Stable oxygen and carbon isotope compositional fields for skeletal and diagenetic components in New Zealand Cenozoic nontropical carbonate sediments and limestones: a synthesis and review

The stable oxygen isotope composition (d¹⁸O) of a precipitated carbonate depends mainly on the isotope composition, salinity, and temperature of the host fluid, whereas the stable carbon isotope composition (d¹³C) reflects the source of CO2 for precipitation, such as meteoric or sea water, shell dissolution, or various biochemical origins, including microbial oxidation of organic matter and methane. Despite the potentially complex array of controls, natural waters tend to show a characteristic range of isotope values which in turn are mimicked or tracked by the carbonate minerals precipitated from them. Consequently, plots of d¹⁸O versus d¹³C for carbonate materials can help identify their depositional and/or diagenetic environment(s)

Stable isotope values in modern bryozoan carbonate from New Zealand and implications for paleoenvironmental interpretation

Bryozoan carbonate contains useful geochemical evidence of temperate shelf paleoenvironments. Stable isotope values were determined for 103 modern marine bryozoan skeletons representing 30 species from New Zealand. δ18O values range from -1.4 to 2.8 VPDB, while δ13C range from -4.5 to 2.8 VPDB (values uncorrected for mineralogical variation). These values are distinct from those of both tropical marine skeletons and New Zealand Tertiary fossils. Most bryozoans secrete carbonate in or near isotopic equilibrium with sea water, except for Celleporina and Steginoporella. The complex and variable mineralogies of the bryozoans reported here make correction for mineralogical effects problematic. Nevertheless, mainly aragonitic forms display higher isotope values, as anticipated. Both temperature and salinity constrain δ18O and δ13C values, and vary with latitude and water depth. Ten samples from a single branch of Cinctipora elegans from the Otago shelf cover a narrow range, although the striking difference in carbon isotope values between the endozone and exozone probably reflects different mineralisation histories. Our stable isotope results from three different laboratories on a single population from a single location are encouragingly consistent. Monomineralic bryozoans, when carefully chosen to avoid species suspected of vital fractionation, have considerable potential as geochemical paleoenvironmental indicators, particularly in temperate marine environments where bryozoans are dominant sediment producers

Mineralogical Variation in Shells of the Blackfoot Abalone, Haliotis iris (Mollusca: Gastropoda: Haliotidae), in Southern New Zealand

The New Zealand blackfoot abalone, Haliotis iris Gmelin, is among the few gastropods that precipitate both calcite and aragonite in their shells. The location, composition, and thickness of these mineral layers may affect color, luster, and strength of the shell, which is locally important in jewelry manufacture. Skeletal mineralogy and shell structure of H. iris from three southern New Zealand locations were determined using X-ray diffractometry, scanning electron micrography, and mineral staining. In H. iris an outer calcitic layer is separated from an inner aragonitic surface by both calcified and noncalcified organic layers running longitudinally through the shell. Skeletal mineralogy within individual shells varies from 29 to 98% aragonite, with older shell having significantly higher aragonite content than young sections. Variation within populations ranges from 40 to 98% aragonite, and among three populations from 34 to 98% aragonite. Shell thickness, too, varies within individual shells from 0.2 to 4.2 mm, with a significant positive relationship with age. Within population variation in shell thickness ranges from 2.1 to 5.4 mm, with no significant difference in shell thickness variation among populations. The high degree of variability within and among individual shells suggests that it is essential to test replicate samples from individual mollusk shells, especially when they have complex bimineral structure

Non-Traditional and Non-Invasive Approaches in Facial Rejuvenation: A Brief Review

While injectables, lasers, and surgical interventions have traditionally been used to reverse the changes associated with facial aging, other alternative therapies such as facial acupuncture and facial exercises are now being studied for facial rejuvenation. In this paper, we both summarize the concepts of facial acupuncture and facial exercises, and review seven studies that evaluate the efficacy of these modalities. Data from these studies suggest that both facial acupuncture and facial exercises have the potential to improve the skin laxity, wrinkle length, muscle thickness, and pigmentary changes associated with aging. Patients frequently reported improvement and experienced very few side effects. However, further research is necessary before these modalities are widely accepted as eective by the medical community, though the results of these studies may ultimately make providers less hesitant when patients seek out these services

