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Chinese children routinely outperform American peers in standardized tests of mathematics knowledge. To examine mediators of this effect, 95 Chinese and US 5-year-olds completed a test of overall symbolic arithmetic, an IQ subtest, and three tests each of symbolic and non-symbolic numerical magnitude knowledge (magnitude comparison, approximate addition, and number-line estimation). Overall Chinese children performed better in symbolic arithmetic than US children, and all measures of IQ and number knowledge predicted overall symbolic arithmetic. Chinese children were more accurate than US peers in symbolic numerical magnitude comparison, symbolic approximate addition, and both symbolic and non-symbolic number-line estimation; Chinese and U.S. children did not differ in IQ and non-symbolic magnitude comparison and approximate addition. A substantial amount of the nationality difference in overall symbolic arithmetic was mediated by performance on the symbolic and number-line tests.

Children display an early sensitivity to implicit proportions (e.g., 1 of 5 apples vs. 3 of 4 apples), but have considerable difficulty in learning the explicit, symbolic proportions denoted by fractions (e.g., "1/5" vs. "3/4"). Theoretically, reducing the gap between representations of implicit versus explicit proportions would improve understanding of fractions, but little is known about how the representations develop and interact with one another. To address this, we asked 177 third, fourth, and fifth graders (M = 9.85 years, 87 girls, 69% White, 19% low income) to estimate the position of proportionally equivalent integers and fractions on number lines (e.g., 3 on a 0-8 number line vs. 3/8 on a 0-1 number line, Study 1). With increasing age, children's estimates of implicit and explicit proportions became more coherent, such that a child's estimates of fractions on a 0-1 number-line was a linear function of the same child's estimates of equivalent integers. To further investigate whether preexisting integer knowledge can facilitate fraction learning through analogy, we assigned 100 third to fifth graders (M = 10.04 years, 55 girls, 76% White) to an Alignment condition, where children estimated fractions and integers on aligned number lines, or to a No Alignment condition (Study 2). Results showed that aligning integers and fractions on number lines facilitated a better understanding of fractional magnitudes, and increased children's fraction estimation accuracy to the level of college students'. Together, findings suggest that analogies can play an important role in building a coherent understanding of proportions.

Memory for numbers improves with age. One source of this improvement may be learning linear spatial-numeric associations, but previous evidence for this hypothesis likely confounded memory span with quality of numerical magnitude representations and failed to distinguish spatial-numeric mappings from other numeric abilities, such as counting or number word-cardinality mapping. To obviate the influence of memory span on numerical memory, we examined 39 3- to 5-year-olds' ability to recall one spontaneously produced number (1-20) after a delay, and the relation between numeric recall (controlling for non-numeric recall) and quality of mapping between symbolic and non-symbolic quantities using number-line estimation, give-a-number estimation, and counting tasks. Consistent with previous reports, mapping of numerals to space, to discrete quantities, and to numbers in memory displayed a logarithmic-to-linear shift. Also, linearity of spatial-numeric mapping correlated strongly with multiple measures of numeric recall (percent correct and percent absolute error), even when controlling for age and non-numeric memory. Results suggest that linear spatial-numeric mappings may aid memory for number over and above children's other numeric skills.

Impairment in the psychological balance between autonomy and connectedness--referred to as dysfunctional individuation--can interfere with wellbeing and contribute to mental health difficulties. Dysfunctional individuation may reflect problems in earlier parent-child relations, and may account for the relationship between such experiences and psychological distress. However, the prominence of dysfunctional individuation emergent from parental responsiveness, and its link with distress symptoms, may differ according to age and gender. The present study examined associations between perceived parental support, psychological distress, and dysfunctional individuation--including the mediating effect of the latter--among outpatients seeking mental health care. Moderation by age and gender was also examined. A sample of 219 patients completed study assessments. Correlations and conditional process modelling examined associations, including indirect effects of parental responsiveness, with moderation by age and gender, on psychological distress through dysfunctional individuation as a mediator. A significant three-way interaction was observed between perceived parental responsiveness, age, and gender in relation to dysfunctional individuation. Examination of mediation revealed significant moderated moderated mediation, in that the indirect effects of parental responsiveness--through dysfunctional individuation--were significant for younger women and older men. These findings indicated conditional age and gender effects on the role of dysfunctional individuation in mediating perceived early parental responsiveness and psychological distress. Thus, dysfunctional individuation may be a salient clinical concern among patients--particularly younger women and older men--with histories of diminished parental responsiveness. Further research is needed to clarify individuation-related difficulties with respect to age, gender, and other social and contextual factors., Author(s): Alicia Spidel [sup.1] [sup.2] , David Kealy [sup.3] , Dan Kim [sup.2] , Sharan Sandhu [sup.2] , Andrew Izbicki [sup.2] Author Affiliations: (1) grid.258778.7, 0000 0000 9606 4172, Criminology [...]

