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1.
Front Plant Sci ; 15: 1321950, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38292912

RESUMEN

Introduction: Invasive species have been identified as a major threat to native biodiversity and ecosystem functioning worldwide due to their superiority in spread and growth. Such superiority is explained by the invasional meltdown phenomena, which suggests that invasive species facilitate the establishment of more invasive species rather than native species by modifying the plant-soil feedback (PSF). Methods: We conducted a two-phase plant-soil feedback experiment using the native Prosopis cineraria and the invasive Prosopis juliflora in Oman. Firstly, we conditioned the soil by planting seedlings of native species, invasive species, native and invasive species "mixed", and unconditioned soil served as a control. Secondly, we tested the feedback of these four conditioned soil on the two species separately by measuring the productivity (total biomass) and the performance in the form of plant functional traits (plant height, specific leaf area (SLA), leaf nitrogen content (Nmass), leaf carbon content (Cmass) and specific root length (SRL) of native and invasive species as well as the nutrient availability in soil (soil organic carbon (SOC) and soil total nitrogen (STN)). Results and discussion: We found that the native species produced more biomass, best performance, and higher SOC and STN when grown in soil conditioned by native species, additionally, it gave lower biomass, reduced performance, and lower SOC and STN when grown in the soil conditioned by invasive and mixed species. These results suggest negative PSF for native species and positive PSF for invasive species in the soil conditioned by invasive species, which can be considered as red flag concerning the restoration of P. cineraria as an important native species in Oman, as such positive PSF of the invasive species P. juliflora will inhibit the regeneration of P. cineraria.

2.
Plants (Basel) ; 12(11)2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37299089

RESUMEN

Heavy metal stress, including from chromium, has detrimental effects on crop growth and yields worldwide. Plant growth-promoting rhizobacteria (PGPR) have demonstrated great efficiency in mitigating these adverse effects. The present study investigated the potential of the PGPR strain Azospirillum brasilense EMCC1454 as a useful bio-inoculant for boosting the growth, performance and chromium stress tolerance of chickpea (Cicer arietinum L.) plants exposed to varying levels of chromium stress (0, 130 and 260 µM K2Cr2O7). The results revealed that A. brasilense EMCC1454 could tolerate chromium stress up to 260 µM and exhibited various plant growth-promoting (PGP) activities, including nitrogen fixation, phosphate solubilization, and generation of siderophore, trehalose, exopolysaccharide, ACC deaminase, indole acetic acid, and hydrolytic enzymes. Chromium stress doses induced the formation of PGP substances and antioxidants in A. brasilense EMCC1454. In addition, plant growth experiments showed that chromium stress significantly inhibited the growth, minerals acquisition, leaf relative water content, biosynthesis of photosynthetic pigments, gas exchange traits, and levels of phenolics and flavonoids of chickpea plants. Contrarily, it increased the concentrations of proline, glycine betaine, soluble sugars, proteins, oxidative stress markers, and enzymatic (CAT, APX, SOD, and POD) and non-enzymatic (ascorbic acid and glutathione) antioxidants in plants. On the other hand, A. brasilense EMCC1454 application alleviated oxidative stress markers and significantly boosted the growth traits, gas exchange characteristics, nutrient acquisition, osmolyte formation, and enzymatic and non-enzymatic antioxidants in chromium-stressed plants. Moreover, this bacterial inoculation upregulated the expression of genes related to stress tolerance (CAT, SOD, APX, CHS, DREB2A, CHI, and PAL). Overall, the current study demonstrated the effectiveness of A. brasilense EMCC1454 in enhancing plant growth and mitigating chromium toxicity impacts on chickpea plants grown under chromium stress circumstances by modulating the antioxidant machinery, photosynthesis, osmolyte production, and stress-related gene expression.

