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Infants' oculomotor tracking develops rapidly but is poorer when there are horizontal and vertical movement components. Additionally, persistence of objects moving through occlusion emerges at 4 months but initially is absent for objects moving obliquely. In two experiments we recorded eye movements of 32 4-month-old and 32 6-month-old infants (mainly Caucasian-White) tracking horizontal, vertical, and oblique trajectories. Infants tracked oblique trajectories less accurately, but six-month-olds tracked more accurately, such that they tracked oblique trajectories as accurately as 4-month-olds tracked horizontal and vertical trajectories. Similar results emerged when the object was temporarily occluded. Thus, 4-month-olds’ tracking of oblique trajectories may be insufficient to support object persistence, whereas 6-month-olds may track sufficiently accurately to perceive object persistence for all trajectory orientations.

Infants’ oculomotor tracking develops rapidly but is poorer when there are horizontal and vertical movement components. Additionally, persistence of objects moving through occlusion emerges at 4 months but initially is absent for objects moving obliquely. In two experiments, we recorded eye movements of thirty-two 4- month-old and thirty-two 6-month-old infants (mainly Caucasian-White) tracking horizontal, vertical, and oblique trajectories. Infants tracked oblique trajectories less accurately, but 6-month olds tracked more accurately such that they tracked oblique trajectories as accurately as 4-month olds tracked horizontal and vertical trajectories. Similar results emerged when the object was temporarily occluded. Thus, 4-month olds’ tracking of oblique trajectories may be insufficient to support object persistence, whereas 6-month olds may track sufficiently accurately to perceive object persistence for all trajectory orientations.

Attention-Deficit Hyperactivity Disorder (ADHD) rates in classrooms have increased considerably in recent years. Previous literature has acknowledged the significance of teachers’ knowledge and attitudes towards ADHD when making referral and intervention decisions. Using Mulholland, Cumming and Jung’s (2015) knowledge (SASK) and attitude (SASA) scales, ADHD training and perceived support were compared across public school teachers (n=165) and teaching assistants (TAs) (n=157) in the UK. Results indicated that teachers and TAs displayed adequate levels of knowledge, and TAs held better knowledge and more positive feelings towards ADHD than teachers. Training increased knowledge for TAs, but not for teachers, and training and support appeared important for both the teachers and TAs’ attitudes. Both teachers and TAs reported inadequate training and expressed a desire for further ADHD training, and a significant association was found between knowledge and attitudes for teachers only. The implications for these findings are discussed.

Perception of object persistence across occlusion emerges at around 4 months of age for objects moving horizontally or vertically. In addition, congruent auditory information for movement enhances perception of persistence of an object moving horizontally. In two experiments, we examined the effect of presenting bimodal (visual and auditory) sensory information, both congruently and incongruently, for a vertical moving object occlusion event. A total of 68 4-month-old infants (34 girls) were tested for perception of persistence of an object moving up and down, passing at each translation behind a centrally placed occluder. Infants were exposed to these visual events accompanied by no sound, spatially colocated sound, or congruent or incongruent pitch–height correspondence sounds. Both spatially colocated and congruent pitch–height auditory information enhanced perception of trajectory continuity. However, no impairment occurred when pitch–height sound information was presented incongruently. These results highlight the importance of taking a multisensory approach to infant perceptual development.

This study investigated maternal prenatal docosahexaenoic acid (DHA) intake and infant cognitive development at 22 months. Estimates for second- and third-trimester maternal DHA intake levels were obtained using a comprehensive Food Frequency Questionnaire. Infants (n = 67) were assessed at 22 months on a novel object search task. Mothers' DHA intake levels were divided into high or low groups, with analyses revealing a significant positive effect of third-trimester DHA on object search task performance. The third trimester appears to be a critical time for ensuring adequate maternal DHA levels to facilitate optimum cognitive development in late infancy.

