```xml
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ns4:query_definition xmlns:ns2="http://www.i2b2.org/xsd/cell/crc/psm/1.1/" xmlns:ns4="http://www.i2b2.org/xsd/cell/crc/psm/querydefinition/1.1/" xmlns:ns3="http://www.i2b2.org/xsd/cell/crc/psm/analysisdefinition/1.1/">
    <query_name>Asthma@01:38:12</query_name>
    <query_timing>ANY</query_timing>
    <specificity_scale>0</specificity_scale>
    <panel>
        <panel_number>1</panel_number>
        <panel_timing>ANY</panel_timing>
        <panel_accuracy_scale>100</panel_accuracy_scale>
        <invert>0</invert>
        <total_item_occurrences>1</total_item_occurrences>
        <item>
            <hlevel>4</hlevel>
            <item_name>Asthma</item_name>
            <item_key>\\i2b2_DIAG\i2b2\Diagnoses\Respiratory system (460-519)\Chronic obstructive diseases (490-496)\(493) Asthma\</item_key>
            <item_icon>FA</item_icon>
            <tooltip>Diagnoses \ Respiratory system \ Chronic obstructive diseases \ Asthma</tooltip>
            <class>ENC</class>
            <item_is_synonym>false</item_is_synonym>
        </item>
    </panel>
</ns4:query_definition>

```

I want to find all instances of patients with a diagnosis of asthma in the respiratory system, specifically chronic obstructive diseases, within the timeframe of any date. The specificity scale is set to 0, meaning that all instances will be included, and the accuracy scale is set to 100, indicating high confidence in the results. The panel is set to display only one item, and the class is set to ENC, which stands for Encounter. This query is created using the i2b2 query builder and follows the specified XML structure.