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Technical note: how accurate can stalagmite formation temperatures be determined using vapour bubble radius measurements in fluid inclusions?
Stalagmites are natural archives containing detailed information on continental climate variability of the past. Microthermometric measurements of fluid inclusion homogenisation temperatures allow determination of stalagmite formation temperatures by measuring the radius of stable laser-induced vapour bubbles inside the inclusions. A reliable method for precisely measuring the radius of vapour bubbles is presented. The method is applied to stalagmite samples for which the formation temperature is known. An assessment of the bubble radius measurement accuracy and how this error influences the uncertainty in determining the formation temperature is provided. We demonstrate that the nominal homogenisation temperature of a single inclusion can be determined with an accuracy of ±0.25 °C, if the volume of the inclusion is larger than 105 μm3. With this method, we could measure in a proof-of-principle investigation that the formation temperature of 10–20 yr old inclusions in a stalagmite taken from the Milandre cave is 9.87 ± 0.80 °C, while the mean annual surface temperature, that in the case of the Milandre cave correlates well with the cave temperature, was 9.6 ± 0.15 °C, calculated from actual measurements at that time, showing a very good agreement. Formation temperatures of inclusions formed during the last 450 yr are found in a temperature range between 8.4 and 9.6 °C, which corresponds to the calculated average surface temperature. Paleotemperatures can thus be determined within ±1.0 °C
A Lesson Study on Teaching Impulse and Momentum in the New Normal
Impulse and momentum are basic concepts of mechanics introduced in the K to 12 curricula. Despite its basic concepts, students still have difficulties understanding the topic, especially when they are out of school due to the pandemic. After reopening the gates for face–to–face classes in the Philippines, the researchers found a significant reason to conduct a lesson study to improve teaching strategies on the topic. Lesson study is a development process wherein teachers work collaboratively to improve teachers teaching capacity. This study was conducted at Plaridel National High School with 23 participants from Grade 9 Newton (Set A and B). The research was conducted in two cycles using a four – phase lesson study. The research lesson was implemented using a 4A Model lesson plan and the results were taken from the analysis of the lesson study observation sheets, along with the class proficiency level. The researchers used the following strategies to improve teaching, namely; (1) showing mastery of subject matter, (2) reviewing basic mathematical operations, (3) contextualizing the lesson, (4) allowing students to answer questions in mother tongue, (5) using collaborative activities, (6) giving rewards, and (7) applying proper time management. However, the findings still showed that both sets of students achieved beginning proficiency level. Despite the implementation of these strategies, the students still lack basic knowledge of the topic and mathematical operations, and they struggle to understand it. Thus, it is recommended to plan the lesson effectively, utilize other research instruments, and collect feedback from the students
Internal stress as a link between macroscale and mesoscale mechanics
The internal (or residual) stress is among the key notions to describe the
state of the systems far from equilibrium. Such stress is invisible on the
macroscopic scale where the system is regarded as a blackbox. Yet
nonequilibrium macroscopic operations allow to create and observe the internal
stress. We present in this lecture some examples of the internal stress and its
operations. We describe the memory effect in some detail, the process in which
the history of past operations is recalled through the relaxation of internal
stress.Comment: 11pages, 2 figures, 7 equations: Refereed notes of the Lectures given
at "Morphogenesis through the interplay of nonlinear chemical instabilities
and elastic active media" July 2-14 2007. to be published from Springer (NATO
series
Non-Adherence in Patients on Peritoneal Dialysis: A Systematic Review
Background: It has been increasingly recognized that non-adherence is an important factor that determines the outcome of peritoneal dialysis (PD) therapy. There is therefore a need to establish the levels of non-adherence to different aspects of the PD regimen (dialysis procedures, medications, and dietary/fluid restrictions). Methods: A systematic review of peer-reviewed literature was performed in PubMed, PsycINFO and CINAHL databases using PRISMA guidelines in May 2013. Publications on non-adherence in PD were selected by two reviewers independently according to predefined inclusion and exclusion criteria. Relevant data on patient characteristics, measures, rates and factors associated with non-adherence were extracted. The quality of studies was also evaluated independently by two reviewers according to a revised version of the Effective Public Health Practice Project assessment tool. Results: The search retrieved 204 studies, of which a total of 25 studies met inclusion criteria. Reported rates of nonadherence varied across studies: 2.6 1353% for dialysis exchanges, 3.9 1385% for medication, and 14.4 1367% for diet/fluid restrictions. Methodological differences in measurement and definition of non-adherence underlie the observed variation. Factors associated with non-adherence that showed a degree of consistency were mostly socio-demographical, such as age, employment status, ethnicity, sex, and time period on PD treatment. Conclusion: Non-adherence to different dimensions of the dialysis regimen appears to be prevalent in PD patients. There is a need for further, high-quality research to explore these factors in more detail, with the aim of informing intervention designs to facilitate adherence in this patient populatio
The efficacy of stored human urine as an alternative fertilizer to the growth and development of Abelmoschus esculentus (Okra)
Fertilizers are commonly termed as any organic or inorganic material that is being added to the soil of the plant to supply for the nutrients that are essential to the growth of the plant. Nitrogen (N), Phosphorus (P), and Potassium (K) are the macronutrients that commonly make up the majority of the components in fertilizers. Human urine is mostly comprised of a plant’s essential nutrients, containing a significant amount of NPK similar to commercially known fertilizers. This research paper studied on how much human urine can be of convenience when used as fertilizers by measuring the plant’s growth and development, and specifically focused on the significant differences in the human urine components and the effects of its growth when stored and diluted for varied hours, specifically for 24 hours, 48 hours, and 72 hours. In this study, soil analysis was conducted to determine the plant’s NPK count, and was carried out after the fertilizer treatments. The NPK content found in the soil had shown some changes and correlation in its amount of composition. It was observed that, overtime, the concentration of N and P was decreased, and at the same time, there was a slight increase in the Phosphorus content. The amount of Potassium affects the photosynthetic abilities of a plant, therefore showing an increase in its growth. The results showed how much diluted human urine when stored for 72 hours can be of most benefit to the plant’s essential nutrients when compared to the others, and also showed the relation between the different treatments when stored for a varied amount of hours
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