In situ formation of CuxO/ZnO photocatalysts for efficient simultaneous oxidation of As (III) and adsorption of As (V): Effect of Cu loading.

The introduction of Cu ions onto ZnO leads to alterations in the electrical, optical, and magnetic characteristics of ZnO. These transformations, in turn, result in heightened photocatalytic activity and enhanced stability when employed in the degradation of both organic and inorganic pollutants. Here, a novel photocatalytic-adsorbent system is developed using zinc oxide (ZnO) nanostructures modified with Cu (II) ions in an aqueous solution containing 40 mg/L of As (III). The system utilizes UV-A light (365 nm) as the irradiation source, and the weight percentage of Cu (II) in the composite varies from 0 to 20%. The experimental results reveal significant adsorption of As (III), ranging from 20 to 50%, depending on the solution's Cu (II) content. Remarkably, the ZnO10%Cu composite exhibits the highest photocatalytic activity, achieving 40% adsorption and complete oxidation of As (III) within 25 min of irradiation. Characterization of the composite after the photocatalytic treatment reveals the effective adsorption of As (V) within its structure. Furthermore, no traces of Cu (II) ions are detected in the solution after the reaction, indicating their successful adsorption onto the ZnO surface as Cu (I) and Cu (II) ions. This research marks a significant advancement in harnessing innovative materials for efficient arsenic removal, offering promising insights into the development of novel photocatalytic-adsorbent systems.

Ni-based catalysts used in heterogeneous catalytic ozonation for organic pollutant degradation: a minireview.

Among various advanced oxidation processes for wastewater treatment, heterogeneous catalytic ozonation (HCO) has a growing interest in pollutant degradation, e.g., pesticides, pharmaceuticals, cresols, detergents, polymers, dyes, and others. Direct oxidation with ozone can occur by this route or indirectly, generating reactive oxygen species through the catalytic activation of the ozone molecule. Then, many catalytic materials were evaluated, such as unsupported and supported oxides, activated carbon, nanocarbons, carbon nitride, and mesoporous materials. This review focuses on the properties and performance of Ni-based catalysts (NiO, supported NiO, Ni ferrites, and M-Ni bimetallic), emphasizing the reaction mechanisms and the importance of the reactive oxygen species in removing toxic organic compounds.

Enhancing Free Cyanide Photocatalytic Oxidation by rGO/TiO2 P25 Composites.

Graphene-TiO2 composites have been investigated in various photocatalytic reactions showing successful synergy compared to pristine TiO2. In the present work, graphene oxide (GO) was synthesized by the Hummers method and then reduced graphene oxide-TiO2 composites (rGO/TiO2) were obtained by an in situ GO photoreduction route. X-ray diffraction, FTIR, Raman, UV-vis DRS, and photoluminescence were the main characterization techniques. The obtained composites containing 1 and 3 wt.% rGO were evaluated in the cyanide (50 mg/L) oxidation and Au-cyanide complex (300 mg/L) degradation under UV-A light. The composites showed higher photocatalytic activity than TiO2, mainly with the 1% rGO content. Cyanate and gold nanoparticles, deposited on the photocatalyst's surface, were the main byproducts during the photocatalyst assessment. The improved photocatalytic activity of the composites was attributed to a higher rate of electron transfer and a lower rate of charge recombination due to the chemical interaction of rGO with TiO2.

Preparation of Poly(vinyl Alcohol) Microparticles for Freeze Protection of Sensitive Fruit Crops.

Poly(vinyl alcohol) (PVA) displays ice recrystallization inhibition (IRI) properties as many antifreeze proteins found in cold tolerant organisms. The molecular architecture and composition (molecular weight and distribution of pendant OH and acetate groups) have been studied to improve the antifreezing properties of PVA, suggesting that the molecular architecture of PVA plays an important role in IRI activity. The present work deals with the preparation of PVA microparticles using an alkaline treatment. The effect of PVA molecular weight on the morphology and antifreezeing properties of PVA microparticles was investigated. The antifreezeing property of PVA microparticles on the susceptibility of flower bud tissues to freeze damage was also evaluated. The alkaline treatment of an aqueous PVA solution produced stable polymer chain aggregates with spherical shapes. The average size of the PVA microparticles increased significantly with the increasing molecular weight of the PVA macromolecule precursor. The PVA microparticles inhibited the growth of ice crystals and blocked ice growth at concentrations as low as 0.01 % w/v. The effect of impeding ice crystal growth by preventing the joining of adjacent ice crystals is attributed to the larger size of the PVA particles adsorbed on the ice surface compared to the aggregated PVA macromolecules in saline solution. The thermal hysteresis activity of PVA macromolecules and microparticles was not detected by differential scanning calorimetry analysis. The PVA microparticles reduced the incidence of freeze injuries in flower bud tissues by 55% and their application, considering the low toxicity of PVA, has a high potential for freeze protection in fruit crops.

