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1.
Article in English | WPRIM (Western Pacific) | ID: wpr-1013411

ABSTRACT

Objectives@#This preliminary study determined the prevalence of HIV infection among patients with newly diagnosed solid and hematologic malignancies at the Philippine General Hospital - Cancer Institute. @*Methods@#Adult Filipinos aged 19 years and above with biopsy- or imaging-confirmed malignancy and for chemotherapy, seen at the adult medical oncology and hematology clinic from January to September 2021 were included. Demographic and clinical data were obtained using a questionnaire. Rapid HIV screening was performed using blood extracted via finger prick. Pre- and post-test counselling were conducted. @*Results@#Of the 124 patients included in our study, majority were female (91, 73.4%), and 45 years old and above with a median age of 49 (20 – 74). Majority had solid tumors (121, 97.6%) with breast cancer being the most common (67, 54.0%) followed by colorectal (18, 14.5%), and head and neck cancer (14, 11.3%). Among those with hematologic malignancies, two had acute myelogenous leukemia and one had multiple myeloma. Six patients had AIDS-defining malignancies (NHL, cervical cancer). HIV risk factors and associated conditions were present in 18 patients (14.5%). Ten patients reported prior HIV testing. None of the patients tested positive for HIV. @*Conclusion@#The absence of HIV cases detected in our cohort may be due to the low prevalence of HIV risk factors and associated conditions. At this time, there is insufficient evidence to routinely recommend HIV testing among newlydiagnosed cancer patients. However, physicians are encouraged to offer HIV testing to cancer patients, especially to those with HIV risk factors, given the benefits of early detection and management of HIV.


Subject(s)
HIV , Philippines , Neoplasms , Mass Screening
2.
Materials (Basel) ; 16(23)2023 Nov 24.
Article in English | MEDLINE | ID: mdl-38068072

ABSTRACT

This work is dedicated to the study of the effect of the synthesis conditions (drying and calcination) of sulfated zirconia on the final catalytic behavior of bifunctional composite catalysts prepared by the physical mixing of the sulfated zirconia (methanol dehydration catalyst) with Cu/ZnO/Al2O3 (CZA; methanol synthesis catalyst). The main objective was to optimize the CZA-ZrO2/SO42- composite catalyst for its use in the direct production of dimethyl ether (DME) from syngas. Sulfated zirconia aerogel (AZS) and xerogel (XZS) were prepared using the sol-gel method using different solvent evacuation conditions and calcination temperatures, while the Cu-ZnO(Al) catalyst was synthesized using the coprecipitation procedure. The effectivity of CZA-ZrO2/SO42- composite catalysts for the direct production of dimethyl ether (DME) from syngas was evaluated in a flow reactor at 250 °C and 30 bar total pressure. The characterization of the sulfated zirconia aerogels and xerogels using different techniques showed that the mesoporous aerogel (AZS0.5300) exhibited the best textural and acidic properties due to the gel drying under supercritical conditions and calcination at 300 °C. As a result, the composite catalyst CZA-AZS0.5300 exhibited seven times higher DME production than its xerogel-containing counterpart (364 vs. 52 µmolDME·min-1·gcat-1). This was attributed to its well-matched metal surface, mesoporous structure, optimal crystallite size and, most importantly, its higher acidity.

3.
Sci Rep ; 13(1): 5444, 2023 04 03.
Article in English | MEDLINE | ID: mdl-37012265

ABSTRACT

Crop improvement is a key innovation area in the pursuit of sustainable food systems. However, realising its potential requires integration of the needs and priorities of all agri-food chain stakeholders. In this study, we provide a multi-stakeholder perspective on the role of crop improvement in future-proofing the European food system. We engaged agri-business, farm- and consumer-level stakeholders, and plant scientists through an online survey and focus groups. Four of each group's top five priorities were shared and related to environmental sustainability goals (water, nitrogen and phosphorus efficiency, and heat stress). Consensus was identified on issues including considering existing alternatives to plant breeding (e.g. management strategies), minimising trade-offs, and addressing geographical variation in needs. We conducted a rapid evidence synthesis on the impacts of priority crop improvement options, highlighting the urgent need for further research examining downstream sustainability impacts to identify concrete targets for plant breeding innovation as a food systems solution.


