Determinants of environmental degradation: reflections on the impact of identified economic variables on the environment

Purpose. The main objective of this study is to investigate the determinants of environmental degradation within the broader framework of the environmental Kuznets Curve analysis. To better understand the economic impact on the environment, the study focuses on the relationship between carbon emission and the variables income per capita, trade openness, foreign direct investment, energy use and urbanization. Methods. In the context of the dynamic carbon emission model a Generalized-Method-of-Moments (GMM) technique was used to analyse World Bank of 125 countries for the period 2000 to 2014. This era was chosen as the most appropriate given the completeness of the dataset. Findings. The findings indicate that economic growth and energy use are significant variables in explaining environmental degradation, supporting previous research in to the particularly negative impact of energy use on the environment. The research however, found that urbanisation had only marginal significance in explaining the impact on the environment. Originality. The findings contribute to existing research in the area of environmental degradation, providing insight into the debate surrounding urbanisation and CO2 emission which had previously received mixed results. The findings take research forward through the examination of explanatory variables and their respective impact on CO2 emission in countries which have observed an increase in the number of urban dwellers. Practical implications. Given the debate in academic and practitioner literature around climate change, pollution and a general concern over a lack of collective action to address environmental concerns, the findings have practical implications for government institutions and businesses to better understand the economic impact on the environment.Мета. Визначення факторів, які викликають екологічну деградацію довкілля в широкому контексті екологічної кривої Кузнеця, на основі вивчення взаємозв’язку між вуглецевими викидами і такими змінними як дохід на душу населення, відкритість торгівлі, прямі іноземні інвестиції, використання енергії та урбанізація. Методика. Для побудови динамічної моделі вуглецевої емісії були використані дані Всесвітнього банку по 125 країнам у період з 2000 по 2014 роки, проаналізовані за допомогою узагальненого методу моментів. Даний проміжок часу був обраний як той, що найбільш повно представляє базу даних. Результати. Встановлено, що економічне зростання і використання енергії є найсуттєвішими факторами, які визначають екологічну деградацію, що підтверджується більш ранніми дослідженнями негативного впливу використання енергії на навколишнє середовище. Виявлено, що урбанізація впливає на стан навколишнього середовища тільки побічно. Рекомендовано в наступних дослідженнях розглянути інші заходи для уявлення урбанізації, а саме можливість вивчення даних по великих містах, а не по країнам. Такий підхід може дати додаткове уявлення про вплив урбанізації та можливих відмінностей між містами і регіонами. Наукова новизна. Отримано нові знання щодо оцінки впливу урбанізації та вуглецевих викидів на навколишнє природне середовище, які раніше мали неоднозначні результати. Прогрес у вивченні даних проблем було досягнуто за рахунок аналізу ключових змінних і їх впливу на емісію CO2 в країнах, де спостерігається зростання міського населення. Практична значимість. Результати дослідження мають істотне практичне значення для державних установ та бізнесових структур, оскільки допомагають краще зрозуміти сутність економічного впливу на навколишнє середовище і вносять вклад у вирішення проблеми екологічної деградації.Цель. Определение факторов, вызывающих экологическую деградацию окружающей среды в широком контексте экологической кривой Кузнеца, на основе изучения взаимосвязи между углеродными выбросами и такими переменными как доход на душу населения, открытость торговли, прямые иностранные инвестиции, использование энергии и урбанизация. Методика. Для построения динамической модели углеродной эмиссии были использованы данные Всемирного банка по 125 странам в период с 2000 по 2014 годы, проанализированные при помощи обобщенного метода моментов. Данный промежуток времени был выбран как наиболее полно представляющий базу данных. Результаты. Установлено, что экономический рост и использование энергии являются самыми существенными факторами, определяющими экологическую деградацию, что подтверждается более ранними исследованиями негативного влияния использования энергии на окружающую среду. Выявлено, что урбанизация воздействует на состояние окружающей среды только косвенно. Рекомендовано в следующих исследованиях рассмотреть другие меры для представления урбанизации, а именно возможность изучения данных по крупным городам, а не по странам. Такой подход может дать дополнительное представление о влиянии урбанизации и возможных различий между городами и регионами. Научная новизна. Получены новые знания касательно оценки влияния урбанизации и углеродных выбросов на окружающую природную среду, которые ранее имели неоднозначные результаты. Прогресс в изучении данных проблем был достигнут за счет анализа ключевых переменных и их влияния на эмиссию CO2 в странах, где наблюдается рост городского населения. Практическая значимость. Результаты исследования имеют существенное практическое значение для государственных учреждений и бизнес структур, поскольку помогают лучше понять сущность экономического воздействия на окружающую среду и вносят вклад в решение проблемы экологической деградации.The authors would like to thank Taylor’s University for funding this research project (Source of funding: TRGS (Taylor’s Research Grant Scheme); Grant Project Code: TRGS/ERFS/1/2018/TBS/009)

