Analysis of Natural Buffer Systems and the Impact of Acid Rain. An Environmental Project for First-Year Chemistry Students

2005 ◽  
Vol 82 (2) ◽  
pp. 274 ◽  
Author(s):  
David C. Powers ◽  
Andrew T. Higgs ◽  
Matt L. Obley ◽  
Phyllis A. Leber ◽  
Kenneth R. Hess ◽  
...  
Author(s):  
Caroline Z. Muteti ◽  
Carolina Zarraga ◽  
Brooke I. Jacob ◽  
Tuli M. Mwarumba ◽  
Dorothy B. Nkhata ◽  
...  

Many students transitioning from high school to college are faced with challenges of getting acclimated to college life and managing their time and heavy course load that is cognitively demanding. Students planning to major in science, technology, engineering, and mathematics (STEM) programs in the United States are mostly required to enroll in general chemistry courses as prerequisites. Unfortunately, these courses are among the STEM gateway courses in which many first-year students struggle to get through, or are weeded out. This is partly due to the use of ineffective study strategies that require more than rote memorization, a common learning approach in high schools. One way to prepare first-year college students for STEM trajectories is by teaching them metacognitive strategies early in their study programs to enable early adoption and sustainability of metacognition knowledge and metacognition regulation skills as they progress to the advanced courses. While a handful of studies have investigated study strategies among students in the general chemistry courses as well as the impact of metacognitive activities on student performance in chemistry, very few in-depth qualitative studies investigating the influence of explicit teaching of metacognition on students’ study strategies have been reported. Using open-ended questionnaires, this unique study investigated general chemistry students’ study strategies that they employed prior to a 50 minute metacognition lesson; strategies they reported to have gained from the instruction; and the influence of the metacognition instruction on students’ study strategies and performance in the final exam. Findings indicated more reported use of rote memorization over higher-order study strategies prior to the metacognition instruction, but more reported gains on higher-order study strategies and fewer strategies related to rote memorization immediately after the metacognition instruction. Furthermore, 67% reported a positive influence of the metacognition instruction on study strategies, with 7% lower DFs in the final exam compared to those who reported ‘no influence’. Findings revealed that most general chemistry students were unaware of effective study strategies; thus, there is a critical need to explicitly teach students in general chemistry courses metacognitive strategies.


2014 ◽  
Vol 15 (2) ◽  
pp. 184-191 ◽  
Author(s):  
S. J. Brown ◽  
B. N. Sharma ◽  
L. Wakeling ◽  
M. Naiker ◽  
S. Chandra ◽  
...  

The attitude towards the study of chemistry for new entrant chemistry students from a multi-national, regional, tertiary educational institution in the South Pacific was investigated using a purpose-designed diagnostic instrument. The Attitude toward the Study of Chemistry Inventory (ASCI) was used to quantify attitude in a cohort of first year undergraduate (n = 144) and foundation (n = 108) chemistry students. A similar, generally positive attitude to the study of chemistry was shown by both groups of students. Exploratory factor analysis using principle axis factoring and direct oblimin rotation was used to identify factors within the pooled data. Three factors accounted for more than 50% of the total variance, while Cronbach's alpha values for the factors 1, 2 and 3 were 0.92, 0.68 and 0.78, respectively. Factors 1 and 2 were consistent with known constructs of attitude, namely affective (factor 1) and cognitive (factor 2). However, the other factor (3) identified in this study was designated “Value”, which may reflect the students' choice of chemistry as a career path. ASCI may be a suitable tool for monitoring students' attitude throughout a degree and also to monitor the impact of novel approaches for teaching chemistry and engaging students.