Subject(s)
Plant Breeding , Focus Groups , Farms
4.
Materials (Basel) ; 15(19)2022 Sep 30.
Article in English | MEDLINE | ID: mdl-36234126

ABSTRACT

To achieve sulfur content in gas oil at a near-zero level, new catalysts with improved hydrogenation functions are needed. In this work, new Ni-Mo-Mo hydrodesulfurization (HDS) catalysts supported by Al2O3-CeO2 materials were synthesized to evaluate their efficiency in the reaction of HDS with dibenzothiophene (DBT). Al2O3-CeO2 supports different CeO2 loadings (0, 5, 10 and 15 wt.%) and supported NiMoW catalysts were synthesized by sol-gel and impregnation methods, respectively. The physicochemical properties of the supports and catalysts were determined by a variety of techniques (chemical analysis, XRD, N2 physisorption, DRS UV-Vis, XPS, and HRTEM). In the DBT HDS reaction carried out in a batch reactor at 320 °C and a H2 pressure of 5.5 MPa, the sulfide catalysts showed a dramatic increase in activity with increasing CeO2 content in the support. Nearly complete DBT conversion (97%) and enhanced hydrogenation function (HYD) were achieved on the catalyst with the highest CeO2 loading. The improved DBT conversion and selectivity towards the hydrogenation products (HYD/DDS ratio = 1.6) of this catalyst were attributed to the combination of the following causes: (i) the positive effect of CeO2 in forcing the formation of the onion-shaped Mo(W)S2 layers with a large number of active phases, (ii) the inhibition of the formation of the undesired NiAlO4 spinel phase, (iii) the appropriate textural properties, (iv) the additional ability for heterolytic dissociation of H2 on the CeO2 surfaces, and (v) the increase in Brønsted acidity.

5.
Environ Res ; 214(Pt 4): 114094, 2022 11.
Article in English | MEDLINE | ID: mdl-36029840

ABSTRACT

The synthesis of anatase TiO2 nanoparticles with controlled morphology and increased {001} facets exposed without the presence of fluorine-derived substances is a challenge. Herein, we report a highly effective approach to fabricate anatase TiO2 nanoplates with exposed {001} facets and their exploitation as robust photocatalytic materials for dye remediation. These materials were synthesized under controlled hydrolysis and condensation reactions, using titanium (IV) n-butoxide in an ethanolic solution, with acetic and sulfuric acids, by a solvothermal method at 190 °C with or without the presence of the non-ionic surfactant Triton® X-100 and then characterized. During TiO2 crystal synthesis, the effect of a non-ionic surfactant on the TiO2 particle growth was investigated. Our results demonstrate that the proposed method can synthesize pure and crystalline anatase TiO2 square nanoplates that form nanostructured spheres with high surface area, uniformly sized mesopores, and exposed {001} facets. The presence of non-ionic surfactant increased the exposed {001} facets percentage of the formed nanoplates from 69 to 80%, decreased the crystallite thickness, but unaffected its crystalline phase and band gap energy. The kinetic constants (Ka e Kb) for the synthesized TiO2 anatase nanoplates are considerably higher than the commercial TiO2 anatase constant (Kc). The synthesized photocatalysts show higher efficiency in the photocatalytic removal of methylene blue (MB) than commercial TiO2 (for t = 120 min).


Subject(s)
Methylene Blue , Titanium , Catalysis , Methylene Blue/chemistry , Surface-Active Agents , Titanium/chemistry
6.
Ophthalmologica ; 244(4): 315-325, 2021.
Article in English | MEDLINE | ID: mdl-33596579

