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1.
Ying Yong Sheng Tai Xue Bao ; 34(9): 2429-2435, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37899109

RESUMO

The three provinces of Northeast China are crucial to national commodity grain production. Soils in those areas have begun to severely degrade after long-term high-intensity use, with wind erosion as one of the main reasons. Based on meteorological and soil data from 1981 to 2019, we evaluated the spatial-temporal characteristics of wind erosion on bare land in the three provinces of Northeast China by using the revised wind erosion equation (RWEQ), and analyzed the contributions of meteorological factors to wind erosion on bare land. The results showed that, the meteorological factors of wind erosion were overall high in southwestern part and low in northeastern part of the region. In general, wind erosion in the region was substantial, especially in Liaoning. During the 39 years, wind erosion significantly increased throughout the whole year and during the growing season, at a rate of 129 and 105 t·km-2 per decade, respectively. The obvious increase in wind erosion was observed in the northwest Liaoning, Liaohe Plain, and Changbai Mountain area. Wind speed and air temperature were the main factors affecting wind erosion during the year and non-growing season, which contributed less during the growing season when precipitation contributed the most. We concluded that climate change has aggravated soil wind erosion in the three provinces of Northeast China.


Assuntos
Mudança Climática , Vento , Solo , China , Temperatura
3.
Org Lett ; 25(17): 2964-2969, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37079388

RESUMO

Direct dehydroxytrifluoromethylthiolation of alcohols is an attractive strategy for accessing CF3S-containing compounds. Herein, we report a method for dehydroxytrifluoromethylthiolation of alcohols by using the combination of hypervalent iodine(III) reagent TFTI and N-heterocyclic carbenes. This method shows excellent stereospecificity and chemoselectivity to give a product with clean inversion of the configuration of hydroxyl groups as well as can be used for late-stage modification of structurally complex alcohols. The reaction mechanism is proposed with experimental and computational evidence.

4.
Nature ; 611(7936): 485-490, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36224388

RESUMO

Lithium-ion batteries with nickel-rich layered oxide cathodes and graphite anodes have reached specific energies of 250-300 Wh kg-1 (refs. 1,2), and it is now possible to build a 90 kWh electric vehicle (EV) pack with a 300-mile cruise range. Unfortunately, using such massive batteries to alleviate range anxiety is ineffective for mainstream EV adoption owing to the limited raw resource supply and prohibitively high cost. Ten-minute fast charging enables downsizing of EV batteries for both affordability and sustainability, without causing range anxiety. However, fast charging of energy-dense batteries (more than 250 Wh kg-1 or higher than 4 mAh cm-2) remains a great challenge3,4. Here we combine a material-agnostic approach based on asymmetric temperature modulation with a thermally stable dual-salt electrolyte to achieve charging of a 265 Wh kg-1 battery to 75% (or 70%) state of charge in 12 (or 11) minutes for more than 900 (or 2,000) cycles. This is equivalent to a half million mile range in which every charge is a fast charge. Further, we build a digital twin of such a battery pack to assess its cooling and safety and demonstrate that thermally modulated 4C charging only requires air convection. This offers a compact and intrinsically safe route to cell-to-pack development. The rapid thermal modulation method to yield highly active electrochemical interfaces only during fast charging has important potential to realize both stability and fast charging of next-generation materials, including anodes like silicon and lithium metal.

5.
Biomed Environ Sci ; 35(8): 681-687, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36127780

RESUMO

Objective: This study is to obtain precise data on iron physiological requirements in Chinese children using single stable isotope tracer technique. Methods: Thirty boys (10.6 ± 0.2 years) and 27 girls (10.4 ± 0.2 years) were received oral 6 mg 57Fe each day for 5 consecutive days. Venous blood samples were subsequently drawn to examine the change of total iron concentration and 57Fe abundance at day 0, 14, 28, 60, 90, 180, 360, 450, 540, 630, 720. The iron physiological requirement was calculated by iron loss combined with iron circulation rate once 57Fe abundance stabilized in human body. Results: The iron physiological requirement was significantly lower in boys than those values in girls (16.88 ± 7.12 vs. 18.40 ± 8.81 µg/kg per day, P < 0.05). Correspondingly, the values were calculated as 722.46 ± 8.43 µg/day for boys and 708.40 ± 7.55 µg/day for girls, respectively. Considering nearly 10% iron absorption rate, the estimated average iron physiological requirement was 6.0 mg/day in boys and 6.2 mg/day in girls. Conclusion: This study indicate that iron physiological requirement could require more daily iron intake in girls as compare with the values in boys having the same body weight. These findings would be facilitate to the new revised dietary reference intakes.


