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1.
Zookeys ; 1211: 101-130, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39262607

RESUMEN

A new karst-dwelling bent-toed gecko of the Cyrtodactylusintermedius group is described from Khlong Hat District, Sa Kaeo Province, eastern Thailand, based on an integrative taxonomic analysis of genetic data and morphological characteristics. Phylogenetic analyses using the mitochondrial NADH dehydrogenase subunit 2 (ND2) gene revealed that topotypes of C.intermedius were sister to a clade containing C.kulenensis from Cambodia, an unnamed lineage from Sakaerat Biosphere Reserve in Nakhon Ratchasima Province, Thailand, and the Khlong Hat lineage described here as Cyrtodactyluskhlonghatensis sp. nov. Multivariate analyses of morphometric and meristic characters showed that C.khlonghatensis sp. nov. is morphologically distinct from all other species in the group by having the combination of SVL 76.5-82.8 mm in adult males and 88.5 mm in an adult female; eight supralabial and nine infralabial scales; 30-32 paravertebral tubercles; 20 or 21 longitudinal rows of dorsal tubercles; 43 or 44 ventral scales; seven or eight expanded subdigital lamellae on the 4th toe; 12 unmodified subdigital lamellae on the 4th toe; 19 or 20 total subdigital lamellae on the 4th toe; 31 or 32 total number of enlarged femoral scales; enlarged femoral and precloacal scales continuous; 6-8 pore-bearing precloacal scales in males; three or four rows of enlarged post-precloacal scales; 1-3 postcloacal tubercles; proximal femoral scales less than one-half the size of distal femoral scales; absence of interdigital pocketing between digits of forefeet and hindfeet; and posterior border of the nuchal loop rounded. Uncorrected pairwise genetic divergences (p-distances) between the new species and other species of the intermedius group ranged from 4.73-22.55%. The discovery of this new species exclusively in isolated karst formations from the Thai-Cambodia border suggests that there may be further undiscovered Cyrtodactylus in unexplored karst landscapes along the border of eastern Thailand and western Cambodia.

2.
Gels ; 10(7)2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39057491

RESUMEN

In this research, the influence of the thermal treatment of geopolymer gels at 300 °C, 600 °C and 900 °C when incorporated with 5% rare earth elements (REEs) in the form of (GP-Sm) Sm2O3 and (GP-Nd) Nd2O3 was investigated. Changes in the chemical and structural properties of the geopolymer gels during thermal treatment for 1 h were monitored. Physico-chemical characterization was performed using the following methods: diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), scanning electron microscopy with energy dispersive spectrometry (SEM-EDS), and X-ray photoelectron spectroscopy (XPS). Besides the characterization of the fundamental properties, some practical macroscopic properties were analyzed as well: sorptivity, open porosity, and Archimedean density. The stretching vibrations of Nd-O-Si and Sm-O-Si were confirmed at a value of around 680 cm-1and an Nd-O-Si absorption band at a higher value, together with the most dominant band of Si-O stretching vibration similar for all the samples. No significant chemical changes occurred. Structural analysis showed that for GP-Nd, the largest pore diameter was obtained at 900 °C, while for GP-Sm, the largest pore diameter was obtained at 600 °C. EDS confirmed the amount of dopant to be about 5%. X-ray photoelectron spectroscopy showed that for GP-Nd, the ratio of Si and Al changed the most, while for GP-Sm, the ratio of Si and Al decreased with increasing temperature. The contributions of both dopants in the GP-gel structure remained almost unchanged and stable at high temperatures. The atomic percentages obtained by XPS analysis were in accordance with the expected trend; the amount of Si increased with the temperature, while the amount of Al decreased with increasing temperature. The sorptivity and open porosity showed the highest values at 600 °C, while the density of both geopolymers decreased linearly with increasing temperature.