4-nitrophenol optical sensing with N doped oxidized carbon dots.

In this work, we report a facile strategy for 4-nitrophenol (4-NP) sensing using highly luminescent nitrogen-doped oxidized carbon dots. The quenching of fluorescence (turn OFF), with the addition of trace amounts of organic pollutant (4-NP) in NOCDs, has been attributed to the complete reduction of nitrogen-doped oxidized carbon dots (NOCDs) to reduced nitrogen-doped oxidized carbon dots (rNOCDs) and its formation was confirmed by infrared, X-ray diffraction and X-ray photoelectron spectroscopy measurements. The chemical changes in oxygen-containing functional groups of NOCDs, in the presence of 4-NP, are elucidated and corresponding characterization through XPS reveals the changes in the peak intensities of CC (284.5 eV) and OCO (288.6 eV), indicating a decrement in hydroxyl groups that hinder its complete reduction to NOCDs. The sensitivity of NOCDs towards 4-NP has been tested in spiked tap water in the concentration range 2 µM to 2 mM with the minimum detection limit of 2 µM (linear detection range from 2 to 100 µM with regression coefficient R2 =0.99). The proposed simple sensing platform can be used to reduce NOCDs and simultaneously sense low concentrations of 4-NP. Finally, an effective treatment to improve the reduction of nitrogen-doped graphene oxide is proposed.

Disminución de la seroprevalencia del virus de la hepatitis A en Santiago de Chile, comparación de una década / Decrease in seroprevalence of hepatitis A virus in Santiago, Chile: A decade-long comparison

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Photosensitized oxidation of 9,10-dimethylanthracene with singlet oxygen by using a safranin O/silica composite under visible light.

The photosensitized oxidation of 9,10-dimethylanthracene with singlet oxygen in acetonitrile was investigated using a safranin O/silica composite as an heterogeneous delivery system of the photosensitizer. The only detected product was the corresponding endoperoxide (9,10-endoperoxianthracene) and its formation rate depended on the initial concentration of DMA, the light intensity and the amount of the composite. The kinetics of this reaction was compared with that of the reported kinetic model of photosensitized oxidations of organic compounds in homogeneous reactions. It was found that both reactions followed the same model, suggesting that the actual reaction between photoproduced singlet oxygen and 9,10-dimethylanthracene was performed in homogeneous media and the surface of the composite was not involved in the reaction.

Reactivity of NiO for 2,4-D degradation with ozone: XPS studies.

2,4-Dichlorophenoxyacetic acid (2,4-D) is usually used as a refractory model compound that requires a prolonged reaction time for mineralization. In this study, we found that nickel oxide (NiO) significantly improved 2,4-D degradation and mineralization in reaction with ozone. Other metal oxides, such as titania, silica and alumina, were also tested in this reaction, so that, the mineralization degree was almost the same for all of them (ca. 25%), whereas NiO showed more than 60% in 1h. These outstanding results led us to study in more depth the role of NiO as catalyst in the degradation of 2,4-D. For instance, the optimum NiO loading amount was 0.3 g L(-1). The catalytic ozonation showed a high stability after three reaction cycles. With the aim of identifying the surface species responsible for the high activity of NiO, besides knowing the byproducts during the degradation of 2,4-D, XPS and HPLC were mainly used as analytical tools. According to the results, the mineralization of 2,4-D was directly influenced by the adsorbed chlorate organic compounds and oxalate group onto NiO. Therefore, NiO plays a true role as a catalyst forming surface compounds which are subsequently decomposed causing an increase in the mineralization efficiency. In addition, it was possible to identify several degradation byproducts (2,4-diclorophenol, glycolic, fumaric, maleic and oxalic acids) that were included in a rational reaction pathway. It was proposed that 2,4-D elimination in presence of NiO as catalyst is a combination of processes such as: conventional ozonation, indirect mechanism (OH) and surface complex formation.

Angiogenic properties of adult human thymus fat.