Assuntos
Ferro , Estado Nutricional , Peso Corporal , Criança , China , Feminino , Humanos , Isótopos , Masculino
6.
Plants (Basel) ; 11(14)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35890457

RESUMO

The aim of the current study was to evaluate the subchronic toxicity of GmDREB3 gene modified wheat in the third generation rats. SPF Wistar rats were fed with transgenic wheat diet (Gm), parental wheat diet (Jimai22) and AIN-93 rodent diet (Control), respectively, for two generations, to produce the third generation rats which were used for this study. The selected fresh weaned offspring rats (20/sex/group) were given the same diet as their parents for 13 weeks. No toxicity-related changes were observed in rats fed with Gm diet in the following respects: clinical signs, body weights, body weight gains, food consumption, food utilization rate, urinalysis, hematology, serum biochemistry and histopathology. The results from the present study demonstrated that 13 weeks consumption of Gm wheat did not cause any adverse effects in the third generation rats when compared with the corresponding Jimai22 wheat.

7.
Chemistry ; 28(27): e202200272, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35286772

RESUMO

The development of convenient new methods for the synthesis of organic azides is highly desirable. Herein, we report a practical method for dehydroxyazidation of alcohols via an SN 2 pathway involving PPh3 and trifunctional benziodazolone-based hypervalent azido-iodine(III) reagents, which function as an electrophilic center, an azido source, and a base. This mild, chemoselective method was used for late-stage azidation of structurally complex alcohols, as well as for a new synthetic route to the antiepileptic drug rufinamide. The reaction mechanism was also investigated both experimentally and computationally.


Assuntos
Iodo , Álcoois , Azidas , Indicadores e Reagentes , Iodetos
8.
J Orthop Surg Res ; 17(1): 90, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35164817

RESUMO

BACKGROUND: The incidence of osteoporosis and osteoporotic fractures is increasing every year. Traditional Chinese Medicine (TCM) can shed new light on the treatment of osteoporosis. This study aimed to explore the role and mechanism of paeoniflorin in promoting osteogenic differentiation of an osteoblast precursor cell line (MC3T3-E1). METHODS: MC3T3-E1 cells were cultured in osteogenic induction medium (OIM) and OIM combined with different concentrations of paeoniflorin. The optimal dose of paeoniflorin was assessed by a cell counting kit-8 (CCK-8) assay. Then, alkaline phosphatase (ALP) and Alizarin Red S (ARS) staining were performed to assess the osteogenic capacity of paeoniflorin. The transcription of osteogenic genes and the expression of osteogenic proteins were assessed by RT-PCR and Western blotting, respectively. The transcription of Wnt/ß-catenin signaling pathway genes and proteins was assessed by RT-PCR and Western blotting, respectively. Finally, Dickkopf-1 (DKK-1), a Wnt/ß-catenin signaling pathway inhibitor, was used to identify whether the Wnt/ß-catenin signaling pathway was involved in the osteogenic differentiation of paeoniflorin. Osteoclastogenesis in RAW264.7 cells was identified by tartrate-resistant acid phosphatase (TRAP) staining. RESULTS: At concentrations ranging from 0.1 to 100 µM, paeoniflorin was not cytotoxic to MC3T3-E1 cells. Paeoniflorin significantly increased the osteogenic differentiation of MC3T3-E1 cells in a dose-dependent manner. Moreover, paeoniflorin significantly increased osteogenic differentiation gene and protein expression. Through bioinformatic analysis, paeoniflorin-affected genes were found to be involved in different signaling pathways, such as the Wnt/ß-catenin signaling pathway. Paeoniflorin enhanced ß-catenin and CyclinD1 expression compared with that of the control groups. DKK-1 partially reversed the promoting effects of paeoniflorin in promoting osteogenic differentiation of MC3T3-E1 cells. Moreover, paeoniflorin inhibited the osteoclastogenesis of RAW264.7 cells. CONCLUSION: Paeoniflorin promotes osteogenic differentiation in MC3T3-E1 cells by regulating the Wnt/ß-catenin pathway. Paeoniflorin is a potential therapeutic agent for the treatment of osteoporosis.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Diferenciação Celular/efeitos dos fármacos , Glucosídeos/farmacologia , Monoterpenos/farmacologia , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Humanos , Osteoblastos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/genética , beta Catenina/metabolismo
9.
Ying Yong Sheng Tai Xue Bao ; 32(8): 2847-2856, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34664458

