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1.
Food Chem ; 411: 135449, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36669336

RESUMEN

The cuticle of plants, a hydrophobic membrane that covers their aerial organs, is crucial to their ability to withstand biotic and abiotic stressors. Fruit is the reproductive organ of plants, and an important dietary source that can offer a variety of nutrients for the human body, and fruit cuticle performs a crucial protective role in fruit development and postharvest quality. This review discusses the universality and diversity of the fruit cuticle composition, and systematically summarizes the metabolic process of fruit cuticle, including the biosynthesis, transport and regulatory factors (including transcription factors, phytohormones and environmental elements) of fruit cuticle. Additionally, we emphasize the postharvest functions and postharvest regulatory technologies of fruit cuticle, and propose future research directions for fruit cuticle.


Asunto(s)
Lípidos de la Membrana , Ceras , Humanos , Lípidos de la Membrana/metabolismo , Ceras/química , Frutas/química
2.
AoB Plants ; 13(3): plab008, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34194688

RESUMEN

Detecting shifts in trait values among populations of an invasive plant is important for assessing invasion risks and predicting future spread. Although a growing number of studies suggest that the dispersal propensity of invasive plants increases during range expansion, there has been relatively little attention paid to dispersal patterns along elevational gradients. In this study, we tested the differentiation of dispersal-related traits in an invasive plant, Galinsoga quadriradiata, across populations at different elevations in the Qinling and Bashan Mountains in central China. Seed mass-area ratio (MAR), an important seed dispersal-related trait, of 45 populations from along an elevational gradient was measured, and genetic variation of 23 populations was quantified using inter-simple sequence repeat (ISSR) markers. Individuals from four populations were then planted in a greenhouse to compare their performance under shared conditions. Changing patterns of seed dispersal-related traits and populations genetic diversity along elevation were tested using linear regression. Mass-area ratio of G. quadriradiata increased, while genetic diversity decreased with elevation in the field survey. In the greenhouse, populations of G. quadriradiata sourced from different elevations showed a difference response of MAR. These results suggest that although rapid evolution may contribute to the range expansion of G. quadriradiata in mountain ranges, dispersal-related traits will also likely be affected by phenotypic plasticity. This challenges the common argument that dispersal ability of invasive plants increases along dispersal routes. Furthermore, our results suggest that high-altitude populations would be more effective at seed dispersal once they continue to expand their range downslope on the other side. Our experiment provides novel evidence that the spread of these high-altitude populations may be more likely than previously theorized and that they should thus be cautiously monitored.

3.
Mycorrhiza ; 31(2): 161-171, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33559745

RESUMEN

Arbuscular mycorrhizal fungi (AMF) are suggested to be important for invasions by many exotic plants. However, it is not yet known how associations between AMF and invasive plant populations change in mountains ranges and how changed associations affect further expansion of different populations in new habitats. We conducted a field survey to detect AMF colonization rate of the invasive Galinsoga quadriradiata along an elevational gradient ranging from 223 to 1947 masl in the Qinling and Bashan Mountains, China. Additionally, a greenhouse experiment was conducted to compare plant growth performance among five elevational populations. In the field, total plant mass and seed production, as well as root AMF colonization rate, significantly decreased with elevation. When populations were grown in a novel soil environment in the greenhouse, the high-altitude populations achieved higher seed and total mass at lower AMF colonization rate than the low-altitude populations. Moreover, high AMF association was related to high intraspecific competition within low-altitude populations and limited seed production. Our results revealed that the associations between AMF and G. quadriradiata decrease with altitude in mountain ranges, and this may indicate that differentiation of association between AMF and elevational populations occurs during range expansion of G. quadriradiata. The results of the greenhouse experiment suggest that the high-altitude populations are more aggressive than the low-altitude populations in a non-stressful environment.


