A high-altitude peatland record of environmental changes in the NW Argentine Andes (24 ° S) over the last 2100 years

High-altitude cushion peatlands are versatile archives for high-resolution palaeoenvironmental studies, due to their high accumulation rates, range of proxies, and sensitivity to climatic and/or human-induced changes. Especially within the Central Andes, the knowledge about climate conditions during the Holocene is limited. In this study, we present the environmental and climatic history for the last 2100 years of Cerro Tuzgle peatland (CTP), located in the dry Puna of NW Argentina, based on a multi-proxy approach. X-ray fluorescence (XRF), stable isotope and element content analyses (δ13C, δ15N, TN and TOC) were conducted to analyse the inorganic geochemistry throughout the sequence, revealing changes in the peatlands' past redox conditions. Pollen assemblages give an insight into substantial environmental changes on a regional scale. The palaeoclimate varied significantly during the last 2100 years. The results reflect prominent late Holocene climate anomalies and provide evidence that in situ moisture changes were coupled to the migration of the Intertropical Convergence Zone (ITCZ). A period of sustained dry conditions prevailed from around 150 BC to around AD 150. A more humid phase dominated between AD 200 and AD 550. Afterwards, the climate was characterised by changes between drier and wetter conditions, with droughts at around AD 650-800 and AD 1000-1100. Volcanic forcing at the beginning of the 19th century (1815 Tambora eruption) seems to have had an impact on climatic settings in the Central Andes. In the past, the peatland recovered from climatic perturbations. Today, CTP is heavily degraded by human interventions, and the peat deposit is becoming increasingly susceptible to erosion and incision.Fil: Schittek, Karsten. University of Heidelberg; Alemania. Universitat Zu Köln; AlemaniaFil: Kock, Sebastian T.. University of Heidelberg; Alemania. Research Center Jülich; AlemaniaFil: Lücke, Andreas. Helmholtz Gemeinschaft. Forschungszentrum Jülich; AlemaniaFil: Hense, Jonathan. Universitaet Bonn; AlemaniaFil: Ohlendorf, Christian. Universitat Bremen; AlemaniaFil: Kulemeyer, Julio José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Jujuy. Universidad Nacional de Jujuy. Centro de Investigaciones y Transferencia de Jujuy; ArgentinaFil: Lupo, Liliana Concepcion. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Jujuy. Universidad Nacional de Jujuy. Centro de Investigaciones y Transferencia de Jujuy; ArgentinaFil: Schäbitz, Frank. Universitat Zu Köln; Alemani

Vegetable Purchase Patterns of Consumers in Davao City and Cagayan de Oro City, Philippines

The goal to increase farm productivity, attain food security and safety, and alleviate poverty among smallholder farmers has urged government and nongovernment organizations in the Philippines to develop and promote organic and safe vegetables. While these products are healthier and safer, previous studies have proven that these are more expensive than their conventional counterparts. A mall intercept using a structured questionnaire was conducted to survey 240 respondents in Davao City and 110 respondents in Cagayan de Oro City (CDO) in Southern Philippines. This is a qualitative research that aims to provide information about the current vegetable purchase patterns of consumers in both study areas and to identify its implications and opportunities for organic and safe vegetable producers. Results show that more than 50% of the respondents in both cities purchase vegetables in wet markets and supermarkets on a weekly basis. In terms of expenditure on vegetables, 85% of the respondents in CDO and 74% of the respondents in Davao City have expenditure on vegetables of at most PhP500 per week. The majority of consumers in both cities buy vegetables mostly from wet markets because vegetables are sold at a lower price, are fresher, and there is wider product assortment. Consumers in Davao City and CDO buy vegetables from supermarkets because of convenience and cleanliness, respectively. They purchase mostly tomatoes, eggplants, and cabbages. Based on previous studies, these vegetable purchase patterns of consumers have not changed for over ten years. Thus, this challenges organic and safe vegetable producers, as well as other vegetable industry stakeholders, to produce cheap but high-quality vegetables

