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1.
Zookeys ; 1104: 177-201, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761927

RESUMO

Caridinastellata sp. nov. is described from streams in Guangxi, south-western China. The new species clearly belongs to "Caridinaserrata group" of the genus and shows a morphological similarity with C.cantonensis Yu, 1938, C.serrata Stimpson, 1860 and C.pacboDo et al. 2020. Caridinastellata is distinguished from congeners, based on differences in its male first pleopod and appendix masculina morphology, along with COI and 16S rRNA molecular evidence. The first pleopod endopod in male is rectangle, about 0.70 × length of exopod, about 3.7-3.9 × as long as proximally wide, inner margin concave, bearing nearly equal spine setae, outer margin bearing nearly equal long and dense spine setae; appendix interna well developed, arising from distal 1/5 of endopod, reaching to end of endopod, with cincinuli distally. The new species displays a unique and brightly coloured pattern and, therefore, can be easily recognised in the field. Liang & Zhou, 1993 described C.cavernicola from the Lenggu Cave, Du'an County, Guangxi. However, the description was based exclusively on two females. We have collected specimens of both sexes near the type locality and describe herein the previously unknown male and present morphological data on females. Data on the habitat, ecology and levels of threat of the two species are provided and suggest that they should be categorised as vulnerable (VU) under the current IUCN Criteria.

2.
Zookeys ; 1028: 29-47, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33883966

RESUMO

Collecting much-needed information on the taxonomy, distribution, and ecology of cave-dwelling shrimp is vital for addressing the urgent challenges in conservation biodiversity in fragile cave ecosystems. Caridina incolor sp. nov., a new atyid shrimp from an underground stream of Yaoshui Cave, Daqikong scenic area, Libo County, Guizhou Province, southwestern China is described based on morphology and DNA analysis (mitochondrial COI). Caridina incolor sp. nov. differs from epigean congeners by its smaller eyes which range from reduced to completely blind; colorless body and appendages; long stylocerite and sixth abdominal segment; and relatively large eggs. In comparison to other cave species, Caridina incolor sp. nov. presents a long rostrum and stylocerite; slender sixth abdominal segment; and unique shape of the appendix masculina. Data on the habitat, ecology, and levels of threat are provided and suggest that it should be categorized as Critically Endangered (CR) under the current IUCN criteria.

3.
Nanomaterials (Basel) ; 10(10)2020 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-33020438

RESUMO

Photocatalytic hydrogen peroxide (H2O2) production has attracted considerable attention as a renewable and environment-friendly method to replace other traditional production techniques. The performance of H2O2 production remains limited by the inertness of graphitic carbon nitride (CN) towards the adsorption and activation of O2. In this work, a photocatalyst comprising of ß-cyclodextrin (ß-CD)-modified CN with supporting Au co-catalyst (Au/ß-CD-CN) has been utilized for effective H2O2 production under visible light irradiation. The static contact angle measurement suggested that ß-CD modification increased the hydrophobicity of the CN photocatalyst as well as its affinity to oxygen gas, leading to an increase in H2O2 production. The rate of H2O2 production reached more than 0.1 mM/h under visible-light irradiation. The electron spin resonance spectra indicated that H2O2 was directly formed via a 2-electron oxygen reduction reaction (ORR) over the Au/ß-CD-CN photocatalyst.

4.
Zootaxa ; 4759(4): zootaxa.4759.4.3, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33056893

RESUMO

Based on morphological, molecular, and ecological evidences, a fourth species of cave-dwelling shrimp Macrobrachium tenuipes sp. nov. is described from Guangxi Zhuang Autonomous Region, southwestern China. This new species with smooth carapace and the extremely slender pereiopods, can be separated from other congeners by the shape of rostrum; the segmental ratios, the arrangement of teeth on the cutting edge of the fingers of second pereiopod; the longer and narrower scaphocerite; and the longer uropodal diaeresis spine. The new taxon is genetically distinct from 18 other species of Macrobrachium for which COI and 18S rRNA sequences are available. The data observed on the habitat and ecology will contribute to the conservation for M. tenuipes sp. nov.


Assuntos
Decápodes , Palaemonidae , Animais , Cavernas , China , Água Doce
5.
PLoS One ; 15(9): e0234835, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881864

