bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel risk score to predict early and late recurrence in solitary fibrous tumour
Authors: Georgiesh Tatiana , Boye Kjetil , Bjerkehagen Bodil 
Published: January 2020

AimsSolitary fibrous tumours (SFTs) are rare mesenchymal neoplasms with recurrence rates of 10–30%. Current risk stratification systems for extrameningeal SFTs are based on cohorts with limited follow‐up and are not suitable for prediction of late recurrences. In this study we aimed to develop a prognostic model accounting for both early and late recurrences using a relatively large patient cohort with long‐term follow‐up.Methods and resultsClinicopathological factors were analysed in a cohort of 100 extrameningeal, STAT6‐positive SFTs. Median follow‐up for overall survival (OS) and recurrence‐free interval (RFi) were 121 and 84 months, respectively. Disease relapse occurred in 31% of patients and median time to recurrence was 63 months. In univariate analysis mitotic count, necrosis, male gender and presence of severe atypia and pleomorphism were associated with inferior RFi. Mitotic count, necrosis and male gender were independent predictors of recurrence in multivariate analysis. Previously published risk models were also statistically associated with RFi in our cohort, but failed to reliably identify low‐risk patients due to poor prediction of late recurrences. A novel risk score based on mitotic count, necrosis and gender was able to stratify patients into low‐, intermediate‐ and high‐risk groups for both early and late recurrences.ConclusionsIn this cohort of patients with extrameningeal SFT and long‐term follow‐up mitotic count, necrosis and gender were independent prognostic markers of recurrence. We propose a novel risk score based on these factors and accounting for late recurrences, which should be validated in external cohorts with sufficient follow‐up time.
Hyponatraemia aggravates cardiac susceptibility to ischaemia/reperfusion injury
Authors: Oniki Takahiro , Teshima Yasushi , Nishio Satoru , Ishii Yumi , Kira Shintaro , Abe Ichitaro , Yufu Kunio , Takahashi Naohiko 
Published: January 2020

SummaryHyponatraemia is defined as a serum sodium concentration of <135 mEql/L and is the most common electrolyte disturbance in patients with chronic heart failure. We hypothesize that hyponatraemia may induce Ca2+ overload and enhance reactive oxygen species (ROS) production, which will exacerbate myocardial injury more than normonatraemia. We investigated the effect of hyponatraemia on the ability of the heart to recover from ischaemia/reperfusion episodes. Cardiomyocytes were obtained from 1‐ to 3‐day‐old Sprague Dawley rats. After isolation, cardiomyocytes were placed in Dulbecco's modified Eagle's medium (DMEM) containing low sodium concentration (110, 120, or 130 mEq/L) or normal sodium concentration (140 mEq/L) for 72 hours. Exposure of cardiomyocytes to each of the low‐sodium medium significantly increased both ROS and intracellular Ca2+ levels compared with the exposure to the normal‐sodium medium. In vivo, 8‐week‐old male Sprague Dawley rats were divided into four groups: control group (Con), furosemide group (Fur), low‐sodium diet group (Lsd) and both furosemide and low‐sodium diet group (Fur + Lsd). The hearts subjected to global ischaemia exhibited considerable decrease in left ventricular developed pressure during reperfusion, and the size of infarcts induced by ischaemia/reperfusion significantly increased in the Fur, Lsd and Fur + Lsd compared with that in the Con. Hyponatraemia aggravates cardiac susceptibility to ischaemia/reperfusion injury by Ca2+ overload and increasing in ROS levels.
A theory of heterogeneous city growth
Authors: Ghiglino Christian , Nishimura Kazuo , Venditti Alain 
Published: January 2020

