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1.
J Chem Ecol ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600408

RESUMO

Spraying urine on vertical objects by raising the tail is a commonly observed functional behavior for chemical communication in Felidae species, including domestic cats (Felis silvestris catus). The sprayed urine is recognized as a chemical signal for territorial ownership of their habitats. Previous studies reported that sprayed urine emits a more pungent odor than urine excreted from a squatting position. However, little is known about how sprayed urine acts as a strong scent mark in the environment. Here, we showed that sprayed urine originates only from bladder urine without any secretions, such as anal sac secretions, but it can effectively emit volatile organic compounds (VOCs) when smeared on vertical objects due to its strong adhesion. Chemical profiles of VOCs and odor qualities were similar between fresh sprayed urine and bladder urine sampled immediately after spraying from the same individuals. Meanwhile, feline-specific proteinuria arising from excretion of a carboxylesterase that produces a precursor of cat-specific odorants resulted in reduced surface tension of the urine and increased adhesion to vertical surfaces, which kept sprayed urine on the surfaces and led to the emission of large amounts of VOCs. In conclusion, proteinuria contributes to the emission of a strong odor through its enhanced adhesion to vertical objects without other secretions containing malodorous substances. These findings improve our understanding of the mechanism of scent marking via the spraying of urine for chemical communication in cats.

2.
Nanoscale ; 16(1): 474-487, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38086669

RESUMO

Vacancy engineering offers an appealing strategy for modifying the electronic structure of transition metals. Transition metals with abundant sulfur vacancies can significantly contribute to the microwave absorption capabilities of absorbers. In this study, an NixSy@De composite material was synthesized through a straightforward hydrothermal synthesis technique. The effective absorption bandwidth (EAB) of this composite material reached 9.86 GHz at 1.44 mm. A minimum reflection loss (RLmin) of -33.61 dB at 1 mm was achieved, and after mild etching, the RLmin further improved to -93.53 dB at 1.16 mm to achieve a high-attenuation microwave absorption. The exceptional performance of NixSy@De for the absorption of electromagnetic waves (EMWs) is based on its high dielectric loss, substantial magnetic loss, and excellent impedance matching. This work combines transition metal sulfides with three-dimensional biotemplated diatomite, providing valuable insights into the design of advanced EMW absorbing materials.

3.
Chemphyschem ; 24(20): e202300292, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37491736

RESUMO

The 1 H nuclear magnetic resonance (1 H-NMR) spectrum is a useful tool for characterizing the hydrogen bonding (H-bonding) interactions in ionic liquids (ILs). As the main hydrogen bond (H-bond) donor of imidazolium-based ILs, the chemical shift (δH2 ) of the proton in the 2-position of the imidazolium ring (H2) exhibits significant and complex solvents, concentrations and anions dependence. In the present work, based on the dielectric constants (ϵ) and Kamlet-Taft (KT) parameters of solvents, we identified that the δH2 are dominated by the solvents polarity and the competitive H-bonding interactions between cations and anions or solvents. Besides, the solvents effects on δH2 are understood by the structure of ILs in solvents: 1) In diluted solutions of inoizable solvents, ILs exist as free ions and the cations will form H-bond with solvents, resulting in δH2 being independent with anions but positively correlated with ßS . 2) In diluted solutions of non-ionzable solvents, ILs exist as contact ion-pairs (CIPs) and H2 will form H-bond with anions. Since non-ionizable solvents hardly influence the H-bonding interactions between H2 and anions, the δH2 are not related to ßS but positively correlated with ßIL .

