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1.
Anim Sci J ; 94(1): e13823, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36922402

RESUMO

Near-infrared (NIR) spectroscopy was employed to determine the differences between forage mixtures of winter cereals and Italian ryegrass and to evaluate fermentation characteristics of mixed silages. Forages were harvested on five phases (Cuts 1-5), with 1 week interval (n = 100). The yield of the last harvest (Cut 5) was ensiled and analyzed on four different days (D0, D7, D14, and D90) (n = 80). Principal component analysis based on the NIR data revealed differences according to the days of harvest, differences between winter cereals and Italian ryegrass forages, and differences in the fermentation stages of silages. The partial least square regression models for crude protein (CP), crude fiber (CF), and ash gave excellent determination coefficient in cross-validation (R2 CV > 0.9), while models for ether extract (EE) and total sugar content were weaker (R2 CV = 0.87 and 0.74, respectively). The values of root mean square error of cross-validation were 0.59, 0.76, 0.22, 0.31, and 2.36 %DM, for CP, CF, EE, ash, and total sugar, respectively. NIR proved to be an efficient tool in evaluating type and growth differences of the winter cereals and Italian ryegrass forage mixtures and the quality changes that occur during ensiling.


Assuntos
Lolium , Animais , Grão Comestível/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Espectroscopia de Luz Próxima ao Infravermelho/veterinária , Silagem/análise , Carboidratos da Dieta/metabolismo , Proteínas/metabolismo , Itália , Açúcares
2.
Plants (Basel) ; 11(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35270110

RESUMO

High temperature induces oxidative processes in wheat, the alleviation of which is promising using biostimulants. Priming has been used for enhancing stress tolerance of seedlings. However, the usage of biostimulants for priming is an unexplored area under either normal or stress conditions. Therefore, the aim of our study was to evaluate the heat stress alleviation capability of differentially applied biostimulant treatments on wheat seedlings. The investigation included stress parameters (fresh/dry weight ratio, chlorophyll content estimation, antioxidant capacity and lipid oxidation) combined with biophoton emission measurement, since with this latter non-invasive technique, it is possible to measure and elucidate in vivo stress conditions in real-time using lipid oxidation-related photon emissions. We confirmed that a single biostimulant pretreatment increased antioxidant capacity and decreased biophoton release and lipid oxidation, indicating the reduction of the harmful effects of heat stress. Therefore, biophoton emission proved to be suitable for detecting and imaging the effects of heat stress on wheat seedlings for the first time. Two-way analysis of variance (ANOVA) revealed that biostimulant (p = 4.01 × 10-7) treatments, temperature (p = 9.07 × 10-8), and the interaction of the two factors (p = 2.07 × 10-5) had a significant effect on the overall count per second values of biophoton emission, predicting more efficient biostimulant utilization practices, even for seed priming purposes.

3.
Ground Water ; 60(2): 192-209, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34551128

RESUMO

Heat as a tracer in fractured porous aquifers is more sensitive to fracture-matrix processes than a solute tracer. Temperature evolution as a function of time can be used to differentiate fracture and matrix characteristics. Experimental hot (50 °C) and cold (10 °C) water injections were performed in a weathered and fractured granite aquifer where the natural background temperature is 30 °C. The tailing of the hot and cold breakthrough curves, observed under different hydraulic conditions, was characterized in a log-log plot of time vs. normalized temperature difference, also converted to a residence time distribution (normalized). Dimensionless tail slopes close to 1.5 were observed for hot and cold breakthrough curves, compared to solute tracer tests showing slopes between 2 and 3. This stronger thermal diffusive behavior is explained by heat conduction. Using a process-based numerical model, the impact of heat conduction toward and from the porous rock matrix on groundwater heat transport was explored. Fracture aperture was adjusted depending on the actual hydraulic conditions. Water density and viscosity were considered temperature dependent. The model simulated the increase or reduction of the energy level in the fracture-matrix system and satisfactorily reproduced breakthrough curves tail slopes. This study shows the feasibility and utility of cold water tracer tests in hot fractured aquifers to boost and characterize the thermal matrix diffusion from the matrix toward the flowing groundwater in the fractures. This can be used as complementary information to solute tracer tests that are largely influenced by strong advection in the fractures.

