216 research outputs found
Behavior Domains in Theory and in Practice
The concept of a behavior domain is a reasonable and essential foundation for psychometric work based on true score theory, the linear model of common factor analysis, and the nonlinear models of item response theory. Investigators applying these models to test data generally treat the true scores or factors or traits as abstractive psychological attributes: common properties of the items, possibly with some inconsistency between their practice and their theoretical statements. A countably infinite item domain defines an attribute uniquely, and a function of the domain item scores gives an identified measure of it, to be estimated from a finite set of item scores, with a defined error of measurement. In test development the investigator must consider and justify the assumption that an item domain exists for the specific measurement application and is large enough to be treated as infinite for that application
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The development of a curriculum for a college course in fabrication for welders
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Principles and practice in reporting structural equation analyses
Principles for reporting analyses using structural equation modeling are reviewed, with the goal of supplying readers with complete and accurate information. It is recommended that every report give a detailed justification of the model used, along with plausible alternatives and an account of identifiability. Nonnormality and missing data problems should also be addressed. A complete set of parameters and their standard errors is desirable, and it will often be convenient to supply the correlation matrix and discrepancies, as well as goodness-of-fit indices, so that readers can exercise independent critical judgment. A survey of fairly representative studies compares recent practice with the principles of reporting recommended here
LOCAL IgA-MEMORY RESPONSE TO BACTERIAL ANTIGENS *
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72248/1/j.1749-6632.1983.tb26912.x.pd
Annexin A8 identifies a subpopulation of transiently quiescent c-kit positive luminal progenitor cells of the ductal mammary epithelium
We have previously shown that Annexin A8 (ANXA8) is strongly associated with the basal-like subgroup of breast cancers, including BRCA1-associated breast cancers, and poor prognosis; while in the mouse mammary gland AnxA8 mRNA is expressed in low-proliferative isolated pubertal mouse mammary ductal epithelium and after enforced involution, but not in isolated highly proliferative terminal end buds (TEB) or during pregnancy. To better understand ANXA8âs association with this breast cancer subgroup we established ANXA8âs cellular distribution in the mammary gland and ANXA8âs effect on cell proliferation. We show that ANXA8 expression in the mouse mammary gland was strong during pre-puberty before the expansion of the rudimentary ductal network and was limited to a distinct subpopulation of ductal luminal epithelial cells but was not detected in TEB or in alveoli during pregnancy. Similarly, during late involution its expression was found in the surviving ductal epithelium, but not in the apoptotic alveoli. Double-immunofluorescence (IF) showed that ANXA8 positive (+ve) cells were ER-alpha negative (âve) and mostly quiescent, as defined by lack of Ki67 expression during puberty and mid-pregnancy, but not terminally differentiated with ~15% of ANXA8 +ve cells re-entering the cell cycle at the start of pregnancy (day 4.5). RT-PCR on RNA from FACS-sorted cells and double-IF showed that ANXA8+ve cells were a subpopulation of c-kit +ve luminal progenitor cells, which have recently been identified as the cells of origin of basal-like breast cancers. Over expression of ANXA8 in the mammary epithelial cell line Kim-2 led to a G0/G1 arrest and suppressed Ki67 expression, indicating cell cycle exit. Our data therefore identify ANXA8 as a potential mediator of quiescence in the normal mouse mammary ductal epithelium, while its expression in basal-like breast cancers may be linked to ANXA8âs association with their specific cells of origin
Structural Equations Modeling
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/144267/1/jcpy83.pd
Role of interferonâÎł and inflammatory monocytes in driving colonic inflammation during acute Clostridium difficile infection in mice
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136491/1/imm12700.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136491/2/imm12700_am.pd
The role of Grâ1+ cells and tumour necrosis factorâα signalling during Clostridium difficile colitis in mice
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110845/1/imm12425.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/110845/2/imm12425-sup-0001-FigS1-2.pd
Interleukinâ22 and CD160 play additive roles in the host mucosal response to Clostridium difficile infection in mice
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110834/1/imm12414.pd
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