As a cheaper alternative to the industrial Pt electrode used in quantum-sensitized solar cells, the electrophoresis process is employed to create the low-cost FTO/PbS cathode. For structural cubic and sizes ranging from 40 nm to 200 nm, structure and morphology were investigated using high-resolution scanning electron microscopy and X-ray diffraction. The conversion efficiency of solar cells is significantly impacted by the calcination temperatures of cathodes at 100 ℃, 150 ℃, 200 ℃, and 300 ℃ under vacuum. The FTO/PbS cathode electrode was therefore calcined at 150 ℃ with a maximum efficiency of 3.938%. This happens as a result of the complete fusion of PbS nanoparticles with crystal at 150 ℃, which reduces resistance and increases electron lifetime compared to other temperature combinations.

We present trace gas vertical profiles observed by instruments on the NASA DC-8 and at a ground site during the Korea-US air quality study (KORUS) field campaign in May to June 2016. We focus on the region near the Seoul metropolitan area and its surroundings where both anthropogenic and natural emission sources play an important role in local photochemistry. Integrating ground and airborne observations is the major research goal of many atmospheric chemistry field campaigns. Although airborne platforms typically aim to sample from near surface to the free troposphere, it is difficult to fly very close to the surface especially in environments with complex terrain or a populated area. A detailed analysis integrating ground and airborne observations associated with specific concentration footprints indicates that reactive trace gases are quickly oxidized below an altitude of 700 m. The total OH reactivity profile has a rapid decay in the lower part of troposphere from surface to the lowest altitude (700 m) sampled by the NASA DC-8. The decay rate is close to that of very reactive biogenic volatile organic compounds such as monoterpenes. Therefore, we argue that photochemical processes in the bottom of the boundary layer, below the typical altitude of aircraft sampling, should be thoroughly investigated to properly assess ozone and secondary aerosol formation.

Young children's estimates of numerical magnitude increase approximately logarithmically with actual magnitude. The conventional interpretation of this finding is that children's estimates reflect an innate logarithmic encoding of number. A recent set of findings, however, suggests that logarithmic number-line estimates emerge via a dynamic encoding mechanism that is sensitive to previously encountered stimuli. Here we examine trial-to-trial changes in logarithmicity of numerosity estimates to test an alternative dynamic model (D-MLLM) with both a strong logarithmic component and a weak response to previous stimuli. In support of D-MLLM, first-trial numerosity estimates in both adults (Study 1, 2, 3, and 4) and children (Study 4) were strongly logarithmic, despite zero previous stimuli. Additionally, although numerosity of a previous trial affected adults' estimates, the influence of previous numbers always accompanied the logarithmic-to-linear shift predicted by D-MLLM. We conclude that a dynamic encoding mechanism is not necessary for compressive mapping, but sequential effects on response scaling are a possible source of linearity in adults' numerosity estimation.

