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2022 ◽  
Vol 805 ◽  
pp. 150262
Author(s):  
Arbindra Timilsina ◽  
Oene Oenema ◽  
Jiafa Luo ◽  
Yuying Wang ◽  
Wenxu Dong ◽  
...  

2022 ◽  
Vol 130 (1) ◽  
pp. 35-38
Author(s):  
Kengo OKA ◽  
Wataru NISHIKI ◽  
Miho TAKASU ◽  
Naoki NOMA ◽  
Mitsunobu IWASAKI

2021 ◽  
Author(s):  
Colette Kelly ◽  
Cara Manning ◽  
Claudia Frey ◽  
Noah Noah Gluschankoff ◽  
Karen Casciotti

Obtaining nitrous oxide isotopocule measurements with isotope ratio mass spectrometry (IRMS) requires measuring the m/z ratios of the nitrous oxide (N2O) molecule as well as those of the NO+ fragment ion. This measurement depends on correcting for a phenomenon referred to as “scrambling” in the ion source, whereby the NO+ fragment ion contains the outer N atom from the N2O molecule. While descriptions of the scrambling correction exist in the literature, there has yet to be published a unified software package and method for performing this correction. We developed a user-friendly Python package (pyisotopomer), with a MATLAB alternative, to determine two coefficients that describe scrambling in the ion source of a given IRMS, and then to use this calibration to obtain N2O isotopocule measurements. We assess the sensitivity of pyisotopomer to its input parameters and discuss the relevant assumptions. We show that the scrambling behavior of an IRMS can vary with time, necessitating regular calibrations. We show that to obtain a relative uncertainty in site preference of <1‰, the relative uncertainty in each scrambling coefficient should be <0.2%. Finally, we present an intercalibration between two IRMS laboratories, using pyisotopomer to calculate scrambling and obtain N2O isotopocule data. Given these considerations, we discuss how to use this software package to obtain high-quality N2O isotopocule data from IRMS systems, including the use of appropriate reference materials and frequency of calibration.


Small ◽  
2021 ◽  
pp. 2106785
Author(s):  
Taito Murakami ◽  
Toshiya Shibata ◽  
Yuta Yasui ◽  
Kotaro Fujii ◽  
James R. Hester ◽  
...  

2021 ◽  
Vol 15 (12) ◽  
pp. e0009988
Author(s):  
M. Florencia Gil ◽  
Marisol Fassolari ◽  
Marina E. Battaglia ◽  
Corina M. Berón

Culex quinquefasciatus is a cosmopolitan species widely distributed in the tropical and subtropical areas of the world. Due to its long history of close association with humans, the transmission of arboviruses and parasites have an important role in veterinary and public health. Adult females feed mainly on birds although they can also feed on humans and other mammals. On the other hand, larvae are able to feed on a great diversity of microorganisms, including microalgae, present in natural or artificial breeding sites with a high organic load. These two particularities, mentioned above, are some of the reasons why this mosquito is so successful in the environment. In this work, we report the identification of a microalga found during field sampling in artificial breeding sites, in a group of discarded tires with accumulated rainwater. Surprisingly, only one of them had a bright green culture without mosquito larvae while the other surrounding tires contained a large number of mosquito larvae. We isolated and identified this microorganism as Neochloris aquatica, and it was evaluated as a potential biological control agent against Cx. quinquefasciatus. The oviposition site preference in the presence of the alga by gravid females, and the effects on larval development were analyzed. Additionally, microalga effect on Cx. quinquefasciatus wild type, naturally infected with the endosymbiotic bacterium Wolbachia (w+) and Wolbachia free (w−) laboratory lines was explored. According to our results, even though it is chosen by gravid females to lay their eggs, the microalga had a negative effect on the development of larvae from both populations. Additionally, when the larvae were fed with a culture of alga supplemented with balanced fish food used as control diet, they were not able to reverse its effect, and were unable to complete development until adulthood. Here, N. aquatica is described as a biological agent, and as a potential source of bioactive compounds for the control of mosquito populations important in veterinary and human health.