ABSTRACT

PURPOSE: The aim of the study was to characterize the morphological features of polypoidal choroidal vasculopathy (PCV) in a large Caucasian population. METHODS: We conducteda multicenter, cross-sectional study of treatment-naïve patients with PCV. Baseline fundus photography, spectral-domain optical coherence tomography (SD-OCT), fluorescein angiography (FA), and indocyanine green angiography (ICGA) were assessed by trained medical graders. Typical PCV features were explored, and retinal thickness (RT) and choroidal thickness (CT) measurements were performed. RESULTS: Seventy-nine eyes of 73 patients (mean age, 72.6 ± 11.9 years) were included. ICGA identified macular polyps in 89.9% of cases. SD-OCT revealed mostly subretinal fluid (93.6%) and a retinal pigment epithelium (RPE) detachment in 91.4%, with sharp protrusion in 67.0% of cases. Polyp-like structures were seen in 74.3% of cases, mostly adherent to an elevated RPE (69.6%). Type 1 neovascularization (NV) was identified in 74.7% of patients, while 16.5% had a mixed NV. The mean macular CT was 220.9 ± 83.2 µm (range, 67.9-403.6). Diffuse and focal pachychoroid were observed in 26.6 and 30.4% of patients, respectively. Soft drusen were reported in 62.0% of cases, but retinal hemorrhage occurred in only 19.0% of cases. CONCLUSION: The morphological features of PCV in Caucasians are similar to those reported in Asians. Pachychoroid signs were found in nearly half of our cohort. However, the mean age at presentation, high prevalence of soft drusen, and low prevalence of large subretinal hemorrhages make PCV closer to age-related macular degeneration in this ethnic group.


Subject(s)
Choroidal Neovascularization , Polyps , Aged , Aged, 80 and over , Choroid/pathology , Choroidal Neovascularization/pathology , Coloring Agents , Cross-Sectional Studies , Fluorescein Angiography , Humans , Indocyanine Green , Middle Aged , Polyps/diagnosis , Retrospective Studies , Tomography, Optical Coherence
7.
Retina ; 41(2): 345-354, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-32453069

ABSTRACT

PURPOSE: To study the role of serum biomarkers as prognostic factors for qualitative and quantitative response to anti-vascular endothelial growth factor injections for diabetic macular edema (DME). METHODS: Sixty-seven eyes with DME were treated with intravitreal bevacizumab during a 12-month follow-up period. All cases underwent a baseline workup consisting of 12 inflammatory, metabolic and prothrombotic factors. The following outcomes were evaluated at 3-month intervals until 1 year of follow-up: visual acuity, central subfield thickness (CST), macular volume (MV), % of change from baseline in CST, occurrence of a CST change < 10%, a CST change >20%, and a CST <330 µm, achieving an improvement ≥2 lines of visual acuity, achieving visual acuity ≥20/40. RESULTS: A significant improvement in CST and visual acuity was seen from third month onwards. Twenty-eight (48.1%) cases were classified as "early responders," 24 (35.8%) as "late responders", and 15 (22.4%) as "poor responders." Serum vascular endothelial growth factor-A levels were significantly lower in "poor responders" (P = 0.006). C-reactive protein (hsCRP) was associated with a limited anatomic response (<10% CST change) (P = 0.002, OR = 1.845, cutoff value of hsCRP = 1.84 mg/L). hsCRP was also negatively associated with obtaining a final CST <330 µm (P = 0.04, r2 = 0.112, OR = 0.643). Baseline visual acuity was significantly associated with 12th month visual acuity (P < 0.001, r2 = 0.602) and also with an improvement ≥2 visual acuity lines (P = 0.009, OR = 20.54). CONCLUSION: Increased high-sensitivity C-reactive protein was associated with limited anatomic response to anti-vascular endothelial growth factor treatment and persistent DME. Poor responders had significantly lower values of serum vascular endothelial growth factor-A, suggesting an alternative pathogenic pathway for persisting DME.


Subject(s)
Bevacizumab/administration & dosage , Diabetic Retinopathy/drug therapy , Macula Lutea/pathology , Macular Edema/drug therapy , Ranibizumab/administration & dosage , Tomography, Optical Coherence/methods , Visual Acuity , Aged , Angiogenesis Inhibitors/administration & dosage , Diabetic Retinopathy/complications , Diabetic Retinopathy/diagnosis , Female , Follow-Up Studies , Humans , Macular Edema/diagnosis , Macular Edema/etiology , Male , Middle Aged , Prospective Studies , Treatment Outcome , Vascular Endothelial Growth Factor A/antagonists & inhibitors
8.
Sci Rep ; 10(1): 2594, 2020 02 13.
Article in English | MEDLINE | ID: mdl-32054880