RESUMO

To quantitatively assess the satisfaction degree of precipitation on water requirement of table grape in the main producing areas in China, we analyzed the temporal and spatial variations of precipitation, water requirement and water deficit in different growth stages of table grape based on the 1981-2016 daily meteorological data from 429 meteorological stations in the study region (Jinlin and Liaoning of Northeast China; Shanxi and Hebei of North China; Xinjiang, Gansu, Ningxia and Shaanxi of Northwest China; Sichuan, Guizhou and Yunnan of Southwest China; Jiangsu, Shandong, Zhejiang, Anhui, Fujian, Henan, Hubei, Hunan and Guangxi of Southeast China). Results showed that precipitation in each growth stage showed an increasing trend from north to south and from west to east in the study period. The precipitation in germination-flowering stage was the lowest and showed a decreasing trend. The precipitation in maturation-defoliation stage showed a decreasing trend, while that in flowering-veraison and veraison-maturation stage exhibited an increasing trend. Water requirement of grape exhibited an increasing trend in each growth stage in the study region. Water requirement of grape in Xinjiang and the northern of Gansu Province was the highest. The precipitation could not meet water requirement of grape in Xinjiang, northern Gansu, Ningxia, northern Shaanxi, northern Shanxi, northern Hebei, western Liaoning and western Jilin in each growth stage, as well as northern Yunnan and southern Sichuan during germination-flowering stage. In constrast, water surplus was obvious in the other areas, especially in the southeast and southwest of China. The water deficit of grape showed an increasing trend during the germination-flowering and maturation-defoliation stage, while that during flowering-veraison and veraison-maturation stage showed a decreasing trend.


Assuntos
Vitis , China , Estações do Ano , Água
10.
Nutrients ; 13(4)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33923902

RESUMO

Objective: The purpose of this study was to evaluate serum zinc status of pregnant women in the China Adult Chronic Disease and Nutrition Surveillance (CACDNS) in 2015-2016. Methods: A total of 7147 apparently healthy pregnant women were randomly selected in 302 national monitoring sites. Information on age, race, residence region, education, pregnancy, and family income per annum was collected, and the concentration of serum zinc was determined. The evaluation of serum zinc status was further performed according to the recommendations by the International Zinc Nutrition Consultative Group (IZiNCG). Results: The median concentration of serum zinc was 858.9 µg/L with an interquartile range (IQR) of 712.9 µg/L and 1048.9 µg/L, while the overall prevalence of zinc deficiency was 3.5% with a 95% confidence interval (CI) of 3.0% and 3.9%. Serum zinc status of pregnant women changed greatly in the different categories, particular in pregnancy and family income per annum (p < 0.05), but no significant difference was observed in the prevalence of zinc deficiency (p > 0.05). Conclusions: The lower prevalence of zinc deficiency generally indicated a better zinc status for pregnant women in the CACDNS in 2015-2016. However, a well-designed evaluation system of zinc status for pregnant women should be continually optimized and improved by inducing more parameters such as biochemical, dietary, or functional indicators.