4.
Plants (Basel) ; 10(3)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810174

RESUMO

Recent studies revealed that from various ecological factors influencing nectar yield and quality of a plant, soil properties can be as important as microclimatic features. To date, few studies have investigated the relationship of soil characters to nectar traits of bee pollinated plants growing in natural associations. Our study intended to reveal which soil properties had the most powerful impact on nectar variables of wild garlic (Allium ursinum L.). Specimens were collected from fourteen habitats in two different years, and were potted in their original soil under the same climatic conditions. Nectar volumes and sugar concentrations were measured and soil samples were analysed for fourteen parameters. Statistical analyses revealed that the number of nectar producing Allium flowers, as well as the nectar volume and sugar content of nectar in individual flowers were influenced by both year and habitat. The humus, iron and sulphate content of soil showed negative correlation with the number of flowers producing nectar; total nectar volumes were negatively correlated with humus and iron content, but positively affected by magnesium content of the soil. Our results suggest that in addition to the effect of microclimatic factors, certain soil properties can have significant impact on nectar traits.

5.
Prostate Int ; 6(2): 50-54, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29922632

RESUMO

BACKGROUND: 18-Fluoride labeled sodium fluoride (Na-18-F) positron emission tomography with computer tomography (PET/CT) has a better sensitivity and specificity than whole body bone scan (WBBS) in detecting osseous metastatic prostate cancer. We performed a pilot study of 20 men to examine what level of impact Na-18-F PET/CT has on management plans when used for staging newly diagnosed prostate cancer. MATERIALS AND METHODS: Twenty men were prospectively enrolled into the study in South Australia. Men were eligible if they had newly diagnosed, untreated, and biopsy-confirmed intermediate- or high-risk prostate cancer (D'Amico classification). WBBS and Na-18-F PET/CT scans were performed within 1 week of each other. Following review of the WBBS, treatment type and intent was documented by the treating urologist. The Na-18-F PET/CT scan was then reviewed. The impact of the Na-18-F PET/CT was measured on whether treatment modality or intent was subsequently altered: high impact = treatment intent or modality was changed; medium impact = treatment modality was modified; low impact = no change in treatment. RESULTS: In 18 men (90%), the WBBS and Na-18-F PET/CT were negative for osseous metastases. In one man (5%), the WBBS demonstrated widespread osseous metastases which were similarly demonstrated on the Na-18-F PET/CT. One man (5%) had a normal WBBS; however, the Na-18-F PET/CT demonstrated widespread osseous metastases. Subsequently, in 19 men (95%), the results of the two scans were congruent and the addition of the Na-18-F PET/CT scan demonstrated a low impact on management. In one man (5%), the addition of the Na-18-F PET/CT had a high impact as treatment type and intent was altered. CONCLUSIONS: Our pilot study is the first of its kind in Australia, and our findings suggest that Na-18-F PET/CT is a safe and feasible modality for staging prostate cancer. However, its true impact on prostate cancer management warrants further investigation.

6.
Eur J Cardiothorac Surg ; 54(4): 781-783, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29596613

RESUMO

Left ventricular assist devices (LVADs) may require subsequent pump exchange due to device thrombosis or thromboembolism. A limited left thoracotomy may offer advantages over standard full sternotomy in redo procedures by preserving pristine median access and decreasing the potential for re-entry injuries, postoperative bleeding and transfusion requirements. We describe repeat LVAD exchange via the left limited thoracotomy with outflow graft anastomosis to the left subclavian artery with the correction of LVAD inflow cannula angulation following recurrent LVAD thromboses.


