scholarly journals Idealised simulations of cyclones with robust symmetrically-unstable sting jets

2019 ◽  
Author(s):  
Ambrogio Volonté ◽  
Peter A. Clark ◽  
Suzanne L. Gray
Keyword(s):  
Environmental Factors ◽  
Conceptual Model ◽  
Environmental Conditions ◽  
Positive Relationship ◽  
Initial State ◽  
Sensitivity Experiments ◽  
Fracture Region ◽  
Peak Speed ◽  
Symmetric Instability

Abstract. Idealised simulations of Shapiro-Keyser cyclones developing a sting jet (SJ) are presented. Thanks to an improved and accurate implementation of thermal wind balance in the initial state, it has been possible to use more realistic environments than in previous idealised studies. As a consequence, this study provides further insight in SJ evolution and dynamics and explores SJ robustness to different environmental conditions, assessed via a wide and different range of sensitivity experiments. The control simulation contains a cyclone that fits the Shapiro-Keyser conceptual model and develops a SJ whose dynamics are associated with the evolution of mesoscale instabilities including symmetric instability (SI) along the airstream. The SJ undergoes a strong descent while leaving the cloud-head banded tip and markedly accelerating towards the frontal-fracture region, revealed as an area of buckling of the already-sloped moist isentropes. A substantial amount of SI, generated by slantwise frontal motions in the cloud head, is released along the SJ during its descent. This supports the role of SI in the airstream’s dynamics proposed in a conceptual model outlined in a previous study. Sensitivity experiments illustrate that the SJ is a robust feature of intense Shapiro-Keyser cyclones, highlighting a range of different environmental conditions in which SI contributes to the evolution of this airstream, conditional on the model having adequate resolution. The results reveal that several environmental factors can modulate the strength of the SJ. However, a positive relationship between the strength of the SJ, both in terms of peak speed and amount of descent, and the amount of instability occurring along it can still be identified. In summary, the idealised simulations presented in this study show the robustness of SJ occurrence in intense Shapiro-Keyser cyclones and support and clarify the role of dry instabilities in SJ dynamics.

scholarly journals Idealised simulations of cyclones with robust symmetrically unstable sting jets

2020 ◽  
Vol 1 (1) ◽  
pp. 63-91 ◽  
Author(s):  
Ambrogio Volonté ◽  
Peter A. Clark ◽  
Suzanne L. Gray
Keyword(s):  
Conceptual Model ◽  
Environmental Conditions ◽  
Positive Relationship ◽  
Initial State ◽  
Sensitivity Experiments ◽  
Fracture Region ◽  
Wide Range ◽  
Peak Speed ◽  
Insight Into

Abstract. Idealised simulations of Shapiro–Keyser cyclones developing a sting jet (SJ) are presented. Thanks to an improved and accurate implementation of thermal wind balance in the initial state, it was possible to use more realistic environments than in previous idealised studies. As a consequence, this study provides further insight into SJ evolution and dynamics and explores SJ robustness to different environmental conditions, assessed via a wide range of sensitivity experiments. The control simulation contains a cyclone that fits the Shapiro–Keyser conceptual model and develops a SJ whose dynamics are associated with the evolution of mesoscale instabilities along the airstream, including symmetric instability (SI). The SJ undergoes a strong descent while leaving the cloud-head banded tip and markedly accelerating towards the frontal-fracture region, revealed as an area of buckling of the already-sloped moist isentropes. Dry instabilities, generated by vorticity tilting via slantwise frontal motions in the cloud head, exist in similar proportions to moist instabilities at the start of the SJ descent and are then released along the SJ. The observed evolution supports the role of SI in the airstream’s dynamics proposed in a conceptual model outlined in a previous study. Sensitivity experiments illustrate that the SJ is a robust feature of intense Shapiro–Keyser cyclones, highlighting a range of different environmental conditions in which SI contributes to the evolution of this airstream, conditional on the model having adequate resolution. The results reveal that several environmental factors can modulate the strength of the SJ. However, a positive relationship between the strength of the SJ, both in terms of peak speed and amount of descent, and the amount of instability occurring along it can still be identified. In summary, the idealised simulations presented in this study show the robustness of SJ occurrence in intense Shapiro–Keyser cyclones and support and clarify the role of dry instabilities in SJ dynamics.

