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1.
Waste Manag ; 170: 131-143, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37573718

RESUMO

Hydrothermal carbonization (HTC) can mitigate the disposal costs of sewage sludge in a wastewater treatment plant. This study analyzes the impact of integrating HTC with anaerobic digestion (AD) and combustion from a combined energy and economic performance perspective. Net energy balance and investment opportunity are investigated for a number of technical scenarios considering i) different combinations of the technologies: AD + HTC, AD + thermal dryer + combustion, and AD + HTC + combustion, ii) different options for HTC process water treatment: wet oxidation (WO) + AD, and direct return to AD, and iii) different products: heat-only, heat and electricity, hydrochar, and phosphorus. The results show trade-offs between investment cost, self-supplement of heat, and output electricity when WO is used. In AD + HTC, net heat output decreases compared to the reference plant, but avoided disposal costs and hydrochar revenue result in profitable investment when the process water is directly returned to the AD. Although HTC has a lower heat demand than the thermal dryer, replacing the thermal dryer with HTC is only possible when AD, HTC, and combustion are connected, or when WO covers HTC's heat demand. HTC may impair the electricity production because of the necessity for a high-temperature heat source, whereas the thermal dryer can utilize a low-temperature heat source. In conclusion, energy advantages of HTC in AD + HTC + combustion are insufficient to provide a promising investment opportunity due to high investment costs of HTC. The investment opportunity improves by co-combustion of hydrochar and external sludge.

2.
J Environ Manage ; 325(Pt A): 116412, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36274309

RESUMO

Sewage sludge management is torn between a desire for pollution prevention and reuse of a valuable resource. Reconciling these interests in sustainable management is a challenge for researchers. This study focuses on how research on sewage sludge management practices has evolved and scrutinizes how this research is interlinked with concerns and societal issues such as contaminants, economic efficiency, and legislation. Based on published academic papers on sewage sludge management between 1971 and 2019, this study found four trends in research focused on sewage sludge management: a decreasing interest in disposal (landfilling and sea dumping), a dominant interest in land application, a growing interest in sewage sludge as product, and a stable interest in energy recovery. Research on disposal focuses on increasing sludge volumes, legislative changes, and economic challenges with an interest in waste co-treatment. Research on land application concerns nutrient use and contaminants, mainly heavy metals. Research on sewage sludge as a product focuses on the extraction of certain resources and less on use of sewage sludge specifically. Research on energy recovery of sewage sludge focuses on volume reduction rather than contaminants. Two-thirds of the papers are detailed studies aiming to improve single technologies and assessing single risks or benefits. As management of sewage sludge is multifaceted, the narrow focus resulting from detailed studies promotes some concerns while excluding others. Therefore, this study highlights potential gaps such as the combination of nutrient use and disposal and energy recovery and nutrient use.


Assuntos
Metais Pesados , Esgotos , Eliminação de Resíduos Líquidos/métodos , Motivação , Metais Pesados/análise , Poluição Ambiental
3.
Eng Life Sci ; 22(8): 535-549, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35936070

RESUMO

Removal efficiency of gold from a solution of pure tetrachloroaurate ions was investigated using microbial fuel cell (MFC) technology. The effects of type of catholyte solution and initial gold concentration on the removal efficiency were considered. Due to its presence at high levels in the gold wastewater, the effect of copper ions on the removal efficiency of the gold ions was also studied. The effects of pH and initial biomass concentration on the gold removal efficiency was also determined. The results showed that after 5 h contact time, 95% of gold removal efficiency from a wastewater containing 250 ppm of initial gold ions at ambient temperature using 80 g/L yeast concentration was achieved. After 48 h of the cell's operation under the same condition, 98.86% of AuCl4 - ions were successfully removed from the solution. At initial gold concentration in the waste solution of 250 ppm, pH 2, and initial yeast concentration of 80 g/L, 100% removal efficiency of the gold was achieved. On the other hand, the most suitable condition for copper removal was found at a pH of 5.2, where 53% removal efficiency from the waste solution was accomplished.