AbstractWe consider an economy with three cities producing different outputs. Two cities produce intermediate goods, a type 1 city producing an intermediate “agricultural” good with capital and labor only, and a type 2 city producing an intermediate “industrial” good with capital, labor, and human capital. A type 3 city produces the final good which is obtained from the two intermediate goods and labor. The asymmetric introduction of human capital allows us to prove that the three cities experience, at equilibrium, heterogeneous endogenous growth rates which are proportional to the growth rate of human capital. We show that the “industrial” type 2 city is characterized by the larger growth rate while the “agricultural” type 1 city experiences the lower growth rate, and thus the type 3 city is characterized by a growth rate which is a convex combination of the two former growth rates. This implies that the relative size in terms of output of the “agricultural” city decreases over time. This property allows us to recover the empirical fact that most non‐agricultural production occurs in growing metropolitan areas. But, simultaneously, as we prove that total labor employed in each city is proportional to the total population, the relative population size distribution of cities is constant over time, as shown in empirical studies.
Comparison of the effects of oral iron treatment every day and every other day in female patients with iron deficiency anaemia
Authors: Düzen Oflas Nur , Demircioğlu Sinan , Yıldırım Doğan Narin , Eker Elife , Kutlucan Ali , Doğan Ali , Aslan Mehmet , Demir Cengiz 
Published: January 2020

AbstractBackgroundIt is known that daily divided doses and high doses of iron increase hepcidin and reduce iron absorption.AimTo compare treatments of iron replacement every other day at low doses, once a day and twice a day in terms of their effectiveness and frequencies of side‐effects.MethodsFor 1 month, Group I received 270 mg ferrous sulphate twice a day (total elemental iron dose: 160 mg/day), Group II received 270 mg ferrous sulphate once a day (total elemental iron dose: 80 mg/day), and Group III received 270 mg ferrous sulphate every other day (total elemental iron dose: 80 mg/every other day). Intragroup and intergroup statistical analyses were carried out.ResultsHaemoglobin (Hb) increased significantly in all three groups (P = 0.00). The increase in Hb levels was similar among the groups (P = 0.09). Ferritin significantly increased in all three groups after the treatment (P = 0.00). The increase in ferritin in Group I was significantly higher than those in Groups II and III (P < 0.05). Gastrointestinal tract (GIS) side‐effects were also significantly higher in Group I in comparison to the others (P = 0.001).ConclusionsA low dosage of iron treatment every other day may be used in the place of providing iron once or twice every day with similar effectiveness and lower rates of GIS side‐effects.
Performance of simple serum‐based tests to exclude cirrhosis prior to hepatitis C treatment in non‐hospital settings in Australia
Authors: Burrage Lauren , Zimmerman Henry , Higgins Sarah , Param Kerrin , Orme Clare , Mitchell Jonathan , O'Beirne James 
Published: January 2020

AbstractBackgroundCurrent guidelines suggest using transient elastography (TE) or aspartate aminotransferase to platelet ratio index (APRI) score <1 to exclude cirrhosis prior to commencing treatment for hepatitis C virus (HCV). Recently, fibrosis‐4 (FIB‐4) <0.93 has been shown to have a high negative predictive value (NPV) for the presence of cirrhosis.AimsTo assess FIB‐4 and APRI in a cohort of HCV patients and to validate FIB‐4 <0.93 in populations of HCV‐infected individuals with differing cirrhosis prevalence, including secondary care, primary care and prisons.MethodsFrom our treatment database, we identified patients with complete data (n = 793). We calculated FIB‐4 and APRI and correlated this with the presence of cirrhosis, determined by TE. We analysed the performance of FIB‐4 and APRI using area under the receiver operating curve analysis. We calculated sensitivity, specificity, positive predictive value, NPV and number of patients misclassified using published cut‐offs in populations with varying cirrhosis prevalence.ResultsFIB‐4 was superior to APRI for the diagnosis of cirrhosis (area under the receiver operating curve 0.868 vs 0.802). In secondary care (cirrhosis prevalence 32%), APRI <1 had a NPV of 80% and misclassified 14% of patients. FIB‐4 <0.93 had a NPV of 97% and misclassified 1%. In primary care and prison (cirrhosis prevalence 13% and 8%), the NPV for APRI <1 was 93% and 96%, respectively, but 5% of patients with cirrhosis were misclassified. FIB‐4 <0.93 had excellent NPV in both primary care (97%) and prisoners (100%).ConclusionsFIB‐4 <0.93 is highly efficient at ruling out cirrhosis in HCV patients and allows TE to be appropriately avoided, thereby streamlining treatment algorithms.
Persistent Underinvestment in Public Agricultural Research
Authors: Oehmke James F. 
Published: January 2020