The PL calibration for Milky Way Cepheids and its implications for the distance scale

The rationale behind recent calibrations of the Cepheid PL relation using the Wesenheit formulation is reviewed and reanalyzed, and it is shown that recent conclusions regarding a possible change in slope of the PL relation for short-period and long-period Cepheids are tied to a pathological distribution of HST calibrators within the instability strip. A recalibration of the period-luminosity relation is obtained using Galactic Cepheids in open clusters and groups, the resulting relationship, described by log L/L_sun = 2.415(+-0.035) + 1.148(+-0.044)log P, exhibiting only the moderate scatter expected from color spread within the instability strip. The relationship is confirmed by Cepheids with HST parallaxes, although without the need for Lutz-Kelker corrections, and in general by Cepheids with revised Hipparcos parallaxes, albeit with concerns about the cited precisions of the latter. A Wesenheit formulation of Wv = -2.259(+-0.083) - 4.185(+-0.103)log P for Galactic Cepheids is tested successfully using Cepheids in the inner regions of the galaxy NGC 4258, confirming the independent geometrical distance established for the galaxy from OH masers. Differences between the extinction properties of interstellar and extragalactic dust may yet play an important role in the further calibration of the Cepheid PL relation and its application to the extragalactic distance scale.Comment: Accepted for Publication (Astrophysics & Space Science

New Trends and Future Opportunities in the Enzymatic Formation of C-C, C-N, and C-O bonds

Organic chemistry provides society with fundamental products we use daily. Concerns about the impact that the chemical industry has over the environment is propelling major changes in the way we manufacture chemicals. Biocatalysis offers an alternative to other synthetic approaches as it employs enzymes, Nature''s catalysts, to carry out chemical transformations. Enzymes are biodegradable, come from renewable sources, operate under mild reaction conditions, and display high selectivities in the processes they catalyse. As a highly multidisciplinary field, biocatalysis benefits from advances in different areas, and developments in the fields of molecular biology, bioinformatics, and chemical engineering have accelerated the extension of the range of available transformations (E. L. Bell et al., Nat. Rev. Meth. Prim. 2021, 1, 1–21). Recently, we surveyed advances in the expansion of the scope of biocatalysis via enzyme discovery and protein engineering (J. R. Marshall et al., Tetrahedron 2021, 82, 131926). Herein, we focus on novel enzymes currently available to the broad synthetic community for the construction of new C-C, C-N and C-O bonds, with the purpose of providing the non-specialist with new and alternative tools for chiral and sustainable chemical synthesis. © 2021 The Authors. ChemBioChem published by Wiley-VCH GmbH

Exponential-Potential Scalar Field Universes I: The Bianchi I Models

We obtain a general exact solution of the Einstein field equations for the anisotropic Bianchi type I universes filled with an exponential-potential scalar field and study their dynamics. It is shown, in agreement with previous studies, that for a wide range of initial conditions the late-time behaviour of the models is that of a power-law inflating FRW universe. This property, does not hold, in contrast, when some degree of inhomogeneity is introduced, as discussed in our following paper II.Comment: 16 pages, Plain LaTeX, 1 Figure to be sent on request, to appear in Phys. Rev.