3.
Ecol Evol ; 12(9): e9296, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36177142

RESUMEN

Ecosystem functions are heavily dependent on the functional composition of the plant community, i.e., the functional traits of plants forming the community. This, on the one hand, depends on plant occurrence, but on the other hand, depends on the intraspecific variability of functional traits of the species, which are influenced by climate and nutrient availability and affected by plant-plant interactions. To illustrate that, we studied the effects of drought and nitrogen addition (+ N), two important abiotic variables which are changing with ongoing global change, as well as their combined effect on the functional responses of grassland communities in semi-arid environments of Northern Africa comprising of natural and invasive species. We conducted an experiment where we planted three native species and one invasive plant species in artificial communities of five individuals per species per plot. We exposed these communities to four different treatments: a drought treatment, an N-addition treatment, the combination between drought and N-addition, as well as a control. To assess the performance of plants within treatments, we measured selected plant functional traits (plant height, specific leaf area [SLA], leaf dry matter content [LDMC], N content of the leaves [Nmass], specific root length [SRL], and root diameter) for all individuals occurring in our plots, and additionally assessed the above and belowground biomass for each plant individual. We found that the invasive species showed a higher performance (higher biomass accumulation, taller plants, higher SLA, Nmass, SRL, and root diameter as well as lower LDMC) than the native species under drought conditions. The invasive species was especially successful with the combined impact of drought + N, which is a likely scenario in ongoing global change for our research area. Thus, plant functional traits might be a key factor for the invasion success of plant species which will be even more pronounced under ongoing global change.

4.
Plants (Basel) ; 10(11)2021 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-34834774

RESUMEN

Land-use changes have huge impacts on natural vegetation, especially megaprojects, as the vegetation layer is destroyed in the course of construction works affecting the plant community composition and functionality. This large-scale disturbance might be a gateway for the establishment of invasive plant species, which can outcompete the natural flora. In contrast, species occurring in the area before the construction are not able to re-establish. In this study, we analyzed the impact of a pipeline construction on a wetland nature reserve located in northern Egypt. Therefore, we analyzed the plant species occurrence and abundance and measured each plant species' traits before the construction in 2017 as well as on multiple occasions up to 2 years after the construction had finished on altogether five sampling events. We found that the construction activity led to the establishment of an invasive species which previously did not occur in the area, namely, Imperata cylindrica, whereas five species (Ipomoea carnea, Pluchea dioscoridis, Polygonum equisetiforme, Tamarix nilotica, and Typha domingensis) could not re-establish after the disturbance. The functionality of ecosystems assessed via the analysis of plant functional traits (plant height, specific leaf area, and leaf dry matter content) changed within species over all sampling events and within the community showing a tendency to approximate pre-construction values. Functional dispersion and Rao's quadratic diversity were higher after the megaproject than before. These findings are important to capture possible re-establishment and recovery of natural vegetation after construction and raise awareness to the impact of megaprojects, especially in areas which are high priority for conservation.

5.
Fertil Steril ; 115(3): 793-801, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33461754

RESUMEN

OBJECTIVE: To evaluate the efficacy of carbetocin versus placebo in decreasing intraoperative blood loss and the need for blood transfusion during abdominal myomectomy. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: Tertiary university hospital from September 2019 to February 2020. PATIENT(S): A total of 138 women with symptomatic leiomyoma who were candidates for abdominal myomectomy (n = 69 in each group). INTERVENTION(S): We randomized the study participants in a 1:1 ratio to carbetocin and placebo groups. Intravenous 100 µg carbetocin or placebo was administered slowly after induction of anesthesia. MAIN OUTCOME MEASURE(S): Intraoperative blood loss, need for blood transfusion, postoperative hemoglobin, operative time, length of hospitalization, and drug side-effects. RESULT(S): The baseline characteristics were similar among all groups. Carbetocin had significantly lower intraoperative blood loss compared with placebo (mean difference 184 mL). Hemoglobin level 24 hours after surgery was significantly lower in the placebo group than in the carbetocin group (9.1 ± 0.8 vs. 10.3 ± 0.6 g/dL). Eight women in the carbetocin group needed blood transfusion compared with 17 in placebo group. Operative time, length of hospitalization, and side-effects were similar in both groups. CONCLUSION(S): A single preoperative intravenous dose of 100 µg carbetocin is a simple, practical, and effective method of decreasing intraoperative blood loss and the need for blood transfusion during abdominal myomectomy, with tolerable, few, nonsignificant side-effects. CLINICAL TRIAL REGISTRATION NUMBER: NCT04083625.