Asunto(s)
Micorrizas , Altitud , China , Raíces de Plantas , Plantas
4.
Am J Emerg Med ; 38(1): 73-78, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31005392

RESUMEN

OBJECTIVES: This study was designed to investigate whether an audiovisual feedback (AVF) device is beneficial for quality retention of chest compression (CC) after repetitive practices (RP). METHODS: After completion of a 45-min CC-only cardiopulmonary resuscitation (CPR) training, participants performed 3 sessions of practices on days 1, 3, and 7 under the guidance of an instructor with (RP + AVF) or without (RP) the AVF device. CC quality was determined after each session and was retested at 3 and 12 months. RESULTS: In total, ninety-seven third year university students participated in this study. CC quality was improved after 3 sessions in both the RP and RP + AVF groups. Retests at 3 months showed that the proportions of appropriate CC rate and correct hand position were significantly decreased in the RP group as compared with the last practice (p < 0.05). However, no significant changes in CC quality were observed in the RP + AVF group. However, the proportions of appropriate CC rate, depth, and complete recoil were significantly decreased after 12 months in both RP and RP + AVF groups (p < 0.05). There were no significant differences in these parameters between the RP and the RP + AVF groups at 12 months after RP. CONCLUSION: With RP, the use of an AVF device further improves initial CC skill acquisition and short-term quality retention. However, long-term quality retention is not statistically different between rescuers who receive verbal human feedback only and those who receive additional AVF device feedback after RP.


Asunto(s)
Recursos Audiovisuales , Reanimación Cardiopulmonar/educación , Competencia Clínica , Retroalimentación , Paro Cardíaco Extrahospitalario/terapia , Práctica Psicológica , Adulto , Femenino , Humanos , Masculino , Maniquíes , Retención en Psicología , Factores de Tiempo
5.
Ann Allergy Asthma Immunol ; 112(6): 539-544.e1, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24698534

RESUMEN

BACKGROUND: Upper airway edema (UAE) occurs infrequently in hereditary angioedema (HAE), but still results in significant morbidity and mortality. OBJECTIVE: To assess patients with HAE and UAE to determine whether unique features exist that can predict the risk of UAE. METHODS: Clinical, laboratory, and genetic data were compared between 43 patients with HAE and 743 UAE attacks and those without UAE and normal controls after ethics committee approval. RESULTS: Most patients had their first episode of UAE in the second (25.6%), third (27.9%), and fourth (23.3%) decades of life, and the mean age at onset was 27.3 years. Evolution of UAE from initial to maximum symptoms was 4.6 hours on average, and most cases (69.8%) progressed within 4 hours. Dyspnea was the most frequent manifestation in per-episode (92.2%) and per-patient (97.7%) analyses. Men developed more asphyxiation attacks (19 vs 2) and underwent more tracheotomies (12 vs 2) than did women. UAE was associated with facial edema in half the studied patients. Patients with a positive family history of UAE had a high risk of UAE attacks. CONCLUSION: Symptoms limited to the upper airway should be taken seriously. Dyspnea may be the only manifestation of UAE. UAE attacks most commonly start spontaneously and usually progress rapidly, as quickly as 30 minutes, from awareness of symptoms to maximum airway involvement. Patients with a positive UAE family history are predisposed to UAE attacks, and men appear to be more apt to develop asphyxiation than women.


Asunto(s)
Angioedemas Hereditarios/etiología , Asfixia/complicaciones , Disnea/complicaciones , Edema Laríngeo/complicaciones , Edema Pulmonar/complicaciones , Adolescente , Adulto , Edad de Inicio , Obstrucción de las Vías Aéreas/complicaciones , Angioedemas Hereditarios/genética , Angioedemas Hereditarios/mortalidad , Niño , Proteínas Inactivadoras del Complemento 1/genética , Proteínas Inactivadoras del Complemento 1/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 29(5): 421-5, 2008 May.
Artículo en Chino | MEDLINE | ID: mdl-18956670