Assuntos
Doença Crônica/epidemiologia , Inquéritos Nutricionais , Zinco/sangue , Adolescente , Adulto , China , Feminino , Humanos , Modelos Logísticos , Análise Multivariada , Gravidez , Adulto Jovem , Zinco/deficiência
12.
Oncol Rep ; 45(3): 1306-1314, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33650669

RESUMO

Non­small cell lung cancer (NSCLC) remains an intractable disease, which is primarily due to tumor metastasis and the acquisition of resistance to chemotherapy. Therefore, there is an urgent need for novel therapeutics to overcome these obstacles. It was recently demonstrated that upregulated expression of monoamine oxidase A (MAOA) contributes to the progression of NSCLC. G10, a tumor­targeting representative conjugate of heptamethine carbocyanine dye and an inhibitor of MAOA, was shown to exert potent cytotoxic effects, comparable to those of doxorubicin, against prostate cancer cell lines, as well as moderate MAOA inhibitory activity. The research described herein aimed to extend our previous study on the antitumor function of G10 in NSCLC in vitro and in vivo, and to elucidate the mechanisms through which G10 exerts its antineoplastic effects. G10 markedly inhibited the proliferation of paclitaxel­resistant NSCLC cells (H460/PTX) and reduced tumor cell migration and invasion. Gene expression profiling of paclitaxel­resistant NSCLC cells following treatment with G10 demonstrated that the expression of genes associated with the extracellular matrix was significantly affected, particularly the metastasis­related genes matrix metallopeptidase (MMP)2, MMP14 and COL6A, which exhibited notably reduced expression. Additionally, the results also demonstrated that MAOA­related pathways, including AKT and hypoxia­inducible factor­1α, were also inhibited by G10 treatment and, subsequently, the downstream molecules of these pathways, such as p21, MMP2 and vascular endothelial growth factor, were also downregulated, highlighting a possible mechanism through which G10 suppresses tumor cell migration, invasion and proliferation. Importantly, in mouse NSCLC xenografts, combined treatment with G10 and paclitaxel resulted in pronounced inhibition of tumor growth. Taken together, the results of the present study highlight the potential of G10 as a novel therapeutic targeting MAOA in paclitaxel­resistant NSCLC.


Assuntos
Antineoplásicos/uso terapêutico , Carbocianinas/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Inibidores da Monoaminoxidase/uso terapêutico , Paclitaxel/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Carbocianinas/química , Carbocianinas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/efeitos dos fármacos , Reposicionamento de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Monoaminoxidase/genética , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacologia , Paclitaxel/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(12): 1320-1325, 2020 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-33328004

RESUMO

A boy, aged 2 years and 4 months, had a sudden onset of blepharoptosis of the right eyelid, accompanied by the mouth deviated to the right side, drinking cough, nystagmus, and developmental regression. Cranial MRI showed softening lesions formed after infarction of the right dorsolateral medulla oblongata, while head CT angiography showed no imaging of the proximal part of the V4 segment of the right vertebral artery. The child was diagnosed with dorsolateral medulla oblongata syndrome and was treated with gamma globulin to regulate immune function, with mannitol to reduce neuronal edema, with low-molecular-weight heparin sodium to improve local hypercoagulation of occluded blood vessels, with hyperbaric oxygen to improve local ischemia and hypoxia and promote the recovery of brain function, and with neuromuscular electrical stimulation to promote the recovery of neuromuscular function. Before discharge, only mild right ataxia and Horner syndrome remained. This article reports the first case of infantile dorsolateral medulla oblongata syndrome and provides experience for the diagnosis and treatment of the disease.


Assuntos
Blefaroptose/etiologia , Disartria/etiologia , Síndrome Medular Lateral/diagnóstico , Bulbo/diagnóstico por imagem , Pré-Escolar , Humanos , Síndrome Medular Lateral/complicações , Imageamento por Ressonância Magnética , Masculino
14.
Biomed Environ Sci ; 33(8): 566-572, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32933608

RESUMO

OBJECTIVE: This study aimed to measure the basal energy expenditure (BEE) of Chinese healthy adults and establish an accurate predictive equation for this population. METHODS: In total, 470 Chinese healthy adults had their BEE measured using the Cosmed K4b 2 portable metabolic system. Multiple linear regression analysis was applied to develop new optimal equations for predicting BEE. The bias, accuracy rate, concordance correlation coefficient (CCC), and root mean square error (RMSE) were used to evaluate the accuracy of the predictive equations. RESULTS: There was a significant difference in BEE between males and females, with 5,954 kJ/d and 5,089 kJ/d, respectively. People living in rural areas expended significantly higher BEE (5,885 kJ/d) than those in urban areas (5,279 kJ/d). Previous equations developed by Henry, Schofield, Harris-Benedict (H-B), and Liu overestimated the BEE of Chinese healthy adults. The new equations derived from the present study displayed the smallest average bias and RMSE from the measured basal energy expenditure (mBEE). The CCC of the new equations was higher than other predictive equations, but it was lower than 0.8. There was no significant difference in the accuracy rate among all predictive equations. CONCLUSIONS: Sex and regional differences in BEE were observed in Chinese healthy adults. Neither the widely used previous predictive equations nor the one derived in the present study were accurate enough for estimating the BEE of Chinese healthy adults. Further study is required to develop more accurate equations for predicting the BEE of Chinese healthy adults aged between 20-45 years.


