Q: In this task, you are given a paragraph (from a research paper) and your task is to classify each sentence of the paragraph (assume n sentence) into the following categories: Background, Purpose, Method, Finding/Contribution, or Other. Return the output in this format: 1 - category of sentence 1, 2 - category of sentence 2, ..., n - category of sentence n; where each number indicates the order of the sentence. The categories can be identified using the following questions: 
 Background: - Why is this problem important? - What relevant works have been done before? - What did the previous works miss? - What are the high-level research questions? - How might this help other researchers?
 Purpose: - What specific things do the researchers want to do? - What specific knowledge do the researchers want to know? - What specific hypothesis do the researchers want to test?
 Method: - How did the researchers do it or find it out? - What are the procedures and steps of this research?
 Finding/Contribution: - What did the researchers find out? Did the proposed methods work? - Did things behave as the researchers expected?
Other: put every text fragment that does not fit into any of the categories above here. Put a sentence here if its not in English, is not part of the article, contains numbers and dates, is a caption of a figure or a table, is a formatting error, or you are not sure about it.
Quantification of physiologic defensin concentrations in vivo is complex, as defensins are present at high local concentrations within specific cell types or upon release from cells into confined anatomical niches (e.g., crypts of the small intestine) but can become diluted in extracellular fluids. For the myeloid -defensins, Daher et al. estimated ~3 mM (10 mg/ml) HNPs in neutrophils, with even higher local concentrations in the azurophilic granules in which they are stored 1 . For the enteric -defensins, Ayabe et al. estimated concentrations of ≥3.5 mM (15-100 mg/ml) in the crypt lumen, the site of Paneth cell degranulation 31 . These concentrations are likely similar in the human small intestine, where HD5 expression exceeds that of HD6 by 6-fold 32 . In healthy patients, epithelial lining fluid of the lung contains 31-79 nM HNP1-3, nasal fluid contains ~2.7 M HNP1-3, saliva contains 0.3-3 M HNP1-3, and vaginal secretions contain ~1.5 M HNPs and 0.3-14 M HD5 23; 33; 34; 35; 36; 37; 38 . For the -defensins, 5-10 nM HBD2 has been measured in nasal fluid 37; 39 . However, in certain disease states defensin levels can be highly elevated. For example, 57 M to 2.4 mM concentrations of HNP1 have been found in epithelial lining fluid of cystic fibrosis patients 36 . Overall, the concentrations of defensins present in vivo are generally within the range that is needed for direct antiviral activity by -defensins and generally below the concentrations required for direct antiviral activity by -defensins. Wilson et al. 
A:
1 - finding, 2 - finding, 3 - finding, 4 - finding, 5 - finding, 6 - finding, 7 - finding, 8 - finding, 9 - finding, 10 - finding, 11 - finding, 12 - finding, 13 - finding, 14 - finding, 15 - finding, 16 - finding, 17 - finding, 18 - finding, 19 - other