Asunto(s)
Pérdida de Sangre Quirúrgica/prevención & control , Leiomioma/cirugía , Oxitócicos/administración & dosificación , Oxitocina/análogos & derivados , Miomectomía Uterina/efectos adversos , Neoplasias Uterinas/cirugía , Adulto , Preparaciones de Acción Retardada/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Leiomioma/tratamiento farmacológico , Persona de Mediana Edad , Oxitocina/administración & dosificación , Estudios Prospectivos , Resultado del Tratamiento , Miomectomía Uterina/tendencias , Neoplasias Uterinas/tratamiento farmacológico
6.
Data Brief ; 32: 106289, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32984479

RESUMEN

Thermo-optical properties of construction materials are important factors while designing a building. Human comfort and environmental issues are the main reasons inciting researchers to work in this field. For instance, the thermal conductivity coefficient, the optical reflectance, the optical transmittance and the optical absorbance of materials are frequently measured properties in civil engineering. Currently, each of these physical coefficients is measured separately by various devices. A new experimental device is therefore designed to measure these properties in a single unit. The data presented in the article consists of the experimentation process of designing a new type device. This paper includes data for calibration, measurements and validation for the elements of the new device. This data has been collected in the laboratory and is made available for reproducibility and improvement research in the field of thermo-optical properties of construction materials. This data article is related to the original research article of Fakra et al. denoted "A new simple experimental device for measuring the thermo-optical properties of translucent construction materials." [1].

7.
Glob Chang Biol ; 26(1): 119-188, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31891233

RESUMEN

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.


Asunto(s)
Acceso a la Información , Ecosistema , Biodiversidad , Ecología , Plantas
8.
J Matern Fetal Neonatal Med ; 33(10): 1631-1637, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-30345864

RESUMEN

Background: Severe intrauterine growth restriction complicates approximately 0.4% of the pregnancies. It increases the risk of perinatal morbidity and mortality.Subjects and methods: A double blind placebo controlled trial was conducted in Beni Suef University hospitals during 2017. It included 46 pregnant women with severe intrauterine growth restriction. Women were randomly allocated into two groups each included 23 patients. Intervention group received sildenafil citrate 20 mg orally three times a day, in addition to fish oil and zinc supplementation. Control group received tablets similar to sildenafil and the same treatment as intervention group. Primary outcomes included improvement in umbilical and middle cerebral arteries pulsatility indices and abdominal circumference.Results: Umbilical and middle cerebral arteries Doppler indices showed significant difference between groups after intake of sildenafil. Umbilical artery pulsatility index decreased significantly (p value = .001) while middle cerebral artery pulsatility index increased significantly in intervention group (p value0.001). Moreover, abdominal circumference growth velocity improved after two weeks of sildenafil intake (p value = .001).Conclusions: Sildenafil citrate may improve uteroplacental and fetal cerebral perfusion in pregnancies complicated by severe intrauterine growth restriction. It also improves abdominal circumference growth velocity. A wide scale randomized trials are needed for evaluation of neonatal and long term morbidity and mortality outcomes of pregnancies treated by sildenafil citrate.


Asunto(s)
Retardo del Crecimiento Fetal/tratamiento farmacológico , Citrato de Sildenafil/administración & dosificación , Vasodilatadores/administración & dosificación , Administración Oral , Adulto , Peso al Nacer , Método Doble Ciego , Egipto , Femenino , Aceites de Pescado/uso terapéutico , Humanos , Recién Nacido , Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/efectos de los fármacos , Placenta/irrigación sanguínea , Placenta/efectos de los fármacos , Embarazo , Flujo Pulsátil , Citrato de Sildenafil/efectos adversos , Ultrasonografía Prenatal , Arterias Umbilicales/diagnóstico por imagen , Arterias Umbilicales/efectos de los fármacos , Vasodilatadores/efectos adversos , Zinc/administración & dosificación
9.
Pregnancy Hypertens ; 18: 173-178, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31678758