RESUMEN

OBJECTIVE: To understand the knowledge and attitudes towards second hand smoking (SHS) among restaurant or bar patronage in five cities in China. METHODS: 405 restaurants and bars were conveniently selected in 5 cities as Beijing, Wuhan, Xi'an, Kunming and Guiyang. From each of these hospitality venues, at least 3 patrons, including one smoker, one female non-smoker and one male nonsmoker were asked to answer a questionnaire on their knowledge and attitudes towards SHS and smoking policies in public places. RESULTS: 43.1% of the respondents had good knowledge on SHS hazards. 65% reported that those who smoked around them had never asked for their permission, and about 60% admitted that they had never asked others to stop smoking in front of them. There were almost two thirds of patrons reporting that they once felt discomfort of SHS in restaurants or bars, nearly half of whom chose to leave the venue to avoid exposure to SHS. Though majority of patrons supported '100% smoke-free hospitals, schools and public vehicles' initiations, the proportions of patrons that supporting '100% smoke-free restaurants and bars' initiations were only 30.0% and 19.8%, respectively. In Beijing, logistic regression model analyses showed that those who supporting 100% smoke-free restaurants and bars tended to be non-smokers, aged 25 years or older and to have had at least college education. Also in Beijing, those being female, having at least college education or non-smokers were more likely to choose restaurants and bars with smoking restrictions. CONCLUSION: Though knowledge on SHS hospitality patronage was still not high or popular for the public to refuse SHS exposure, banning smoking in hospitality venues was public's inclination and would become a trend in public health endeavor.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Contaminación por Humo de Tabaco/estadística & datos numéricos , Adulto , China/epidemiología , Ciudades , Femenino , Humanos , Masculino , Persona de Mediana Edad , Restaurantes
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 28(8): 738-41, 2007 Aug.
Artículo en Chino | MEDLINE | ID: mdl-18080555

RESUMEN

OBJECTIVE: To investigate the current smoking regulations and their impacts on the environmental tobacco smoke (ETS) levels inside restaurants and bars in Beijing. METHODS: Telephone survey was used to investigate the smoking regulations. TSI Sidepak AM510 was used to measure the level of fine particles less than 2.5 microns in diameter (PM2.5) in restaurants and bars. Analysis of variance and non-parametric rank tests were used to examine the association between indoor and outdoor PM2.5 levels and (1) smoking regulations; and (2) types of restaurants and bars. RESULTS: Of the 305 restaurants and bars surveyed, 27.9% had complete or partial smoking prohibiting rules. The average indoor PM2.5, level of the 92 restaurants and bars was 253.08 microg/m3 , 102.37% higher than the outdoor level. The average indoor and outdoor PM2.5 levels in the restaurants and bars with smoking ban regulations were 93.10 microg/m3 and 110.33 microg/m3 whole 289.34 microg/m3 and 128.40 microg/m3 in those without, respectively. The average indoor and outdoor PM2.5 levels of bars were 413.46 microg/m3 and 190.62 microg/m3, respectively, while in the western fast-food restaurants, they were 83.86 microg/m3 and 104.77 microg/m3, respectively. The outdoor PM2.5 levels were higher than the indoor levels in different classes of restaurants and bars. Furthermore, there was a significant positive correlation between PM2.5 levels and the number of smokers per cube meters (r = 0.47, P < 0.001). CONCLUSION: Smoking regulations could effectively reduce the ETS level in restaurants and bars.


Asunto(s)
Contaminación del Aire Interior/análisis , Restaurantes , Fumar/legislación & jurisprudencia , Contaminación por Humo de Tabaco/análisis , Contaminación del Aire Interior/legislación & jurisprudencia , China , Monitoreo del Ambiente , Material Particulado/análisis , Contaminación por Humo de Tabaco/legislación & jurisprudencia
8.
Am J Phys Anthropol ; 122(2): 171-83, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12949837