The endogenous proangiogenic properties of adipose tissue are well recognized. Although the adult human thymus has long been known to degenerate into fat tissue, it has never been considered as a potential source of angiogenic factors. We have investigated the expression of diverse angiogenic factors, including vascular endothelial growth factor A and B, angiopoietin 1, and tyrosine-protein kinase receptor-2 (an angiopoietin receptor), and then analyzed their physiological role on endothelial cell migration and proliferation, two relevant events in angiogenesis. The detection of the gene and protein expression of the various proteins has been performed by immunohistochemistry, Western blotting, and quantitative real-time polymerase chain reaction. We show, for the first time, that adult thymus fat produces a variety of angiogenic factors and induces the proliferation and migration of human umbilical cord endothelial cells. Based on these findings, we suggest that this fat has a potential angiogenic function that might affect thymic function and ongoing adipogenesis within the thymus.

[Prevalence of hypokalemia in patients with methylprednisolone pulse therapy]. / Prevalencia de hipokalemia en pacientes tratados con pulsos de metilprednisolona.

OBJECTIVE: To determine the prevalence of hypokalemia in patients with methylprednisolone pulse therapy. DESIGN: We carried out a descriptive, cross-sectional study. MATERIAL AND METHODS: We enrolled 110 outpatients who received pulse doses of 1 g of intravenous methylprednisolone for three consecutive days. Demographic variables, serum electrolytes and an electrocardiogram were documented. RESULTS: The study group consisted of 31 men (28.2%) and 79 women (71.8%). Average age was 40 +/- 13.6 years. Mild hypokalemia was present in 19 patients (17.27% [95% CI 9.75-24.79]); moderate potassium levels were found in just one patient 0.9% [IC 95 0.023-4.96]); no cases of severe hypokalemia occurred. Total prevalence was 18.18% (95% CI 10.5-25.8). There were no significant electrocardiographic changes. DISCUSSION AND CONCLUSION: Mild and moderate hypokalemia was 18.18% without clinical or electrocardiographic consequences. Since there were no cases of severe hypokalemia, close monitoring of potassium levels should be restricted to those patients with other risk factors.

Seroprevalence of selected viral, bacterial and parasitic infections among inpatients of a public psychiatric hospital of Mexico.

We sought to determine the frequency of serological markers of selected infections in a population of psychiatric patients in Durango City, Mexico, and to determine whether there are any epidemiological characteristics of the subjects associated with the infections. One hundred and five inpatients of a public psychiatric hospital of Durango were examined for HBsAg, anti-HCV antibodies, anti-HIV antibodies, anti-Brucella antibodies, rapid plasma reagin and anti-Cysticercus antibodies by commercially available assays. Anti-Cysticercus antibodies were confirmed by Western blot and HBsAg by neutralization assay. Epidemiological data from each participant were also obtained. Seroprevalences of HBsAg, anti-HCV, anti-HIV, anti-Brucella, rapid plasma reagin and anti-Cysticercus antibodies found were 0.0%, 4.8%, 0.9%, 0.0%, 1.9%, and 0.9%, respectively. Overall, 9 (8.6%) inpatients showed seropositivity to any infection marker. We concluded that our psychiatric inpatients have serological evidence of a number of infections. HCV is an important pathogen among our psychiatric inpatients. Health care strategies for prevention and control of infections in Mexican psychiatric patients should be considered.

Seroprevalence of selected viral, bacterial and parasitic infections among inpatients of a public psychiatric hospital of Mexico / Soroprevalência de infecções virais bacterianas e parasíticas nos pacientes internados em hospital público psiquiátrico do México

We sought to determine the frequency of serological markers of selected infections in a population of psychiatric patients in Durango City, Mexico, and to determine whether there are any epidemiological characteristics of the subjects associated with the infections. One hundred and five inpatients of a public psychiatric hospital of Durango were examined for HBsAg, anti-HCV antibodies, anti-HIV antibodies, anti-Brucella antibodies, rapid plasma reagin and anti-Cysticercus antibodies by commercially available assays. Anti-Cysticercus antibodies were confirmed by Western blot and HBsAg by neutralization assay. Epidemiological data from each participant were also obtained. Seroprevalences of HBsAg, anti-HCV, anti-HIV, anti-Brucella, rapid plasma reagin and anti-Cysticercus antibodies found were 0.0 percent, 4.8 percent, 0.9 percent, 0.0 percent, 1.9 percent, and 0.9 percent, respectively. Overall, 9 (8.6 percent) inpatients showed seropositivity to any infection marker. We concluded that our psychiatric inpatients have serological evidence of a number of infections. HCV is an important pathogen among our psychiatric inpatients. Health care strategies for prevention and control of infections in Mexican psychiatric patients should be considered.