Assuntos
Hemorragia Cerebral/etiologia , Remoção de Dispositivo/métodos , Cardiopatias/etiologia , Coração Auxiliar/efeitos adversos , Complicações Pós-Operatórias , Trombose/etiologia , Falha de Equipamento , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Reoperação , Estudos Retrospectivos
7.
Int Urol Nephrol ; 50(1): 13-19, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29188489

RESUMO

INTRODUCTION: Multiparametric MRI (mpMRI) is useful in detecting anterior prostate tumours. Due to the location of anterior tumours, they are often diagnosed with a large size and may be suspicious for extra-prostatic extension (EPE). We aim to evaluate whether PI-RADS v2 is more accurate in assessing anterior prostate lesions identified on mpMRI compared to PI-RADS v1. METHODS: Patients with anterior prostate lesions diagnosed on mpMRI who proceeded to a cognitive fusion transperineal prostate biopsy were identified. Each mpMRI was blinded and read by two experienced prostate MRI radiologists and assigned a PI-RADS v1 and PI-RADS v2 score, and the presence of EPE was estimated. Correlation was made with transperineal histopathology and, where relevant, radical prostatectomy histopathology. Concordance measures between PI-RADS v1 and PI-RADS v2, and between examiners of the same PI-RADS score were calculated using a weighted kappa. RESULTS: Fifty-eight consecutive men were identified. Concordance between the examiners for PI-RADS v1 and for v2 showed substantial agreement (version 1: weighted kappa 0.71; version 2: weighted kappa 0.69). There was no difference in accuracy when using PI-RADS v1 or PI-RADS v2 to predict clinically significant cancer. There was poor correlation between EPE measured on mpMRI compared with EPE in radical prostatectomy histopathology. CONCLUSION: PI-RADS v2 is reproducible between radiologists but does not have improved accuracy for diagnosing anterior tumours of the prostate when compared to PI-RADS v1. Multiparametric MRI is accurate at detecting anterior tumours with a sensitivity of 86-88%.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Imageamento por Ressonância Magnética/normas , Guias de Prática Clínica como Assunto , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Variações Dependentes do Observador , Próstata/patologia , Prostatectomia , Neoplasias da Próstata/cirurgia , Curva ROC
9.
Aquat Sci ; 77(3): 315-324, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26321853

RESUMO

The temporal dynamic of riverine ecosystems and their fish communities and populations has been addressed in ecological theory and management for several decades. A growing number of case studies on the historic development especially of European and North American rivers have been published. Nonetheless, a theoretical debate about the contributions and limits of historical approaches and interdisciplinary co-operation is lacking. This article presents a brief overview of the role of history in river and fish ecology and suggests historical ecology as a scientific field that can offer a framework for future research. Based on case studies compiled in this special issue on the "Historical ecology of riverine fish in Europe", we draw conclusions on long-term changes of fish communities, on fisheries, aquatic ecosystem management and past habitat alterations and the potential of archaeological remains and written sources to study them. We discuss how modelling of historical fish data can help elucidate the effects of climate change and human influences on rivers and fish. Finally, we account for the necessity to consider appropriate spatial and temporal scales. In conclusion we call for future comparative studies on continental and global scales and methodological development, which can benefit especially from recent advances in marine historical ecology. We suggest that future interdisciplinary studies of ecologists, hydrologists, historians and archaeologists can reveal the history of riverine ecosystems as socio-ecological systems, addressing both their natural dynamics and human dimension. Such an endeavor can also support developing management plans for habitat restoration and conservation against the background of global change.