ABSTRACT

Ocean acidification is expected to have detrimental consequences for the most abundant calcifying phytoplankton species Emiliania huxleyi. However, this assumption is mainly based on laboratory manipulations that are unable to reproduce the complexity of natural ecosystems. Here, E. huxleyi coccolith assemblages collected over a year by an autonomous water sampler and sediment traps in the Subantarctic Zone were analysed. The combination of taxonomic and morphometric analyses together with in situ measurements of surface-water properties allowed us to monitor, with unprecedented detail, the seasonal cycle of E. huxleyi at two Subantarctic stations. E. huxleyi subantarctic assemblages were composed of a mixture of, at least, four different morphotypes. Heavier morphotypes exhibited their maximum relative abundances during winter, coinciding with peak annual TCO2 and nutrient concentrations, while lighter morphotypes dominated during summer, coinciding with lowest TCO2 and nutrients levels. The similar seasonality observed in both time-series suggests that it may be a circumpolar feature of the Subantarctic zone. Our results challenge the view that ocean acidification will necessarily lead to a replacement of heavily-calcified coccolithophores by lightly-calcified ones in subpolar ecosystems, and emphasize the need to consider the cumulative effect of multiple stressors on the probable succession of morphotypes.

9.
Acta Medica Philippina ; : 120-124, 2020.
Article in English | WPRIM (Western Pacific) | ID: wpr-979727

ABSTRACT

Key Findings@#• Very low-quality evidence from a single retrospective study suggests that continuous renal replacement therapy (CRRT) may reduce mortality among COVID-19 patients on invasive mechanical ventilation. Guidelines recommend CRRT for critically ill patients to minimize the risk of possible transmission, if this option is available. • Although uncommon, acute kidney injury (AKI) can occur in association with coronavirus disease 2019 (COVID-19) and is associated with increased in-hospital mortality. • There are currently no published or ongoing clinical trials directly comparing dialysis modalities for acute kidney injury in COVID-19 patients. • In reducing the risk of transmission during dialysis: currently, there are no studies comparing one dialysis modality to another. The method of dialysis is still primarily determined by the clinical picture of the patient, the expertise of the center, and the resources available. The American Society of Nephrology (ASN) recommends CRRT over intermittent hemodialysis (IHD) for critically ill patients with COVID-19 to minimize patient contact when it is available, and resources allow. Otherwise, intermittent hemodialysis may be done provided that, infection control measures are strictly followed. • Several international and local guidelines recommend strict adherence to infection prevention and control measures (e.g. hand hygiene, physical distancing, proper use of personal protective equipment (PPE), and cohorting of patients) who are undergoing dialysis.


Subject(s)
COVID-19
10.
Sci Total Environ ; 693: 133531, 2019 Nov 25.
Article in English | MEDLINE | ID: mdl-31635016

ABSTRACT

Hydrological monitoring is essential to guide evidence-based decision making necessary for sustainable water resource management and governance. Limited hydrometric datasets and the pressure on long-term hydrological monitoring networks make it paramount to explore alternative methods for data collection. This is particularly the case for low-income countries, where data scarcity is more pronounced, and where conventional monitoring methods are expensive and logistically challenging. Citizen science in hydrological research has recently gained popularity and crowdsourced monitoring is a promising cost-effective approach for data collection. Citizen science also has the potential to enhance knowledge co-creation and science-based evidence that underpins the governance and management of water resources. This paper provides a comprehensive review on citizen science and crowdsourced data collection within the context of hydrology, based on a synthesis of 71 articles from 2001 to 2018. Application of citizen science in hydrology is increasing in number and breadth, generating a plethora of scientific data. Citizen science approaches differ in scale, scope and degree of citizen involvement. Most of the programs are found in North America and Europe. Participation mostly comprises a contributory citizen science model, which engages citizens in data collection. In order to leverage the full potential of citizen science in knowledge co-generation, future citizen science projects in hydrology could benefit from more co-created types of projects that establish strong ties between research and public engagement, thereby enhancing the long-term sustainability of monitoring networks.