2018 ◽  
Vol 19 (2) ◽  
pp. 543-557 ◽  
Author(s):  
Lisa Shah ◽  
Christian A. Rodriguez ◽  
Monica Bartoli ◽  
Gregory T. Rushton

Instructional strategies that support meaningful student learning of complex chemical topics are an important aspect of improving chemistry education. Adequately assessing the success of these approaches can be supported with the use of aligned instruments with established psychometrics. Here, we report the implementation and assessment of one such curriculum,Chemical Thinking, on first-year general chemistry students' conceptions of relative acidity using the recently-developed concept inventory,ACIDI. Our results reveal that, overall, students performed significantly better onACIDIfollowing instruction, with scores consistent with those previously reported for students who had completed one semester of organic chemistry. Students performed equally well on a delayed post-test administered ten weeks after final instruction, which suggests that instruction promoted a stable conceptual reprioritisation. Item analysis ofACIDIrevealed that students generally made conceptual gains on items where inductive effects were the primary determinants of conjugate base stability and relative acidity. However, students overwhelmingly struggled on items where resonance was the primary determinant. Analysis of student–student arguments in active learning settings provided evidence for how the quality of student arguments impacted their conceptions. Overall, these findings suggest that students were able to avoid several superficial misconceptions cited in the literature about relative acidity, and that this topic, traditionally taught exclusively in organic chemistry, may be introduced earlier in the sequence of curricular topics. Implications for future studies on the role of argumentational aspects of student–student conversations and facilitation strategies in promoting or hindering meaningful learning are discussed.


2014 ◽  
Vol 22 (4) ◽  
pp. 194-201 ◽  
Author(s):  
Freda-Marie Hartung ◽  
Britta Renner

Humans are social animals; consequently, a lack of social ties affects individuals’ health negatively. However, the desire to belong differs between individuals, raising the question of whether individual differences in the need to belong moderate the impact of perceived social isolation on health. In the present study, 77 first-year university students rated their loneliness and health every 6 weeks for 18 weeks. Individual differences in the need to belong were found to moderate the relationship between loneliness and current health state. Specifically, lonely students with a high need to belong reported more days of illness than those with a low need to belong. In contrast, the strength of the need to belong had no effect on students who did not feel lonely. Thus, people who have a strong need to belong appear to suffer from loneliness and become ill more often, whereas people with a weak need to belong appear to stand loneliness better and are comparatively healthy. The study implies that social isolation does not impact all individuals identically; instead, the fit between the social situation and an individual’s need appears to be crucial for an individual’s functioning.


Author(s):  
А. М. Grebennikov ◽  
А. S. Frid ◽  
V. P. Belobrov ◽  
V. А. Isaev ◽  
V. М. Garmashоv ◽  
...  

The article assesses the relationships between the morphological properties of agrochernozems and yield of peas on the plots, experience with different methods of basic treatment (moldboard plowing at the depth of 20 - 22, 25 - 27 and 14 - 16 cm, moldboard plowing to a depth of 14 - 16 cm, combined midwater moldboard, mid-water subsurface, surface to a depth of 6 - 8 cm and zero tillage) is inherent in V.V. Dokuchaev Research Institute of Agriculture of the Central Black Earth strip, in the fall of 2014. The research was conducted in 2015 - 2016, with the application of mineral fertilizers (N60Р60К60) and unfertilized background. The highest pea yields in the fertilized as the background, and without the use of fertilizers was observed in dumping plowing and especially in the variant with deep moldboard plowing, which creates in comparison with other ways of handling the best conditions for the growth and development of peas. The lowest yield of pea was obtained with zero processing. Apparently legalistic migrational-mizelial agrochernozems the Central Chernozem zone of minimum tillage in the cultivation of peas are not effective, what is evident already in the first year after the laying of experience with different basic treatments. As shown by the results of applying multifactor analysis of variance studied the mapping properties of the soil can have the same significant impact on the yield of agricultural crops, as options for the field experiments aimed at assessing the impact of various treatments on yield.


