The Quality-Quantity Trade-off in the Principal-Agent Framework

This paper uses the principal-agent theory to analytically investigate the optimal incentive-based compensation contract that a processor should offer to a grower performing efforts in quantity and quality. In this process, we contribute to the substantive literature on multi-task principal-agent models by analyzing the quality-quantity trade-off and studying the implications of such a relationship in the principal-agent framework. One striking result of these effects is that, under appropriate incentive-based grower’s compensation, the processor may encourage grower’s effort in quality without crowding out grower’s effort in quantity.quality, quantity, trade-off, incentive contract, principal-agent framework, uncertainty, Agribusiness, Agricultural and Food Policy, D86,

Investing cash transfers to raise long term living standards

The authors test whether poor households use cash transfers to invest in income generating activities that they otherwise would not have been able to do. Using data from a controlled randomized experiment, they find that transfers from the Oportunidades program to households in rural Mexico resulted in increased investment in micro-enterprise and agricultural activities. For each peso transferred, beneficiary households used 88 cents to purchase consumption goods and services, and invested the rest. The investments improved the household's ability to generate income with an estimated rate of return of 17.55 percent, suggesting that these households were both liquidity and credit constrained. By investing transfers to raise income, beneficiary households were able to increase their consumption by 34 percent after five and a half years in the program. The results suggest that cash transfers to the poor may raise long-term living standards, which are maintained after program benefits end.Economic Theory&Research,Small Area Estimation Poverty Mapping,Municipal Housing and Land,Land and Real Estate Development,Real Estate Development

Neuronal Mitophagy in Neurodegenerative Diseases

Neuronal homeostasis depends on the proper functioning of different quality control systems. All intracellular components are subjected to continuous turnover through the coordinated synthesis, degradation and recycling of their constituent elements. Autophagy is the catabolic mechanism by which intracellular cytosolic components, including proteins, organelles, aggregates and any other intracellular materials, are delivered to lysosomes for degradation. Among the different types of selective autophagy described to date, the process of mitophagy involves the selective autophagic degradation of mitochondria. In this way, mitophagy is responsible for basal mitochondrial turnover, but can also be induced under certain physiological or pathogenic conditions to eliminate unwanted or damaged mitochondria. Dysfunctional cellular proteolytic systems have been linked extensively to neurodegenerative diseases (ND) like Alzheimer's disease (AD), Parkinson's disease (PD), or Huntington's disease (HD), with autophagic failure being one of the main factors contributing to neuronal cell death in these diseases. Neurons are particularly vulnerable to autophagic impairment as well as to mitochondrial dysfunction, due mostly to their particular high energy dependence and to their post-mitotic nature. The accurate and proper degradation of dysfunctional mitochondria by mitophagy is essential for maintaining control over mitochondrial quality and quantity in neurons. In this report, I will review the role of mitophagy in neuronal homeostasis and the consequences of its dysfunction in ND

Synthesis and structural studies of a dimeric bis(oxamate) copper(II) complex

A new series of a dimeric bis(oxamato) copper(II) complex of formula M4[Cu(oeo)]2 (where Et2H2(oeo) is diethyl ethylene-1,2-dioxamate and M = alkali metal) is described. The complex is formed by two copper(II) atoms and two ligand molecules of which each oxamato group is coordinating towards two different copper(II) ions leading to a distorted square planar environment. Due to the trans-bis(N,O) arrangement around the copper(II) ion, the dimer displays a helicoidal structure. We present here detailed structural studies of this complex with a number of counter ions. Many polymorphs and hydrates are observed and their synthesis and structures are described. A sequential strategy has been developed in which starting from the ligand precursor, Et2H2oeo, the addition of alkali metal hydroxides affords the hydrolysis of the ester leading to the formation of the salt of the ester, M2H2oeo. Then, transmetallation of the alkali metal salt is carried out with the addition of a copper(II) salt. The dimeric copper(II) complex, M4[Cu(oeo)]2, is finally achieved with the addition of the corresponding alkali metal hydroxide. Structural studies of the intermediate compounds are also described. The partial occupancy in the copper(II) site is a common feature in M4[Cu(oeo)]2. Surprisingly, the copper(II) site can be left vacant and the compound still remain with the same helicoidal structure as the non-coordinated ligand, when the amide is protonated, adopting a structurally similar H-bond arrangement. A wide range of copper(II) occupancies have been observed in the different obtained compounds: from compounds with a fully occupied site to compounds with only 10% of copper(II)present in the complex . These differences in the amount of copper(II) present in the complex has consequences in its packing in the crystal structure. The synthesis and characterisation of the copper(II) complex using tetrabutylammonium hydroxide as the counterion is also reported. As a result of the bulky nature of the cation, the mononuclear structure is observed, (n-Bu4N)4[Cu(oeoH)2]. Initial transmetallation reactions are reported with Co(II), in which partial and complete exchange from Cu(II) is observed

