Post-collection acidification of spot urine sample is not needed before measurement of electrolytes

IntroductionKidney stone formers can have higher oxalate and phosphate salt amounts in their urine than healthy people and we hypothesized that its acidification may be useful. The study aims to compare results of urine concentrations of calcium, magnesium, and inorganic phosphorus in the midstream portion of first voided morning urine samples without (FMU) and with post-collection acidification (FMUa) in kidney stone patients.Materials and methodsThis is a prospective single center study. A total of 138 kidney stone patients with spot urine samples were included in the study. Urine concentrations of calcium, magnesium and inorganic phosphorus were measured with and without post-collection acidification. Acidification was performed by adding 5 µL of 6 mol/L HCl to 1 mL of urine.ResultsThe median age (range) of all participants was 56 (18-87) years. The median paired differences between FMU and FMUa concentrations of calcium, magnesium, and inorganic phosphorus were: - 0.040 mmol/L, 0.035 mmol/L, and 0.060 mmol/L, respectively. They were statistically different: P < 0.001, P < 0.001, P = 0.004, respectively. These differences are not clinically significant because biological variations of these markers are much higher.ConclusionsNo clinically significant differences in urinary calcium, magnesium, and inorganic phosphorus concentrations between FMU and FMUa in patients with kidney stones were found.     

Young children's adaptive partner choice in cooperation and competition contexts

Choosing adequate partners is essential for cooperation, but how children calibrate their partner choice to specific social challenges is unknown. In two experiments, 4- to 7-year-olds (N = 189, 49% girls, mostly White, data collection: 03.2021–09.2022) were presented with partners in possession of different positive qualities. Children then recruited partners for hypothetical tasks that differed with respect to the quality necessary for success. Children and the selected partner either worked together toward a common goal or competed against each other. From age 5, children selectively chose individuals in possession of task-relevant qualities as cooperative partners while avoiding them as competitors. Younger children chose partners indiscriminately. Children thus learn to strategically adjust their partner choice depending on context-specific task demands and different social goals.     

Developmental and Educational Perspectives on Theory Change: To Have and Hold,or To Have and Hone?

Eric Schwitzgebel presents an attractive argument for the use of affective indicators to both assess and extend the 'theory theory' research agenda. A key component of his argument is an account of explanation that can be applied to both children and adults, few of whom possess the attributes and behaviors that warrant being called scientists. The core features of his account include 1) regarding a set of propositions as a theory and 2) subscribing to a theory by accepting and employing this set of propositions to explain events within the theory's domain. We will argue that this account, while potentially helpful for guiding research on the affective content of explanations, requires elaboration because it (1) does not fully characterize what is distinctive and important about theoretical and scientific thinking, (2) raises questions about different kinds of explanations, such as seen in transitions from common-sense explanations to theoretical explanations; (3) favors individual theorizing to the exclusion of socially mediated theorizing, and (4) raises developmental questions about the nature of explanation-seeking and the capacity to apply evidence to evaluate theories.     

Validation of the Career Adapt-Abilities Scale–Short Form across different age groups in the Turkish context

A short 12-item version of the Career Adapt-Abilities Scale–Short Form (CAAS-SF) was validated across three different age groups in the Turkish context. Scale scores demonstrated adequate to high internal consistency and 4-week test–retest reliability, good fit with the original four-factor model, factorial invariance across gender and age groups, strong convergence with the 24-item version, negative associations with trait anxiety and work stress, and positive associations with career decision self-efficacy. It was concluded that the Turkish version of the CAAS-SF appears to be a valid and reliable measure for assessing career adaptability and using it in career education and counseling process.     

Costs on the Mind: The Influence of the Financial Burden of College on Academic Performance and Cognitive Functioning

The current studies test the hypothesis that the financial burden of college can initiate a psychological process that has a negative influence on academic performance for students at selective colleges and universities. Prior studies linking high college costs and student loans to academic outcomes have not been grounded within relevant social psychological theory regarding how and when the financial burden of college can influence students’ psychological and cognitive processes. We test the hypothesis that the salient financial burden of college impairs students’ cognitive functioning, especially when it creates an identity conflict or perceived barrier to reaching a student’s desired financially successful future. First, we use longitudinal data from 28 selective colleges and universities to establish that students who accumulate student loan debt within these contexts are less likely to graduate from college because student loan debt predicts a decline in grades over time, even when controlling for factors related to socioeconomic status and prior achievement. Then, in an experiment, we advance research in this area with a direct, causal test of the proposed psychological process. An experimental manipulation that brings high college costs to mind impairs students’ cognitive functioning, but only when those thoughts create an identity conflict or a perceived barrier to reaching a student’s desired financially successful future.     

Optimal stabilization for differential systems with delays - Malkin’s approach

The paper considers a process controlled by a system of delayed differential equations. Under certain assumptions, a control function is determined such that the zero solution of the system is asymptotically stable and, for an arbitrary solution, the integral quality criterion with infinite upper limit exists and attains its minimum value in a given sense. To solve this problem, Malkin’s approach to ordinary differential systems is extended to delayed functional differential equations, and Lyapunov’s second method is applied. The results are illustrated by examples, and applied to some classes of delayed linear differential equations.     

Modified State Equations to Represent Changes in RC-Nullor Networks

Linear active networks are modeled as RC-Nullor networks. This makes available nodal analysis. The state equations of an RC-Nullor network are related to the node equations. This relationship is used to show how the state equations of an RC-Nullor network should be modified when the network is changed, e.g. by connecting a resistor between two nodes of the network. This is of interest because the network poles can be obtained from the state equations of the network, hence changes can be found in the network poles due to changes in the network.