Assuntos
Metabolismo Basal , Calorimetria/métodos , Adulto , China , Feminino , Humanos , Masculino , Adulto Jovem
15.
Pharmazie ; 75(9): 412-416, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32797765

RESUMO

Recent studies have shown that monoamine oxidase A (MAOA) is significantly expressed in malignant prostate cancer (PCa) and plays an important role in tumorigenesis indicating its potential to serve as a target for PCa treatment. Here, we choose the small molecule isoniazid as the MAOA inhibition functionality and incorporated it in the tumor-targeting moiety of heptamethine carbocyanine dyes via a pH sensitive hydrazone bond to design and synthesize novel MAOA inhibitor isoniazid-heptamethine carbocyanine dye conjugates. Cytotoxicity assay in PC-3 cells shows that all conjugates possessed improved antitumor efficacy compared with isoniazid. The tested compounds also demonstrated a moderate MAOA inhibitory effect. In conclusion, these results indicate that these conjugates exert antitumor effects by delivering the MAOA-inhibiting moiety to PCa cells.


Assuntos
Carbocianinas/química , Isoniazida/farmacologia , Inibidores da Monoaminoxidase/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Isoniazida/administração & dosagem , Isoniazida/química , Masculino , Inibidores da Monoaminoxidase/administração & dosagem , Inibidores da Monoaminoxidase/química , Neoplasias da Próstata/patologia
16.
Biomed Environ Sci ; 33(6): 414-420, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32641204

RESUMO

OBJECTIVE: To analyze the rate of erythrocyte iron incorporation and provided guidance for the iron nutrition for prepubertal children. METHODS: Fifty-seven prepubertal children of Beijing were involved in this study and each subject was orally administered 3 mg of 57Fe twice daily to obtain a total of 30 mg 57Fe after a 5-d period. The stable isotope ratios in RBCs were determined in 14th day, 28th day, 60th day, and 90th day. The erythrocyte incorporation rate in children was calculated using the stable isotope ratios, blood volume and body iron mass. RESULTS: The percentage of erythrocyte 57Fe incorporation increased starting 14 th day, reached a peak at 60 d (boys: 19.67% ± 0.56%, girls: 21.33% ± 0.59%) and then decreased. The erythrocyte incorporation rates of 57Fe obtained for girls in 60th day was significantly higher than those obtained for boys ( P < 0.0001). CONCLUSIONS: The oral administration of 57Fe to children can be used to obtain erythrocyte iron incorporation within 90 d. Prepubertal girls should begin to increase the intake of iron and further studies should pay more attention to the iron status in prepubertal children.


Assuntos
Eritrócitos/metabolismo , Isótopos de Ferro/análise , Ferro/metabolismo , Espectrometria de Massas/métodos , Pequim , Criança , Feminino , Humanos , Masculino
17.
Ying Yong Sheng Tai Xue Bao ; 31(5): 1625-1635, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32530241