RESUMO

In this study, the physiological values of volumes of plasma, cells, total blood and the F blood factors were identified in 24 adult tree shrews (Tupaia belangeri; 12 male and 12 female; average BW of 123.9±19.19 g). The two-compartment model method of Evans Blue dye was used to obtain the plasma volume and the venous hematocrit was measured by microhematocrit method. To establish the relationship between body weight (BW) and blood volume of tree shrews, We performed linear fitting for these two datasets. Results were analyzed according to gender and weight (<120g vs.>120g). Statistical significance was assessed using the unpaired student t test and one-way ANOVA. The average volumes per 100g body weight of plasma, red blood cell (RBC) and total blood were 5.42±0.543, 3.24±0.445, and 8.66±0.680ml respectively. The mean body hematocrit, cardiac hematocrit, jugular vein hematocrit, femoral vein hematocrit, and tail vein hematocrit was 37.43±4.096, 39.72±3.219, 43.04±4.717, 40.84±3.041, and 38.71±3.442% respectively. The F cardiac was 0.94±0.072, F jugular vein 0.88±0.118, F femoral vein 0.92±0.111, and the F tail vein 0.97±0.117. Blood volume (ml) was 85.89103×BW (kg). This is the first study to provide the parameters of plasma volume, cell volume, total blood volume and F factor and a baseline for future research on blood physiology of tree shrews.


Assuntos
Tupaiidae/sangue , Animais , Volume Sanguíneo , Peso Corporal , Tamanho Celular , Feminino , Hematócrito , Masculino , Volume Plasmático , Tupaiidae/fisiologia
6.
Zookeys ; 923: 15-32, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32292268

RESUMO

A faunistic and ecological survey was conducted to document the diversity of freshwater atyid shrimps of Dawanshan Island. Two species of Caridina that occur on this island were documented and discussed. One of these, Caridina tetrazona sp. nov. is described and illustrated as new to science. It can be easily distinguished from its congeners based on a combination of characters, which includes a short rostrum, the shape of the endopod of the male first pleopod, the segmental ratios of antennular peduncle and third maxilliped, the slender scaphocerite, and the absence of a median projection on the posterior margin. Live individuals of the new species display a unique coloration pattern with four dark blue transverse bands on the body, and can be easily recognized in the field. So far, despite considerable surveying efforts made on neighboring islands, this species has only been found from a small stream on Dawanshan Island, which suggests that it may have a very limited range, probably endemic to Dawanshan Island. Molecular characteristics of the mitochondrial cytochrome c oxidase subunit I (COI) demonstrate that this species shows sufficient interspecific divergence from its congeners, including C. serrata Stimpson, 1860, which was found in four streams on Dawanshan Island, and has been previously reported on the neighboring islands of Hong Kong, Dong'ao, Wailingding, and Guishan.

7.
Zookeys ; 1008: 17-35, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33505186

RESUMO

From a biodiversity survey of a subterranean habitat near Sinan County, Guizhou Province, southwestern China, a new atyid shrimp of the genus Caridina H. Milne Edwards, 1837, C. sinanensis sp. nov. was discovered. The new species can be separated from other congeners based on a combination of characters including depigmentation in body and reduction of eyes, small pigment spot at the centre of the cornea, the shape of rostrum and the endopod of the 1st male pleopod, and the relatively longer appendix interna on the appendix masculina of the 2nd pleopod. Mitochondrial COI and 16S rRNA gene sequences also support the establishment of the new species. Information on the habitat, and the levels of threat are discussed to guide the conservation of C. sinanensis sp. nov.

8.
J Biomed Mater Res B Appl Biomater ; 108(3): 1077-1084, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31389156

RESUMO

An oxidized, porous graphitic carbon nitride nanosheets (CNNs) was successfully obtained via a bottom-up approach. The inner filter effect (IFE) of Fe (III) tetrakis (1-methyl-4-pyridyl) porphyrin pentachlorideporphyrin pentachloride (FeTMPyP) on the CNNs results in fluorescence quenching of the CNNs due to the overlap of FeTMPyP absorbance band and CNNs emission band. It is interesting that the quenched fluorescence could be "turned on" in response to the participation of H2 O2 , which caused by decomposition of FeMPyP. In this study, for the first time, a porous fluorescence probe based on CNNs and FeTMPyP was designed and an excellent H2 O2 detection performance with a large detection range of 0.1 ~ 100 µM and a detection limit of 0.07 µM was achieved. Furthermore, the proposed method was successfully used for H2 O2 detection in RAW 264.7 cells.


Assuntos
Corantes Fluorescentes/química , Peróxido de Hidrogênio/química , Metaloporfirinas/química , Nanoestruturas/química , Oxigênio/química , Animais , Sobrevivência Celular , Grafite , Camundongos , Nanotecnologia/instrumentação , Compostos de Nitrogênio , Porosidade , Porfirinas/química , Células RAW 264.7 , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Ureia/química , Difração de Raios X
9.
Zookeys ; 866: 65-83, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31388323

RESUMO

Evidence-based information is the foundation for addressing urgent global challenges in conservation and sustainable management of the freshwater biodiversity. The present study expands current knowledge of the genus Macrobrachium in Zaomu Mountain Forest Park, Guangdong Province based on the morphology, colouration, distribution, and molecular characteristics of Macrobrachiummaculatum, M.inflatum, M.nipponense, and an undescribed new species, M.laevis. Macrobrachiumlaevis sp. nov. can be distinguished from its congeners by a combination of characters, which includes the shape of rostrum, smooth carapace, and male second pereiopod. Macrobrachiumlaevis sp. nov. displays striking colour pattern, which could help to distinguish this species from other congeneric species in living specimen. Furthermore, the molecular characteristics of mitochondrial cytochrome c oxidase subunit I (COI) showed that this species has a sufficient interspecific divergence from its congeners.