3.
Materials (Basel) ; 17(13)2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38998192

RESUMEN

The more effective use of readily available Ce in FeNdB sintered magnets is an important step towards more resource-efficient, sustainable, and cost-effective permanent magnets. These magnets have the potential to bridge the gap between high-performance FeNdB and hard ferrite magnets. However, for higher degrees of cerium substitution (>25%), the magnetic properties deteriorate due to the lower intrinsic magnetic properties of Fe14Ce2B and the formation of the Laves phase Fe2Ce in the grain boundaries. In this paper, sintered magnets with the composition Fe70.9-(CexNd1-x)18.8-B5.8-M4.5 (M = Co, Ti, Al, Ga, and Cu; with Ti, Al, Ga, and Cu less than 2.0 at% in total and Cobal; x = 0.5 and 0.75) were fabricated and analyzed. It was possible to obtain coercive fields for higher degrees of Ce substitution, which previous commercially available magnets have only shown for significantly lower degrees of Ce substitution. For x = 0.5, coercivity, remanence, and maximum energy product of µ0Hc = 1.29 T (Hc = 1026 kA/m), Jr = 1.02 T, and (BH)max = 176.5 kJ/m3 were achieved at room temperature for x = 0.75 µ0Hc = 0.72 T (Hc = 573 kA/m), Jr = 0.80 T, and (BH)max = 114.5 kJ/m3, respectively.

4.
Environ Pollut ; 358: 124527, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38992831

RESUMEN

Neodymium oxide (Nd2O3) is a rare earth element that can lead to various type of tissue and organ damage with prolonged exposure. The long noncoding RNA small nucleolar ribonucleic acid host gene 5 (lncRNA SNHG5) plays a role in disease progressiong. However, its connection with Nd2O3 induced reproductive harm in males has not been thoroughly investigated. Our research discovered that exposure to Nd2O3 increases the expression of SNHG5 in the testes of mice, which in turn binds directly to and reduces in the protein levels of insulin like growth factor 2 mRNA-binding protein 1 (IGF2BP1) both in vivo and in vitro. This process disrupts the cytoskeleton of blood-testis barrier(BTB) by impacting the stability of the tight junction protein Occludin (Ocln) mRNA structure and the permeability of the BTB. In summary, our study elucidates the regulatory mechanism of SNHG5/IGF2BP1/Occludin axis in Nd2O3-induced BTB injury, providing valuable insights for the treatment of male infertility.


Asunto(s)
Barrera Hematotesticular , Ocludina , ARN Largo no Codificante , Animales , Masculino , Ratones , Barrera Hematotesticular/metabolismo , Ocludina/genética , Ocludina/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Testículo/metabolismo
5.
Photochem Photobiol Sci ; 23(8): 1533-1542, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39030314

RESUMEN

Removal of organic dyes like methylene blue (MB) from industrial effluents serves as potential source of potable water. Photocatalytic degradation using sustainable catalyst is deemed to be an affordable solution. In this work, Nd2O3/MgO nanocomposite with different compositions (1, 3, and 5wt% Nd2O3 with MgO) have been achieved using hydrothermal synthesis and characterized extensively. Interestingly, increasing Nd2O3 proportion (1-5%) enhances light absorption, and decreases band gap and electron-hole recombination. The efficacy of the photocatalysts is tested with the degradation of MB dye, through optimizing Nd2O3/MgO proportion, contact time, catalyst dose, and pH. Interestingly, control experiments reveal that 5wt% Nd2O3/MgO achieve 99.6% degradation of MB in 90 min at pH 7, compared to 88.8% with bare MgO under same condition. Kinetic data show that 5wt% Nd2O3/MgO exhibits ca. 3 times higher degradation rate compared to MgO. For the first time, our work enable MgO-based sustainable photocatalyst development with minimum (5 wt%) rare-earth combination to achieve excellent photocatalytic degradation performance.

6.
Heliyon ; 10(9): e29894, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38707437

RESUMEN

To improve the photocatalytic property of TiO2 thin films, the composite thin films of TiO2/Nd2O3 structure were fabricated by electron-beam physical vapor deposition method, and the photocatalytic property of the fabricated films was experimentally studied in the present work. The XRD and Raman analyses show that the TiO2/Nd2O3 films are mainly hexagonal crystalline phase of Nd2O3. The XPS analysis for the chemical state changes of Ti, O and Nd of the basic elements in the films is confirming the electron flow in the internal electric field which generated in the TiO2/Nd2O3 films. The surface morphology shows the lattice distortion which affects the changes in the energy band structure. Moreover, the formation of n-n homojunctions improved the separation efficiency of electrons and holes, and enhanced the catalytic activity. The photocatalytic performance for the methylene blue target dye shows that the sample with TiO2 thickness of 20-25 nm has better performance, high degradation efficiency and high reaction rate.

