Disentangling the common variance of perfectionistic strivings and perfectionistic concerns : a bifactor model of perfectionism

Perfectionism nowadays is frequently understood as a multidimensional personality trait with two higher-order dimensions of perfectionistic strivings and perfectionistic concerns. While perfectionistic concerns are robustly found to correlate with negative outcomes and psychological malfunctioning, findings concerning the outcomes of perfectionistic strivings are inconsistent. There is evidence that perfectionistic strivings relate to psychological maladjustment on the one hand but to positive outcomes on the other hand as well. Moreover, perfectionistic strivings and perfectionistic concerns frequently showed substantial overlap. These inconsistencies of differential relations and the substantial overlap of perfectionistic strivings and perfectionistic concerns raise questions concerning the factorial structure of perfectionism and the meaning of its dimensions. In this study, several bifactor models were applied to disentangle the common variance of perfectionistic strivings and perfectionistic concerns at the item level using Hill et al.’s (2004) Perfectionism Inventory (PI). The PI measures a broad range of perfectionism dimensions by four perfectionistic strivings and four perfectionistic concerns subscales. The bifactor-(S – 1) model with one general factor defined by concern over mistakes as the reference facet, four specific perfectionistic strivings factors, and three specific perfectionistic concerns factors showed acceptable fit. The results revealed a clear separation between perfectionistic strivings and perfectionistic concerns, as the general factor represented concern over mistakes, while the perfectionistic strivings factors each explained a substantial amount of reliable variance independent of the general factor. As a result, factor scores of the specific perfectionistic strivings factors and the general factor had differential relationships with achievement motivation, neuroticism, conscientiousness, and self-efficacy that met with theoretical expectations, while results for manifest subscale scores were ambiguous. Our results question the existence of reliable sub-constructs of perfectionistic concerns independent of the general factor when defined by concern over mistakes

Primary structures of neuropeptides isolated from the corpora cardiaca of various cetonid beetle species determined by pulsed-liquid phase sequencing and tandem fast atom bombardment mass spectrometry

A peptide with the same retention time on gradient reversed-phase high-performance liquid chromatography was present in the corpora cardiaca of 5 scarabaeid beetles, subfamily Cetoniinae: the three fruit beetle species Pachnoda marginata, P. sinuata and P. aemulae and the two protea beetle species Trichostetha fascularis and T. albopicta. Crude corpora cardiaca material from P. sinuata had a small hypertrehalosaemic effect in American cockroaches and a very weak hyperlipaemic activity in migratory locusts. Injections into P. sinuata caused hypertrehalosaemia when a dose of 1.0 corpora cardiaca equivalents was injected. An identical neuropeptide was isolated, by RP-HPLC, and sequenced by pulsed-liquid phase sequencing employing Edman chemistry after enzymically deblocking the N-terminal 5-oxopyrrolidine-2-carboxylic acid residue, as well as by collision-induced decomposition tandem fast atom bombardment mass spectrometry. The peptide is a blocked octapeptide: Glu-Leu-Asn-Tyr-Ser-Pro-Asp-TrpNH2, previously designated Mem-CC. The synthetic peptide is able to elicit haemolymph carbohydrates in P. sinuata upon injection of low doses. Activity studies using synthetic analogues of this peptide revealed that Tyr4 may be important for receptor recognition/binding. The peptide is synthesized in intrinsic cells of the corpus cardiacum as shown by in vitro incorporation of [3H]Trp and [14C]Tyr in Mem-CC