Non-Traditional and Non-Invasive Approaches in Facial Rejuvenation: A Brief Review

While injectables, lasers, and surgical interventions have traditionally been used to reverse the changes associated with facial aging, other alternative therapies such as facial acupuncture and facial exercises are now being studied for facial rejuvenation. In this paper, we both summarize the concepts of facial acupuncture and facial exercises, and review seven studies that evaluate the efficacy of these modalities. Data from these studies suggest that both facial acupuncture and facial exercises have the potential to improve the skin laxity, wrinkle length, muscle thickness, and pigmentary changes associated with aging. Patients frequently reported improvement and experienced very few side effects. However, further research is necessary before these modalities are widely accepted as effective by the medical community, though the results of these studies may ultimately make providers less hesitant when patients seek out these services

Benefactors, Bonds, and Beholders: The Beliefs and Reality Behind Beethoven’s Behavior

This paper will explore the relationships which Beethoven had during the years he composed and premiered his Eroica Symphony. Some of the individuals who will be discussed in this paper include Prince Lobkowitz, Ferdinand Ries, and Franz Wegeler. After learning about the nature of these relationships, the reader should begin to realize that Beethoven’s notoriously irrational or ill-tempered behavior was only one facet of his life

Sulfate Enhances the Adsorption and Retention of Cu(II) and Zn(II) to Dispersed and Aggregated Iron Oxyhydroxide Nanoparticles

The adsorption and retention of metal ions to nanoscale iron (hydr)oxides in aqueous systems is significantly influenced by prevailing environmental conditions. We examined the influence of sulfate, the second most common anion in seawater that is present in many other natural aquatic systems, on the adsorption and retention of Cu(II) and Zn(II) to synthetic iron oxyhydroxide nanoparticles (NPs) and their aggregates. Batch uptake experiments with monodisperse NPs and NPs aggregated by changes in pH, ionic strength, and temperature were conducted over sulfate concentrations ranging from 0 to 0.30 M. The introduction of 0.03 M sulfate significantly increased the initial adsorption and retention of Zn(II) and Cu(II) compared to sulfate-free conditions; with increasing sulfate \u3e0.03 M, Zn(II) retention continuously increased, while Cu(II) retention was considerably more variable but increased slightly. NP aggregation, when induced by pH and ionic strength, was positively correlated with metal ion retention, while aggregation temperature was negatively correlated with both adsorption and retention. Aqueous geochemical modeling indicated that Zn(II) readily complexes with sulfate to form ZnSO4 (aq), but that stable aqueous CuSO4 species are uncommon. EXAFS spectroscopic analysis suggests structural incorporation of Zn(II) and Zn(II)-sulfate ternary surface complexation, while Cu(II) primarily forms inner-sphere bidentate surface complexes. Collectively, the effects of sulfate in both reducing surface charge repulsion, initiating ternary surface complexation, and enabling structural incorporation aid to enhance both metal adsorption and retention to iron oxyhydroxide NPs and their aggregates

An Up-Close Look at Student-Centered Math Teaching: A Study of Highly Regarded High School Teachers and Their Students - Executive Summary

