The use of augmented reality for solving arithmetic problems for preschool children

Preschool children are required to acquire problem-solving ability and related time and sequence concepts to solve mathematical story problems. The maturation and pervasion of disruptive technologies, such as augmented reality (AR), may help preschool children to better acquire this knowledge and skills. However, it is still unknown how preschoolers would make use of AR as a learning tool for tackling arithmetic story problems with the involvement of the concepts of time and sequence. Consequently, the present study attempted to employ direct observation and interview methods to compare and gain insights into young children’s learning behaviors under traditional 2D pictorial and AR contexts. In line with the early development trajectories of a normal child aged 4–6 years old, a series of planned arithmetic problems which primarily comprised seriation (e.g. first, second, third) and scheduling (e.g. arriving, leaving) concepts were structured in scenario-based stories and designed specifically for preschool children. The findings of the current study reveal that AR intervention may well develop the problem-solving and independent mathematical thinking ability for preschool children by encouraging them to consider all information involved in the story problems, rather than simply guessing the answer from a 2D pictorial mode. Finally, based on the fact that the majority of preschool children still rely on a concrete counting method, the recommendation is to integrate AR technology into the traditional pictorial scenarios for the purpose of supporting the development of children’s ability to solve arithmetic story problem

Increased Genetic Diversity of HIV-1 Circulating in Hong Kong

HIV-1 group M strains are characterized into 9 pure subtypes and 48 circulating recombinant forms (CRFs). Recent studies have identified the presence of new HIV-1 recombinants in Hong Kong and their complexity continues to increase. This study aims to characterize the HIV-1 genetic diversity in Hong Kong. Phylogenetic analyses were performed by using HIV-1 pol sequences including protease and partial reverse transcriptase isolated from 1045 local patients in Hong Kong from 2003 to 2008. For the pol sequences with unassigned genotype, the evidence of recombination was determined by using sliding-window based bootscan plots and their env C2V3 region were also sequenced. Epidemiological background of these patients was further collected. The pol phylogenetic analyses highlighted the extent of HIV-1 genetic diversity in Hong Kong. Subtype B (450/1045; 43.1%) and CRF01_AE (469/1045; 44.9%) variants were clearly predominant. Other genotypes (126/1045; 12.1%) including 3 defined subtypes, 10 CRFs, 1 unassigned subtype and 33 recombinants with 11 different mosaic patterns were observed. Recombinants of subtype B and CRF01_AE were mainly found among local Chinese MSM throughout 2004 to 2008, while the CRF02_AG and subtype G recombinants were circulating among non-Chinese Asian population in Hong Kong through heterosexual transmission starting from 2008. Our study demonstrated the complex recombination of HIV-1 in Hong Kong and the need in developing surveillance system for tracking the distribution of new HIV-1 genetic variants

Validation of a new three-dimensional imaging system using comparative craniofacial anthropometry

Abstract Background The aim of this study is to validate a new three-dimensional craniofacial stereophotogrammetry imaging system (3dMDface) through comparison with manual facial surface anthropometry. The null hypothesis was that there is no difference between craniofacial measurements using anthropometry vs. the 3dMDface system. Methods Facial images using the new 3dMDface system were taken from six randomly selected subjects, sitting in natural head position, on six separate occasions each 1 week apart, repeated twice at each sitting. Exclusion criteria were excess facial hair, facial piercings and undergoing current dentofacial treatment. 3dMDvultus software allowed facial landmarks to be marked and measurements recorded. The same measurements were taken using manual anthropometry, using soluble eyeliner to pinpoint landmarks, and sliding and spreading callipers and measuring tape to measure distances. The setting for the investigation was a dental teaching hospital and regional (secondary and tertiary care) cleft centre. The main outcome measure was comparison of the craniofacial measurements using the two aforementioned techniques. Results The results showed good agreement between craniofacial measurements using the 3dMDface system compared with manual anthropometry. For all measurements, except chin height and labial fissure width, there was a greater variability with the manual method compared to 3D assessment. Overall, there was a significantly greater variability in manual compared with 3D assessments (p < 0.02). Conclusions The 3dMDface system is validated for craniofacial measurements