AbstractIt is often argued that public support of agricultural research is inadequate. However, the empirical papers that support this hypothesis rarely reflect formal behavioral theory capable of explaining this phenomenon. This paper presents a theory that explains underfunding, namely, that funding agencies respond too slowly to secular changes in the value of research. A model of farmer and funding agency behavior is presented, and shown to imply that actual research funding will be consistently smaller than optimal funding. The assumptions and results of the model are explained in terms of the institutional literature on public agricultural research agencies.
An Evaluation of Indian Government Rice Policy in Tamil Nadu
Authors: Chellaraj G. , Brorsen B. Wade 
Published: January 2020

AbstractThe Indian government procures rice from wholesalers or producers at a price below the market price and then distributes it to low‐income consumers at a subsidized price. This paper uses a simulataneous equations econometric model to evaluate the effects of this policy on supply/demand of rice in the state of Tamil Nadu, between 1956 and 1985. Results show that production is more responsive to power for irrigation and fertilizer prices than to output prices. Because supply is inelastic, producers bear the burden of the ‘tax’ imposed by procurement even though rice is procured from the wholesaler. Rice distributed by the government displaces rice demanded in the open market, and thus the government distribution of rice has not increased the total consumption of rice.
Issues relating to Agricultural Pricing Policies and their Analysis in Developing Countries
Authors: Lutz Ernst , Saadat Yasmin 
Published: January 2020

AbstractAgricultural pricing policies in developing countries are often the result of complex interactions between producer, consumer and merchant groups and their relative effectiveness in influencing government decision making. Even within governments, various ministries often have opposing views. In this environment one of the contributions a policy analyst can make is to attempt to quantify the effects of different policy options. This permits a more informed discussion which hopefully leads to better decision‐making and an improved incentive environment.Many analyses of agricultural pricing policies have used the standard partial equilibrium analysis where no linkages between commodity markets were considered. In this paper we have considered cross‐price effects. Also, we have discussed issues relating to other adjustments/refinements of the standard method so that a practitioner not familiar with the various methods can form an opinion of what the options are and what adjustments may be appropriate for a particular case in question. The adjustments relate to overvaluation of currencies, input price distortions, differences in the degree of distortions between producers and consumers, and variability of border prices.The inclusion of cross‐price elasticities was important for assessing production, consumption and trade effects for Argentina, but for the other countries it resulted in only somewhat improved accuracy. The adjustment for exchange rates had a large impact in Egypt and was important for other countries as well. This underlines the importance of exchange rates as key variables for agricultural pricing policies in general. The numbers show that the traditional taxation policies of agricultural products in the sample of developing countries is somewhat less widespread than in the past. These policies, however, continue to favor consumers over producers, with significant losses for some of the latter. The large size of welfare losses, especially compared to efficiency losses, highlights the importance of correcting distorted prices that adversely affect the poorest sections of society. Also, the usual government objective of taxing producers to raise revenues is frequently defeated by the large subsidies provided to consumers.For the partitioner, for whom time is often of the essence, the assessment of welfare effects using the partial equilibrium method may provide reasonably good ‘first cut’ estimates of the order of magnitude of the impact of distortions. But often, these 'base case estimates' can and should be adjusted for a number of possible factors. The analyst needs to determine how important accurate estimates of key variables are to the policy makers; he or she then needs to compare the costs involved in generating or gathering the data and doing the calculations with the benefits of a broader and more accurate analysis of the distortionary effects of the particular case in question.
Principles of Dynamic Optimization in Resource Management
Authors: Kennedy John O.S. 
Published: January 2020