scholarly journals Dynamic Capabilities and Digital Marketing in Small and Medium-Sized Enterprises (SMEs) in Indonesia: a Systematic Analysis of Literature and Conceptual Model

2019 ◽  
Vol 8 (3S2) ◽  
pp. 531-534
Keyword(s):  
Firm Performance ◽  
Conceptual Model ◽  
Dynamic Capabilities ◽  
Positive Relationship ◽  
Digital Marketing ◽  
Empirical Validation ◽  
Marketing Capabilities ◽  
Systematic Analysis ◽  
National Economic

Small and Medium sized enterprises (SMEs) have proven to be the backbone of Indonesia’s economy. It gives contribution to 99.9% of national economic, absor 97% employee and contributes 60.34% to Indonesia GDP. Indonesia is known to be one of the most social media users. There is lack of studies to understand the role of dynamic capabilities and digital marketing on influencing the performance of SME’s in Indonesia. This study aims to develop a conceptual model linking dynamic capabilities, digital marketing capabilities and SME performance. Systematic literature review (SLR) method is used in this study. After getting result of SLR, than the authors develope the concept. More than 2000 publication published from 2011 to 2018 were screened with dynamic capabilities, digital marketing and SMEs’ performance as keywords. Finally, 20 journals were included for this review. Based on the review there were three possible relationships in the conceptual model which are (1) there is a positive relationship between dynamic capabilities and firm performance; (2) there is a positive relationship between dynamic capabilities and digital marketing capabilities and (3) there is a positive relationship between digital marketing capabilities and firm performance. It concludes with the need for further study to find empirical validation of the three relationships. Contribution of this study is giving the conceptual framework that both dynamic capabilities and digital marketing capabilities might have important roles to SMEs’ performance in Indonesia.

scholarly journals Relevansi Delimitasi Perbatasan Maritim Dengan Faktor Lingkungan

2021 ◽  
Vol 1 (2) ◽  
pp. 76
Author(s):  
Evi Purwanti
Keyword(s):  
Environmental Factors ◽  
Positive Relationship ◽  
Environmental Law ◽  
Mineral Resources ◽  
Conceptual Approach ◽  
Environmental Considerations ◽  
The Relationship ◽  
Selection Of

Introductioan: This article discusses the relevance of maritime border delimitation with environmental factors that affect the determination of delimitation.Purposes of the Research: The purpose of this study is to analyze the urgency of the role of the environment in the maritime border delimitation process. Specifically focused on analyzing whether there is a positive relationship between environmental considerations and the development of the delimitation process and to determine the environmental factors that influence the delimitation.Methods of the Research: This research uses normative research with a conceptual approach. Researchers use relevant environmental law concepts in the maritime border delimitation process.Results of the Research: The results of the study show that there is a relevance of environmental factors in determining maritime border delimitation, among others from factors: conservation of wildlife reserves, the principle of natural prolongation, the principle of sustainable development, mineral resources, and fisheries. The relationship between environmental factors and the delimitation process occurs in two ways: First, environmental considerations show a direct influence in the selection of the delimitation method. Here environmental factors are an important motive in the delimitation process. Second, environmental factors affect the delimitation process indirectly where there are a number of delimitation agreements that do not include specific provisions regarding the environment, but the evidence shows that the parties are motivated by environmental factors in negotiating delimitation.

