275 research outputs found
Inter-temporal and Spatial Price Dispersion Patterns and the Well-Being of Maize Producers in Southern Tanzania
We revisit a methodology to gauge the short-term effect of price changes on smallholder farmer's welfare that is popular amongst policy makers and academia. Realising that farmers face substantial seasonal price volatility over the course of an agricultural year, we pay particular attention to the timing of sales and purchases. In addition we depart from the implicit assumption that all farmers scattered across rural areas face the same prices when interacting with markets. Using maize marketing during the 2007–2008 agricultural season in a sample of smallholders in Tanzania as an illustration, we find that especially poor farmers face greater losses than what a standard analysis would suggest. We also relate our methodology to factors that are likely to affect potential benefits or costs from inter-temporal and spatial price dispersion, such as means of transport, access to price information and credit
Road expansion and market integration in the Austrian low countries during the second half of the 18th century.
We analyse the integration of wheat markets across 18 towns in the Austrian Low Countries during the second half of the 18th century and the relationship with the rapidly expanding paved road network in this period. We use a switching regression approach (threshold cointegration) to study long-run and short-run integration of these markets, using monthly wheat prices. We find that throughout this period, markets were spatially interconnected. However, price margins adjust only slowly to long-term levels in response to local shocks. We also find that transaction costs are relatively high. The results suggest a complex market with regular trade flow reversals and periods of unprofitable trade between key markets. It is widely accepted in Belgian historiography that the construction of a paved road network caused a substantial reduction in transaction costs. Our research, however, indicates that distance, fixed costs or links by rivers and canals mainly influenced transaction costs, not the expansion of a paved road network. Two factors can account for this. First, the toll structure on paved roads discouraged bulk trade. Secondly, new private investment in inter-city grain trade that may have led to cuts in the trading costs, typically appeared to be absent in this period. However, adjustment speeds in markets are significantly affected by the existence of paved roads. Better communication and faster transport due to the road network resulted in faster arbitrageCountry; Integration; Market; Market integration;
European Journal of Combinatorics Index, Volume 27
BACKGROUND: Diabetes is an inflammatory condition associated with iron abnormalities and increased oxidative damage. We aimed to investigate how diabetes affects the interrelationships between these pathogenic mechanisms. METHODS: Glycaemic control, serum iron, proteins involved in iron homeostasis, global antioxidant capacity and levels of antioxidants and peroxidation products were measured in 39 type 1 and 67 type 2 diabetic patients and 100 control subjects. RESULTS: Although serum iron was lower in diabetes, serum ferritin was elevated in type 2 diabetes (p = 0.02). This increase was not related to inflammation (C-reactive protein) but inversely correlated with soluble transferrin receptors (r = - 0.38, p = 0.002). Haptoglobin was higher in both type 1 and type 2 diabetes (p < 0.001) and haemopexin was higher in type 2 diabetes (p < 0.001). The relation between C-reactive protein and haemopexin was lost in type 2 diabetes (r = 0.15, p = 0.27 vs r = 0.63, p < 0.001 in type 1 diabetes and r = 0.36, p = 0.001 in controls). Haemopexin levels were independently determined by triacylglycerol (R(2) = 0.43) and the diabetic state (R(2) = 0.13). Regarding oxidative stress status, lower antioxidant concentrations were found for retinol and uric acid in type 1 diabetes, alpha-tocopherol and ascorbate in type 2 diabetes and protein thiols in both types. These decreases were partially explained by metabolic-, inflammatory- and iron alterations. An additional independent effect of the diabetic state on the oxidative stress status could be identified (R(2) = 0.5-0.14). CONCLUSIONS: Circulating proteins, body iron stores, inflammation, oxidative stress and their interrelationships are abnormal in patients with diabetes and differ between type 1 and type 2 diabetes</p
Stimulating agricultural technology adoption lessons from fertilizer use among Ugandan potato farmers
In the context of a growing population in an already densely populated area, agricultural yields will need to increase without putting additional stress on the environment. The adoption of modern inputs by smallholders is an important ingredient of agricultural transformation. In this study we explore plot-level, household-level, and institutional-level characteristics associated with agricultural technology adoption behavior among smallholder farmers. The aim is to uncover correlations that can guide the design of policies and incentives that are likely to increase adoption. We explicitly differentiate between fixed costs that are likely to affect the decision to use the technology and variable costs that are more relevant for the decision regarding use intensity. In addition, we examine how the importance of each of these characteristics differs with asset status. To do so, we use data from about 1,880 potato plots cultivated by 500 randomly selected potato growers in southwestern Uganda. We first categorize households into poorly endowed and well-endowed asset classes based on their access to productive assets. We then estimate double-hurdle models for take-up and use intensity of fertilizer for each group. The results show that the factors associated with the decision to use fertilizer are often different from those associated with the decision about how much fertilizer to use and that the characteristics correlated with fertilizer adoption differ between asset-poor and asset-rich farmers. For instance, asset-poor female-headed households are less likely to use fertilizer, but if they do, they use more of it than male-headed households. Our results also suggest fertilizer packaging and distribution are important factors in fertilizer adoption decisions due to their impact on costs related to both indivisibilities and uncertainty about the quality. We derive a range of policy recommendations
Agricultural extension messages using video on portable devices increase knowledge about seed selection, storage and handling among smallholder potato farmers in southwestern Uganda
Open Access JournalTo feed a growing population, agricultural productivity needs to increase dramatically. Agricultural extension information, with its public, non-rival nature, is generally undersupplied, and public provision remains challenging. In this study, simple agricultural extension video messages, delivered through Android tablets, were tested in the field to determine if they increased farmers’ knowledge of recommended practices on (i) potato seed selection and (ii) seed storage and handling among a sample of potato farmers in southwestern Uganda. Using a field experiment with ex ante matching in a factorial design, it was established that showing agricultural extension videos significantly increased farmers’ knowledge. However, results suggested impact pathways that went beyond simply replicating what was shown in the video. Video messages may have triggered a process of abstraction, whereby farmers applied insights gained in one context to a different context
Expanded-beam through-substrate coupling interface for alignment tolerant packaging of silicon photonics
We demonstrate an alignment tolerant through-substrate coupling interface by combining an optimized downward-directionality grating on a silicon photonic chip with a hybrid integrated polymer lens, generating a collimated beam at lambda = 1310nm for more than 600 mu m
Low-power, low-penalty, flip-chip integrated, 10Gb/s ring-based 1V CMOS photonics transmitter
Modulation with 7.5dB transmitter penalty is demonstrated from a novel 1.5Vpp differential CMOS driver flip-chip integrated with a Si ring modulator, consuming 350fJ/bit from a single 1V supply at bit rates up to 10Gb/s
III-V on silicon DFB laser arrays
We will present our work on epitaxially grown III-V on silicon DFB laser arrays, including results of pure InP-based lasers emitting around 900nm and InGaAs-on-InP lasers emitting around 1300nm
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