7.
J Synchrotron Radiat ; 31(Pt 4): 877-887, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38771778

RESUMEN

Nanoscale structural and electronic heterogeneities are prevalent in condensed matter physics. Investigating these heterogeneities in 3D has become an important task for understanding material properties. To provide a tool to unravel the connection between nanoscale heterogeneity and macroscopic emergent properties in magnetic materials, scanning transmission X-ray microscopy (STXM) is combined with X-ray magnetic circular dichroism. A vector tomography algorithm has been developed to reconstruct the full 3D magnetic vector field without any prior noise assumptions or knowledge about the sample. Two tomographic scans around the vertical axis are acquired on single-crystalline Nd2Fe14B pillars tilted at two different angles, with 2D STXM projections recorded using a focused 120 nm X-ray beam with left and right circular polarization. Image alignment and iterative registration have been implemented based on the 2D STXM projections for the two tilts. Dichroic projections obtained from difference images are used for the tomographic reconstruction to obtain the 3D magnetization distribution at the nanoscale.

8.
Zoolog Sci ; 41(3): 257-262, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38809864

RESUMEN

The grey-headed lapwing (Vanellus cinereus) is a wading species in East Asia. However, examples of regional population dynamics and genetic research are limited. To reconsider the natural history and current status of the grey-headed lapwing in Japan, we analyzed the genetic diversity of the Japanese grey-headed lapwing population. We collected 77 grey-headed lapwing samples from 12 locations across Japan during the breeding season and three individuals during the wintering season and extracted DNA; 496-bp sequences of the ND2, which form part of the mitochondrial DNA, were determined for genetic analysis of the population. Consequently, 10 haplotypes were detected in 80 individuals, and 67 individuals, 84% of the total, shared two haplotypes, namely Vc1 and Vc2. Furthermore, the results showed that the prevalence of Vc1 was higher mainly in northern Japan, while that of Vc2 was higher mainly in southern Japan. Genetic diversity analysis showed that the overall haplotype diversity in Japan was 0.617, which is not particularly low. The sequence of Vc1 was exactly the same as that of grey-headed lapwing in China. Our study revealed the genetic structure of the grey-headed lapwing, suggesting that as the grey-headed lapwing expanded its distribution area into southern Japan, many Vc2-positive individuals migrated southward, resulting in a higher detection rate of Vc2 in southern Japan.


Asunto(s)
Charadriiformes , ADN Mitocondrial , Variación Genética , Animales , ADN Mitocondrial/genética , Haplotipos , Japón , Charadriiformes/genética
9.
Animals (Basel) ; 14(6)2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38539955

RESUMEN

A large variety of microorganisms ingested with food constitute animals' intestinal microflora, enhancing and maintaining the homeostasis of the host. Rations enriched with probiotics are a method recommended to prevent undesirable conditions. To date, research has been limited to farmed animals and reared fish, creating a knowledge gap concerning the effect of probiotics on the growth rate, physiological responses, and energy metabolism of invertebrates such as the land snail Cornu aspersum. Herein, juvenile snails (26.23 ± 0.5 mm shell diameter and 8.23 ± 1.02 g body weight) were fed L. plantarum probiotic-enriched rations in two different proportions (1.25 mg and 2.5 mg), and their growth rate was monitored for three months. Additionally, the RNA/DNA and Bax/Bcl-2 ratios, HSP gene expression and protein levels, and ND2 expression, were measured in the hepatopancreas, digestive tract, and mantle. Although the snails' growth rate was not affected, the RNA/DNA ratio presented an increase in various tissues, indicating an intense physiological response. Also, probiotic administration demonstrated low levels of the Bax/Bcl-2 ratio. HSP levels were higher in the presence of probiotics, probably signaling an attempt by the animal to face potentially stressful situations. Finally, ND2 expression levels in the hepatopancreas indicate intense metabolic and antioxidant activity.