The role of propagule pressure and environmental factors on the establishment of a large invasive cyprinid: black carp in the Laurentian Great Lakes basin

2021 ◽  
pp. 1-15
Author(s):  
Eric R.B. Smyth ◽  
D. Andrew R. Drake
Keyword(s):  
Environmental Factors ◽  
Great Lakes ◽  
Environmental Conditions ◽  
Propagule Pressure ◽  
Adult Survival ◽  
Relative Role ◽  
Joint Models ◽  
Black Carp ◽  
Invasive Fishes

Understanding the factors underlying species establishment is critical for the management of invasive fishes, yet the roles of propagule pressure and environmental factors are infrequently quantified in joint models. We estimated the establishment likelihood of the invasive black carp (Mylopharyngodon piceus) by examining the relative influence of propagule pressure (introduction size and age structure) and environmental factors (temperature-driven young-of-year [YOY] overwinter survival, adult survival, age at maturity, and longevity). Simulations demonstrated that both propagule pressure and environmental factors can act as non-linear bottlenecks to establishment. When the model was applied to 12 Great Lakes tributaries and nearshore areas, black carp establishment was probable with sufficient propagules and under most environmental conditions (median p = 0.21–0.73, 0.70–1.00, and 0.46–0.97 for 100 pairs of age 4, age 9, and age 16 fish, respectively), except for YOY (p < 0.01). Our analysis is one of the few studies to examine the relative role of propagule pressure and environmental conditions on establishment, indicating that both factors can lead to establishment failure independently or concurrently within an ecosystem.

scholarly journals Impact of temperature and photoperiod on survival and biomarkers of senescence in common woodlouse

2018 ◽  
Author(s):  
Charlotte Depeux ◽  
Ascel Samba-Louaka ◽  
Christine Braquart-Varnier ◽  
Jérôme Moreau ◽  
Jean-François Lemaître ◽  
...  
Keyword(s):  
Experimental Design ◽  
Environmental Factors ◽  
Environmental Conditions ◽  
Opposite Effect ◽  
Experimental Approach ◽  
Galactosidase Activity ◽  
Age Related ◽  
Living Organisms ◽  
The Impact

AbstractMost living organisms display a decline in physiological performances when ageing, a process called senescence that is most often associated with increased mortality risk. Previous researches have shown that both the timing and the intensity of senescence vary a lot within and among species, but the role of environmental factors in this variation is still poorly understood. To fill this knowledge gap, we investigated the impact of environmental conditions on the strength of senescence using an experimental design applied to a population of common woodlouse Armadillidium vulgare intensively monitored in the lab. Cellular senescence biomarkers are available in woodlouse and are age-related. These biomarkers provide relevant biomarkers to test the impact of environmental conditions, through changes in temperature and photoperiod, on individuals of the same age maintained in different environmental conditions. We found different effects of the environmental changing: the increasing of day light modification leaded the same effect as age on our senescence biomarkers while temperature modifications leaded the opposite effect as age on the β-galactosidase activity and cell size. We also demonstrated the existence of sex-specific responses to changes in environmental conditions. By using an experimental approach and biomarkers of senescence in woodlouse, we show that environmental conditions and sex both shape the diversity observed in senescence patterns of woodlouse and underline the importance of identifying senescence biomarkers to understand how environmental conditions influence the evolution of senescence.

scholarly journals Zeaxanthin, a Molecule for Photoprotection in Many Different Environments

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5825
Author(s):  
Barbara Demmig-Adams ◽  
Jared J. Stewart ◽  
Marina López-Pozo ◽  
Stephanie K. Polutchko ◽  
William W. Adams
Keyword(s):  
Genetic Variation ◽  
Environmental Factors ◽  
Excitation Energy ◽  
Environmental Conditions ◽  
Xanthophyll Cycle ◽  
Field Studies ◽  
Photosynthetic Productivity ◽  
High Degree ◽  
Insight Into