Procuramos determinar a frequência de marcadores sorológicos de infecções em pacientes psiquiátricos da cidade de Durango, México e determinar se existem características epidemiológicas dos pacientes que podem ser associados a estas infecções. Cento e cinco pacientes internados neste hospital psiquiátrico de Durango foram examinados para HBsAg, anticorpos anti-HCV, anticorpos anti-HIV, anticorpos anti-Brucella, reaginas plasmáticos imediatas e anticorpos anti-Cysticercus por testes comerciais. Os anticorpos anti-Cysticercus foram confirmadoss por Western Blot e o HbsAg por testes de neutralização. Dados epidemiológicos de cada participante foram também obtidos. Soroprevalências encontradas de HbsAg, anti-HCV, anti-HIV, anti-Brucella, reagina plasmática imediata e anticorpos anti-Cysticercus foram respectivamente 0,0 por cento, 4,8 por cento, 0,9 por cento, 0,0 por cento, 1,9 por cento e 0,9 por cento. No conjunto, 9 (8,6 por cento) de pacientes internados mostraram soropositividade para marcador infeccioso. Concluímos que nossos pacientes psiquiátricos internados têm evidência sorológica de infecções. HCV é um patógeno importante entre os pacientes psiquiátricos internados. Estratégias de saúde pública para prevenção e controle de infecções em pacientes psiquiátricos do México devem ser consideradas.

Seroepidemiology of Toxoplasma gondii infection in psychiatric inpatients in a northern Mexican city.

BACKGROUND: Patients with psychiatric disorders were found to show a high seroprevalence of Toxoplasma gondii infection. There is scarce information about the epidemiology of T. gondii infection in psychiatric patients in Mexico. Therefore, we sought to determine the prevalence of T. gondii infection and associated socio-demographic, clinical and behavioural characteristics in a population of psychiatric patients in Durango City, Mexico. Seroprevalence in patients was compared with that obtained in a control population. METHODS: One hundred and thirty seven inpatients of a public psychiatric hospital and 180 controls were examined for the presence of IgG and IgM antibodies against T. gondii by enzyme-linked immunoassay (Diagnostic Automation Inc., Calabasas, CA, USA). The control population consisted of blood donors of a public blood bank and elderly persons attending a senior center in the same city. Age in controls (42 years +/- 20.2) was comparable with that of the psychiatric patients (43.7 years +/-13.8) (p = 0.42). Socio-demographic, clinical and behavioral characteristics from the patients were also obtained. RESULTS: Anti-T. gondii IgG antibodies indicating latent infection with T. gondii was found in 25 (18.2%) of 137 psychiatric inpatients and 16 (8.9%) of 180 controls (p = 0.02). Ten (26.3%) of 38 schizophrenic patients had latent infection and this prevalence was also significantly higher than that observed in controls (p = 0.005). Prevalence of anti-T. gondii IgM antibodies was comparable among patients and controls (4.4% vs 2.2%, respectively, p = 0.22). Multivariate analysis showed that T. gondii infection in inpatients was positively associated with sexual promiscuity (adjusted OR = 15.8; 95% CI: 3.8-64.8), unwashed raw fruit consumption (adjusted OR = 5.19; 95% CI: 2.3-11.3), and a history of surgery (adjusted OR = 6.5; 95% CI: 2.6-16), and negatively associated with lamb meat consumption (adjusted OR = 0.26; 95% CI: 0.10-0.63). CONCLUSION: In the present study, psychiatric inpatients in Durango, Mexico, in general and schizophrenia inpatients in particular had a significantly higher prevalence of T. gondii infection than the control group. Results suggest that unwashed raw fruit consumption might be the most important route of T. gondii transmission in our psychiatric inpatients while lamb meat consumption the less important. Additional studies will have to elucidate the causative relation between infection with T. gondii and psychiatric disorders.

The Chilean AIDS cohort: a model for evaluating the impact of an expanded access program to antiretroviral therapy in a middle-income country--organization and preliminary results.

