scholarly journals Looking for Peekaboo

2021 ◽  
Vol 40 ◽  
pp. 43-60
Author(s):  
Claiborne Rice

In the context of a preliminary investigation of peekaboo play in a local day care, this essay examines the particulars of one child’s actions as she attempts to engage another child in peekaboo. Four elements of the child’s performance contribute to its evaluation as peekaboo: the stylized motions of looking and eye-covering, the intent to make and keep eye contact with the play partner, the rhythmic timing of covering-uncovering motions, and the opportunistic nature of the attempt to play. Considering peekaboo as a folk illusion puts these kinds of early performances in the context of a developmental trajectory that spans the entire childhood.

Author(s):  
R.P. Apkarian ◽  
J.S. Sanfilippo

The synthetic androgen danazol, is an isoxazol derivative of ethisterone. It is utilized in the treatment of endometriosis, fibrocystic breast disease, and has a potential use as a contraceptive. A study was designed to evaluate the ultrastructural changes associated with danazol therapy in a rat model. The preliminary investigation of the distal segment of the rat uterine horn was undertaken as part of a larger study intended to elucidate the effects of danazol on the female reproductive tract.Cross-sections (2-3 mm in length) of the distal segment of the uterine horn from sixteen Sprague-Dawley rats were prepared for SEM. Ten rats in estrus served as controls and six danazol treated rats were noted to have alterations of the estrus cycle i.e. a lag in cycle phase or noncycling patterns. Specimens were fixed in 3% glutaraldehyde in 0.05M phosphate buffer containing CaCl2 at pH 7.0-7.4 and chilled to 4°C. After a brief wash in distilled water, specimens were passed through a graded series of ethanol, critical point dryed in CO2 from absolute ethanol, and coated with 6nm Au. Observations were made with an IS1-40 SEM operated at 15kV.


Author(s):  
Becky Jackson

Preliminary investigation has indicated similarity in hepatic ultrastructural morphology in nutritional deprivation, and cyanide induced hepatic necrosis. Analysis of hepatic tissue has indicated disruption of intracellular membranes, specifically, reduction in rough endoplasmic reticulum (RER) mitochondrial integrity, and glycogen stores. An increase in smooth endoplasmic reticulum (SER) portion was observed.To further investigate the apparent equivalence of necrotic morphology, ultrastructura1ly, BDF1 mice were subjected to senescence, nutritional deprevation, potassium cyanide (KCN) induced toxemia, and acetaminophen induced toxemia. Controls were utilized to ellucidate non-necrotic hepatocellular normals. U1trastructura1 investigation of controls (Fig. 1) shows densely granular RER, abundant glycogen stores, and morphologically normal mitochondria. Subjects with acetaminophen induced necrosis exhibit reduced normal RER with increased levels of dialated, vesicular RER in apparent conversion to SER (Fig. 2), loss of mitochondrial integrity, and glycogen store reduction. Senescent subjects exhibit a pronounced increase in SER and loss of glycogen store. (Fig. 3). Investigation of the senescent SER at high magnification (Fig. 5) indicates that the SER is arising from degranulating and vesiculating RER.


Author(s):  
Richard L. Klein ◽  
Åsa K. Thureson-Klein ◽  
Harihara M. Mehendale

KeponeR (decachlorooctahydro-1,3,4-metheno-2H-cyclobuta[cd]pentalen-2-one) is an insecticide effective against ants and roaches. It can cause severe toxicity in fishes, birds, rodents and man. Prominent effects include hepatic lipid deposition and hypertrophy, impairment of reproductive capacity and neurological disorders. Mitochondrial oligomycin-sensitive Mg2+-ATPase is also inhibited. The present study is a preliminary investigation of tissue ultrastructural changes accompanying physiological signs of acute toxicity, which after two days treatment include: pronounced hypersensitivity and tremor, various degrees of anorexia and adipsia, and decreased weight gain.Three different series of adult male Sprague-Dawley rats (Charles River or CD-I) were treated by intubation with Kepone in corn oil at a dose of 50 mg per kg for 3 successive days or at 200 ppm in food for 8 days. After ether anesthesia, rats were immediately perfused via a cannula in the left ventricle with 4% p-formaldehyde and 0.5% glutaraldehyde in Millonig's phosphate buffer at pH 7.2 for 20-30 min at 22°C.


2019 ◽  
Vol 62 (9) ◽  
pp. 3397-3412
Author(s):  
Michelle I. Brown ◽  
David Trembath ◽  
Marleen F. Westerveld ◽  
Gail T. Gillon

Purpose This pilot study explored the effectiveness of an early storybook reading (ESR) intervention for parents with babies with hearing loss (HL) for improving (a) parents' book selection skills, (b) parent–child eye contact, and (c) parent–child turn-taking. Advancing research into ESR, this study examined whether the benefits from an ESR intervention reported for babies without HL were also observed in babies with HL. Method Four mother–baby dyads participated in a multiple baseline single-case experimental design across behaviors. Treatment effects for parents' book selection skills, parent–child eye contact, and parent–child turn-taking were examined using visual analysis and Tau-U analysis. Results Statistically significant increases, with large to very large effect sizes, were observed for all 4 participants for parent–child eye contact and parent–child turn-taking. Limited improvements with ceiling effects were observed for parents' book selection skills. Conclusion The findings provide preliminary evidence for the effectiveness of an ESR intervention for babies with HL for promoting parent–child interactions through eye contact and turn-taking.


2020 ◽  
Vol 63 (2) ◽  
pp. 487-498
Author(s):  
Puisan Wong ◽  
Man Wai Cheng

Purpose Theoretical models and substantial research have proposed that general auditory sensitivity is a developmental foundation for speech perception and language acquisition. Nonetheless, controversies exist about the effectiveness of general auditory training in improving speech and language skills. This research investigated the relationships among general auditory sensitivity, phonemic speech perception, and word-level speech perception via the examination of pitch and lexical tone perception in children. Method Forty-eight typically developing 4- to 6-year-old Cantonese-speaking children were tested on the discrimination of the pitch patterns of lexical tones in synthetic stimuli, discrimination of naturally produced lexical tones, and identification of lexical tone in familiar words. Results The findings revealed that accurate lexical tone discrimination and identification did not necessarily entail the accurate discrimination of nonlinguistic stimuli that followed the pitch levels and pitch shapes of lexical tones. Although pitch discrimination and tone discrimination abilities were strongly correlated, accuracy in pitch discrimination was lower than that in tone discrimination, and nonspeech pitch discrimination ability did not precede linguistic tone discrimination in the developmental trajectory. Conclusions Contradicting the theoretical models, the findings of this study suggest that general auditory sensitivity and speech perception may not be causally or hierarchically related. The finding that accuracy in pitch discrimination is lower than that in tone discrimination suggests that comparable nonlinguistic auditory perceptual ability may not be necessary for accurate speech perception and language learning. The results cast doubt on the use of nonlinguistic auditory perceptual training to improve children's speech, language, and literacy abilities.


2006 ◽  
Vol 40 (11) ◽  
pp. 22
Author(s):  
MELINDA TANZOLA
Keyword(s):  
Day Care ◽  

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