RESUMO

Based on daily meteorological data and agro-meteorological data in three provinces of Northeast China during 1981-2017, combined with chilling injury indices, we analyzed the spatial-temporal distribution characteristics of solar, heat, precipitation resources and sterile-type chilling injury in rice growing season, especially in the booting and flowering stages. In 1981-2017, agriculture climatic resources in rice growing season showed a warming, drying and darkening trend. Accumulated temperature (≥10 ℃) and sunshine hours increased with a rate of 73.5 ℃·d·(10 a)-1 and 17.7 h·(10 a)-1 respectively, while precipitation decreased with a rate of 8.9 mm·(10 a)-1. At the booting stage, agricultural climatic resources showed a warming, drying and dar-kening trend. Daily average temperature increased 0.27 ℃·(10 a)-1 and sunshine hours and preci-pitation decreased 2.06 h·(10 a)-1 and 1.90 mm·(10 a)-1 respectively. At the flowering stage, agricultural climatic resources showed a trend of warming, wetting and darkening. Daily average temperature increased with a rate of 0.12 ℃·(10 a)-1, while sunshine hours decreased with a rate of 0.83 h·(10 a)-1. In contrast to that at the booting stage, precipitation in the flowering stage increased with a rate of 1.35 mm·(10 a)-1. Under the background of climate warming, the frequency and intensity of rice sterile-type chil-ling injury decreased in most regions, with significant inter-decadal fluctuations. During the study period, the frequency and intensity of sterile-type chil-ling injury were the highest in Heilongjiang Province, moderate in Jilin Province, and the lowest in Liaoning Province.


Assuntos
Oryza , Agricultura , China , Mudança Climática , Estações do Ano , Temperatura
18.
Proc Biol Sci ; 287(1926): 20200470, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32370674

RESUMO

The cuticle of ecdysozoans (Panarthropoda, Scalidophora, Nematoida) is secreted by underlying epidermal cells and renewed via ecdysis. We explore here the relationship between epidermis and external cuticular ornament in stem-group scalidophorans from the early Cambrian of China (Kuanchuanpu Formation; ca 535 Ma) that had two types of microscopic polygonal cuticular networks with either straight or microfolded boundaries. Detailed comparisons with modern scalidophorans (priapulids) indicate that these networks faithfully replicate the cell boundaries of the epidermis. This suggests that the cuticle of early scalidophorans formed through the fusion between patches of extracellular material secreted by epidermal cells, as observed in various groups of present-day ecdysozoans, including arthropods. Key genetic, biochemical and mechanical processes associated with ecdysis and cuticle formation seem to have appeared very early (at least not later than 535 Ma) in the evolution of ecdysozoans. Microfolded reticulation is likely to be a mechanical response to absorbing contraction exerted by underlying muscles. The polygonal reticulation in early and extant ecdysozoans is clearly a by-product of the epidermal cell pavement and interacted with the sedimentary environment.


Assuntos
Artrópodes , Células Epidérmicas , Animais , Evolução Biológica , China , Epiderme , Fósseis , Muda , Filogenia
19.
J Environ Manage ; 265: 110549, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32275251

RESUMO

A site experiment was conducted to assess temporal dynamics of soil organic carbon (SOC) and the drivers under no-tillage (NT) and residue retention (RR) in the North China Plain (NCP). The results indicated that NT and RR can significantly increase SOC up to a depth of 30 cm. On average, NT increased SOC by 8.1-34.5% compared with PT, and RR increased SOC by 3.5-14.4% compared with R0 at 0-10 cm. Increases in SOC under NT or RR could be increased by 4-10 percentage points through the significantly positive interactions of NT and RR. Among the sources of SOC variations, tillage-induced variations accounted for 74.4 and 44.3% of the total variations in SOC at 0-5 cm for wheat and maize season, respectively. Experimental duration was also a significant source of variation. Stepwise regression indicated dynamics in SOC at 0-5 cm mainly due to the positive effects of precipitation, the negative effects of soil bulk density for the wheat season, the negative effects of radiation for the maize season, and antagonistic effects of temperature between wheat and maize season. Generally, positive effects of NT and RR on SOC were both confirmed, but fluctuations and variations induced by interactions of practices and seasonal climatic conditions were also significant in the NCP.


Assuntos
Solo , Triticum , Agricultura , Carbono , China , Zea mays
20.
Sci Adv ; 6(9): eaay7633, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32158944

RESUMO

We present a novel concept to achieve high performance and high safety simultaneously by passivating a Li-ion cell and then self-heating before use. By adding a small amount of triallyl phosphate in conventional electrolytes, we show that resistances of the passivated cells can increase by ~5×, thereby ensuring high safety and thermal stability. High power before battery operation is delivered by self-heating to an elevated temperature such as 60°C within tens of seconds. The present approach of building a resistive cell with highly stable materials and then delivering high power on demand through rapid thermal stimulation leads to a revolutionary route to high safety when batteries are not in use and high battery performance upon operation.

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