10.
J Mater Sci Mater Med ; 29(12): 184, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30515626

RESUMO

The original version of this article unfortunately contained a mistake. In the Abstract section the sentence "Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process cohydroxyapatite/methotrexate complexntrolled by gradient drug concentration." was wrong. It should read as "Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process controlled by gradient drug concentration."

11.
Zootaxa ; 4472(3): 532-544, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30313360

RESUMO

Yuelu mountain national park (5A scenic area) is a rare urban mountain scenic area. The major impacts from human activity are growing, such as largely unplanned tourist activity, urbanization, and accelerated the others responsible for environmental changes. It is unavoidable to have great pressure and influence on the diversity of fauna on the scenic area. In order to better understand the diversity of the decapod fauna in the Yuelu mountain national park, an intensive field survey has been carried out. A total of five species was collected, three species of atyid shrimps, Neocaridina palmata (Shen, 1948), N. yueluensis, new species, and Paracaridina longispina (Guo He, 1992), one species of palaemonid prawn, Macrobrachium nipponense (De Haan,1849), and an invasive crayfish, Procambarus clarkii (Girard, 1852). N. yueluensis is distiguished from congeners by the shorter rostrum, the stout carpus of first pereiopod and the stout chela of second pereiopod, not sexual dimorphism of the third and fourth pereiopods, the long appendix interna and arising from the inner border of appendix masculina, and the narrower scaphocerite.


Assuntos
Astacoidea , Animais , China , Decápodes , Masculino , Palaemonidae , Parques Recreativos , Caracteres Sexuais
12.
J Mater Sci Mater Med ; 29(8): 116, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-30027359

RESUMO

In this study, g-C3N4/methotrexate (g-C3N4/MTX) nanohybrids were obtained via a self assembly method. XRD and TEM demonstrated that bulk g-C3N4 had been stripped into thin nanosheets with size range of 150-250 nm. FTIR investigation indicated that the self assembly of the hybrid was attributed to the hydrogen bond between g-C3N4 nanosheets and MTX molecules. It is confirmed by the UV-vis spectra that the hybrids can achieve a sustained drug release within long period for 70 h. Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process cohydroxyapatite/methotrexate complexntrolled by gradient drug concentration. Cell viability tests confirmed that g-C3N4 presented excellent biocompatibility and g-C3N4/MTX hybrids had obvious suppression efficiency on MG63 cells which showed a positive correlation to the drug concentration and incubation time.


Assuntos
Sistemas de Liberação de Medicamentos , Grafite/química , Metotrexato/química , Nanopartículas/química , Nitrilas/química , Antineoplásicos/administração & dosagem , Bioensaio , Linhagem Celular Tumoral , Preparações de Ação Retardada , Difusão , Liberação Controlada de Fármacos , Durapatita/química , Humanos , Teste de Materiais , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Triazinas/química , Difração de Raios X
13.
Zootaxa ; 4399(3): 315-328, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29690315

RESUMO

The present study, based on a faunistic and ecological survey of caridean shrimps from Dong'ao Island, Guangdong Province, expands the knowledge of morphology, colouration, and distribution of three species, two of which belong to genus Caridina and one belong to genus Marcrobrachium. Caridina zhujiangensis, new species is distinguished from the closely related species C. typus H. Miline Edwars,1837 by shorter rostrum and with only one ventral margin teeth, the shape of the endopod of the first male pleopod and the appendix interna arising from distal 1/3 of endopod. Macrobrachium dongaoensis, new species, can be distinguished from its congeners M. inflatum Liang Yan, 1985 by a combination of characters which includes short rostrum, the subequal male second pereiopods, the non-inflated palm, and the longer merus. A diagnosis of three speciesmore and full description of two new species are presented.


Assuntos
Decápodes , Distribuição Animal , Estruturas Animais , Animais , Tamanho Corporal , China , Ilhas , Quênia , Masculino , Tamanho do Órgão
14.
Rev Sci Instrum ; 84(4): 043908, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23635210

RESUMO

An experimental technique for metal expanding ring subjected to high explosive loading is conducted to significantly improve the loading stability compared with the traditional setup of two-end detonator initiation. Aspects of the circuit design, experimental arrangement, and initiation principle are illustrated in great detail. In terms of this experimental platform, we examine the velocity response of an individual ring, which demonstrates the experimental reproducibility. Moreover, fragmentation of multiple rings stacked on a metal driver is discussed.

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