AbstractThe type of resource problem amenable to static analysis is distinguished from that requiring dynamic analysis. Possibly due to the apparent complexity of optimal control theory methods, often dynamic models have not been applied where they would be appropriate. In this article dynamic programming arguments are used to derive optimality conditions directly and simply. They are derived for a renewable resource such as a fishery, but they have application to resource management in general. The approach is illustrated by examples to the extraction of a depletable resource, to feeding for weight gain, and to applying fertilizer when some fertilizer carriers over from one crop season to another. Conditions for the optimal replacement of biological units are also considered.
A Linear Programming Algorithm for Determining Mean‐Gini Efficient Farm Plans
Authors: Okunev John , Dillon John L. 
Published: January 2020

AbstractA linear programming algorithm is presented for determination of farm plans that are efficient under the mean‐Gini criterion. Use of the algorithm is illustrated by applying it to a standard problem from the literature. The set of efficient plans is compared with those based on mean‐variance and MOTAD analysis of the same problem.
A Note on Private Farm Management Consulting Services: The Case of Argentina
Authors: Gallacher Marcos 
Published: January 2020

AbstractThe paper discusses the evolution and perspectives of private farm management consulting in Argentina. In the first part, recent developments in consulting services are presented. Because of its importance, particular emphasis is placed in the evolution of consulting work done in the framework of the CREA (Consorcios Regionales de Experimentación Agricola) association of farm producers. Rough estimates show that: (a) private consulting represents 10‐15% of total manpower devoted to direct farmer advice, and (b) demand for consulting work has grown considerably faster in areas where farms have mixed (crop‐livestock) production systems.The possible incentives for farmers hiring consulting services are summarized. The widespread (in Argentina) opinion that consultants allow higher yields from a given input mix is not fully supported by the empirical data presented in this paper: there is evidence that yield differences found on farms are caused not only by the presence or absence of consultants but also (and perhaps primarily) by differences in land quality. The fact that the average farmer may be (at least on a yield basis) as efficient as the ‘top’ farmers should be further studied, as it has important implications from a policy point of view.
Malawi's Agricultural Development: A Success Story?
Authors: Sofranko Andrew J. , Fliegel Frederick C. 
Published: January 2020

AbstractAt a time when attention was focused on Africa's poor agricultural performance, Malawi demonstrated a capacity not only to feed itself, but to produce a surplus for export. During the periods covered in this paper, its agricultural growth exceeded that of most African countries and compared favorably with 'success stories' on the continent. This research focuses on Malawi's recent performance, with particular attention on trends in the provision of essential agro‐support services: credit; extension and farmer training; and input supply and marketing. Trends in these services are examined first at the national level and then at the district level. While overall trends indicate substantial progress, district level data reveal extensive unevenness. Moreover, at the farm level, census data on farmer training and technology utilization show fewer benefits to female operators and smaller farmers.Important elements of developmentally oriented infrastructure and services have been put in place and are functioning better than in most African countries. This is important in terms of longer‐term agricultural development prospects. There is ample evidence, however, that Malawi's progress has not spread across different segments of the farm population or Agriculture Development Districts. Both the unevenness and overall progress have been heavily influenced by donor‐support.
Evaluating Agricultural Energy Policies Under Uncertainty: The Case of Electricity in South India
Authors: Babu Suresh Chandra , Hallam Arne 
Published: January 2020

AbstractFarmers' attitude towards risk associated with the availability of energy inputs will influence their investment behavior and demand for energy inputs. In order to analyze policies that reduce the risk in energy availability, some modifications in methods are required. This study, using a mean‐variance framework, demonstrates how cross‐sectional data and time‐series data on crop yields and prices can be used to analyze agricultural energy policies under uncertainty in a developing country context. It is argued that the farmers risk attitudes, their crop allocation behavior, changes in the demand for energy inputs and the stochastic relationship between various forms of energy inputs can be explained by the various energy constraints faced by them. Furthermore, using the same methods the impact of policies which affect these constraints, can be analyzed.
Derivation of Long‐run Factor Demands from Short‐run Responses
Authors: Guyomard Hervé , Vermersch Dominique 
Published: January 2020