2021 ◽  
Author(s):  
Chun-Mei Li ◽  
Shun-Jie Yang ◽  
Jin-Ping Zhou

Abstract The alloying and magnetic disordering effects on the site occupation, elastic property, and phase stability of Co2 YGa (Y=Cr, V, and Ni) shape memory alloys are systematically investigated by using the first-principles exact muffin-tin orbitals method. It is shown that with increasing the magnetic disordering degree (y), their tetragonal shear elastic constant C' ((C 11 - C 12)/2) of the L21 phase decreases whereas the elastic anisotropy (A) increases, and upon tetragonal distortions the cubic phase gets more and more unstable. Co2CrGa and Co2VGa alloys with y ≥ 0.2 thus can show the martensitic transformation (MT) from L21 to D022 as well as Co2NiGa. In off-stoichiometric alloys, the site preference is controlled by both the alloying and magnetic effects. At the FM state, the excess Ga atom always tends to take the Y sublattice, whereas the excess Co atom favors the Y site when Y=Cr, and the excess Y atom prefers the Co site when Y=Ni. The Ga-deficient Y=V alloys can occur the MT also at the FM state by means of Co or V doping, and the MT temperature (T M ) should increase with their addition. In the corresponding FM Y=Cr alloys, nevertheless, with Co or Cr substituting for Ga, the reentrant MT (RMT) from D022 to L21 is promoted and then T M for the RMT should decrease. The alloying effect on the MT of these alloys is finally well explained by means of the Jahn-Teller effect at the paramagnetic (PM) state. At the FM state, it may originate from the competition between the austenite and martensite about their strength of the covalent banding between Co and Ga as well as Y and Ga.


2021 ◽  
Vol 50 (10) ◽  
pp. 2885-2898
Author(s):  
Noorul Ezyan Nor Hashim ◽  
Mohammad Saiful Mansor ◽  
Nurul Ashikin Abdullah ◽  
Rosli Ramli

Communal roosting by urban birds, such as crows, mynas, and starlings, can be a public nuisance due to excessive noise and fouling of the surroundings with droppings. Food availability within proximity to the roosting area is one of the key factors influencing roosting site preference and fidelity. The diets of roosting mynas and crows have been well-studied, yet little is known about the diet of the Asian glossy starling (AGS), Aplonis panayensis. This study focused on assessing the diet of roosting AGS and food resource availability around the roosting area. The AGS diet was assessed through microscopic analysis of stomach contents and droppings. The diet mainly consisted of fruits (76%) with a minor component of animal materials, i.e. ants, snails, and beetle larvae. Intact seeds found in the samples were identified using DNA barcoding. Seven out of the nine plant species detected were new records for the AGS diet. The most common fruit found in the samples was Trema orientalis, which grows extensively along roadsides within foraging areas of AGS. The availability of fruits of different fast-growing pioneer species around the roosting site ensured a continuous supply of food to the birds. Animal materials, which were consumed by chance during foraging, supplemented the fruit in the bird’s diet. Hence, the birds’ preference for the roosting site may have been influenced by the availability of various food resources around it.


Crystals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1256
Author(s):  
Wanchai Deeloed ◽  
Yuranan Hanlumyuang ◽  
Wanwisa Limphirat ◽  
Songwut Suramitr ◽  
Kantapat Chansaenpak ◽  
...  

In-situ investigations of structural transitions during the thermal-oxidative event of mixed-metal spinel oxide precursors, the so-called nickel- (NCO) and zinc-containing (ZCO) cobaltite spinel precursors, were investigated to understand the formations of the derived NiCo2O4 and ZnCo2O4 spinel oxides, respectively. In-situ XRD investigation revealed that emerged temperatures for spinel oxide phase were between 325 and 400 °C, depending on the cationic substituent. It indicated that the emerged temperature correlated with the absolute octahedral site preference energy (OSPE) of those cations that participated in the development of the spinel framework. Moreover, the incorporated nickel and zinc in the precursors was beneficial for inhibiting the occurrence of the undesired CoO phase. Time-resolved X-ray absorption spectroscopic (TRXAS) data suggested the local structure rearrangement of nickel and zinc throughout the calcination process, which differed from the behavior of single-metal cobalt system. The essential information reported herein provides a benefit to control the cationic distribution within spinel materials, leading to the tunable physical and chemical properties.