Detection and characterization of Huntingtin-protein interactions using resonance energy transfer methodologies

HTT ist ein Protein, das durch seine Verbindung mit mehreren Interaktionspartnern an einer Vielzahl von zellulären Prozessen beteiligt ist. Darüber hinaus verursacht eine Mutation im HTT-Gen eine Krankheit, die als Huntington-Krankheit (HD) bezeichnet wird. Aufgrund der gerüstbildenden Eigenschaften von HTT wurde eine Vielzahl von Studien durchgeführt, um potenzielle therapeutische Ziele zu identifizieren. Die auf dem Resonanzenergietransfer (RET) basierenden Ansätze sind jedoch im Bereich der Huntington-Krankheit noch nicht vollständig genutzt worden. Daher habe ich versucht, solche Ansätze in Interaktionsstudien mit dem HTT-Exon 1 (HTTexon1) und dem Protein in voller Länge zu bewerten. Ich habe eine Benchmarking-Studie mit einem zuvor beschriebenen Huntingtin-interagierenden Protein (HIP) und HTTex1 (Wildtyp und mutiert) unter Verwendung eines BRET-Ansatzes durchgeführt. Meine Studien bestätigten die binäre Interaktion zwischen HTTex1 und sieben Proteinen. Ich habe auch drei Interaktionen mit der mutierten Version von HTTex1 bestätigt. Zusätzlich bewertete ich die Interaktionen durch FRET-Messungen mit Hilfe der Durchflusszytometrie. Der zweite Teil dieser Arbeit zielte darauf ab, ein Hochdurchsatz-Screening für den Nachweis von Protein-Protein-Interaktionen (PPIs) mit HTT in voller Länge (FL) unter Verwendung von Biolumineszenz-Resonanz-Energie-Transfer zu etablieren. Auf diese Weise konnte ich die Wechselwirkung zwischen FL HTT und einer Bibliothek von 580 Proteinkinasen bewerten. Schließlich analysierte ich die Spezifität der entdeckten Wechselwirkungen, indem ich die unspezifische Bindung durch Donor-Sättigungstests bewertete. Zusammenfassend belegen meine Ergebnisse die potenzielle Verwendung von Resonanzenergietransferansätzen zur Validierung von HTT-Wechselwirkungen. Außerdem wird ein neues Screening-Tool vorgestellt, das dazu beitragen soll, HTT-Interaktoren zu identifizieren und zu verifizieren.HTT is a protein involved in a plethora of cellular processes through its association with several interaction partners. Furthermore, a mutation in the HTT gene, causes a disease denominated Huntington’s disease (HD). Due to the scaffolding properties of HTT, a large variety of studies have been performed to identify potential therapeutical targets. However, resonance energy transfer-based (RET) approaches have not been fully exploited in the HD field. Therefore, I aimed to evaluate such approaches in interaction studies using the HTT exon 1 (HTTexon1) as well as the full-length protein. I performed a benchmarking study with a previously described huntingtin interacting protein (HIP) and HTTex1 (wild type and mutated) using a BRET approach. My studies confirmed the binary interaction between HTTex1 and seven proteins. I also confirmed three interactions with the mutated version of HTTex1. Additionally, I also evaluated the interactions by measuring FRET using flow cytometry. The second part of this work aimed to stablish a high-throughput screening for the detection of protein-protein interactions (PPIs) with full-length (FL) HTT using bioluminescence resonance energy transfer. With this, I was able to evaluate the interaction between FL HTT and a library composed by 580 protein kinases. Finally, I analysed the specificity of the detected interactions by assessing unspecific binding through donor saturation assays. In summary my results provide evidence of the potential use of resonance energy transfer approaches to validate HTT interactions. Additionally, a new screening tool is presented to contribute to identify and verify HTT interactors