10.
Zookeys ; 1192: 83-102, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38419746

RESUMEN

We describe a new species of the genus Cyrtodactylus based on five adult specimens from Bac Ha District, Lao Cai Province, northern Vietnam. Cyrtodactyluslucisp. nov. is distinguished from the remaining Indochinese bent-toed geckos by a combination of the following morphological characteristics: medium size (SVL up to 89.5 mm); dorsal tubercles in 17-19 irregular transverse rows; ventral scales in 32-34 longitudinal rows at midbody; precloacal pores present in both sexes, 9 or 10 in males, 8 or 9 in females; 12-15 enlarged femoral scales on each thigh; femoral pores 9-12 in males, 5-10 in females; postcloacal tubercles 2-4; lamellae under toe IV 21-23; dorsal pattern consisting of 5 or 6 irregular dark bands, a thin neckband without V-shape or triangle shape in the middle, top of head with dark brown blotches; subcaudal scales transversely enlarged. Molecular phylogenetic analyses recovered the new species as the sister taxon to C.gulinqingensis from Yunnan Province, China, with strong support from all analyses and the two taxa are separated by approximately 8.87-9.22% genetic divergence based on a fragment of the mitochondrial ND2 gene. This is the first representative of Cyrtodactylus known from Lao Cai Province.

11.
Molecules ; 28(23)2023 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-38067647

RESUMEN

The synthesis of Nd-Fe-B magnetic powders via chemical techniques presents significant promise, but poses challenges due to their inherent chemical instability. In this investigation, Nd-Fe-B hard magnetic particles were synthesized utilizing an eco-friendly and simple microwave-assisted hydrothermal synthetic method. The technique involves the synthesis of the Nd-Fe-B oxide precursor using the microwave-assisted hydrothermal method, followed by reduction-diffusion using CaH2. The microwave-assisted hydrothermal technique presents a viable approach for preparing Nd-Fe-B precursor particles, offering advantages such as time and energy efficiency and environmental sustainability. The synthesized Nd-Fe-B particles demonstrated a coercivity of up to 2.3 kOe. These magnetic particles hold significant potential for use in high-performance permanent magnets, and can effectively contribute to developing high-energy density exchange-coupled nanocomposite magnets. This study also offers valuable insights into the design and synthesis of additional magnetic materials based on rare earth elements.

12.
Polymers (Basel) ; 15(20)2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37896328

RESUMEN

Polyvinyl alcohol (PVA) and Neodymium (III) oxide (Nd2O3) were combined to synthesized flexible innovative PVA/Nd2O3 polymer composite samples utilizing a solution casting approach for use in dielectric devices. The XRD, FTIR, and SEM methods are all investigated to characterize the composite films. In a frequency of 50 Hz to 5 MHz, the effects of additive Nd2O3 on the dielectric behavior of PVA were recorded. The PVA/Nd2O3 composite films were successfully fabricated, as shown by XRD and infrared spectroscopy. The scanning microscopy pictures showed that the Nd2O3 was loaded and distributed uniformly throughout the PVA. After the incorporation of Nd2O3, the composite PVA/Nd2O3 has a conductivity of 6.82 × 10-9 S·cm-1, while the PVA has a conductivity of 0.82 × 10-9 S·cm-1. Another improvement is the decrease in the relaxation time from 14.2 × 10-5 s for PVA to 6.35 × 10-5 s for PVA/Nd2O3, and an increase in the dielectric constant of 0.237 for PVA to 0.484 at a frequency of 100 Hz. The results showed that the composite samples have considerable changes as flexible films in different applications, including batteries and electronic circuits.