Limits, Transparency, and Board Independence Against Tax Avoidance

Taxes are levied by the government primarily for public service purposes (De Leon & De Leon, 2016).However, the high tax rates and narrow tax base imposed in the Philippines become burdensome for taxpayers and also decrease total government revenue collections (Diokno, 2008). It is shown in this study that foreign ownership and customer concentration both increase the levels of corporate tax avoidance practiced by firms while board independence decreases the same. Hence, we do not support the government’s plan to ease foreign ownership restrictions through the amendment of the Constitution (Romualdez, 2017) because easing the current restrictions may entail decreased government revenue. Additionally, we recommend that the International Accounting Standards Board (IASB) strengthen the enforcement of the International Financial Reporting Standards 8 (IFRS 8). In this case, increased transparency in disclosures is needed to help the government prevent the use of tax havens by major conglomerates. Lastly, we support the Securities and Exchange Commission’s (SEC) recommendation to have a certain minimum threshold on the proportion of independent directors in PSElisted firms on the basis that doing so will reduce levels of tax avoidance within these firms

Combining Experiment and Theory to Elucidate the Role of Supercritical Water in Sulfide Decomposition

The cleavage of C–S linkages plays a key role in fuel processing and organic geochemistry. Water is known to affect these processes, and several hypotheses have been proposed, but the mechanism has been elusive. Here we use both experiment and theory to demonstrate that supercritical water reacts with intermediates formed during alkyl sulfide decomposition. During hexyl sulfide decomposition in supercritical water, pentane and CO + CO2 were detected in addition to the expected six carbon products. A multi-step reaction sequence for hexyl sulfide reacting with supercritical water is proposed which explains the surprising products, and quantum chemical calculations provide quantitative rates that support the proposed mechanism. The key sequence is cleavage of one C–S bond to form a thioaldehyde via radical reactions, followed by a pericyclic addition of water to the CS bond to form a geminal mercaptoalcohol. The mercaptoalcohol decomposes into an aldehyde and H2S either directly or via a water-catalyzed 6-membered ring transition state. The aldehyde quickly decomposes into CO plus pentane by radical reactions. The time is ripe for quantitative modelling of organosulfur reaction kinetics based on modern quantum chemistry

Food Safety Concerns of Vegetable Consumers in Davao City, Philippines

Food safety has become a growing concern among vegetable consumers. Studies have shown changes in the purchasing pattern of consumers due to food safety concerns. In developed countries, food quality and safety have become increasingly important attributes being considered due to food-borne diseases. In this paper, we determined the consumers’ level of food safety concern at various stages along the vegetable value chain and analyzed how it affects their purchase patterns. We conducted a mall intercept survey among 240 respondents at two supermarkets in Davao City, Philippines, using a structured questionnaire and organized focus group discussions (FGDs) to triangulate our findings. Slovin’s formula was used to determine the sample size. Results showed that most of the consumers were extremely concerned with the amount of chemicals used in vegetable production, cleanliness of storage conditions, retail and entire market outlet, disposal of waste vegetables, quality of vegetables used in presliced packs, and quality of water used in washing vegetables. Ironically, despite their high level of concern on food safety, particularly on chemical residues, most of the respondents always purchase conventional vegetables and never purchase certified organic vegetables. This can be attributed to the wide price difference of certified organic and conventional vegetables. Based on FGD results, consumers emphasized the importance of certification as an assurance of safety. However, consumers demand that food quality and safety assurance should be delivered at a reasonable price. The challenge for stakeholders in the vegetable supply chains is to reduce the cost of certification while ensuring food safety and traceability along the chain

