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2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Marta Magnani ◽  
Ilaria Baneschi ◽  
Mariasilvia Giamberini ◽  
Brunella Raco ◽  
Antonello Provenzale

AbstractHigh-Arctic ecosystems are strongly affected by climate change, and it is still unclear whether they will become a carbon source or sink in the next few decades. In turn, such knowledge gaps on the drivers and the processes controlling CO2 fluxes and storage make future projections of the Arctic carbon budget a challenging goal. During summer 2019, we extensively measured CO2 fluxes at the soil–vegetation–atmosphere interface, together with basic meteoclimatic variables and ecological characteristics in the Bayelva river basin near Ny Ålesund, Spitzbergen, Svalbard (NO). By means of multi-regression models, we identified the main small-scale drivers of CO2 emission (Ecosystem Respiration, ER), and uptake (Gross Primary Production, GPP) in this tundra biome, showing that (i) at point scale, the temporal variability of fluxes is controlled by the classical drivers, i.e. air temperature and solar irradiance respectively for ER and GPP, (ii) at site scale, the heterogeneity of fractional vegetation cover, soil moisture and vegetation type acted as additional source of variability for both CO2 emissions and uptake. The assessment of the relative importance of such drivers in the multi-regression model contributes to a better understanding of the terrestrial carbon dioxide exchanges and of Critical Zone processes in the Arctic tundra.


Nanomaterials ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 16
Author(s):  
Irina A. Shurygina ◽  
Galina F. Prozorova ◽  
Irina S. Trukhan ◽  
Svetlana A. Korzhova ◽  
Nataliya N. Dremina ◽  
...  

A new original copper nanocomposite based on poly-N-vinylimidazole was synthesized and characterized by a complex of modern physicochemical and biological methods. The low cytotoxicity of the copper nanocomposite in relation to the cultured hepatocyte cells was found. The possibility to involve the copper from the nanocomposite in the functioning of the copper-dependent enzyme systems was evaluated during the incubation of the hepatocyte culture with this nanocomposite introduced to the nutrient medium. The synthesized new water-soluble copper-containing nanocomposite is promising for biotechnological and biomedical research as a new non-toxic hydrophilic preparation that is allowed to regulate the work of key enzymes involved in energy metabolism and antioxidant protection as well as potentially serving as an additional source of copper.


2021 ◽  
Vol 23 (2) ◽  
pp. 248
Author(s):  
La Ode Topo Jers ◽  
Erens Elvianus Koodoh ◽  
Hasniah Hasniah ◽  
Abdul Jalil ◽  
La Ode Muhammad Ruspan Takasi ◽  
...  

Food is a critical aspect of community resilience. The Covid-19 pandemic, however, has affected the natural environment, making food supply scarce and ultimately impacting economic and national stability. Despite this, the Mowewe community shares a local culture by which its people get empowered to maintain food security. Therefore, this study aims to discover and describe the local community's culture in Mowewe District in establishing a food security system. The method used was ethnography with a qualitative approach. Data were collected through participant observation, in-depth interviews, and documentation, after which the data were analyzed using qualitative descriptive techniques. The findings revealed that the local culture of the Mowewe community was built upon the concept of Mekambare, principles of gotong royong (cooperation), and ecological adaptation. The Mowewe community was of deep concern for the pattern of life balance during the pandemic. They took advantage of natural resources by clearing agricultural land to grow rice, corn, patchouli, and sago and keeping bees in the forest to produce honey for an additional source of income and immunity