Conversion of sunlight into photochemistry depends on photoprotective processes that allow safe use of sunlight over a broad range of environmental conditions. This review focuses on the ubiquity of photoprotection associated with a group of interconvertible leaf carotenoids, the xanthophyll cycle. We survey the striking plasticity of this process observed in nature with respect to (1) xanthophyll cycle pool size, (2) degree and speed of interconversion of its components, and (3) flexibility in the association between xanthophyll cycle conversion state and photoprotective dissipation of excess excitation energy. It is concluded that the components of this system can be independently tuned with a high degree of flexibility to produce a fit for different environments with various combinations of light, temperature, and other factors. In addition, the role of genetic variation is apparent from variation in the response of different species growing side-by-side in the same environment. These findings illustrate how field studies can generate insight into the adjustable levers that allow xanthophyll cycle-associated photoprotection to support plant photosynthetic productivity and survival in environments with unique combinations of environmental factors.

scholarly journals Assessment of Physical Functioning: A Conceptual Model Encompassing Environmental Factors and Individual Compensation Strategies

2009 ◽  
Vol 89 (7) ◽  
pp. 705-714 ◽  
Author(s):  
Kristin M. Tomey ◽  
MaryFran R. Sowers
Keyword(s):  
Environmental Factors ◽  
Conceptual Model ◽  
Physical Functioning ◽  
Behavioral Strategies ◽  
Environmental Barriers ◽  
Performance Capacity ◽  
Physical Functions ◽  
Climbing Stairs

Commonly studied physical functions include activities such as walking and climbing stairs. Despite the acknowledged role of environmental factors and behavioral strategies to compensate for reduced performance capacity or environmental barriers in characterizing physical functioning, most assessments do not take these factors into account. This article presents a new conceptual model for assessment of relevant physical functioning while accounting for habitual environmental factors and compensation strategies.

scholarly journals Mediating Effects of Digital Technology on Entrepreneurial Orientation and Firm Performance : Evidence from Small and Medium-sized Enterprises (SMEs) in Indonesia

2019 ◽  
Vol 8 (5C) ◽  
pp. 692-696
Keyword(s):  
Firm Performance ◽  
Conceptual Model ◽  
Digital Technology ◽  
Entrepreneurial Orientation ◽  
Positive Relationship ◽  
Mediating Effects ◽  
Internet Users ◽  
National Economic ◽  
Technology Capability

Small and Medium sized enterprises (SMEs) plays important role in Indonesia economic. It contributes to 99.9% of national economic, 97% to employment and 60.34% to Indonesia GDP. Moreover, Indonesia is known to be one of the most internet users. However, currently, there is lack of studies to understand the role of digital technology and entrepreneur orientation on influencing the performance of SME’s in Indonesia. This study aims to develop a conceptual model linking entrepreneurial orientation, digital technology capability and SME performance. This study is using Systematic literature review (SLR) method. The result of SLR was used as the based for the concept development. More than 1100 publication published from 2010 to 2019 were screened with entrepreneurial orientation, digital technology and SMEs’ performance as keywords. Finally, 34 journals were included for this review. Based on the review there were three possible relationships in the conceptual model which are (1) there is a positive relationship between entrepreneurial orientation and firm performance; (2) there is a positive relationship between entrepreneurial orientation and digital technology capability and (3) there is a positive relationship between digital technology capability and firm performance. It concludes with the need for further study to find empirical validation of the three relationships. Contribution of this study is giving the conceptual framework that both entrepreneurial orientation and digital technology capability might have important roles to SMEs’ performance in Indonesia

Questions on the role of biofilms for the adaptation of microorganisms to unfavorable environmental factors by the example of P. aeruginosa

2020 ◽  
Vol 99 (4) ◽  
pp. 379-383
Author(s):  
Vasily N. Afonyushkin ◽  
N. A. Donchenko ◽  
Ju. N. Kozlova ◽  
N. A. Davidova ◽  
V. Yu. Koptev ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Environmental Factors ◽  
Barrier Function ◽  
Infectious Agent ◽  
Antagonistic Activity ◽  
The Body ◽  
Main Function ◽  
Pathogenic Potential ◽  
The Face