The main aggrecan catabolite, found in samples of synovial fluid from patients with arthritis, and released from cartilage explant cultures exposed to IL-1, both have the amino-terminal amino acid sequence 374ARGSV... (human sequence enumeration) corresponding to cleavage at the 'aggrecanase site' within the IGD of aggrecan (Sandy et al., 1992, and Lohmander et al., 1993). Loss of aggrecan is a primary event in the destruction of cartilage in arthritic disease. The Glu373- Ala374 bond ('aggrecanase site') within the IGD of the aggrecan core protein is cleaved by members of the ADAMTS family, including ADAMTS-4 and -5 (Tortorella et al., 1999, Abbaszade et al., 1999, and Sandy et al., 2000). In this investigation the model system of chondrocyte-agarose cultures, pioneered by Aydelotte and Kuettner 1988, was used to study the degradation of aggrecan by ADAMTS-4 and -5 in cartilaginous extracellular matrices. Low molecular weight co-migrating 37kD ADAMTS-4 and -5 isoforms were detected in apparently increased amounts in IL-1 a treated cultures compared to controls. These isoforms were bound by heparin and required de novo protein synthesis in the presence of IL-1 a for their generation. As previously reported, de novo protein synthesis in the presence of IL-1 a was also required for 'IGD aggrecanase activity' (Arner et al., 1998). Heparin bound media fractions from IL- 1a treated cultures possessed 'IGD aggrecanase activity' against exogenous aggrecan, which was inhibited by the amino-terminal region of TIMP-3 and was shown to be due to a 37kD isoform of ADAMTS-4. This implicated low molecular weight isoforms of ADAMTS-4 in the aggrecanolysis detected in the presence of IL-1 a. Carboxy-terminal truncation of furin cleaved ADAMTS-4 has previously been proposed as both an activation mechanism for the enzyme (Pratta et al., 2003, Kashiwagi et al., 2004, Gao et al., 2002, Gao et al., 2004 and Flannery et al., 2002) and a means of deregulation of the enzyme's catalytic acti

The main aggrecan catabolite, found in samples of synovial fluid from patients with arthritis, and released from cartilage explant cultures exposed to IL-1, both have the amino-terminal amino acid sequence 374ARGSV... (human sequence enumeration) corresponding to cleavage at the 'aggrecanase site' within the IGD of aggrecan (Sandy et al., 1992, and Lohmander et al., 1993). Loss of aggrecan is a primary event in the destruction of cartilage in arthritic disease. The Glu373- Ala374 bond ('aggrecanase site') within the IGD of the aggrecan core protein is cleaved by members of the ADAMTS family, including ADAMTS-4 and -5 (Tortorella et al., 1999, Abbaszade et al., 1999, and Sandy et al., 2000). In this investigation the model system of chondrocyte-agarose cultures, pioneered by Aydelotte and Kuettner 1988, was used to study the degradation of aggrecan by ADAMTS-4 and -5 in cartilaginous extracellular matrices. Low molecular weight co-migrating 37kD ADAMTS-4 and -5 isoforms were detected in apparently increased amounts in IL-1 a treated cultures compared to controls. These isoforms were bound by heparin and required de novo protein synthesis in the presence of IL-1 a for their generation. As previously reported, de novo protein synthesis in the presence of IL-1 a was also required for 'IGD aggrecanase activity' (Arner et al., 1998). Heparin bound media fractions from IL- 1a treated cultures possessed 'IGD aggrecanase activity' against exogenous aggrecan, which was inhibited by the amino-terminal region of TIMP-3 and was shown to be due to a 37kD isoform of ADAMTS-4. This implicated low molecular weight isoforms of ADAMTS-4 in the aggrecanolysis detected in the presence of IL-1 a. Carboxy-terminal truncation of furin cleaved ADAMTS-4 has previously been proposed as both an activation mechanism for the enzyme (Pratta et al., 2003, Kashiwagi et al., 2004, Gao et al., 2002, Gao et al., 2004 and Flannery et al., 2002) and a means of deregulation of the enzyme's catalytic acti