13.
Toxicol Sci ; 197(1): 27-37, 2023 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-37831906

RESUMEN

Some rare earth elements are occupational and environmental toxicants and can cause organ and systemic damage; therefore, they have attracted global attention. Neodymium oxide (Nd2O3) is a rare earth element that is refined and significantly utilized in China. The long noncoding RNA (lncRNA) H19 is encoded by the H19/IGF2 imprinted gene cluster located on human chromosome 11p15.5. H19 has become a research focus due to its ectopic expression leading to the promotion of fibrosis. However, the mechanisms by which it causes pulmonary fibrosis are elusive. This investigation indicates that biologically active Nd2O3 increases H19, SNIP1, and c-myc, decreases miR-29a-3p, accelerates macrophage M2 polarization, and causes pulmonary fibrosis in mice lung tissues. In macrophage-differentiated THP-1 cells, Nd2O3 (25 µg/ml) enhanced H19, SNIP1, and c-myc, reduced miR-29a-3p, accelerated macrophages M2 polarization, and stimulated fibrogenic cytokine (TGF-ß1) secretion. Furthermore, the coculturing of Nd2O3-treated macrophage-differentiated THP-1 cells. And human embryonic lung fibroblast cells activated lung fibroblast, which increases the levels of collagen I, α-SMA, p-Smad2/3, and Smad4, whereas H19 knockdown or miR-29a-3p upregulation in macrophages had opposite effects. Moreover, it was revealed that H19/miR-29a-3p/SNIP1/c-myc regulatory axis is involved in pulmonary fibrosis induced by Nd2O3. Therefore, this study provides new molecular insights into the mechanism of pulmonary fibrosis by Nd2O3.


Asunto(s)
MicroARNs , Fibrosis Pulmonar , ARN Largo no Codificante , Humanos , Animales , Ratones , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/genética , Óxidos , Proteínas de Unión al ARN
14.
Materials (Basel) ; 16(15)2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37569964

RESUMEN

The magnetic properties of magnetic nanocomposites consisting of hard and soft magnetic phases are dependent not only on the intrinsic properties but also on the grain structure and volume ratio of the two phases. In this study, we performed a systematic micromagnetic simulation on the magnetic properties of Ce2Fe14B/α-Fe and Nd2Fe14B/α-Fe nanocomposites. The volume fractions of the hard magnetic Nd2Fe14B or Ce2Fe14B phase were varied from 80% to 40%, and the grain sizes of the hard magnetic phase and the soft magnetic α-Fe phase were changed independently from 10 nm to 40 nm. The results show that when the grain size of both hard and soft phases is 10 nm and the volume fraction of the hard phase is 70%, the highest maximum magnetic energy product can be obtained in both Ce2Fe14B/α-Fe and Nd2Fe14B/α-Fe nanocomposites. The hard magnetic properties of Ce2Fe14B/α-Fe nanocomposite decrease significantly when the volume fraction of the α-Fe phase exceeds 30%. However, for the Nd2Fe14B/α-Fe system, this situation only occurs when the α-Fe volume fraction exceeds 40%. The reason for this is not only because of the low anisotropic field and the smaller exchange coupling length between the soft and hard magnetic phases, but also because of the lower saturation magnetization of the hard phase. The grain size has greater effects on the magnetic properties compared to the volume fraction of the hard magnetic phase. The main reason is that as the grain size increases, the remanence of the nanocomposite decreases sharply, which also leads to a rapid decrease in the maximum magnetic energy product. The simulation results on the effects of phase ratio and grain size have been verified by experiments on melt-spun Ce2Fe14B/α-Fe alloys with various compositions prepared by melt-spinning followed by annealing for various lengths of time. Due to the influence of demagnetization energy, the hard magnetic phase with high saturation magnetization is preferred for the preparation of high-performance nanocomposite magnets.

15.
Food Chem (Oxf) ; 7: 100181, 2023 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-37637373

RESUMEN

Food authentication is a mandatory effort to assure the fair-trade. This study developed a duplex polymerase chain reaction (PCR) from the NADH dehydrogenase subunit 2 (ND2) gene to amplify specific segments of a cattle and porcine DNA. A universal forward primer composed of nineteen base pairs (bp) (3'-CCAAACACAACTCCGAAAA-5') and species-specific reverse primers composed of twenty (3'-CCAAACACAACTCCGAAAA-5') and twenty-one (3'-TGGCAAGAATTAGGACGGTTA-5') bp were used to limit the amplified DNA segment for porcine and cattle. The PCR reaction would generate a product with a profile of 168 and 227 bp, respectively. To investigate the accuracy and limit of detection, an in vitro experiment was conducted using simplex and duplex PCR on commercial meatballs randomly purchased from a commercial market in Surakarta, Indonesia. The findings of this study indicated that ND2 could be used as an alternative genetic marker for the identification of porcine and beef species in meat-derived products.