Stability analysis and break-up length calculations for steady planar liquid jets

This study uses spatio-temporal stability analysis to investigate the convective and absolute instability properties of a steady unconfined planar liquid jet. The approach uses a piecewise linear velocity profile with a finite-thickness shear layer at the edge of the jet. This study investigates how properties such as the thickness of the shear layer and the value of the fluid velocity at the interface within the shear layer affect the stability properties of the jet. It is found that the presence of a finite-thickness shear layer can lead to an absolute instability for a range of density ratios, not seen when a simpler plug flow velocity profile is considered. It is also found that the inclusion of surface tension has a stabilizing effect on the convective instability but a destabilizing effect on the absolute instability. The stability results are used to obtain estimates for the breakup length of a planar liquid jet as the jet velocity varies. It is found that reducing the shear layer thickness within the jet causes the breakup length to decrease, while increasing the fluid velocity at the fluid interface within the shear layer causes the breakup length to increase. Combining these two effects into a profile, which evolves realistically with velocity, gives results in which the breakup length increases for small velocities and decreases for larger velocities. This behaviour agrees qualitatively with existing experiments on the breakup length of axisymmetric jets

Improving adherence to acute low back pain guideline recommendations with chiropractors and physiotherapists: the ALIGN cluster randomised controlled trial

Background Acute low back pain is a common condition, has high burden, and there are evidence-to-practice gaps in the chiropractic and physiotherapy setting for imaging and giving advice to stay active. The aim of this cluster randomised trial was to estimate the effects of a theory- and evidence-based implementation intervention to increase chiropractors’ and physiotherapists’ adherence to a guideline for acute low back pain compared with the comparator (passive dissemination of the guideline). In particular, the primary aim of the intervention was to reduce inappropriate imaging referral and improve patient low back pain outcomes, and to determine whether this intervention was cost-effective. Methods Physiotherapy and chiropractic practices in the state of Victoria, Australia, comprising at least one practising clinician who provided care to patients with acute low back pain, were invited to participate. Patients attending these practices were included if they had acute non-specific low back pain (duration less than 3 months), were 18 years of age or older, and were able to understand and read English. Practices were randomly assigned either to a tailored, multi-faceted intervention based on the guideline (interactive educational symposium plus academic detailing) or passive dissemination of the guideline (comparator). A statistician independent of the study team undertook stratified randomisation using computer-generated random numbers; four strata were defined by professional group and the rural or metropolitan location of the practice. Investigators not involved in intervention delivery were blinded to allocation. Primary outcomes were X-ray referral self-reported by clinicians using a checklist and patient low back pain-specific disability (at 3 months). Results A total of 104 practices (43 chiropractors, 85 physiotherapists; 755 patients) were assigned to the intervention and 106 practices (45 chiropractors, 97 physiotherapists; 603 patients) to the comparator; 449 patients were available for the patient-level primary outcome. There was no important difference in the odds of patients being referred for X-ray (adjusted (Adj) OR: 1.40; 95% CI 0.51, 3.87; Adj risk difference (RD): 0.01; 95% CI − 0.02, 0.04) or patient low back pain-specific disability (Adj mean difference: 0.37; 95% CI − 0.48, 1.21, scale 0–24). The intervention did lead to improvement for some key secondary outcomes, including giving advice to stay active (Adj OR: 1.96; 95% CI 1.20, 3.22; Adj RD: 0.10; 95% CI 0.01, 0.19) and intending to adhere to the guideline recommendations (e.g. intention to refer for X-ray: Adj OR: 0.27; 95% CI 0.17, 0.44; intention to give advice to stay active: Adj OR: 2.37; 95% CI 1.51, 3.74). Conclusions Intervention group clinicians were more likely to give advice to stay active and to intend to adhere to the guideline recommendations about X-ray referral. The intervention did not change the primary study outcomes, with no important differences in X-ray referral and patient disability between groups, implying that hypothesised reductions in health service utilisation and/or productivity gains are unlikely to offset the direct costs of the intervention. We report these results with the caveat that we enrolled less patients into the trial than our determined sample size. We cannot recommend this intervention as a cost-effective use of resources

Nonsingular instantons for the creation of open universes

We show that the instability of the singular Vilenkin instanton describing the creation of an open universe can be avoided using, instead of a minimally coupled scalar field, an axionic massless scalar field which gives rise to the Giddings-Strominger instanton. However, if we replace the singularity of the Hawking Turok instanton for an axionic wormhole some interpretational and technical difficulties would appear which can be overcome by introducing a positive cosmological constant in the action. This would make the instanton finite and free constant in the action. This would make the instanton finite and free from any instabilities.Comment: 8 pages, RevTex. A new section on the instantonic global structure and a figure have been added. To appear in Phys. Rev.