Do Bankart lesions heal better in shoulders immobilized in external rotation?: A randomized single-blind study of 55 patients examined with MRI

Background and purpose Immobilization in external rotation (ER) for shoulder dislocation has been reported to improve the coaptation of Bankart lesions to the glenoid. We compared the position of the labrum in patients treated with immobilization in ER or internal rotation (IR). A secondary aim was to evaluate the rate of Bankart lesions

Fluorescent Microangiography Is a Novel and Widely Applicable Technique for Delineating the Renal Microvasculature

Rarefaction of the renal microvasculature correlates with declining kidney function. However, current technologies commonly used for its evaluation are limited by their reliance on endothelial cell antigen expression and assessment in two dimensions. We set out to establish a widely applicable and unbiased optical sectioning method to enable three dimensional imaging and reconstruction of the renal microvessels based on their luminal filling. The kidneys of subtotally nephrectomized (SNx) rats and their sham-operated counterparts were subjected to either routine two-dimensional immunohistochemistry or the novel technique of fluorescent microangiography (FMA). The latter was achieved by perfusion of the kidney with an agarose suspension of fluorescent polystyrene microspheres followed by optical sectioning of 200 µm thick cross-sections using a confocal microscope. The fluorescent microangiography method enabled the three-dimensional reconstruction of virtual microvascular casts and confirmed a reduction in both glomerular and peritubular capillary density in the kidneys of SNx rats, despite an overall increase in glomerular volume. FMA is an uncomplicated technique for evaluating the renal microvasculature that circumvents many of the limitations imposed by conventional analysis of two-dimensional tissue sections

The unmasking of Pneumocystis jiroveci pneumonia during reversal of immunosuppression: Case reports and literature review

Background: Pneumocystis jiroveci pneumonia (PCP) is an important opportunistic infection among immunosuppressed patients, especially in those infected with human immunodeficiency virus (HIV). The clinical presentation of PCP in immunosuppressed patients have been well-reported in the literature. However, the clinical importance of PCP manifesting in the setting of an immunorestitution disease (IRD), defined as an acute symptomatic or paradoxical deterioration of a (presumably) preexisting infection, which is temporally related to the recovery of the immune system and is due to immunopathological damage associated with the reversal of immunosuppressive processes, has received relatively little attention until recently. Case presentation: We aim to better define this unique clinical syndrome by reporting two cases of PCP manifesting acutely with respiratory failure during reversal of immunosuppression in non-HIV infected patients, and reviewed the relevant literature. We searched our databases for PCP cases manifesting in the context of IRD according to our predefined case definition, and reviewed the case notes retrospectively. A comprehensive search was performed using the Medline database of the National Library of Medicine for similar cases reported previously in the English literature in October 2003. A total of 28 non-HIV (excluding our present case) and 13 HIV-positive patients with PCP manifesting as immunorestitution disease (IRD) have been reported previously in the literature. During immunorestitution, a consistent rise in the median CD4 lymphocyte count (28/μL to 125/μL), with a concomitant fall in the median HIV viral load (5.5 log10 copies/ml to 3.1 log10 copies/ml) was observed in HIV-positive patients who developed PCP. A similar upsurge in peripheral lymphocyte count was observed in our patients preceding the development of PCP, as well as in other non-HIV immunosuppressed patients reported in the literature. Conclusions: PCP manifesting as IRD may be more common than is generally appreciated. Serial monitoring of total lymphocyte or CD4 count could serve as a useful adjunct to facilitate the early diagnosis and pre-emptive treatment of this condition in a wide range of immunosuppressed hosts, especially in the presence of new pulmonary symptoms and/or radiographic abnormalities compatible with the diagnosis. © 2004 Wu et al; licensee BioMed Central Ltd.published_or_final_versio