16.
Zookeys ; 1168: 367-386, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37448483

RESUMEN

Among the six species of Cyrtodactylus occurring in Sumatra, two species were described based on non-Sumatran type series, C.consobrinus and C.quadrivirgatus. The latter species was described originally from Thailand thus the wider distribution in Sumatra should be clarified taxonomically. Cyrtodactylusquadrivirgatus from Sumatra Barat was examined using both morphology and the Natrium Dehydrogenase Subunit 2 (ND2) gene to clarify its taxonomic status and phylogenetic placement. It was found that these specimens form a sister clade to all other species of the sworderi group from Peninsular Malaysia and the genetic distance ranges from 20-24.3%. This subset is herein described as a new species. The new species is readily distinguished from C.quadrivirgatus and other Sumatran species by a combination of characters: small size SVL 37.5-53.78 mm; longitudinal rows of dorsal tubercles 16-19; paravertebral tubercles 31-41; ventral scales 32-43; 24-49 enlarged precloacal and femoral scales; precloacal pores rarely present; no precloacal depression; two postcloacal tubercles on each side; 14-19 subdigital lamellae on forth toe; 9-15 supralabial scales; 9-12 infralabial scales; three or four internasal scales; and 3-6 gular scales that border the first pair of postmental scales. This work underscores the importance of clarifying widely distributed species for taxonomic validation.

17.
Environ Pollut ; 334: 122191, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37451587

RESUMEN

The widespread use of neodymium oxide nanoparticles (NPs-Nd2O3) has caused environmental pollution and human health problems, thus attracting significant attention. Understanding the mechanisms of NPs- Nd2O3-induced genetic damage is of great significance for identifying early markers for NPs- Nd2O3-induced lung injury. At present, the mechanisms underlying DNA damage induced by NPs- Nd2O3 remain unclear. In this study, we performed functional assays on human bronchial epithelial cells (16HBEs) exposed to various concentrations of NPs-Nd2O3 and SD rats administered with a single intratracheal instillation with NPs-Nd2O3. Exposure to NPs-Nd2O3 could lead to DNA damage in 16HBE cells and rat lung tissue cells. We found a novel long non-coding RNA, named CNTFR-AS1, which was highly expressed after exposure to NPs-Nd2O3. Our data verified that transcription factor TP63 mediates the high expression levels of CNTFR-AS1, which in turn regulates NPs-Nd2O3-induced DNA damage in cells by inhibiting HR repair. Moreover, the levels of CNTFR-AS1 were correlated with the number of years worked by occupational workers. Collectively, these results demonstrate that CNTFR-AS1 acts as a novel DNA damage regulator in bronchial epithelial cells exposed to NPs-Nd2O3. Hence, our data provide a basis for the identification of lncRNAs as early diagnostic markers for rare earth lung injury.


Asunto(s)
Lesión Pulmonar , Nanopartículas , ARN Largo no Codificante , Humanos , Animales , Ratas , ARN Largo no Codificante/genética , Factores de Transcripción , Reparación del ADN por Recombinación , Ratas Sprague-Dawley , Daño del ADN , Proteínas Supresoras de Tumor , Subunidad alfa del Receptor del Factor Neurotrófico Ciliar
18.
Environ Sci Pollut Res Int ; 30(32): 78332-78338, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37269512