11.
Front Chem ; 7: 104, 2019.
Article in English | MEDLINE | ID: mdl-30931293

ABSTRACT

There is great economic incentive in developing efficient catalysts to produce hydrogen or syngas by catalytic partial oxidation of methane (CPOM) since this is a much less energy-intensive reaction than the highly endothermic methane steam reforming reaction, which is the prominent reaction in industry. Herein, we report the catalytic behavior of nickel-based catalysts supported on different oxide substrates (Al2O3, CeO2, La2O3, MgO, and ZrO2) synthesized via wet impregnation and solid-state reaction. Furthermore, the impact of Rh doping was investigated. The catalysts have been characterized by X-ray diffraction, N2 adsorptiondesorption at -196°C, temperature-programmed reduction, X-ray photoelectron spectroscopy, O2-pulse chemisorption, transmission electron microscopy, and Raman spectroscopy. Supported Ni catalysts were found to be active for CPOM but can suffer from fast deactivation caused by the formation of carbon deposits as well as via the sintering of Ni nanoparticles (NPs). It has been found that the presence of Rh favors nickel reduction, which leads to an increase in the methane conversion and yield. For both synthesis methods, the catalysts supported on alumina and ceria show the best performance. This could be explained by the higher surface area of the Ni NPs on the alumina surface and presence of oxygen vacancies in the CeO2 lattice, which favor the proportion of oxygen adsorbed on defect sites. The catalysts supported on MgO suffer quick deactivation due to formation of a NiO/MgO solid solution, which is not reducible under the reaction conditions. The low level of carbon formation over the catalysts supported on La2O3 is ascribed to the very high dispersion of the nickel NPs and to the formation of lanthanum oxycarbonate, through which carbon deposits are gasified. The catalytic behavior for catalysts with ZrO2 as support depends on the synthesis method; however, in both cases, the catalysts undergo deactivation by carbon deposits.

12.
Materials (Basel) ; 11(6)2018 Jun 04.
Article in English | MEDLINE | ID: mdl-29867061

ABSTRACT

In this work we report the effects of support structural properties and its modification with some metal oxides modifiers on the catalytic behavior of Au catalysts in the total CO oxidation at 20 °C. Au catalysts were supported on mesoporous silica materials (MSM) having different structural properties: Channel-like (SBA-15), cage-like (SBA-16), hexagonal (HMS), and disordered (DMS-1) structures. The effect of the modifier was evaluated by comparison of the catalytic response of the SBA-15-based catalysts modified with MgO, Fe2O3, TiO2, and CeO2. The chemical, structural, and electronic properties of the catalysts were investigated by a variety of techniques (metal content analysis by ICP-OES, N2 physisorption, XRD, UV-vis DRS, DRIFTS of adsorbed CO and OH regions, oxygen storage capacity (OSC), HR-TEM, and XPS). The activity of calcined catalysts in the CO oxidation reaction were evaluated at steady state conditions, at 20 °C, atmospheric pressure, and when using, as feed, a 1%CO/1%O2/98% gas mixture. The work clearly demonstrated that all Au catalysts supported on the mesoporous silicas modified with metal oxides were more active than the Au/SBA-15 and Au/MgO reference ones. The support structural properties and type of dopant were important factors influencing on the catalyst behavior. Concerning the support textural properties, it was found that the HMS substrate with the wormhole-structure offers better porosity and specific surface area than their silica counterparts having channel-like (SBA-15), cage-like (SBA-16), and disordered (DMS-1) mesoporous structures. Concerning the effect of modifier, the best catalytic response was achieved with the catalysts modified with MgO. After activation by calcination at 200 °C for 4 h, the Au/MgO/HMS catalyst exhibited the best catalytic performance, which was ascribed to the combined effects of the best structural properties, a large support oxygen storage capacity and homogeneous distribution of gold particles on the support (external and inner). Implications of the type of active sites (Au1+ or Au°), support structural properties and role of modifier on the catalytic activity are discussed.

13.
Sci Total Environ ; 631-632: 1590-1599, 2018 Aug 01.
Article in English | MEDLINE | ID: mdl-29727983

ABSTRACT

Although water is involved in many ecosystem services, the absence of monitoring data restricts the development of effective water management strategies especially in remote regions. Traditional monitoring networks can be expensive, with unaffordable costs in many low-income countries. Involving citizens in monitoring through crowdsourcing has the potential to reduce these costs but remains uncommon in hydrology. This study evaluates the quality and quantity of data generated by citizens in a remote Kenyan basin and assesses whether crowdsourcing is a suitable method to overcome data scarcity. We installed thirteen water level gauges equipped with signboards explaining the monitoring process to passers-by. Results were sent via a text-message-based data collection framework that included an immediate feedback to citizens. A public web interface was used to visualize the data. Within the first year, 124 citizens reported 1175 valid measurements. We identified thirteen citizens as active observers providing more than ten measurements, whereas 57% only sent one record. A comparison between the crowdsourced water level data and an automatic gauging station revealed high data quality. The results of this study indicate that citizens can provide water level data of sufficient quality and with high temporal resolution.