Chile, middle-income country with 15 million people, began an expanded access program (EAP) to antiretroviral therapy (ART) in 2001. EAP provides ART, monitoring, and funding for management of associated complications in 32 points of care. A national cohort (Chilean AIDS Cohort [ChiAC]), enrolling 98% of these patients, was created for standardized treatment and impact evaluation. Information exchange is mainly through the Internet. By December 2004, the ChiAC had 4365 participants (83.3% male). At baseline, 47.5% had clinical AIDS, 26.2% were asymptomatic, 80.2% had a CD4 count <200 cells/mm and 58.2% were ART naive; in these patients, the most frequent regimen is zidovudine, lamivudine, and efavirenz. A 6-month follow-up in 1057 patients showed a global mortality of 5% (0.5% if patients were asymptomatic at baseline and 8.3% if patients had baseline AIDS). There was a similar risk of death if the baseline CD4 count was 100 to 200 cells/mm or >200 cells/mm ( approximately 1%), but this increased to 4.8% (relative risk [RR] = 5.2) and 10.7% (RR = 11.5) if the CD4 count was 51 to 100 cells/mm or

Hepatitis B virus infection among inpatients of a psychiatric hospital of Mexico.

BACKGROUND: The epidemiology of the hepatitis B virus (HBV) infection in psychiatric patients from developing countries is poorly studied. Therefore, we sought to determine the frequency of HBV surface antigen (HBsAg) and HBV surface antibody (HBsAb) serological markers of HBV infection in a population of patients of a psychiatric hospital in Durango City, Durango, Mexico, and to determine whether there are any epidemiological characteristics of the subjects associated with the infection. METHODS: Out of 150 patients of the psychiatric hospital of Durango City, 99 were examined for HBsAg and HBsAb by AUSZYME MONOCLONAL (Abbott Laboratories, Abbott Park, IL, USA) assay and AUSAB (Abbott Laboratories, Abbott Park, IL, USA) assay, respectively. Epidemiological data from each participant was also obtained. For comparison purposes, 2505 blood donors were examined for HBsAg seropositivity. RESULTS: Out of the 99 patients studied, twelve showed serological evidence of HBV infection (12.1%); 7 of them (7.1%) were positive for HBsAg, and 5 (5.1%) were positive for HBsAb. Out of the 2505 blood donors, 2 (0.0008%) were HBsAg positive. Seropositivity to HBV markers was associated with an age of 45 years and older (OR = 4.27; 95%CI = 1.02-18.78). Other characteristics as gender, number of hospitalizations, duration of the last hospitalization, and clinical diagnosis were not associated with seropositivity to HBV infection markers. Patients showed a significantly higher HBsAg seropositivity than blood donors (p < 0.0000001). CONCLUSION: HBV was found to be an important infectious agent in the Mexican psychiatric inpatient population studied. Health care strategies for prevention and control of HBV infection in psychiatric hospitals should pay special attention to patients aged forty-five years and older.

Inmunoterapia intravesical con BCG en el carcinoma superficial de células transicionales de la vejiga / Intravesical immunotherapy with BCG in bladder superficial transitional cell carcinoma

Se realizó un estudio prospectivo para conocer la eficacia del BCG intravesical como tratamiento en el carcinoma superficial del la vejiga de células transicionales y para prevenir la recurrencia de esta clase de tumores. Se trataron siete pacientes (seis varones y una mujer) con carcinoma superficial de vejiga de células transicionales estadio A, grado II, con promedio de edad de 61.2 años. Se utilizó la cepa danesa 1331 a dosis de 50 mg en 50 ml, equivalente a 500 y 1 000 millones de BCG. El esquema inicial consistió en la aplicación de 50 mg por semana durante seis semanas. Los pacientes con mayor riesgo de recurrencia se sometieron a esquema mensual de sostén. El seguimiento fue de 7.6 meses, a partir de la primera dosis, mediante vigilancia trimestral con cistoscopia, examen general de orina, urocultivo y citologías urinarias. La respuesta es de 100 por ciento, según lo establecido por el protocolo de los autores. Un paciente presentó recidiva después de haber recibido el ciclo inicial, y se sometió a un esquema de reinducción previa y RTU de tumor. Actualmente se encuentra libre de actividad tumoral. Este protocolo muestra prácticamente los mismos resultados de comparación con otros estudios sobre BCG sólo que con diferentes dosis y esquema de seguimiento

Project setiq

This paper provides comprehensive information on the environmental response to a fire at the pesticide warehouse in Canning, Novoa Scotia on 31 May, 1986. The incident is described in detail. The roles and activities of the agencies involved are discussed and observations made. Results of the sampling, analytical and clean-up efforts are highlighted. Pesticide levels in milk, drinking water, run-off water, soils, biota and in the habitant river are provided. (AU)