2021 ◽  
Vol 83 (6) ◽  
pp. 32-40
Author(s):  
K.V. Avdiyuk ◽  
◽  
A.O. Roy ◽  

Every year the volume of production of poultry products all over the world is growing steadily. This contributes to a constant increase in the amount of by-products of poultry processing in the form of down and feather waste, which are dangerous for the environment due to the hard-to-degrade keratin protein and a large number of microbial pathogens. Therefore, the use of environmentally friendly methods for the destruction of keratin substrates due to keratinases of microorganisms is an urgent area of research. The aim of this work was to select the optimal cultivation conditions for the Bacillus megaterium strain UCM B-5710 to increase the activity of the keratinase synthesized by it. Methods. The culture was grown at 28°C, 201 rpm for 7 days on a basic nutrient medium containing defatted chicken feathers as the only source of carbon and nitrogen. The selection of optimal cultivation conditions was carried out according to the following parameters: temperature (21°C, 28°C, 42°C), stirring speed (201 rpm, 212 rpm), amount of inoculum (5%, 10%, 15% , 20%, 25%), the initial pH value of the nutrient medium (4.0–11.0), concentration of keratin-containing substrate (0.1%, 0.2%, 0.5%, 1.0%, 1.5%, 2.0%), additional carbon source (glucose, galactose, lactose, maltose, sucrose, mannitol, potato and corn starch, soluble starch, soybean meal) and nitrogen (NH4Cl, NH4NO3, (NH4)2SO4, NaNO3, urea, peptone, tryptone, yeast extract and soybean meal) at a concentration of 1%. Keratinase activity was assessed by the UV absorption at 280 nm of the hydrolysis products of keratin-containing raw materials. Protein was determined by the Lowry method. Results. The dynamics of the enzyme synthesis showed that the culture of B. megaterium UCM B-5710 exhibited the highest keratinase activity on the 3rd day, and complete splitting of feathers was observed on the 4–5th days. The selection of the concentration of the keratin-containing substrate showed that 0.5% is the optimal concentration. The study of the influence of the initial pH value of the nutrient medium indicates that the culture grew well at pH 6.0–7.0 and pH 9.0–11.0, but at pH 8.0 its growth was very weak. The culture exhibited the maximum keratinase activity at pH 10.0. In addition, at this pH value, complete splitting of feathers was visually observed. The influence of such a key factor as temperature on the growth and synthesis of the enzyme by B. megaterium UCM B-5710 culture demonstrated complete splitting of feathers already on the 2nd day of cultivation at 42°C, at 21°C the culture split feathers very poorly. The introduction of the inoculum into the composition of the nutrient medium in an amount of 15% of the volume of the medium and the mixing intensity of 212 rpm turned out to be optimal. Besides, it was shown that the introduction of an additional source of carbon or nitrogen had an ambiguous effect on the level of keratinase activity of B. megaterium UCM B-5710. Complete inhibition of enzyme synthesis was observed when ammonium sulfate was added to the nutrient medium, and partial inhibition was observed in the case of glucose, lactose, and maltose. Potato, corn, and soluble starch stimulated keratinase synthesis. The majority of inorganic nitrogen sources (ammonium chloride and nitrate) did not affect the synthesis of B. megaterium UCM B-5710 keratinase, while organic sources (urea, peptone, tryptone, yeast extract) increased the level of keratinase activity by 20–50%. However, the most effective result was obtained using soybean meal, the addition of which to the nutrient medium increased the keratinase activity by 2.5 times. Conclusions. As a result of the studies, the optimal conditions for cultivation of the B. megaterium UCM B-5710 strain were selected: the optimum temperature for the growth and development of the culture is 42°C, the initial pH value is 10.0, the stirring speed is 212 rpm and the amount of inoculum introduced is 15%, an additional source of carbon and nitrogen in the form of soybean meal at a concentration of 0.5%. This made it possible to increase the activity of keratinase by 4 times.


2021 ◽  
Vol 11 (3) ◽  
pp. 138-144
Author(s):  
Tatiana A. MEDVEDEVA

The preservation of the historical, urban planning and architectural heritage of historical cities requires a special approach to the environment modernization. The modern period is characterized by the search for new safe waste management algorithms. It often leads to the construction of large-scale discordant objects. This process puts forward new requirements for the preservation of the visual protection zones of cultural heritage objects. The article is devoted to a promising strategy for optimizing of devastated territories. It includes the creation of overpass pedestrian links, which can be an additional source of landscaping, as well as open up new opportunities for the transit of engineering networks. The article analyzes the possibility of using such architectural and spatial solutions to modernize the waste management infrastructure of urban devastated.


2021 ◽  
Vol 5 ◽  
Author(s):  
Judith Jurjens

This paper is a publication of P. Turin CGT 54019, which contains an excerpt from The Teaching of Khety, also known as The Satire of the Trades. The papyrus provides a welcome additional source for the second part of the composition (chapters 21–30), particularly because it offers some interesting variants that are unparalleled in the other sources. After a brief introduction on variants in general, including scribal errors, these variants are discussed in detail. The colophon that concludes the papyrus is badly preserved. However, it mentions the mortuary temple of Ramesses III at Medinet Habu. This is quite remarkable, since locations are seldom referred to in the colophons of literary texts. These rare instances are analyzed here to try to reconstruct the manuscript’s colophon. Finally, the relationship between literary texts and mortuary temples is discussed to shed light on the social context of P. Turin CGT 54019. ملخص هذا النص هو إحدى منشورات P. Turin CGT 54019، والذي يحتوي على مقتطف من "وصايا خيتي" ، المعروف أيضاً باسم "مساوئ الحِرَف". تمثل البردية مصدراً إضافياً لمقدمة الجزء الثاني من العمل (الفصول 21-30)، وبالتحديد لأنها تقدم بعض المتغيرات المثيرة للاهتمام التي لا مثيل لها في المصادر الأخرى. بعد مقدمة موجزة عن المتغيرات بشكل عام، بما في ذلك أخطاء الكاتب، تمّت مناقشة هذه المتغيرات بالتفصيل. بيانات المنشور التي تختم بها البردية محفوظة بشكل سيئ. ومع ذلك فإنها تتحدث عن المعبد الجنائزي لرمسيس الثالث في مدينة هابو. هذا أمر جدير بالذكر، حيث نادراً ما يشار إلى موقع محدد في بيانات المنشور للنصوص الأدبية. يتم هنا دراسة وتحليل هذه الحالات النادرة لمحاولة إعادة بناء بيانات المنشور الخاصة بالمخطوطة. أخيراً، تمت مناقشة العلاقة بين النصوص الأدبية والمعابد الجنائزية لإلقاء الضوء على المنظومة الاجتماعية لـ P. Turin CGT 54019 .