Subject(s)
Crowdsourcing , Environmental Monitoring/methods , Water Supply/statistics & numerical data , Hydrology , Kenya
14.
Sci Total Environ ; 624: 769-780, 2018 May 15.
Article in English | MEDLINE | ID: mdl-29272846

ABSTRACT

Studies that quantify nitrous oxide (N2O) fluxes from African tropical forests and adjacent managed land uses are scarce. The expansion of smallholder agriculture and commercial agriculture into the Mau forest, the largest montane forest in Kenya, has caused large-scale land use change over the last decades. We measured annual soil N2O fluxes between August 2015 and July 2016 from natural forests and compared them to the N2O fluxes from land either managed by smallholder farmers for grazing and tea production, or commercial tea and eucalyptus plantations (n=18). Air samples from 5 pooled static chambers were collected between 8:00am and 11:30am and used within each plot to calculate the gas flux rates. Annual soil N2O fluxes ranged between 0.2 and 2.9kgNha-1yr-1 at smallholder sites and 0.6-1.7kgNha-1yr-1 at the commercial agriculture sites, with no difference between land uses (p=0.98 and p=0.18, respectively). There was marked variation within land uses and, in particular, within those managed by smallholder farmers where management was also highly variable. Plots receiving fertilizer applications and those with high densities of livestock showed the highest N2O fluxes (1.6±0.3kgN2O-Nha-1yr-1, n=7) followed by natural forests (1.1±0.1kgN2O-Nha-1yr-1, n=6); although these were not significantly different (p=0.19). Significantly lower fluxes (0.5±0.1kgNha-1yr-1, p<0.01, n=5) were found on plots that received little or no inputs. Daily soil N2O flux rates were not correlated with concurrent measurements of water filled pore space (WFPS), soil temperature or inorganic nitrogen (IN) concentrations. However, IN intensity, a measure of exposure of soil microbes (in both time and magnitude) to IN concentrations was strongly correlated with annual soil N2O fluxes.

15.
J Environ Qual ; 45(5): 1531-1539, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27695760

ABSTRACT

Greenhouse gas (GHG) emission measurements from livestock excreta in Africa are limited. We measured CH and NO emissions from excreta of six Boran () and six Friesian () steers near Nairobi, Kenya. The steers were fed one of three diets (T1 [chaffed wheat straw], T2 [T1 + Meissner - 0.2% live weight per day], and T3 [T1 + calliandra - 0.4% live weight every 2 d]). The T1 diet is similar in quality to typical diets in the region. Calliandra is a leguminous fodder tree promoted as a feed supplement. Fresh feces and urine were applied to grasslands and emissions measured using static chambers. Cumulative 28-d fecal emissions were 302 ± 52.4 and 95 ± 13.8 mg CH-C kg dry matter for Friesen and Boran steers, respectively, and 11.5 ± 4.26 and 24.7 ± 8.32 mg NO-N kg dry matter for Friesian and Boran steers, respectively. For urine from Friesian steers, the NO emissions were 2.8 ± 0.64 mg NO-N 100 mL urine. The CH emission factors (EFs) (246 ± 49.5 and 87 ± 12.7 g CH-C yr animal for Friesan and Boran, respectively) were lower than the International Panel on Climate Change EFs (750 g CH-C animal yr), whereas the NO EFs (0.1 and 0.2% for the Friesian and Boran feces, respectively, and 1.2% for urine) were also lower than International Panel on Climate Change estimates. The low N content of the excreta likely caused the low emissions and indicates that current models probably overestimate CH and NO emissions from African livestock manure.