4.
Environ Sci Pollut Res Int ; 29(40): 61080-61092, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35434755

RESUMO

The novel quaternary CNT/TiO2/WO3/CdS nanostructure was fabricated to be employed in the photocatalytic degradation of reactive blue 19 (RB19) under the visible light irradiation. The physicochemical properties of the pure TiO2, CNT/TiO2, CNT/TiO2/WO3, and CNT/TiO2/WO3/CdS were characterized using XRD, FTIR, FESEM, EDX, DRS, PL, and BET analyses. The photodegradation results showed that the optimum weight percentage of CNT, WO3, and CdS was 4%, 35%, and 5%, respectively. The highest RB19 degradation efficiency of CNT/TiO2/WO3/CdS was achieved 97%. Besides, the central composite design was applied to model and optimize the photocatalytic activity of CNT/TiO2/WO3/CdS nanocatalyst and assess the effects of processing variables including RB19 concentration, catalyst concentration, pH, and irradiation time on the response. RB19 concentration and pH had the most and the second most significant role in the removal efficiency. While increasing the catalyst concentration and irradiation time positively enhanced the removal efficiency to more than 82%, increasing the pH and dye concentration showed the remarkable hindering effects on the removal efficiency by about 45% reduction. The reusability of the synthesized catalysts was studied under the optimum conditions as follows: [RB19] = 25 mg/L, [catalyst] = 1 g/L, pH of 4, and irradiation time = 2 h. The COD and TOC analyses were also conducted during photodegradation process. The COD and TOC removal efficiencies were achieved about 67% and 62%, respectively.

5.
Cancer Biother Radiopharm ; 34(6): 371-379, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30141968

RESUMO

Objective: Acute erythroleukemia (AEL) is a subtype of acute myeloid leukemia (AML), with no specific treatment. Up- or downregulation of long noncoding RNAs (lncRNAs) is strongly associated with the formation and progression of many malignancies. Plasmacytoma variant translocation 1 (PVT1) is a significantly upregulated lncRNA in AML. Antisense locked nucleic acid (LNA) GapmeRs oligonucleotides are the novel tools for targeting lncRNAs. The purpose of the current study was to investigate the functional role of PVT1 antisense LNA GapmeRs on AEL cell line (KG-1). Materials and Methods: AEL cells were transfected with PVT1 antisense LNA GapmeRs at three different time points. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was accomplished to evaluate the PVT1 expression by PVT1 antisense LNA GapmeRs. The viability was evaluated by MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide) assay, and the apoptosis and necrosis were assessed by Annexin V/propidium iodide staining assay. The C-MYC expression level, the target gene of PVT1, was also quantified by qRT-PCR. Results: The results indicated that PVT1 inhibition could significantly decrease the viability of AEL cells, due to induction of apoptosis and necrosis, probably through the downregulation of C-MYC. Conclusions: Their findings suggest that the inhibition of lncRNA PVT1 could serve as a novel approach for controlling the proliferation of AEL cells and could open up a path for treatment of AEL.


Assuntos
Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Eritroblástica Aguda/patologia , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos/farmacologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Longo não Codificante/antagonistas & inibidores , Apoptose , Proliferação de Células , Regulação para Baixo , Humanos , Leucemia Eritroblástica Aguda/tratamento farmacológico , Leucemia Eritroblástica Aguda/genética , Necrose , Proteínas Proto-Oncogênicas c-myc/genética , RNA Longo não Codificante/genética , Células Tumorais Cultivadas
6.
Front Psychol ; 10: 2729, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31920791

RESUMO

According to global data, intimate partner violence and its corresponding impact threaten the lives of almost 35% of women at some point in their life. The aim of this research was to explore the effects of intimate partner sexual violence on women's sense of self-efficacy when it comes to speaking out against violence and seeking help. In-depth interviews and a thematic analysis approach were employed to collect and analyze the data. The participants were 10 women with experiences of intimate partner sexual violence. They were selected through purposive and snowball sampling. Two main themes were drawn from the data, including Exposure and Empowerment. Exposure refers to the type of violence women have experienced and its physical and emotional effects; and Empowerment refers to factors women considered as giving them the courage to speak out against perpetrators, to seek help from others, or to refrain from doing either. It is concluded that Iranian women are not passive when exposed to intimate partner sexual violence, and social support, mainly from family and friends, was a pathway to feelings of empowerment; without this support, women's emotional health is put in jeopardy. Due to the importance of social networks in creating a sense of empowerment, it is recommended that professionals involved in cases of intimate partner sexual violence create an alliance with the women's families and friend and educate them on how to prevent violence or offer help before the violence takes its toll on woman's emotional and physical wellbeing.

7.
Med Oncol ; 34(11): 183, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28956261

RESUMO

Probiotics and fermented milk products have attracted the attention of scientists from various fields, such as health care, industry and pharmacy. In recent years, reports have shown that dietary probiotics such as kefir have a great potential for cancer prevention and treatment. Kefir is fermented milk with Caucasian and Tibet origin, made from the incubation of kefir grains with raw milk or water. Kefir grains are a mixture of yeast and bacteria, living in a symbiotic association. Antibacterial, antifungal, anti-allergic and anti-inflammatory effects are some of the health beneficial properties of kefir grains. Furthermore, it is suggested that some of the bioactive compounds of kefir such as polysaccharides and peptides have great potential for inhibition of proliferation and induction of apoptosis in tumor cells. Many studies revealed that kefir acts on different cancers such as colorectal cancer, malignant T lymphocytes, breast cancer and lung carcinoma. In this review, we have focused on anticancer properties of kefir.