4.
Chemosphere ; 333: 138989, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37209844

RESUMO

The rapid expansion of biomass power generation has resulted in a large amount of ash, which need to be treated urgently. The trace elements in ash also have environmental risks during treatment. Therefore, the essential characteristics and potential environmental risks of biomass ash generated by direct combustion of agricultural straw were studied. The leaching characteristics of elements, including major elements (Mg, K, Ca) and trace elements (V, Cr, Mn, Co, Ni, Cu, Zn, Cd, As, Pb and Ba), in fly ash and slag produced by biomass power plant were analyzed through the static leaching experiments of simulating the possible pH value of natural water in the laboratory. The results show that the trace elements are enriched in fly ash and slag, which may be related to the volatility of elements during combustion. And during the leaching test, the leaching concentration of major and trace elements in fly ash is higher than that in slag. Sequential chemical extraction is used to reveal the occurrence forms of trace elements in biomass ash. Except for residue, Mn, Co, Zn, Cd, and Pb in fly ash mainly exist in carbonate bound, V and As are Fe-Mn oxides bound, and Cr, Ni, Cu, and Ba are mainly organic matter bound. In the slag, Cd is mainly carbonate bound, Cu is mainly organic matter bound, while other elements are mainly Fe-Mn oxides bound. The Risk Assessment Code values calculated based on the existing forms of elements show that As and Cd in slag and Mn, Co, Pb and Cd in fly ash need special attention during utilization. The research results can provide reference for the management and utilization of biomass ash.


Assuntos
Cinza de Carvão , Oligoelementos , Cinza de Carvão/química , Biomassa , Oligoelementos/análise , Cádmio , Chumbo , Óxidos , Centrais Elétricas
5.
Environ Res ; 231(Pt 1): 116070, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37150388

RESUMO

It is possible to achieve high-value utilization of solid wastes and lower the cost of mesoporous silica synthesis by synthesizing mesoporous silica from solid wastes. In this study, silica was extracted using the alkali fusion method using biomass ash as the starting material. Biomass ash based mesoporous silica was successfully prepared by hydrothermal method with silicon extract solution as silicon source. The optimum conditions for preparation were determined as follows: addition of cetyltrimethylammonium bromide was 0.45g, hydrothermal temperature was 120 °C, hydrothermal time was 24h. The prepared mesoporous silicon was systematically characterized, and the results showed that high surface area (495 m2/g) and ordered pore structure appeared in the synthesized mesoporous silica materials. The synthesized mesoporous silica showed excellent CO2 adsorption performance (0.749 mmol/g) at 25 °C and 1 bar. According to the calculation of adsorption isotherm and thermodynamics, non-linear Freundlich model can fit the adsorption isotherm better and the adsorption heat of mesoporous silica is less than 20 kJ/mol, which belongs to physical adsorption. After five cycles of CO2 adsorption, the adsorption property was still above 90%, and the CO2/N2 adsorption selectivity reached 396.6, showing good regeneration performance and adsorption selectivity. This research can provide a new possibility for the high-value exploitation of biomass ash and reducing the cost of synthetic mesoporous silica.


Assuntos
Dióxido de Silício , Resíduos Sólidos , Dióxido de Silício/química , Dióxido de Carbono/química , Silício , Adsorção , Biomassa
6.
Biol Reprod ; 109(1): 97-106, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37140246

RESUMO

The zona pellucida (ZP) is an extracellular matrix that surrounds all vertebrate eggs, and it is involved in fertilization and species-specific recognition. Numerous in-depth studies of the ZP proteins of mammals, birds, amphibians, and fishes have been conducted, but systematic investigation of the ZP family genes and their role during fertilization in reptiles has not been reported to date. In this study, we identified six turtle ZP (Tu-ZP) gene subfamilies (Tu-ZP1, Tu-ZP2, Tu-ZP3, Tu-ZP4, Tu-ZPD, and Tu-ZPAX) based on whole genome sequence data from Mauremys reevesii. We found that Tu-ZP4 had large segmental duplication and was distributed on three chromosomes, and we also detected gene duplication in the other Tu-ZP genes. To evaluate the role of Tu-ZP proteins in sperm-egg binding, we assessed the expression pattern of these Tu-ZP proteins and their ability to induce the spermatozoa acrosome reaction in M. reevesii. In conclusion, this is the first report of the existence of gene duplication of Tu-ZP genes and that Tu-ZP2, Tu-ZP3, and Tu-ZPD can induce acrosome exocytosis of spermatogenesis in the reptile.