10.
Int J Mol Sci ; 15(12): 23766-91, 2014 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-25535074

RESUMO

During in vitro fertilization of wheat (Triticum aestivum, L.) in egg cells isolated at various developmental stages, changes in cytosolic free calcium ([Ca2+]cyt) were observed. The dynamics of [Ca2+]cyt elevation varied, reflecting the difference in the developmental stage of the eggs used. [Ca2+]cyt oscillation was exclusively observed in fertile, mature egg cells fused with the sperm cell. To determine how [Ca2+]cyt oscillation in mature egg cells is generated, egg cells were incubated in thapsigargin, which proved to be a specific inhibitor of the endoplasmic reticulum (ER) Ca2+-ATPase in wheat egg cells. In unfertilized egg cells, the addition of thapsigargin caused an abrupt transient increase in [Ca2+]cyt in the absence of extracellular Ca2+, suggesting that an influx pathway for Ca2+ is activated by thapsigargin. The [Ca2+]cyt oscillation seemed to require the filling of an intracellular calcium store for the onset of which, calcium influx through the plasma membrane appeared essential. This was demonstrated by omitting extracellular calcium from (or adding GdCl3 to) the fusion medium, which prevented [Ca2+]cyt oscillation in mature egg cells fused with the sperm. Combined, these data permit the hypothesis that the first sperm-induced transient increase in [Ca2+]cyt depletes an intracellular Ca2+ store, triggering an increase in plasma membrane Ca2+ permeability, and this enhanced Ca2+ influx results in [Ca2+]cyt oscillation.


Assuntos
Sinalização do Cálcio , Cálcio/metabolismo , Fertilização in vitro , Triticum/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Fertilização in vitro/métodos , Espaço Intracelular/metabolismo , Lactonas/farmacologia , Imagem Molecular , Sesquiterpenos/farmacologia
11.
P T ; 39(11): 759, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25395818
13.
J Dtsch Dermatol Ges ; 9(3): 212-22, 2011 Mar.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-21352483

RESUMO

BACKGROUND: Malignant melanoma (MM) is dramatically increasing in light-skinned populations worldwide. Staging and regular follow-up examinations are essential. The purpose of this study was to compare the diagnostic accuracy of whole-body MRI with the standard diagnostic algorithm (whole-body CT and brain MRI) in patients with stage III/IV MM. PATIENTS AND METHODS: A group of 50 consecutively admitted patients with stage III/IV MM were included in the study. Whole-body CT and brain MRI scans were performed. Additionally, all patients underwent a whole-body MRI (1.5 Tesla Magnetom Avanto, Siemens Healthcare Sector, Erlangen). The findings were compared on a lesion-by-lesion basis as part of clinical routine follow-up. RESULTS: 33 patients received a follow-up CT and were evaluated. Overall, 824 lesions were detected. The sensitivity of whole-body MRI was observer-dependent. MRI was slightly less sensitive than CT according to the findings of the two most experienced observers (73.4 % vs. 78.2 %, p = 0.0744). CT was significantly more sensitive in the detection of small (1-5 mm) pulmonary nodules (2.9 % vs. 66.9 %, p < 0.0001). Yet overall, MRI was significantly more specific than CT (83.4 % vs. 50.4 %, p < 0.0001). CONCLUSIONS: Whole-body MRI in compliance with standard requirements for the observers (high level of experience) should be considered as an appropriate alternative to CT without ionizing radiation, particularly for young patients with advanced MM.


Assuntos
Imageamento por Ressonância Magnética , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Imagem Corporal Total , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Evolution ; 40(2): 357-365, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28556033

RESUMO

Northeastern North American populations of the sea anemone Metridium senile show marked differences in levels of genotypic diversity. Comparisons with expectations generated by computer simulation show that some populations are genotypically as diverse as expected for sexually reproducing populations with free recombination, whereas others are significantly less diverse than expected, despite efforts to avoid collecting clonemates. These reductions in diversity are not attributable to the Wahlund effect; they probably result from extensive clonal reproduction. Reduced genotypic diversity may be produced by low rates of recruitment of planktonic larvae, followed by asexual proliferation. The resulting founder effect may account for previously documented random allele-frequency variation between adjacent populations. It is presently uncertain whether the few genotypes found in some populations are particularly well-adapted to local conditions.

15.
Evolution ; 37(2): 423-425, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28568356
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