Today, far too many students see mathematics as a subject to be endured, rather than a subject of real-world importance and personal value. That doesn't have to be the case. When teachers use student-centered techniques to engage studentsin more active and authentic ways, they can transform math classrooms into lively learning environments in which studentstake charge of their own learning, collaborate with others, persist in solving complex problems, and make meaningfulconnections to the world around them. Through such experiences, students may come to appreciate mathematics as adiscipline that enriches their lives and their understanding of the world.While a growing body of research supports many of the principles of student-centered instruction, there is still a great dealto learn about how such approaches enhance student learning in mathematics. Recent calls for strengthening the STEMworkforce and for more rigorous K-12 standards via the Common Core State Standards have placed increased emphasison developing higher-order thinking and problem-solving skills in high school mathematics, heightening the need for moreinformation about how teachers can effectively engage students with math content.The American Institutes of Research (AIR), with support from the Nellie Mae Education Foundation, conducted a study ofhighly regarded high school math teachers to expand the research base in two important ways. First, rather than assumingstudent-centered instruction is a monolithic construct, the team used a case study approach to provide rich descriptions ofhow the approach plays out in several classrooms, taking into account how teachers' personal philosophy and the school'sinstructional context might influence their practice. The case study also provided insights into students' perspectives on different approaches to mathematics instruction. Second, the researchers look across a larger sample of classrooms to determine the effects of varying degrees of student-centeredness on students' engagement with learning and their problem-solving skills.This brief offers highlights from the study's design and findings. Readers are encouraged to access the full paper for more details

The impact of believing you have had COVID-19 on self-reported behaviour: Cross-sectional survey.

OBJECTIVES: To investigate whether people who think they have had COVID-19 are less likely to report engaging with lockdown measures compared with those who think they have not had COVID-19. DESIGN: On-line cross-sectional survey. SETTING: Data were collected between 20th and 22nd April 2020. PARTICIPANTS: 6149 participants living in the UK aged 18 years or over. MAIN OUTCOME MEASURES: Perceived immunity to COVID-19, self-reported adherence to social distancing measures (going out for essential shopping, nonessential shopping, and meeting up with friends/family; total out-of-home activity), worry about COVID-19 and perceived risk of COVID-19 to oneself and people in the UK. Knowledge that cough and high temperature / fever are the main symptoms of COVID-19. We used logistic regression analyses and one-way ANOVAs to investigate associations between believing you had had COVID-19 and binary and continuous outcomes respectively. RESULTS: In this sample, 1493 people (24.3%) thought they had had COVID-19 but only 245 (4.0%) reported having received a positive test result. Reported test results were often incongruent with participants' belief that they had had COVID-19. People who believed that they had had COVID-19 were: more likely to agree that they had some immunity to COVID-19; less likely to report adhering to lockdown measures; less worried about COVID-19; and less likely to know that cough and high temperature / fever are two of the most common symptoms of COVID-19. CONCLUSIONS: At the time of data collection, the percentage of people in the UK who thought they had already had COVID-19 was about twice the estimated infection rate. Those who believed they had had COVID-19 were more likely to report leaving home. This may contribute to transmission of the virus. Clear communications to this growing group are needed to explain why protective measures continue to be important and to encourage sustained adherence

Identifying Farming Strategies Associated With Achieving Global Agricultural Sustainability

Sustainable agroecosystems provide adequate food while supporting environmental and human wellbeing and are a key part of the United Nations Sustainable Development Goals (SDGs). Some strategies to promote sustainability include reducing inputs, substituting conventional crops with genetically modified (GM) alternatives, and using organic production. Here, we leveraged global databases covering 121 countries to determine which farming strategies—the amount of inputs per area (fertilizers, pesticides, and irrigation), GM crops, and percent agriculture in organic production—are most correlated with 12 sustainability metrics recognized by the United Nations Food and Agriculture Organization. Using quantile regression, we found that countries with higher Human Development Indices (HDI) (including education, income, and lifespan), higher-income equality, lower food insecurity, and higher cereal yields had the most organic production and inputs. However, input-intensive strategies were associated with greater agricultural greenhouse gas emissions. In contrast, countries with more GM crops were last on track to meeting the SDG of reduced inequalities. Using a longitudinal analysis spanning 2004–2018, we found that countries were generally decreasing inputs and increasing their share of agriculture in organic production. Also, in disentangling correlation vs. causation, we hypothesize that a country's development is more likely to drive changes in agricultural strategies than vice versa. Altogether, our correlative analyses suggest that countries with greater progress toward the SDGs of no poverty, zero hunger, good health and wellbeing, quality education, decent work, economic growth, and reduced inequalities had the highest production of organic agriculture and, to a lesser extent, intensive use of inputs