Author(s):  
Diarmaid Lane ◽  
Sheryl Sorby

AbstractIn recent years, there has been a surge in research in spatial thinking across the international community. We now know that spatial skills are malleable and that they are linked to success across multiple disciplines, most notably Science, Technology, Engineering and Mathematics (STEM). While spatial skills have been examined by cognitive scientists in laboratory environments for decades, current research is examining how these skills can be developed in field-based environments. In this paper, we present findings from a study within a Technology Teacher preparation programme where we examined first-year students’ spatial skills on entry to university. We explain why it was necessary to embed a spatial skills intervention into Year 1 of the programme and we describe the impact that this had on students’ spatial scores and on academic performance. The findings from our study highlight a consistent gender gap in spatial scores at the start of the first-year with female students entering the Technology Teacher preparation programme at a lower base level than male students. We describe how we integrated spatial development activities into an existing course and how an improvement in spatial scores and overall course performance was observed. The paper concludes by discussing the long-term sustainability of integrating spatial interventions within teacher preparation programmes while also highlighting the importance of future research to examine spatial skills as a fundamental component of technological capability.


Author(s):  
Alexander P. Parobek ◽  
Patrick M. Chaffin ◽  
Marcy H. Towns

Reaction coordinate diagrams (RCDs) are chemical representations widely employed to visualize the thermodynamic and kinetic parameters associated with reactions. Previous research has demonstrated a host of misconceptions students adopt when interpreting the perceived information encoded in RCDs. This qualitative research study explores how general chemistry students interpret points and trends on a RCD and how these interpretations impact their inferences regarding the rate of a chemical reaction. Sixteen students participated in semi-structured interviews in which participants were asked to interpret the points and trends along provided RCDs and to compare relative reaction rates between RCDs. Findings derived from this study demonstrate the diversity of graphical reasoning adopted by students, the impact of students’ interpretations of the x-axis of a RCD on the graphical reasoning employed, and the influence of these ideas on inferences made about reaction rate. Informed by analytical frameworks grounded in the resources framework and the actor-oriented model of transfer, implications for instruction are provided with suggestions for how RCDs may be presented to assist students in recognizing the critical information encoded in these diagrams.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Gerhard Müller ◽  
Manuela Bombana ◽  
Monika Heinzel-Gutenbrenner ◽  
Nikolaus Kleindienst ◽  
Martin Bohus ◽  
...  

Abstract Background Mental disorders are related to high individual suffering and significant socio-economic burdens. However, it remains unclear to what extent self-reported mental distress is related to individuals’ days of incapacity to work and their medical costs. This study aims to investigate the impact of self-reported mental distress for specific and non-specific days of incapacity to work and specific and non-specific medical costs over a two-year span. Method Within a longitudinal research design, 2287 study participants’ mental distress was assessed using the Hospital Anxiety and Depression Scale (HADS). HADS scores were included as predictors in generalized linear models with a Tweedie distribution with log link function to predict participants’ days of incapacity to work and medical costs retrieved from their health insurance routine data during the following two-year period. Results Current mental distress was found to be significantly related to the number of specific days absent from work and medical costs. Compared to participants classified as no cases by the HADS (2.6 days), severe case participants showed 27.3-times as many specific days of incapacity to work in the first year (72 days) and 10.3-times as many days in the second year (44 days), and resulted in 11.4-times more medical costs in the first year (2272 EUR) and 6.2-times more in the second year (1319 EUR). The relationship of mental distress to non-specific days of incapacity to work and non-specific medical costs was also significant, but mainly driven from specific absent days and specific medical costs. Our results also indicate that the prevalence of presenteeism is considerably high: 42% of individuals continued to go to work despite severe mental distress. Conclusions Our results show that self-reported mental distress, assessed by the HADS, is highly related to the days of incapacity to work and medical costs in the two-year period. Reducing mental distress by improving preventive structures for at-risk populations and increasing access to evidence-based treatments for individuals with mental disorders might, therefore, pay for itself and could help to reduce public costs.


2021 ◽  
Vol 10 (2) ◽  
pp. 296
Author(s):  
Imke Matthys ◽  
Justine Defreyne ◽  
Els Elaut ◽  
Alessandra Daphne Fisher ◽  
Baudewijntje P. C. Kreukels ◽  
...  

