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1.
Sci Total Environ ; 800: 149513, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392222

RESUMO

Mitigation of erosion along the riverbanks is a global challenge. Stabilisers such as cement can control erosion, but it risks the river ecology. This paper presents the erosion characteristics of riverbank soil treated with two biological stabilisers that alleviate the ecological cost. The riverbank soil of one of the largest river systems, Brahmaputra, is treated by bio-polymeric and bio-cement binders and their composite. Moreover, a novel selective bio-stimulation technique has been employed to achieve bio-mineralisation. The soil stabilisation is assessed by needle penetration tests and CaCO3 contents. The specimens were tested in a flow-controlled hydraulic flume subjected to a critical current profile ranging from 0.06 to 0.62 m/s. Soil samples treated up to four cycles of biocementation have been tested at three different slopes (30°, 45° and 53°). The eroded depth and erosion rate are evaluated with image analysis. Up to four-fold reduction in the erosion rate was observed with biocementation treatment. However, cementation beyond a threshold led to the formation of brittle chunks. A bio-composite was devised through a pre-treatment of low-viscosity biopolymer along with biocementation. The bio-composite was found to effectively mitigate the current-induced erosion with 36% lower ammonia production than the equally erosion resistant biocemented counterpart. The dual characteristics of the bio-composite were confirmed with the microstructural analysis. This study unravels the potential of biopolymer-biocement composite as a sustainable erosion mitigation strategy.


Assuntos
Erosão do Solo , Solo , Rios
2.
Trop Anim Health Prod ; 53(1): 86, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33411090

RESUMO

This study determined the effects of antioxidant supplementation and storage time at cool temperatures on the characteristics of epididymal camel spermatozoa. Camel testes were collected at the abattoir after animal slaughtering and kept at 4 °C during transportation and until processing (max 6 h). Spermatozoa were retrieved and diluted with SHOTOR extender, split in aliquots, supplemented with the following antioxidants: 200 µm/mL vitamin E, 1.0 g/L vitamin C, 1 µg/mL selenium nanoparticles, 50 µg/mL zinc nanoparticles, 2 µg/mL sodium selenite, and 100 µg/mL zinc sulfate, and stored at 4 °C for 2, 48, 96, and 144 h. The storage time significantly affected (P < 0.05) the sperms' motility and livability, the sperms' membrane integrity, and the percentages of cytoplasmic droplets as well as the percentage of morphologically normal spermatozoa. Epididymal sperm characteristics (progressive motility, livability, membrane integrity, and abnormalities) were significantly improved (P < 0.05) when the spermatozoa were diluted with antioxidants as compared with the control group, and the best additives were identified as nano-selenium, sodium selenite, nano-zinc, and zinc sulfate. In conclusion, adding nano-sized minerals or inorganic trace elements and vitamins maintained the progressive motility, livability, and membrane integrity, and decreased abnormalities and cytoplasmic droplet percentages of epididymal camel spermatozoa stored at 4 °C up to 144 h.


Assuntos
Antioxidantes/administração & dosagem , Camelus/fisiologia , Preservação do Sêmen/veterinária , Espermatozoides/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/farmacologia , Masculino , Nanopartículas Metálicas , Distribuição Aleatória , Selênio/administração & dosagem , Selênio/farmacologia , Vitamina E/administração & dosagem , Vitamina E/farmacologia , Zinco/administração & dosagem , Zinco/farmacologia
3.
Animals (Basel) ; 10(1)2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31906462

RESUMO

There are several obstacles in camel semen cryopreservation; such as increasing semen viscosity and the reduction in motile spermatozoa after ejaculation. Epididymal spermatozoa offer an efficient alternative to overcome these problems and are well-suited for artificial insemination in camels. In the current study, we compared the effects of supplementation with vitamin C, E, inorganic trace elements of selenium (Na2SeO3) and zinc (ZnSO4), and zinc and selenium nanoparticles (ZnONPs and SeNPs, respectively) on the cryopreservation of dromedary camel epididymal spermatozoa. When the SHOTOR extender was supplemented with ZnONPs and SeNPs; the sperm showed increased progressive motility; vitality; and membrane integrity after cooling at 5 °C for 2 h; when compared to the control and vitamin-supplemented groups. Moreover, the ZnONPs and SeNPs supplementation improved the progressive motility, vitality, sperm membrane integrity, ultrastructural morphology, and decreased apoptosis when frozen and thawed. SeNPs significantly increased reduced glutathione (GSH), superoxide dismutase (SOD), and decreased lipid peroxide malondialdehyde (MDA) levels. The advantageous effects of the trace elements were potentiated by reduction into a nano-sized particle, which could increase bioavailability and reduce the undesired liberation of toxic concentrations. We recommend the inclusion of SeNPs or ZnONPs to SHOTOR extenders to improve the cryotolerance of camel epididymal spermatozoa.

4.
Nucl Med Commun ; 33(3): 313-21, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22237387

RESUMO

BACKGROUND: The increase in tumor markers with negative or equivocal conventional imaging modalities represents a serious dilemma in the follow-up of previously treated cancer patients. Positron emission tomography/computed tomography (PET/CT) has emerged as a useful tool in oncological imaging in staging and restaging of most cancers. OBJECTIVE: This study explored the potential role of ¹8F-fluorodeoxyglucose (FDG) PET/CT in the detection and localization of tumor recurrence in cancer patients with increasing serum tumor markers and negative or equivocal conventional imaging modalities. MATERIALS AND METHODS: This prospective study was conducted on 105 previously diagnosed and treated cancer patients with different pathologies. All patients were referred for ¹8F-FDG PET/CT scans because of increasing tumor markers with negative or equivocal conventional imaging modalities. All patients underwent whole-body ¹8F-FDG PET/CT scans. The findings were confirmed by clinical and/or radiological follow-up of at least 12 months and histopathologically whenever possible. RESULTS: PET/CT detected recurrence and/or metastases in 90 patients (85.7%), including 17 recurrences, 50 metastases, and 23 recurrences and metastases. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of PET/CT scans were 95.7, 100, 100, 73.3, and 96.2%, respectively. These parameters were 95, 100, 100, 69, and 95% for PET scans alone and were 91.5, 100, 100, 57.9, and 92.3% for CT scans alone. CONCLUSION: ¹8F-FDG PET/CT is a powerful diagnostic tool in restaging of cancer patients. In most cases, PET/CT provides accurate results and helps resolve the clinical dilemma encountered in oncological patients with increasing serum tumor markers and negative or equivocal findings in conventional imaging modalities.


Assuntos
Fluordesoxiglucose F18 , Imagem Multimodal/métodos , Metástase Neoplásica/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X , Imagem Corporal Total/métodos , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias/métodos , Estudos Prospectivos , Sensibilidade e Especificidade
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