RESUMEN

Nanoparticulate-Nd2O3 (nano-Nd2O3) has been excessively utilized in agriculture, industry, and medicine. Hence, nano-Nd2O3 can have environmental implications. However, the impact of nano-Nd2O3 on alpha diversity, composition, and function of soil bacterial communities has not been thoroughly evaluated. We amended soil to achieve different concentrations of nano-Nd2O3 (0, 10, 50, and 100 mg kg-1 soil) and incubated the mesocosms for 60 days. On days 7 and 60 of the experiment, we measured the effect of nano-Nd2O3 on alpha diversity and composition of soil bacterial community. Further, the effect of nano-Nd2O3 on the function of soil bacterial community was assessed based on changes in the activities of the six potential enzymes that mediate the cycling of nutrients in the soil. Nano-Nd2O3 did not alter the alpha diversity and composition of the soil bacterial community; however, it negatively affected community function in a dose-dependent manner. Specifically, the activities of ß-1,4-glucosidase and ß-1,4-n-acetylglucosaminidase that mediate soil carbon and nitrogen cycling, respectively, were significantly affected on days 7 and 60 of the exposure. The effect of nano-Nd2O3 on the soil enzymes correlated with changes in relative abundances of the rare and sensitive taxa, viz., Isosphaerales, Isosphaeraceae, Ktedonobacteraceae, and Streptomyces. Overall, we provide information for the safe implementation of technological applications that use nano-Nd2O3.


Asunto(s)
Chloroflexi , Suelo , Microbiología del Suelo , Agricultura , Bacterias
19.
Nanomaterials (Basel) ; 13(10)2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37242079

RESUMEN

The following investigation presents the thermal treatment of geopolymer at 300 °C, 600 °C and 900 °C. We investigated what happens to the geopolymer base when incorporated with 1% and 5% of neodymium in the form Nd2O3. A total of six samples were synthesized. Geopolymer 1 contained 1% and geopolymer 2 contained 5% Nd2O3, and these samples were treated at 300 °C; then, samples geopolymer 3 and geopolymer 4 also had the same percentage composition of Nd2O3 and were treated at 600 °C, while samples geopolymer 5 and geopolymer 6were treated at 900 °C. Physical and chemical changes in the aluminosilicate geopolymer matrix were monitored. The incorporation of rare earths into the polymer network of aluminosilicates has been proven to disrupt the basic structure of geopolymers; however, with increased temperatures, these materials show even more unusual properties. Diffuse reflectance infrared Fourier transform (DRIFT) analysis showed that the intensity of the vibrational band decreases with the increase in temperature during thermal treatment, suggesting alterations in the chemical structure of the geopolymers. Transmission electron microscopy (TEM) analysis showed that the diameter of the nanoparticles containing Al2O3 is in the range 5-10 nm, while larger crystallites range from 30 to 80 nm. Scanning electron microscopy (SEM) analysis revealed that the temperature of the thermal treatment increases to 300 °C and 600 °C; the porosity of geopolymer increases in the form of the appearance of large pores and cracks in material. X-ray photoelectron spectroscopy (XPS) analysis was used to investigate the surface chemistry of geopolymers, including the chemical composition of the surface, the oxidation state of the elements, and the presence of functional groups. The UV/Vis spectra of the synthesized geopolymers doped with Nd3+ show interesting optical properties at 900 °C; the geopolymer matrix completely disintegrates and an amorphous phase with a rare-earth precipitate appears.

20.
Zookeys ; 1148: 167-207, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37235140

RESUMEN

Four new species of Diploderma are described from Sichuan and Yunnan provinces, southwestern China, based on an integrative taxonomic approach, combining morphological and genetic data. The first new species from Danba County, Sichuan Province, is morphologically most similar and phylogenetically closely related to D.flaviceps, but it can be diagnosed from the latter by having a relatively much shorter tail and by a genetic distance of 4.4% in the ND2 gene; the second new species from Muli County, Sichuan Province, is phylogenetically closely related to D.daochengense, D.yongshengense, and D.yulongense, but it can be diagnosed from the latter three species by having a pale yellow gular spot and by genetic distances of 5.6-6.7% in the ND2 gene; the third new species from Jiulong County, Sichuan Province, is morphologically most similar and phylogenetically closely related to D.angustelinea, but it can be diagnosed from the latter by having a relatively much longer tail and by a genetic distance of 2.8% in the ND2 gene; and the last new species from Weixi County, Yunnan Province, is phylogenetically closely related to D.aorun, but it can be diagnosed from the latter by having a pale yellow gular spot and by a genetic distance of 2.9% in the ND2 gene. Our work brings the number of species within the genus Diploderma to 46.

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