Subject(s)
Manure , Methane/analysis , Nitrous Oxide/analysis , Animal Feed , Animals , Cattle , Diet , Grassland , Kenya
16.
Molecules ; 21(4): 401, 2016 Mar 24.
Article in English | MEDLINE | ID: mdl-27023502

ABSTRACT

The effect of temperature and water/thiourea ratio on the growth, crystallinity and morphological characteristics of CdS nanostructures synthetized by a solvothermal method using ethylenediamine as solvent were studied. The temperature and water/thiourea ratio used in the synthesis determine the surface area, shape, length and degree of crystallinity of the CdS nanostructures obtained. Nanowires of high crystallinity and length were obtained when the solvothermal synthesis was performed at 190 °C, while nanorods with lower length and crystallinity were obtained as the solvothermal temperature decreased to 120 °C. The change in the water/thiourea ratio affects the crystallinity and length of the CdS nanostructures to a lesser extent than temperature. Nevertheless an increase in the water/thiourea ratio used during the solvothermal synthesis resulted in CdS nanorods with higher crystallinity, lower aspect ratio and lower specific surface area. Textural, structural and surface properties of the prepared CdS nanostructures were determined and related to the activity results in the production of hydrogen from aqueous solutions containing SO3(2-) + S(2-) under visible light.


Subject(s)
Cadmium Compounds/chemistry , Hydrogen/chemistry , Solvents/chemistry , Water/chemistry , Light , Nanotubes/chemistry , Nanowires/chemistry , Photochemistry , Sulfides/chemistry , Surface Properties , Temperature , Thiourea/chemistry
17.
Animal ; 9(7): 1221-9, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25682711

ABSTRACT

Until the turn of the century, farmers in West Africa considered cotton to be the 'white gold' for their livelihoods. Large fluctuations in cotton prices have led farmers to innovate into other business including dairy. Yet the productivity of cows fed traditional diets is very poor, especially during the long dry season. This study combines earlier published results of farmer participatory experiments with simulation modelling to evaluate the lifetime productivity of cows under varying feeding strategies and the resulting economic performance at farm level. We compared the profitability of cotton production to the innovation of dairy. The results show that milk production of the West African Méré breed could be expanded if cows are supplemented and kept stall-fed during the dry season. This option seems to be profitable for better-off farmers, but whether dairy will replace (some of) the role of cotton as the white gold for these smallholder farmers will depend on the cross price elasticity of cotton and milk. Farmers may (partly) replace cotton production for fodder production to produce milk if the price of cotton remains poor (below US$0.35/kg) and the milk price relatively strong (higher than US$0.38/kg). Price ratios need to remain stable over several seasons given the investments required for a change in production strategy. Furthermore, farmers will only seize the opportunity to engage in dairy if marketing infrastructure and milk markets are further developed.


Subject(s)
Animal Feed/analysis , Cattle/physiology , Dairying/economics , Dairying/methods , Milk/chemistry , Models, Theoretical , Animal Feed/economics , Animals , Breeding/methods , Commerce , Cotton Fiber/economics , Farmers , Female , Humans , Mali , Milk/economics
18.
Clin Ophthalmol ; 8: 2045-53, 2014.
Article in English | MEDLINE | ID: mdl-25336904

ABSTRACT

PURPOSE: To evaluate ophthalmologists' opinion of, and use of, micronutritional dietary supplements 10 years after publication of the first Age-Related Eye Disease Study (AREDS) study. METHODS: Participation was solicited from 4,000 European ophthalmologists. Responding physicians were screened, and those treating at least 40 patients with age-related macular degeneration (AMD) per month and prescribing nutrition supplements at least 4 times per month were admitted and completed a 40-item questionnaire. RESULTS: The surveyed sample included 112 general ophthalmologists and 104 retinal specialists. Most nutritional supplements (46%) were initiated when early/intermediate AMD was confirmed, although 18% were initiated on confirmation of neovascular AMD. Clinical studies were well known: 90% were aware of AREDS, with 88% aware of AREDS1 and 36% aware of the, as-yet-unpublished, AREDS2 studies. Respondents considered lutein, zeaxanthin, zinc, omega-3, and vitamins to be the most important components of nutritional supplements, with the results of AREDS2 already having been taken into consideration by many. Ophthalmologists anticipate more scientific studies as well as improved product quality but identify cost as a barrier to wider uptake. CONCLUSION: Micronutrition is now part of the routine management of AMD for many ophthalmologists. Ophthalmologists choosing to use nutritional supplements are well-informed regarding current scientific studies.