AbstractThe concept of the restricted cost function provides a dual approach to the analysis of short‐run technology. It allows also, under curvature restrictions, inference of the different possible equilibria, according to constraints on the firms. Moreover, in this paper, the properties of the restricted cost function are spelled out. Substitution possibilities related to the different regimes are also derived from the restricted cost function.This theoretical framework is applied to characterize the French cereal‐producing sector by using a cross‐section of farms.
Does Agricultural Growth in Poor Countries Harm Agricultural‐Exporting Rich Countries?
Authors: Anderson Kym 
Published: January 2020

AbstractThe commonly held view that agricultural‐exporting developed countries would lose from agricultural growth in less‐developed countries (LDCs) is shown to be based on an incomplete argument. It considers only the effects on LDC agricultural supply, or at best only that and the first‐round effects of increased farmer incomes on the demand for tradables. What also needs to be considered is the effect on the demand for nontradables and hence the second‐round effects of increased spending by producers of nontradables. When all these effects are considered, the positive correlations obtained between agricultural output growth in LDCs and agricultural imports from developed countries is not surprising. It is then shown that selling or giving away agricultural research and management skills to developing countries can be beneficial to developed countries, including agricultural exporters: by setting out to do good, they may end up also doing well.
An econometric choice for extension‐teaching methods: the Ilorin and Oyo North Agricultural Development Projects' experience
Authors: Umeh J. Chinedu 
Published: January 2020

ABSTRACTThe appropriate combination of extension‐teaching methods for rapid farm‐technology diffusion and sustained productivity growth in the World‐Bank‐Assisted Agricultural Development Project in rural Nigeria is examined. The multiple extension‐teaching methods in the Ilorin and Oyo North Projects have led to self‐defeating and counterproductive results. Using principal‐components analysis, the ten extension‐teaching methods (variables) are transformed into a linear equation by allocating relative weights to each variable. These weights (coefficients of the equation), which are reasonably unique to each variable, measure the relative importance of the variables and therefore facilitate their ranking in each of the project districts.The usefulness of the principal component model in the World‐Bank‐Assisted Agricultural Development Projects in particular, and the rural Nigerian agricultural industry in general, are briefly discussed.
Developing country debt: implications for agricultural trade
Authors: Gunasekera H. Don B.H. , Bowen Bruce , Andrews Neil 
Published: January 2020

ABSTRACTThere has been a sharp decline in the rate of economic growth in many developing countries in the 1980s compared with the 1970s. Reduced availability of external finance following the international debt crisis has been identified as one of the most important factors responsible for this decline. At the same time there has been a slowdown in the rate of growth of food imports to these countries, particularly to the highly indepted ones.The focus in the paper is on the implications for international agricultural commodity markets of a dept write‐off in developing countries. To analyse these implications a world agricultural trade model is used. Specifically, the analysis covers the effect of existing debt on the permanent incomes of developing debtor countries and developed creditor countries, and hence the effect on agricultural commodity markets.The results indicate that, if the debts of the developing countries were written off, prices would improve in consequence of the resulting rise in their permanent incomes. If the debt write‐off also led to growth in developing countries returning to the levels prevalent before the debt crisis, the improvements in world prices would be likely to be much larger.
Variability in wheat export demand elasticity: Policy implications
Authors: Devadoss S. , Meyers William H. 
Published: January 2020

ABSTRACTAgricultural economists and policy makers in the United States believe that the magnitude of the export demand elasticity is one of the most important parameters used in farm policy decisions. However, past empirical estimates show wide variation in the size of the U.S. export demand elasticity. Reasons for this wide variation go beyond differences in model specification, estimation methods, and period of estimation to involve factors such as trade policies and changes in the supply and demand conditions of foreign countries. In view of the continual variation in magnitude, the elasticity of export demand should be viewed as a variable rather than as a parameter. In this study, U.S. wheat export demand elasticities are computed using a world wheat trade model. The estimates show that the elasticities vary significantly over time. They also reveal that elimination of trade barriers would more than double wheat export demand elasticities.