Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Input: Consider Input: Context: Survivors of acute respiratory failure commonly experience long-term psychological sequelae and impaired quality of life. For researchers interested in general mental health, using multiple condition-specific instruments may be unnecessary and inefficient when using the Medical Outcomes Study Short Form (SF)-36, a recommended outcome measure, may suffice. However, relationships between the SF-36 scores and commonly used measures of psychological symptoms in acute survivors of respiratory failure are unknown. Our objective is to examine the relationship of the SF-36 mental health domain (MH) and mental health component summary (MCS) scores with symptoms of depression, anxiety, and post-traumatic stress disorder (PTSD) evaluated using validated psychological instruments. We conducted a cross-sectional analysis of 1,229 participants at 6- and 12-month follow-up assessment using data from five studies from the United States, the United Kingdom, and Australia. Symptoms were assessed using the Hospital Anxiety and Depression Scale (HADS), Depression Anxiety Stress Scales, the Davidson Trauma Scale, Impact of Event Scale (IES), and IES-Revised (IES-R). At 6-month assessment there were moderate to strong correlations of the SF-36 MH scores with HADS depression and anxiety symptoms (r=-0.74 and -0.79) and with IES-R PTSD symptoms (r=-0.60) in the pooled analyses. Using the normalized population mean of 50 on the SF-36 MH domain score as a cut-off, positive predictive values were 16 and 55% for substantial depression; 20 and 68% for substantial anxiety (Depression Anxiety Stress Scales and HADS, respectively); and 40, 44, and 67% for substantial PTSD symptoms (IES-R, IES, and Davidson Trauma Scale, respectively). Negative predictive values were high. The area under the receiver operating characteristics curve of the SF-36 MH score was high for depression, anxiety, and PTSD symptoms (0.88, 0.91, and 0.84, respectively). All results were consistent for the MCS, across the individual studies, and for the 12-month assessment. For researchers interested in general mental health status, the SF-36 MH or MCS offers a strong measure of psychological symptoms prevalent among survivors of acute respiratory failure. For researchers interested in specific conditions, validated psychological instruments should be considered. 
 Question: Symptoms of which disorder are evaluated with the Davidson Trauma Scale?

Output: ptsd


Input: Consider Input: Context: My first visit to Angkor Wat was in 1980. The country had been at war for many years and _ and falling to pieces. Plants were growing out of the roofs, and trees were growing in the courtyards. Today, the temple is the scene of a busy repair program. A team of 15 Indian experts are organizing a workforce of 400 Cambodians, most of them women, who are cleaning, repairing and rebuilding parts of this temple. As I walked through the courtyards, I noticed the Cambodian women devote hours to cleaning carefully a tiny area of stone. Boards are laid down to protect the precious painted stones while the repair work is going on. There are very few machines and little heavy equipment. Workers carry building materials in buckets at the end of long poles. Piles of stones lie in a corner of the courtyard, waiting to be replaced. The work of cleaning the stones is watched over by three Indian chemists. It is a very slow task. First they clean the stones with brushes using buckets of a weak chemical. Then gaps between the stones are filled in. Finally another material is painted onto the stones which will protect them from water forever. Work starts every day at 7 a. m. and goes on until late afternoon six days a week, with a break at midday. Evening is the best time to visit the temple, after the tour groups have left. As the sun sinks lower, shadows spread across the courtyard. After sunset, the sky turns pink. The grey stone towers take on a golden color before turning pink. Nowhere else in the world can there be such a quiet, beautiful place. 
 Question: To clean the stone, how many steps should be followed?

Output: three


Input: Consider Input: Context: If pathogens get through the bodys first two lines of defense, a third line of defense takes over. This third line of defense involves the immune system. It is called an immune response, and is a specific type of response. The immune system has a special response for each type of pathogen. The immune system ( Figure 1.1) is also part of the lymphatic systemnamed for lymphocytes, which are the type of white blood cells involved in an immune response. They include several lymph organs, lymph vessels, lymph, and lymph nodes. This diagram shows the parts of the im- mune system. The immune system in- cludes several organs and a system of vessels that carry lymph. Lymph nodes are located along the lymph vessels. The lymph organs are the red bone marrow, tonsils, spleen, and thymus gland. They are described below ( Figure Each lymph organ has a different job in the immune system. Lymph vessels make up a circulatory system that is similar to the cardiovascular system, which you can read about in a previous concept. Lymph vessels are like blood vessels, except they move lymph instead of blood. Lymph is a yellowish liquid that leaks out of tiny blood vessels into spaces between cells in tissues. Where there is more inflammation, there is usually more lymph in tissues. This lymph may contain many pathogens. The lymph that collects in tissues slowly passes into tiny lymph vessels. It then travels from smaller to larger lymph vessels. Lymph is not pumped through lymph vessels like blood is pumped through blood vessels by the heart. Instead, muscles around the lymph vessels contract and squeeze the lymph through the vessels. The lymph vessels also contract to help move the lymph along. The lymph finally reaches the main lymph vessels in the chest. Here, the lymph drains into two large veins. This is how the lymph returns to the bloodstream. Before lymph reaches the bloodstream, pathogens are removed from it at lymph nodes. Lymph nodes are small, oval structures located along the lymph vessels. They act like filters. Any pathogens filtered out of the lymph at lymph nodes are destroyed by lymphocytes in the nodes. Lymphocytes ( Figure 1.3), a type of white blood cell, are the key cells of an immune response. There are trillions of lymphocytes in the human body. They make up about one quarter of all white blood cells. Usually, fewer than half of the bodys lymphocytes are in the blood. The rest are in the lymph, lymph nodes, and lymph organs. There are two main types of lymphocytes: 1. B cells. This image of a lymphocyte was made with an electron microscope. The lym- phocyte is shown 10,000 times its actual size. 2. T cells. Both types of lymphocytes are produced in the red bone marrow. They are named for the sites where they grow larger. The "B" in B cells stands for bone. B cells grow larger in red bone marrow. The "T" in T cells stands for thymus. T cells mature in the thymus gland. B and T cells must be switched on in order to fight a specific pathogen. Once this happens, they produce an army of cells ready to fight that particular pathogen. How can B and T cells recognize specific pathogens? Pathogens have proteins, often located on their cell surface. These proteins are called antigens. An antigen is any protein that causes an immune response, because it is unlike any protein that the body makes. Antigens are found on bacteria, viruses, and other pathogens. Your body sees these as foreign, meaning they do not belong in your body. 
 Question: t cells mature in the


Output: thymus gland.