Willingness to Pay for Certified Safe Vegetables in Davao City, Philippines

Safe vegetable production is being practiced in the Philippines to address food safety concerns on vegetables. In this study, we assessed the viability of producing and marketing certified safe vegetables in Davao City by estimating consumers’ willingness to pay (WTP) for certified safe vegetables and analyzing the factors affecting it. The determinants of the consumer decision whether to purchase certified safe vegetables and WTP for certified safe vegetables were analyzed using logistic and Tobit regression, respectively. We found that most consumers in Davao City are willing to purchase (ranging from 82% to 91%) certified safe vegetables. The factors that significantly affect the likelihood of a consumer to purchase certified safe vegetables at the wet market are civil status, educational attainment, and frequency of purchase and the factors that significantly affect the likelihood of a consumer to purchase certified safe vegetables at the supermarket are gender and vegetable expense. On the average, Davao City consumers are willing to pay an additional PhP6.00/kg and PhP5.50/kg on top of the regular retail price for certified safe vegetables sold at the wet market and supermarket, respectively. These findings imply that there is a market for certified safe vegetables in Davao City as indicated by the consumers’ willingness to purchase and willingness to pay. However, it should be noted that these consumers are willing to pay only a small premium above regular retail prices. Vegetable farmers and marketers can capitalize on this opportunity, but the cost of producing and marketing certified safe vegetables must not exceed its potential benefits

Bisabolane type sesquiterpenes from a marine Didiscus sponge

Two bisabolane type sesquiterpene phenols, (+)-curcuphenol (1) and (+)-curcudiol (2), were isolated from a Philippine marine sponge, Didiscus sp., in addition to b -sitosterol (3) and phenethylamine (4). The structures of the metabolites were established on the basis of spectral evidence (1D- and 2D NMR, [a]D, EIMS). (+)-Curcuphenol (1) showed cytotoxicity, which is indicative of a p53 independent mechanism

The Roles of Vegetable Value Chain Actors in the Changing Agri-food System: The Case of Davao City, Philippines

Several studies have shown that the retail food industry has been expanding and that consumers have changed their purchase patterns and preferences over time. These challenge vegetable value chain actors to respond to such trends. Hence, this study seeks to examine how players in the chain respond to the changes in the agri-food system, document the changes in the roles of vegetable value chain actors, and identify implications for smallholder producers. One to three interviews were conducted for each of the 15 types of vegetable value chain actors in Davao City, Southern Philippines, which totals 37 key informant interviews. The respondents were asked regarding vegetable industry trends, their roles and functions, their volume and quality requirements, and their willingness to source directly from farmer groups. A survey was also conducted among 60 vegetable farmers in Davao City to assess their roles in the chain. Farmers’ socio-demographic profiles and production and marketing practices were gathered. This study reveals that the layers in the chains have reduced because wholesalers have started to perform forward integration by producing vegetables, moving closer to the production sites, financing vegetable production to establish a strong supply base, and strengthening relationship with suppliers and buyers. Smallholder producers, on the other hand, remain to be heavily dependent on financiers. There are, however, opportunities for smallholder producers, such as organizing themselves into groups to market collectively, share risks, and take advantage of economies of scale and improving production to ensure that they produce better quality vegetables and become more competitive

Fe speciation in Iron modified natural zeolites as sustainable environmental catalysts

Natural purified mordenite from Palmarito de Cauto (ZP) deposit, Cuba, was subjected to a hydrothermal ion exchange process in acid medium with Fe2+ or Fe3+ salts (Fe2+ZP and Fe3+ZP). The set of samples was characterized regarding their textural properties, morphology, and crystallinity, and tested in the NO reduction with CO/C3H6. Infrared spectroscopy coupled with NO as a probe molecule was used to give a qualitative description of the Fe species’ nature and distribution. The exchange process caused an increase in the iron loading of the samples and a redistribution, resulting in more dispersed Fe2+ and Fe3+ species. When contacted with the NO probe, Fe2+ZP showed the highest intensity of nitrosyl bands, assigned to NO adducts on isolated/highly dispersed Fe2+/Fe3+ extra-framework sites and FexOy clusters. This sample is also characterized by the highest NO sorption capacity and activity in NO reduction. Fe3+ZP showed a higher intensity of nitrosonium (NO+) species, without a correlation to NO storage and conversion, pointing to the reactivity of small FexOy aggregates in providing oxygen atoms for the NO to NO+ reaction. The same sites are proposed to be responsible for the higher production of CO2 observed on this sample, and thus to be detrimental to the activity in NO SCR