In this paper we introduce a notion of spectral approximation for directed graphs. While there are many potential ways one might define approximation for directed graphs, most of them are too strong to allow sparse approximations in general. In contrast, we prove that f...

Abstract Production of clean, low-carbon energy and by-products is possible through the use of highly integrated, efficient systems such as polygeneration plants. Mathematical programming methods have proven to be valuable for the optimal synthesis of such systems. Howe...

Palliative care is a basic human right and end-of-life is a public health issue. According to the 2006 mapping exercise of the International Observatory on End-of-Life Care, the Philippines is categorized as under Group 3 together with other countries with localized pal...

Upland rice (Oryza sativa L.) yields on infertile, acid soils in the Asian uplands average only 1 Mg ha-1. Phosphorus deficiency is considered a major soil constraint to increased yield, but little quantitative information is available. We analyzed P responses of tradit...

A study was undertaken to investigate the variability among lowland rice cultivars and the mode of gene action of aluminum (Al) toxicity tolerance in rice. Pregerminated seeds were grown in a nutrient solution containing 30 ppm Al and in normal nutrient solution, and re...

Publisher Summary A realistic approach to crop protection should consider the various pests, including diseases that affect a crop. Epidemiologists are frequently confronted with large data sets representing information on the characterization, the dynamics, or the beha...

ABSTRACT Objective Hypertension is the most important modifiable risk factor for stroke globally. We hypothesised that country-income level variations in knowledge, detection and treatment of hypertension may contribute to variations in the association of blood pressure...

Abstract Background Traumatic brachial plexus injuries are devastating injuries with lifelong disability and pain. The objective of this paper was to determine the functional disability of adult patients with traumatic brachial plexus injuries. Patients and methods A cr...

El presente estudio repasa las principales aportaciones en el campo de la historia del libro en Filipinas, haciendo énfasis en los aportes de los primeros bibliógrafos y comentando los impresos xilográficos descubiertos en la segunda mitad del siglo XX. A la luz de las ...