pregnancy (31).
Because the identification of emotion centers has been rooted in their ability to mediate emotional learning (LeDoux, 1996; Panksepp, 1998, 2011b), it has been challenging to ascertain whether innate defensive behaviors also reflect underlying emotion states, and therefore to investigate whether structures that mediate these behaviors, such as the medial hypothalamus serve as emotion centers.