Sensors ◽  
2021 ◽  
Vol 21 (24) ◽  
pp. 8242
Author(s):  
Raoul R. Nigmatullin ◽  
Vadim S. Alexandrov

In the first time we apply the statistics of the complex moments for selection of an optimal pressure sensor (from the available set of sensors) based on their statistical/correlation characteristics. The complex moments contain additional source of information and, therefore, they can realize the comparison of random sequences registered for almost identical devices or gadgets. The proposed general algorithm allows to calculate 12 key correlation parameters in the significance space. These correlation parameters allow to realize the desired comparison. New algorithm is rather general and can be applied for a set of other data if they are presented in the form of rectangle matrices. Each matrix contains N data points and M columns that are connected with repetitious cycle of measurements. In addition, we want to underline that the value of correlations evaluated with the help of Pearson correlation coefficient (PCC) has a relative character. One can introduce also external correlations based on the statistics of the fractional/complex moments that form a complete picture of correlations. To the PCC value of internal correlations one can add at least 7 additional external correlators evaluated in the space of fractional and complex moments in order to realize the justified choice. We do suppose that the proposed algorithm (containing an additional source of information in the complex space) can find a wide application in treatment of different data, where it is necessary to select the “best sensors/chips” based on their measured data, presented usually in the form of random rectangle matrices.


2021 ◽  
Vol 2086 (1) ◽  
pp. 012212
Author(s):  
M D Soldatenkova ◽  
A D Triznova ◽  
E M Baeva ◽  
P I Zolotov ◽  
A I Lomakin ◽  
...  

Abstract High-quality thin NbN films are very crucial for realizing quantum devices. Here, we investigated electrical transport and noise properties of a series of thin NbN films of various thicknesses grown on r-cut sapphire substrate using a DC magnetron sputtering technique. The films exhibit non-uniform thickness dependences for superconducting transition temperature (Te ) and normal-state resistivity. Morphological characterization of NbN samples of various thicknesses reveals uniform structure in thin films and granular structure in thick films. By measuring transport and noise properties in a normal state, we observe that the granular structure of NbN films does not have a strong effect on resistivity and does not cause an additional source of current noise.


2021 ◽  
Vol 8 (S2) ◽  
Author(s):  
Jordan M. Vandjelovic ◽  
Darcy Merchant

Abstract Background Motor vehicle crashes (MVC’s) in the American Indian/Alaska Native (AI/AN) communities account for 43% of unintentional injury deaths. This article introduces MVC data and geographic information system (GIS) mapping for tribal reservations. Methods Utilizing a sample of Montana Department of Transportation (DOT) data for the Flathead reservations to calculate frequencies and proportions of crash types (i.e., property damage or no-injury, injury, fatality or unknown), while also mapping these data to provide a cross-sectional snapshot of MVC’s. Results Overall, 515 MVC’s occurred for years 2016 through 2018, with no-injury, injury, and fatality accounting for 72.2%, 24.9% and 1.8% of all crashes, respectively, with the number of MVC’s ranging up to 30 per square mile. Conclusion Examining DOT data and utilizing it for visual representation of MVC’s can be used as an additional source in uncovering patterns and trends on Tribal reservations and supporting MVC prevention efforts.


2021 ◽  
Vol 94 (1) ◽  
Author(s):  
Carezza Botto-Mahan ◽  
Rodrigo Medel

AbstractThe source of Darwin’s illness has been a contentious issue in the literature for almost 70 years. Different causal factors have been invoked to account for his symptoms, including Chagas disease. The Chagas hypothesis is based upon Darwin’s diary, in which he narrates his experience with kissing bugs, the main vector of the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. In this contribution, we examine the consistency of the “Chagas disease hypothesis” in the light of current ecological and epidemiological knowledge of the disease in Chile. According to his diary and letters, during his overland trips, Darwin slept in rural houses and outdoors for 128 days in a “hyperendemic” area for Chagas disease, more than exposing him to kissing bugs. This observation conveys a likely additional source of infection than previously considered, which might reinforce the idea that Chagas disease contributed to Darwin’s manifest physical deterioration.


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