RESUMEN

INTRODUCTION: Preeclampsia is strongly associated with placental hypoperfusion. Genetic factors have an impact on the pathogenesis of preeclampsia. The aim is to assess the association of Vascular Endothelial Growth Factor (C2578A) gene polymorphism with the occurrence and severity of preeclampsia and the umbilical artery Doppler changes among preeclamptic women. MATERIALS AND METHODS: This case-control study was conducted in clinical and Chemical pathology and Obstetrics departments in Beni- Suef University, Egypt. Two hundred and ninety pregnant women above 20 weeks gestational age until delivery were divided into 2 main groups. The patient group included 145 preeclamptic women who were further sub grouped according to the severity of preeclampsia into 82 severe and 63 mild cases. Control group included 145 normotensive pregnant women. Our primary outcome was detection of VEGF C 2578 A gene mutations by a polymerase chain reaction. A secondary outcome was Doppler changes in the pulsatility index of the umbilical artery compared with VEGF genotypes. RESULTS: Our study showed that VEGF C 2578 A genotype and alleles frequencies were not related to the occurrence of preeclampsia (p-value 0.513 and 0.549, respectively), odds ratio (95%CI) 1.154 (0.724-1.848). Mild preeclamptic cases showed no significance comparing VEGF genotypes studied and pulsatility index of the umbilical artery. However, severe cases showed p-value < 0.0001. CONCLUSION: We concluded that VEGF 2578C/A polymorphism had no association with the occurrence of preeclampsia in studied groups, whereas there was a significant relationship among severe cases between CA and CC genotypes and pulsatility index of the umbilical artery.


Asunto(s)
Predisposición Genética a la Enfermedad , Preeclampsia/genética , Arterias Umbilicales/fisiopatología , Adolescente , Adulto , Velocidad del Flujo Sanguíneo , Estudios de Casos y Controles , Egipto , Femenino , Humanos , Polimorfismo Genético , Preeclampsia/fisiopatología , Embarazo , Flujo Pulsátil , Índice de Severidad de la Enfermedad , Ultrasonografía Doppler , Arterias Umbilicales/diagnóstico por imagen , Factor A de Crecimiento Endotelial Vascular , Factor C de Crecimiento Endotelial Vascular , Población Blanca , Adulto Joven
10.
J Biosoc Sci ; 51(2): 273-281, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-29747707

RESUMEN

Two administrations of the Coloured Progressive Matrices in Egypt were compared. The first was administered to a large, representative national sample between 2011 and 2013. The second was administered to primary school pupils in villages in Menoufia in northern Egypt in 2017. Adjusting for the Flynn Effect, the IQ of the rural northern Egyptians was shown to be statistically significantly higher than the national average. It is demonstrated that this is consistent with regional socioeconomic differences in Egypt, which strongly imply that northern Egypt has a higher average IQ than southern Egypt.


Asunto(s)
Inteligencia , Población Rural/estadística & datos numéricos , Medio Social , Factores Socioeconómicos , Población Urbana/estadística & datos numéricos , Niño , Preescolar , Egipto , Femenino , Humanos , Pruebas de Inteligencia/estadística & datos numéricos , Masculino , Psicometría , Instituciones Académicas/estadística & datos numéricos
11.
J Pediatr Adolesc Gynecol ; 31(6): 571-574, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30064003

RESUMEN

STUDY OBJECTIVE: Female circumcision (FC) is a deeply rooted practice in Egypt with deblitating physical and psychological consequences. During the past 2 decades there have been sincere efforts to reduce this practice. The objective of this study was to investigate the prevalence of circumcision. DESIGN: Cross-sectional study. SETTING: Beni-Suef City, Egypt. PARTICIPANTS: Young women (12-25 years of age). INTERVENTIONS: A survey was given to 3353 young women residing in Beni-Suef City. Data were collected using a questionnaire that included information about the sociodemographic characteristics of participants, their gynecological data, exposure to FC, and complaints associated with menses during the previous year. MAIN OUTCOME MEASURES: Prevalence of FC in rural areas in Beni Suef. RESULTS: Of the 3353 interviewed women, 1846 (55%) were circumcised. Women residing in rural areas, married women, and those who had illiterate parents were more likely to have experienced circumcision. Students were less likely to be circumcised (P < .05). The circumcised girls reported shorter menstrual cycles and dysuria with menses (P < .05). Dysmenorrhea, generalized aching, and nervousness were the most common complaints associated with menses in both groups, with no statistically significant differences (P > .05). CONCLUSION: FC is highly prevalent in rural areas in Beni-Suef, however, compared with previous reports it seems that the rates of circumcision have decreased markedly. Despite this decrease, the practice of female genital mutilation is still highly prevalent, suggesting that future research and intervention will be needed to eliminate this practice.