Pseudomonas aeruginosa is a widely represented species of bacteria possessing of a pathogenic potential. This infectious agent is causing wound infections, fibrotic cystitis, fibrosing pneumonia, bacterial sepsis, etc. The microorganism is highly resistant to antiseptics, disinfectants, immune system responses of the body. The responses of a quorum sense of this kind of bacteria ensure the inclusion of many pathogenicity factors. The analysis of the scientific literature made it possible to formulate four questions concerning the role of biofilms for the adaptation of P. aeruginosa to adverse environmental factors: Is another person appears to be predominantly of a source an etiological agent or the source of P. aeruginosa infection in the environment? Does the formation of biofilms influence on the antibiotic resistance? How the antagonistic activity of microorganisms is realized in biofilm form? What is the main function of biofilms in the functioning of bacteria? A hypothesis has been put forward the effect of biofilms on the increase of antibiotic resistance of bacteria and, in particular, P. aeruginosa to be secondary in charcter. It is more likely a biofilmboth to fulfill the function of storing nutrients and provide topical competition in the face of food scarcity. In connection with the incompatibility of the molecular radii of most antibiotics and pores in biofilm, biofilm is doubtful to be capable of performing a barrier function for protecting against antibiotics. However, with respect to antibodies and immunocompetent cells, the barrier function is beyond doubt. The biofilm is more likely to fulfill the function of storing nutrients and providing topical competition in conditions of scarcity of food resources.

Role of environmental factors in the etiology of hepatocellular carcinoma

2010 ◽  
Vol 151 (28) ◽  
pp. 1132-1136 ◽  
Author(s):  
István Tornai
Keyword(s):  
Hepatocellular Carcinoma ◽  
Hepatitis B Virus ◽  
Environmental Factors ◽  
Hepatitis B ◽  
Hepatitis A ◽  
Virus Hepatitis ◽  
B Virus

A krónikus vírushepatitisek jelentik ma a legismertebb okokat a hepatocellularis carcinoma (HCC) kialakulásában. A krónikus B- és C-vírus-hepatitis a májrákok körülbelül 40-50%-át okozza. A nyugati típusú társadalmakban a HCC előfordulása folyamatosan növekvő tendenciát mutat. Az alkohol számít a környezeti tényezők közül a legfontosabbnak, bár az alkoholfogyasztás a legtöbb országban csökken. Ez aláhúzza az egyéb környezeti tényezők fontosságát is. Az elfogyasztott alkoholmennyiséggel egyenes arányban növekszik a cirrhosis és a következményes HCC gyakorisága nőkben és férfiakban egyaránt. A kémiai anyagok közül a legismertebb a Kínában és Afrikában elterjedt aflatoxin, amely a gabonaféléket szennyező mycotoxin. Hasonló területeken endémiás, mint a hepatitis B-vírus, együtt szinergista hatást fejtenek ki. A dohányzás is egyértelműen bizonyított hepatocarcinogen hatással rendelkezik. Ez is jelentősen fokozódik, ha alkoholfogyasztással vagy vírushepatitisszel társul. Társadalmilag talán a legfontosabb az elhízás, a következményes nem alkoholos zsírmáj, illetve steatohepatitis és a 2-es típusú cukorbetegség, amelyek prevalenciája egyre fokozódik. Feltehetően ezek állnak a növekvő HCC-gyakoriság hátterében. Az inzulinrezisztencia és az oxidatív stressz képezik a legfontosabb patogenetikai lépéseket a májsejtkárosodásban. További fontos rizikótényező az orális fogamzásgátlók elterjedt használata. Egyes foglalkozások esetén a tartós szervesoldószer-expozíció is növeli a HCC rizikóját. Védelmet jelenthetnek az antioxidánsok, a szelén, a gyógyszerek közül a statinok és a feketekávé-fogyasztás.

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