Background/objectivesTo evaluate retinal lymphoma treatment at the University of California San Francisco.Subjects/methodsProspective observational audit. Patients were treated systemically, usually with: methotrexate, temozolomide, and rituximab induction; etoposide consolidation; and maintenance with lenalidomide or another immunomodulatory agent. Persistent disease was treated initially by ocular radiotherapy or intravitreal melphalan and latterly by vitrectomy.ResultsThe cohort comprised eight females and two males. The median age was 58 years (range, 38-73). Ocular manifestations were initially unilateral in four patients. Vitreous and subretinal infiltrates were initially present in 16 and 12 eyes, respectively, with three eyes having vision of 20/200 or worse. Four patients had a history of central nervous system (CNS) lymphoma. The median ophthalmic follow-up was 37 months (range, 8-56). Diagnostic and therapeutic vitrectomy were performed in 10 and 2 eyes, respectively. All patients had systemic chemotherapy and eight received maintenance immunotherapy. Four patients underwent ocular radiotherapy, bilaterally in two. One patient received bilateral intravitreal melphalan injections. Two eyes of four patients developed lymphoma during the study and two patients developed CNS disease. At study close, subretinal deposits were subtle in nine eyes and more prominent in two, whereas vitreous infiltrates were minimal in nine eyes, mild in one and moderate in one. The latest visual acuity was significantly worse than at presentation in two eyes and better in two. All patients were alive with no active CNS disease.ConclusionsSubretinal lymphomatous infiltrates respond to systemic chemotherapy with immunomodulatory maintenance, but dense vitreous infiltrates require therapeutic vitrectomy.

Perceptual judgments result from a dynamic process, but little is known about the dynamics of numerosity estimation. Arecent study proposed a computational model (D-MLLM) that combined a model of trial-to-trial changes with a modelfor the internal scaling of discrete number. Here, we tested a surprising prediction of the model – a situation in whichchildren’s estimates of numerosity would be better than those of adults. Consistent with the model simulations, taskcontexts led to a clear developmental reversal: children made more adult-like, linear estimates when to-be-estimatednumbers were descending over trials (backward), whereas adults became more like children with log estimates whennumbers were ascending (forward). In addition, adults’ estimates were subject to inter-trial differences regardless ofstimulus order. In contrast, children were not able to use the trial-to-trial dynamics unless task contexts were salient(forward or backward order), indicating the limited memory capacity for dynamic updates. Together, the model adequatelypredicts both developmental and trial-to-trial changes in number-line tasks.

Children display an early sensitivity to implicit proportions (e.g., 1 of 5 apples vs 3 of 4 apples) but have considerabledifficulty in learning the explicit, symbolic proportions denoted by fractions (e.g., 1/5 vs 3/4). Theoretically, reducingthe gap between representations of implicit vs explicit proportions would improve understanding of fractions, but littleis known about how the representations develop and interact with one another. To address this, we asked 163 third tofifth graders to estimate the position of proportionally-equivalent integers and fractions on number lines (e.g., 3 on 0-8number line vs 3/8 on 0-1 number line). We found that, with increasing age, children were more accurate and linear inrepresenting both integers and fractions. More importantly, childrens estimates of implicit and explicit proportions becamemore coherent, such that a childs estimates of fractions on a 0-1 number-line was a linear function of the same childsestimates of equivalent integers. This representational coherence independently predicted childrens fraction proficiency inother tasks, suggest- ing that building a coherent understanding of proportions is an educationally-important goal.

In a conventional number-line task, a given number that varies every trial is estimated on a line flanked with 0 and anupper-bound number. An upper-bound number is often arbitrarily selected, although this design variable has been shownto affect non-linearity in estimates. Examining estimates of varying given numbers (design variable 1) with varying upper-bound numbers (design variable 2) can be costly because adding another design variable into the task drastically increasesthe number of trials required to examine the numerical representation. In the present study, a novel Bayesian machinelearning algorithm, dubbed Gaussian Process Active Learning (GPAL), was used to make this costly paradigm feasible bypresenting only the most informative combinations of the design variables every trial. We found that children were morelogarithmic than adults across upper bounds, replicating log-to-linear shifts in development. More importantly, childrenand even educated adults became more logarithmic as the upper bound increased, indicating the persistent use of logrepresentation across age groups.

PurposeTo report the outcome of a previously vitrectomized eye having less lymphoma disease burden compared with the contralateral nonvitrectomized eye over the course of 3.5 years while on systemic chemotherapy.MethodsCase report.ResultsA 51-year-old man with vitreoretinal lymphoma with central nervous system involvement underwent vitrectomy in his left eye. Over the following 3.5 years on systemic chemotherapy, the left eye had less lymphoma disease burden compared with the contralateral nonvitrectomized right eye.ConclusionTherapeutic vitrectomy may be a useful adjunct to systemic chemotherapy in vitreoretinal lymphoma, particularly in cases of vitreous predominant disease manifestation.