Asunto(s)
Circuncisión Femenina/estadística & datos numéricos , Adolescente , Adulto , Niño , Estudios Transversales , Egipto/epidemiología , Femenino , Humanos , Trastornos de la Menstruación/epidemiología , Trastornos de la Menstruación/etiología , Prevalencia , Estudiantes/estadística & datos numéricos , Encuestas y Cuestionarios , Adulto Joven
12.
Int J Gynaecol Obstet ; 143(2): 150-155, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30058068

RESUMEN

OBJECTIVE: To evaluate the usefulness of Doppler indices of the corpus luteum and uterine artery in combination with serum progesterone and cancer antigen 125 (CA125) as prognostic tools in first-trimester threatened spontaneous abortion. METHODS: Pregnant women with threatened spontaneous abortion at a pregnancy duration 8-10 weeks were enrolled into an observational prospective clinical trial at a university hospital in Egypt during 2015. Doppler indices (uterine artery/corpus luteum resistance index and pulsatility index) and biochemical markers (CA125, progesterone) were determined and compared by pregnancy outcome (spontaneous abortion vs continuing pregnancy at 20 weeks). RESULTS: Of 100 women included, 16 had a spontaneous abortion. These women had a higher CA125 value than did women without an abortion (P<0.001), whereas the progesterone level among women with an abortion was lower (P<0.001). The Doppler indices were not significantly different between the groups, but calculation of the uterine artery resistance index as a percentage of the normal standard value at a given pregnancy duration revealed significant differences (P<0.001) between the two groups. CONCLUSION: Serum progesterone and CA125 are useful provisional predictors of spontaneous abortion, whereas the Doppler indices are not. The two biomarkers could be used as a basis to counsel anxious couples. CLINICALTRIALS.GOV: NCT02420769.


Asunto(s)
Aborto Espontáneo , Amenaza de Aborto , Aborto Espontáneo/sangre , Aborto Espontáneo/diagnóstico por imagen , Amenaza de Aborto/sangre , Amenaza de Aborto/diagnóstico por imagen , Adulto , Biomarcadores/sangre , Antígeno Ca-125/sangre , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Resultado del Embarazo , Primer Trimestre del Embarazo , Progesterona/sangre , Estudios Prospectivos , Valores de Referencia , Ultrasonografía Doppler , Arteria Uterina/diagnóstico por imagen
13.
J Environ Manage ; 169: 202-9, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26760443

RESUMEN

Soil erosion is a widespread problem in agricultural landscapes, particularly in regions with strong rainfall events. Vegetated field margins can mitigate negative impacts of soil erosion off-site by trapping eroded material. Here we analyse how local management affects the trapping capacity of field margins in a monsoon region of South Korea, contrasting intensively and extensively managed field margins on both steep and shallow slopes. Prior to the beginning of monsoon season, we equipped a total of 12 sites representing three replicates for each of four different types of field margins ("intensive managed flat", "intensive managed steep", "extensive managed flat" and "extensive managed steep") with Astroturf mats. The mats (n = 15/site) were placed before, within and after the field margin. Sediment was collected after each rain event until the end of the monsoon season. The effect of management and slope on sediment trapping was analysed using linear mixed effects models, using as response variable either the sediment collected within the field margin or the difference in sediment collected after and before the field margin. There was no difference in the amount of sediment reaching the different field margin types. In contrast, extensively managed field margins showed a large reduction in collected sediment before and after the field margins. This effect was pronounced in steep field margins, and increased with the size of rainfall events. We conclude that a field margin management promoting a dense vegetation cover is a key to mitigating negative off-site effects of soil erosion in monsoon regions, particularly in field margins with steep slopes.


Asunto(s)
Agricultura/métodos , Ambiente , Suelo , Modelos Teóricos , Lluvia , República de Corea , Estaciones del Año
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