Assuntos
Reação Acrossômica , Tartarugas , Animais , Masculino , Acrossomo/metabolismo , Proteínas do Ovo/genética , Mamíferos/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Répteis/metabolismo , Sêmen/metabolismo , Espermatozoides/metabolismo , Tartarugas/genética , Zona Pelúcida/metabolismo , Glicoproteínas da Zona Pelúcida/genética , Glicoproteínas da Zona Pelúcida/metabolismo , Feminino
7.
Phys Chem Chem Phys ; 22(37): 20995-20999, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32955049

RESUMO

Whether the reaction pathway is steady or dynamic over the whole life cycle of a catalyst process can facilitate our understanding of its catalytic behavior. Herein, the dynamic reaction pathways of nitrogen-doped carbon catalysts are investigated in acetylene hydrochlorination. When triggered, the reaction follows the Langmuir-Hinshelwood mechanism with pyrrolic N and pyridinic N as dual active sites. However, pyridinic N is deactivated first, due to the strong adsorption of hydrogen chloride, causing the reaction to further run with pyrrolic N as the single active site and follow the Eley-Rideal mechanism. This work provides a new promising way to study the catalytic behavior of nitrogen-doped carbon catalysts.

8.
J Ethnopharmacol ; 185: 282-8, 2016 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-26940899

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Huangliang Xiangru Decoction (HXD), which is described in a famous TCM monograph "Book of Nanyang for Life Savin", is frequently used for treating cold in summer and summer heat-dampness. AIM OF THE STUDY: To date, no pharmacological study on the anti-H1N1 influenza properties of HXD has been reported. The aim of the present study was to evaluate the therapeutic action of HXD on HIN1-induced acute pulmonary inflammation and its anti-influenza mechanism focus to TLRs signal pathway in a mouse model. MATERIALS AND METHODS: the mice were intranasally infected with influenza virus to induce viral pneumonia, and then treated with different doses of HXD. The Lung index and pathological changes in the lung tissue of mice were investigated to value the anti-influenza virus effect of HXD. The concentrations of cytokines (IL-2, IL-6, TNF-α and IFN-γ) and anti-oxidant factor (NO, SOD and GSH) in serum of mice were determined with ELISA. RT-PCR and Western blot were used to determine the mRNA and protein expression of TLR3, TLR7, MyD88,TRAF3 and NF-κB p65 in the lung tissues, which are the key targets of TLRs pathway. RESULTS: Compared with the infection group, the lung index of mice in ribavirin group, HXD high dose group and HXD middle dose group were significantly decreased, the lung indexes of these groups were 10.36±1.14mg/g, 9.89±0.79mg/g, and 10.97±0.67mg/g. Moreover, pathological changes were remarkable alleviated. HXD can reduce the contents of IL-6, TNF-α and IFN-γ, NO, and increase the contents of IL-2, SOD, GSH in serum of infected-mice significantly. At the same time, HXD can reduce the mRNA and protein expression of TLR3, TLR7, MyD88,TRAF3 and NF-κB p65 in the lung tissues of infected-mice significantly. CONCLUSIONS: HXD has significant effects on H1N1 influenza by a quantity-effect relationship, and plays its anti-influenza effect by enhancing the body's antioxidant capacity, regulating the body's immune function and the host's TLRs pathway.


Assuntos
Antivirais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Infecções por Orthomyxoviridae/tratamento farmacológico , Animais , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Camundongos , Camundongos Endogâmicos ICR , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Organismos Livres de Patógenos Específicos
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 33(4): 698-706, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-29714909

RESUMO

Light emitting diode(LED)can be used in the treatment of jaundice.Blue and green LED irradiation affected with the newborn is currently considered the most effective treatment of the jaundice in the world.A jaundice phototherapy system with blue and green LED as light source utilizing fly eye lens array was built to achieve uniform illumination in the present study.AMC7150 chip was used to build the constant current drive module,and AT89C52 MCU and LCD12864 LCD screen were used to build the human-computer interaction module.Based on national particular phototherapy equipment requirements(YY0669-2008)for the safety,we designed and implemented a phototherapy system which spot area was 250mm×500mm,blue light irradiance reached 2mW/cm2,green light irradiance reached 1.5mW/cm2,and the uniformity of light was over 90%.Compared with the traditional system,the new one designed in this study has better therapeutic effect,higher biological safety,easier to achieve man-machine interaction,and more economical and convenient.


Assuntos
Icterícia/terapia , Cristalino , Luz , Fototerapia/instrumentação , Animais , Cor , Drosophila , Desenho de Equipamento , Humanos , Recém-Nascido , Masculino
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