Improving transgender people’s quality of life (QoL) is the most important goal of gender-affirming care. Prospective changes in affect can influence QoL. We aim to assess the impact of initiating gender-affirming hormonal treatment (HT) on affect. In the European Network for the Investigation of Gender Incongruence (ENIGI) study, we prospectively collected data of 873 participants (451 transwomen (TW) and 422 transmen (TM)). At baseline, psychological questionnaires including the Positive and Negative Affect Schedule (PANAS) were administered. The PANAS, levels of sex steroids and physical changes were registered at each follow-up visit during a 3-year follow-up period, starting at the initiation of hormonal therapy. Data were analyzed cross-sectionally and prospectively. Over the first three months, we observed a decline in positive affect (PA) in both TM and TW. Thereafter, PA reached a steady state in TW, whereas in TM there was also a second decline at 18 months. In both TM and TW there was no persisting difference comparing baseline to the 36-months results. Concerning negative affect (NA), we observed a decline during the first year in TM, which sustained during the second year and was not different anymore at 36 months compared to baseline. In TW though, we did not find any change of NA during the entire follow-up. Even if some of these results show significant differences, they should be considered with caution, since there was no control group and the absolute differences are small. No association between affect and the level of sex steroids was observed. Baseline QoL and psychological burden are related to affect independently from gender but are not necessarily good predictors of the evolution of one’s affect during the gender-affirming process. Further research is necessary to investigate these preliminary results.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S551-S551
Author(s):  
Sneha Thatipelli ◽  
Chad Achenbach ◽  
Shannon Galvin

Abstract Background Integrase strand transfer inhibitors (InSTIs) as ART for HIV has been associated with clinically significant weight gain, in addition to the “return to health phenomenon”. Methods We conducted a cohort study on adults over 18 with HIV, who had baseline weights and an additional weight at least 6 months later. Individuals with malignancies, thyroid disorders, and disseminated tuberculosis or mycobacterium avium complex were excluded. To understand the impact of InSTIs on chronic vs. recently infected persons, we divided the cohort into four groups: (1) well-controlled on non-InSTI ART [WN] (2) well-controlled on InSTI ART [WI] (3) uncontrolled on non-InSTI ART [UN], and (4) uncontrolled on InSTI ART [UI]. Well-controlled persons (viral load < 2000) were proxies for chronic infection on long-term ART and uncontrolled for recently infected and initiated on ART. New diagnoses of diabetes, hyperlipidemia, and hypertension were determined by ICD10 codes. Participants with a weight change more than 10 kg in 6 months were excluded. Results 612 of the initial 910 participants in the cohort met the inclusion criteria. Comparing those who remained on the designated regimen throughout the study led to 86 WN, 153 WI, 166 UN, and 145 UI. Mean weight change at 6 months for WN was +0.22 kg (95% CI [-0.86, 1.3]), at 1 year was -0.86 kg (95% CI [-2.94, 1.22]), and at 2 years was +0.026 kg (95% CI [-2.347, 2.399]). For WI, mean weight change at 6 months was +0.21 kg (95% CI [-0.79, 1.21]), at 1 year was -0.50 kg (95% CI [-2.02, 1.04]), and at 2 years was +0.43 kg (95% CI [-1.35, 2.21]). UN gained weight until the first year (+1.74 kg at 6 mo (95% CI [0.24, 3.24]) and +3.84 kg at 1 year (95% CI [1.57, 6.11])), but plateaued at 2 years (+2.42 kg (95% CI [-0.44, 5.28])). At 6 months mean weight gain for UI was +0.78 kg (95% CI [-0.15, 1.71]), at 1 year was +2.33 kg (95% CI [1.02, 3.64]), and at 2 years was +3.04 kg (95% CI [1.2, 4.85]). WI had a higher incidence of diabetes (37% vs. 32%, p=0.40), hyperlipidemia (32% vs. 29%, p=0.66), and hypertension (34% vs. 26%, p=0.19) compared to WN. Conclusion InSTIs may confer a larger and more sustained weight gain among individuals in the first two years after ART initiation. Well controlled individuals did not have statistically significant weight change, but those on Insti-based ART had more metabolic diseases. Disclosures All Authors: No reported disclosures


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