Assuntos
Anticarcinógenos/farmacologia , Kefir , Probióticos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Anticarcinógenos/imunologia , Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Neoplasias da Mama/patologia , Neoplasias da Mama/prevenção & controle , Neoplasias do Colo/dietoterapia , Feminino , Humanos , Fatores Imunológicos/farmacologia , Leucemia/dietoterapia , Leucemia/patologia , Sarcoma/dietoterapia , Sarcoma/patologia
8.
Adv Biomed Res ; 6: 14, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28299306

RESUMO

BACKGROUND: Features of malignant melanoma (MM) vary in the different geographic regions of the world. This may be attributable to environmental, ethnic, and genetic factors. The aim of this study was to determine the expression of estrogen receptor alpha (ER-α) in MM in Isfahan, Iran. MATERIALS AND METHODS: This study was planned as a descriptive, analytical, cross-sectional investigation. During this study, paraffin-embedded tissue blocks of patients with a histopathologic diagnosis of MM was studied for ER-α using immunohistochemistry (IHC). RESULTS: In this study, 38 patients (female/male; 20/18) with a definite diagnosis of malignant cutaneous melanoma and mean age of 52.4 ± 11.2 years were investigated. Using envision IHC staining, there were not any cases with ER-α expression. CONCLUSION: In confirmation to the most previous studies, expression of ER-α was negative in MM. It is recommended to investigate the expression of estrogen receptor beta and other markers in MM.

9.
J Environ Manage ; 184(Pt 2): 204-209, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27717675

RESUMO

Formaldehyde removal from an air stream absorbed into a water stream in a packed bed continuously and then removed by employing a combination of UV and ferrate(VI) as a highly-powerful oxidant in a continuous stirred tank. In addition, the removal of formaldehyde from water was investigated in both batch and continuous modes. The results of the study performed on formaldehyde-contaminated water treatment can be used for both air and water treatment process design. The primary objective of this study is to compare the performance of using UV and ferrate(VI) individually with that of using UV/ferrate(VI) simultaneously to remove formaldehyde from both air and water. Moreover, the effects of several factors such as pH, ferrate(VI) concentration and temperature on formaldehyde removal from water using ferrate(VI) method were evaluated. The results of the current study in batch condition showed that the best initial pH and ferrate(VI) concentration to obtain the highest formaldehyde removal are 2 and 1 mg/l, respectively. The results of this part of research also reveal that temperatures rise from 25 °C to 50 °C increases formaldehyde removal from 69% to 97%; however, further increase in temperature has an adverse effect on removal efficiency. The combination of UV and ferrate(VI) enhances formaldehyde removal efficiency to very close to 100% within 35 min. In continuous air stream treatment, maximum formaldehyde removal of 94% was obtained by using a packed bed scrubber with gas over liquid flow rates ratio of 1.28 m3/m3. Although the results of this study shows that ferrate(VI) method for removal of formaldehyde can be considered as a promising alternative for both water and air treatment, further economic studies are required for this process to be commercialized.


Assuntos
Formaldeído/química , Ferro/química , Águas Residuárias , Poluentes Químicos da Água/química , Recuperação e Remediação Ambiental , Humanos , Raios Ultravioleta
10.
Int J Gynecol Pathol ; 35(2): 153-61, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26840033

RESUMO

Sex cord-like differentiation has been well documented in endometrial stromal tumors. On the basis of the extent of sex cord differentiation, uterine stromal tumors with this kind of differentiation have been classified into 2 subgroups of endometrial stromal tumor with sex cord-like elements and uterine tumors resembling ovarian sex cord tumor. When extensive, this differentiation has been accompanied with indolent clinical behavior and rather good prognosis in most cases. Sex cord differentiation has been rarely observed in uterine mullerian adenosarcoma. Only 3 cases of such occurrence have been reported in the English literature. Herein, we report a case of uterine mullerian adenosarcoma extensively overgrown by uterine tumor resembling ovarian sex cord tumor in a young woman. The presence of an ovarian sex cord tumor component has been confirmed by immunohistochemistry. To the best of our knowledge, this is the second report of such a case in the English literature.


