Nevertheless, its limitations like high rate of false-positive results in bacille Calmette-Guérin (BCG) vaccinated or in atypical environmental mycobacterium infected individuals as well as high rate of false-negative results among immunosuppressed individuals made difficult its utilization for the screening of LTBI, especially in regions where BCG vaccination and HIV/AIDS are common [ 6, 7].
This differentiation is difficult and requires utilization of molecular fingerprinting techniques to confirm that the identified bacteria, before and after therapy, are genetically identical [ 7].
This observation implies that it would be difficult to use unmodified ZnO as a catalyst for a direct utilization and mineralization of chlorophenols.
Diffusion of renewable energy utilization is difficult because of its entrepreneurial nature and related technological, investment, political, and market uncertainties.
As the area covered by C3 and population were difficult to estimate, the utilization index cannot be computed.
South Africa also has many particularly aggressive hybrids that form dense shrub-dominated stands, which makes the utilization approach difficult (Zimmermann et al. 2006).
Since immunization is only reported as a 'planned' expense and not an actual expense, it is very difficult to validate actual utilization by missions who may significantly alter their planned allocation of funds after the reporting process is complete.
For a variety of reasons, some facilities will find it difficult to increase the utilization of services (i.e. long distances/lack of transport, strong preferences for home birth among the local population, etc)., while others may find it easier.
In archaea, insights into dynamics of Ni and Co utilization were difficult because only a small number of archaeal genomes were sequenced and nearly all of these organisms use both metals.
Because individuals with HIV/AIDS often have complex medical and social needs, the impact of housing status on medical service utilization is difficult to isolate from the impact of conditions that may worsen during periods of homelessness such as depression and substance abuse.