The yield/quality trade-off and contractual choice

This paper provides an analysis of the choice of governance mechanism in agriculture using an integrated perspective based on agency theory. The main ways of organizing agriculture are compared: spot market and incentive contract. With the analytical development of both models, it is explored that the choice of the optimal mechanism depends on initial conditions such as uncertainty, the risk aversion of the agents or the number of competitors. Moreover, according to the predictions made by the economic literature on agrarian organization, the results support the coexistence of both governance alternatives.Crop Production/Industries,

Quality and governance mode choice: a transaction cost approach to the wine industry

We analyze the relationship between product quality and governance mode choice using the results of a survey of DOC Rioja wineries. Wineries that produce high-quality wines are more likely to vertically integrate than are wineries that produce low-quality wines. Consistent with Transaction Cost Economics, we find evidence that asset specificity and uncertainty are important determinants of vertical integration. Finally, the size of the winery is also an important factor that affects governance mode choice in viticulture.quality, governance mode choice, transaction cost, Industrial Organization,

Double Sided Moral Hazard and Share Contracts in agriculture

This paper develops a double-sided moral hazard model of share contract in agriculture, with imperfect quality measurement by the agent and the principal, who contribute to the final good quality in terms of production effort and marketing effort respectively. Using this model, we analyse the implications of the share contract for quantity and quality, often ignored in previous analysis. With the help of a simulation exercise, we prove that the outcome-conditioned share generally weakens the agent´s incentive to make effort in quality input. This finding could explain the contractual evidence in some differentiated markets such as the wine market, where bottle-price conditioned contracts are rarely used.share-contract, double moral-hazard, quality, Farm Management,

On the co-existence of spot and contract markets: an analysis of quality

The possible co-existence of spot and contract market that can emerge in the presence of quality issues with a number of growers and processors in each stage is something that has largely remained an open question in the literature. This paper is an attempt to fill this void. We use a straightforward two-stage Cournot oligopoly model with specific demand and cost functions. In the first stage, processors decide simultaneously whether or not to set an incentive contract. The second stage is the stage in which growers choose their levels of quantity and quality based on the industry structure developed in the first stage. With the help of numerical simulations we conducted the study of the equilibrium structures. Our results suggest that for a wide range of number of participants in both markets, participation in both markets constitutes a Nash equilibrium for the model.Marketing,

Why Does Alejandro Know More about Politics than Catalina? Explaining the Latin American Gender Gap in Political Knowledge

This article tests contextual and individual-level explanations of the gender gap in political knowledge in Latin American countries. It suggests that this gap is impacted by political and economic settings through two interrelated mechanisms: gender accessibility (that is, the extent of available opportunities for women to influence the political agenda) and gender-bias signaling (that is, the extent to which women play important roles in the public sphere). Analyzing data from the 2008 Americas Barometer survey, this study shows that the gender gap in political knowledge is smaller among highly educated citizens, in rural areas (where both men and women know little about politics) and in bigger cities (where women’s levels of political knowledge are higher). More importantly, the magnitude of the gap varies greatly across countries. Gender differences in income, party system institutionalization and the representation of women in national parliaments are all found to play a particularly important role in explaining the magnitude of the gender gap in political knowledge across Latin America