RESUMEN

This study describes the hemoglobin concentration ([Hb]) and hematocrit (HCT) of over 1,000 Tibetan and Han children, adolescents, and young adults who were born and raised at 3,200 m, 3,800 m, or 4,300 m in Qinghai Province, western China. At 3,200 m, no altitude effect is evident in the hematological characteristics of either group. At 3,800 m and 4,300 m, both groups show [Hb] and HCT values that are above low-altitude norms. At both altitudes, Tibetan and Han children show no differences in the pattern of hematological response up to age 13. Among adolescents and young adults, however, the [Hb] and HCT of Han males and females are elevated compared to Tibetans. This indicates that the adolescent period may involve a divergence in the responses to hypoxia made by some individuals in these two groups. Also, many other adolescents and young adults in both groups show similar hematological characteristics, indicating that many Tibetans and Han share similar hematological responses to hypoxia.


Asunto(s)
Adaptación Fisiológica , Altitud , Pueblo Asiatico , Hematócrito , Hemoglobinas/análisis , Adolescente , Adulto , Niño , China/epidemiología , Femenino , Humanos , Masculino , Tibet/etnología
9.
Am J Hum Biol ; 14(4): 494-510, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12112571

RESUMEN

Forced vital capacity (FVC), forced expiratory volume at 1 second (FEV(1)), and FEV(1)/FVC ratios were determined for 531 individuals of Han Chinese descent living at low altitude (250 m) near Beijing and for 592 individuals of Han descent who were born and raised at three high altitudes (3,200 m, 3,800 m, 4,300 m) in Qinghai Province, P.R.C. The study included males and females, ages 6-51 years. Thorax widths, depths, and circumferences of Han females and males born and raised at high altitude are similar to those of low-altitude Han. On the other hand, high-altitude children and adolescents have larger relative sitting heights, indicating greater thorax lengths. After adjusting for this variation in morphology, mean FVC values among 6-21 year-old Han at high altitude are only between 136 mL (for females) and 173 ml (for males) greater than those determined at low altitude but the differences are statistically significant and are maintained consistently throughout the growth period. These data indicate that growth at high altitude produces small-to-moderate increases in lung volumes (about 6%) relative to genetically similar groups growing up at low altitude. In addition, there is no evidence that lung volume growth is accelerated relative to morphological growth among Han children born and raised at high altitude. Adults, 22-51 years, also show greater FVC values at high altitude but the size of the increase relative to Han at low altitude is variable (3% in males and 11% in females). Greater lung function at high altitude is unlikely to result from increased activity or lower pollution, and thus appears to be primarily a result of development in a hypoxic environment. Differences in FVC and FEV(1) at 3,200 m, 3,800 m, and 4,300 m are generally not significant, so that living at altitudes between 3,200 m and 4,300 m appears to have little additional effect on volumetric growth.


Asunto(s)
Altitud , Volumen Espiratorio Forzado , Capacidad Vital , Adolescente/fisiología , Adulto , Antropometría , Niño , China , Femenino , Humanos , Hipoxia/fisiopatología , Pulmón/fisiología , Masculino , Persona de Mediana Edad/fisiología
10.
Am J Hum Biol ; 12(5): 665-681, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11534060

RESUMEN

This study compares the morphological characteristics of Han children, adolescents, and young adults who were born at 250 m near Beijing and at three high altitudes in Qinghai Province, Peoples Republic of China (3,200 m, 3,800 m, and 4,300 m). From ages 6 through 15, Han children growing up at high altitudes are significantly shorter, lighter, have less fat, and are less muscular than Han children growing up at low altitude. However, older adolescents and young adults show no such altitude differences. Younger adolescents and children in this study were all born after the government economic reforms of 1978. These reforms had a greater impact on the growth of children in and around large cities than on those in more remote areas. Therefore, the altitude differences in size among Han children ages 15 and younger may be a consequence of regional variation in health and nutrition, rather than due to the influence of hypoxia. There are no altitude-related differences in thorax dimensions among Han children, adolescents, or young adults. This suggests that hypoxia does not affect the thorax growth of Han children. Am. J. Hum. Biol. 12:665-681, 2000. Copyright 2000 Wiley-Liss, Inc.

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