Author(s):  
M. Gombotz ◽  
K. Hogrefe ◽  
R. Zettl ◽  
B. Gadermaier ◽  
H. Martin. R. Wilkening

Nuclear magnetic resonance offers a wide range of tools to analyse ionic jump processes in crystalline and amorphous solids. Both high-resolution and time-domain   1 , 2 H ,   6 , 7 Li ,   19 F ,   23 Na NMR helps throw light on the origins of rapid self-diffusion in materials being relevant for energy storage. It is well accepted that Li + ions are subjected to extremely slow exchange processes in compounds with strong site preferences. The loss of this site preference may lead to rapid cation diffusion, as is also well known for glassy materials. Further examples that benefit from this effect include, e.g. cation-mixed, high-entropy fluorides ( Ba, Ca) F 2 , Li-bearing garnets ( Li 7 La 3 Zr 2 O 12 ) and thiophosphates such as LiTi 2 ( PS 4 ) 3 . In non-equilibrium phases site disorder, polyhedra distortions, strain and the various types of defects will affect both the activation energy and the corresponding attempt frequencies. Whereas in ( Me, Ca ) F 2 ( Me = Ba ,   Pb ) cation mixing influences F anion dynamics, in Li 6 PS 5 X ( X = Br ,   Cl ,   I ) the potential landscape can be manipulated by anion site disorder. On the other hand, in the mixed conductor Li 4 + x Ti 5 O 12 cation-cation repulsions immediately lead to a boost in Li + diffusivity at the early stages of chemical lithiation. Finally, rapid diffusion is also expected for materials that are able to guide the ions along (macroscopic) pathways with confined (or low-dimensional) dimensions, as is the case in layer-structured RbSn 2 F 5 or MeSnF 4 . Diffusion on fractal systems complements this type of diffusion. This article is part of the Theo Murphy meeting issue ‘Understanding fast-ion conduction in solid electrolytes’.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12256
Author(s):  
Sadrack Jabaraj Dhanaraj Frank ◽  
Govindan Veeraswami Gopi ◽  
Bivash Pandav

Anthropogenic disturbance and climate change have significantly affected the distribution of wetlands globally and particularly in Asian countries. Various types of wetlands are harboured across all the biogeographic zones in India. These wetlands provide vital ecological services and are rich in biodiversity. However, anthropogenic pressures continue to be a threat to these wetlands by affecting the flora and fauna that depend on them. Tree-nesting colonial waterbirds are vulnerable to these pressures as their colonies are typically located in wetlands and associated areas. Disturbances to these areas have resulted in the loss or shifting of many heronries. The present study was conducted in the Indian state of Tamil Nadu during the period of 2017–2019 to document the existing and previously unknown heronries of the landscape. A total of 101 heronries were documented in 22 districts. The Little Cormorant was the most dominant species, occurring in 79% of the sites, with relative abundances of 24% and 26% during 2017–2018 and 2018–2019, respectively. A total of 23 tree species were utilized by the birds for nesting and Vachellia nilotica trees were used for nesting in about 25% of the heronries. 19% of the heronries were situated inside protected areas and 81% were located outside protected areas. Out of the 58 active nesting sites reported in 2005, 43 have been lost or are no longer active. Species distribution modelling with presence only data indicated that the sites with a high probability of occurrence were confined to the major waterbodies and rivers. Spatial correlation showed that the heronries were dispersed randomly across the landscape. The population dynamics within heronries and colonial nesting waterbirds’ response to various environmental factors must be monitored continuously to conserve these heronries.


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