Assuntos
Adenossarcoma/patologia , Neoplasias Uterinas/patologia , Adulto , Biomarcadores Tumorais/análise , Feminino , Humanos , Imuno-Histoquímica , Tumores do Estroma Gonadal e dos Cordões Sexuais/patologia
11.
J Environ Manage ; 170: 186-206, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26829452

RESUMO

Odorous gases are the most important reason that people register complaints with organizations responsible for wastewater collection and treatment systems (WCTS). Although several studies have been conducted for prevention and control of odorous gases, no comprehensive research exists about recent achievements in this area. The aim of the present study is to collect and categorize the new achievements in preventing and controlling odorous gases in WCTS. Two strategies for controlling odor emissions from WCTS are (1) prevention of odor production and (2) removal of odorous compounds from emissions of WCTS. Between the two, priority goes to preventing odorous compounds' production. Several methods have been developed to prevent odor production, such as increasing oxidation reduction potential; inhibiting the activity of sulfide reducing bacteria; chemical removal of hydrogen sulfide; applying formaldehyde and paraformaldehyde to prevent hydrogen sulfide production; and using fuel cells in hydrogen sulfide inhibition and gradual release of oxygen in gas phase by using MgO2 or CaO2. In addition to preventing odorous compounds in WCTS, many other methods have been introduced to remove odorous compounds from emissions of WCTS, such as biofilters; bioscrubbers; biotrickling filters; suspended growth reactors; and membrane bioreactors and scrubbers. Through this review, responsible organizations can find new, effective, and economical strategies to prevent and control odorous gases in WCTS.


Assuntos
Sulfeto de Hidrogênio/química , Odorantes/prevenção & controle , Águas Residuárias , Reatores Biológicos , Compostos de Cálcio/química , Humanos , Óxido de Magnésio/química , Óxidos/química
12.
Iran Biomed J ; 16(1): 25-32, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22562029

RESUMO

BACKGROUND: Hippocampal damages, which are accompanied by inflammation, are among the main causes of epilepsy acquisition. We previously reported that chronic intracerebroventricular (i.c.v.) injection of lipopolysaccharide (LPS) modulates epileptogenesis in rats. There is a network of gap junction channels in the hippocampus that contribute to epileptogenesis. Gap junction channels are formed by oligomeric protein subunits called connexins (Cx). Astrocytic Cx43 and neuronal Cx36 are expressed in the hippocampus. In order to find out the possible role of gap junctions in seizure-modulating effect of LPS and neuroinflammation, we studied the effect of central administration of LPS on expression of Cx36 and Cx43 in rat hippocampus. METHODS: LPS, 2.5 mug/rat/day, was injected i.c.v. to male Wistar rats for 14 days. mRNA and protein abundance of Cx36, Cx43 and IL1-ß were measured in rat hippocampus by real time-PCR, Western blot and ELISA techniques, at the beginning, in the middle, and at the end of the treatment period. RESULTS: IL1-ß protein level was significantly increased 6 h after first injection of LPS. Cx36 and Cx43 mRNA expression did not alter during chronic administration of LPS. A selective decrease in Cx43 protein expression was observed after 7 injections of LPS. CONCLUSION: It is suggested that Cx43 containing gap junctions in the hippocampus is down-regulated in response to chronic injection of LPS. This event can inhibit propagation of toxic and noxious molecules to neighboring cells and modulate hippocampal excitability and epileptogenesis.


Assuntos
Conexina 43/biossíntese , Conexinas/biossíntese , Junções Comunicantes/metabolismo , Hipocampo/metabolismo , Lipopolissacarídeos/administração & dosagem , Animais , Conexina 43/genética , Conexinas/genética , Epilepsia/metabolismo , Epilepsia/patologia , Junções Comunicantes/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Inflamação , Infusões Intraventriculares , Interleucina-1beta/biossíntese , Interleucina-1beta/genética , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Proteína delta-2 de Junções Comunicantes
13.
Talanta ; 60(4): 839-44, 2003 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-18969108

RESUMO

A simple and selective method for rapid and efficient concentration and determination of mug l(-1) levels of Au(III) ions in aqueous solution using octadecyl silica membrane disks modified by pentathia-15-crown-5 and flame atomic absorption spectrometry is presented. The influence of flow rates of eluent and sample solution, amount of ligand, types and least amount of eluent for elution of Au from disks were investigated. Break through volume and limit of detection of the membrane disks modified by 5 mg of the thiacrown ether was found to be 2.0 l and 1.0 mug l(-1), respectively. The effects of various cationic interferences on percent recovery of gold were studied. The method was successfully applied for the determinations of gold in some pharmaceutical samples and for the recovery of trace Au(3+) ions from synthetic and water samples.

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