19.
Ophthalmologica ; 231(4): 211-20, 2014.
Article in English | MEDLINE | ID: mdl-24662778

ABSTRACT

PURPOSE: To evaluate the long-term progression of myopic maculopathy and functional outcome after treatment of myopic choroidal neovascularization (CNV) with photodynamic therapy (PDT) and/or intravitreal ranibizumab (IVR). METHODS: Retrospective study with a cross-sectional evaluation. Eyes were assigned to 4 groups (PDT, IVR, PDT + IVR, dry myopic maculopathy) and evaluated with best-corrected visual acuity, color fundus photography and spectral-domain optical coherence tomography. Chorioretinal atrophy progression was quantified. RESULTS: Fifty-four eyes were included with a mean follow-up of 80.6 ± 28.0 months. The prevalence of diffuse, patchy and macular atrophy increased during the follow-up, in contrast with tessellated fundus, lacquer cracks and active CNV. Progression of macular atrophy was significant in the 3 treatment groups (p < 0.05) and predictive of visual acuity. It depended on age, degree of myopia and presence of staphyloma, but not on the type of treatment. CONCLUSIONS: The long-term functional outcome of eyes with myopic CNV is more dependent on the progression of macular atrophy, and not on the type of treatment.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Choroidal Neovascularization/drug therapy , Corneal Dystrophies, Hereditary/diagnosis , Myopia, Degenerative/drug therapy , Photochemotherapy , Choroidal Neovascularization/diagnosis , Choroidal Neovascularization/physiopathology , Corneal Dystrophies, Hereditary/physiopathology , Cross-Sectional Studies , Disease Progression , Drug Combinations , Female , Fluorescein Angiography , Humans , Intravitreal Injections , Male , Middle Aged , Myopia, Degenerative/diagnosis , Myopia, Degenerative/physiopathology , Photosensitizing Agents/therapeutic use , Porphyrins/therapeutic use , Ranibizumab , Retrospective Studies , Tomography, Optical Coherence , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Verteporfin , Visual Acuity/physiology
20.
Eur J Ophthalmol ; 23(6): 887-98, 2013.
Article in English | MEDLINE | ID: mdl-23787449

ABSTRACT

PURPOSE: To evaluate choroidal thickness in highly myopic eyes with choroidal neovascularization (CNV), 3 or more years after treatment with photodynamic therapy (PDT), intravitreal ranibizumab (IVR), or both (PDT + IVR). METHODS: The medical records of patients with high myopia and CNV treated with PDT or IVR in our department were reviewed. Eyes meeting the inclusion criteria were assigned to 3 groups: PDT, IVR, and PDT + IVR. A fourth group, "dry myopic maculopathy," included the contralateral highly myopic eyes that never developed CNV. All patients performed a cross-sectional evaluation with best-corrected visual acuity (BCVA), measurement of axial length, color fundus photography, and enhanced depth imaging with spectral domain optical coherence tomography. RESULTS: Forty-two eyes (21 patients) were included: 11 eyes (26.2%) in the PDT group, 8 (19.0%) in the IVR group, 9 (21.4%) in the PDT + IVR group, and 14 (33.3%) in the dry maculopathy group. Subfoveal choroidal thickness showed no significant differences between groups (p>0.05). Positive correlation was found between BCVA and macular choroidal thickness (r = +0.293, p<0.001). Regression analysis showed that age (p<0.001), axial length (p<0.001), sex (p = 0.001), and myopic lesions such as tessellated fundus (p = 0.046) and patchy atrophy (p = 0.008) were predictive of choroidal thickness. Type of treatment was not predictive of choroidal thickness. CONCLUSIONS: Older age and greater axial length are the major factors associated with macular choroidal thinning in highly myopic eyes submitted to CNV treatment. The type of treatment performed for myopic CNV had no predictive contribution for choroidal thickness.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Choroid/pathology , Choroidal Neovascularization/drug therapy , Myopia, Degenerative/drug therapy , Photochemotherapy , Adult , Age Factors , Aged , Aged, 80 and over , Axial Length, Eye/pathology , Choroidal Neovascularization/physiopathology , Cross-Sectional Studies , Female , Fluorescein Angiography , Humans , Male , Middle Aged , Myopia, Degenerative/physiopathology , Organ Size , Ranibizumab , Retrospective Studies , Tomography, Optical Coherence , Visual Acuity/physiology
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