Satellite remote sensing reveals a positive impact of living oyster reefs on microalgal biofilm development

Satellite remote sensing (RS) is routinely used for the large-scale monitoring of microphytobenthos (MPB) biomass in intertidal mudflats and has greatly improved our knowledge of MPB spatio-temporal variability and its potential drivers. Processes operating on smaller scales however, such as the impact of benthic macrofauna on MPB development, to date remain underinvestigated. In this study, we analysed the influence of wild Crassostrea gigas oyster reefs on MPB biofilm development using multispectral RS. A 30-year time series (1985-2015) combining high-resolution (30 m) Landsat and SPOT data was built in order to explore the relationship between C. gigas reefs and MPB spatial distribution and seasonal dynamics, using the normalized difference vegetation index (NDVI). Emphasis was placed on the analysis of a before-after control-impact (BACI) experiment designed to assess the effect of oyster killing on the surrounding MPB biofilms. Our RS data reveal that the presence of oyster reefs positively affects MPB biofilm development. Analysis of the historical time series first showed the presence of persistent, highly concentrated MPB patches around oyster reefs. This observation was supported by the BACI experiment which showed that killing the oysters (while leaving the physical reef structure, i.e. oyster shells, intact) negatively affected both MPB biofilm biomass and spatial stability around the reef. As such, our results are consistent with the hypothesis of nutrient input as an explanation for the MPB growth-promoting effect of oysters, whereby organic and inorganic matter released through oyster excretion and biodeposition stimulates MPB biomass accumulation. MPB also showed marked seasonal variations in biomass and patch shape, size and degree of aggregation around the oyster reefs. Seasonal variations in biomass, with higher NDVI during spring and autumn, were consistent with those observed on broader scales in other European mudflats. Our study provides the first multi-sensor RS satellite evidence of the promoting and structuring effect of oyster reefs on MPB biofilms

SCHOOL LEADERSHIP IN THE 21ST CENTURY: SHARED EXPERIENCES OF THE CLARETIAN PRINCIPALS IN NORTHEAST INDIA

Education in the 21st century is rapidly progressing into new frontiers. Leadership of the education sector requires 21st century skills and mind-sets. Building and preparing principals to embrace and implement these new leadership skills is a critical challenge confronting the education sector today. The experiences of challenges, success and constraints faced by the principals in exercising their 21st century leadership skills need to be unearthed and made sense in order to navigate it with real expertise that twenty first century looks for. The purpose of this qualitative study was to explore the experience of principals’ readiness and preparedness for 21st century leadership skills and to describe and interpret them. The study used purposive sampling, semi-structured in-depth interviews for collecting the data, and Interpretative Phenomenological Analysis (Smith et al., 2009) for analyzing the data. The seven principals of Claretian-run secondary schools in northeast India were the participants of the study.The study brought out nine superordinate themes of experience in four domains of 21st century principal leadership and interpretive findings. A further analysis on four domains and their interpretive findings brought out four key leadership roles demonstrated by the principals, namely; 1) Supervising & managing the teaching and learning of the school 2) Stakeholder engagement 3) Personnel resource management and climate building 4) Innovative practice building & Technology resource management. Two dimensions namely, reflective and Claretian, emerged as factors influencing and guiding the leadership practices. The Four domain leadership findings and the framework of key leadership roles and competency models that emerged are in alignment with the six school leadership theories in the extant literature.Principals showed their readiness in four domains of 21st century leadership skills by demonstrating four key leadership roles and corresponding competency areas and skills. The key leadership roles are dynamically interrelated and permeated across the domains of 21st century principal leadership, while their importance in each domain has been significantly experienced by the principals

Sistema de avaliação de impactos de inovações tecnológicas: INOVA-tec system v. 2.0.

Este trabalho apresenta uma metodologia para a avaliação dos impactos de inovações tecnológicas, fornecendo informações organizadas de acordo com critérios e indicadores nas diversas dimensões onde os impactos da tecnologia sob avaliação podem ser percebidos. O método consiste de um sistema que permite a análise: i) do cenário no qual a tecnologia será introduzida, a partir da geração do índice de significância, e ii) do desempenho da inovação, pela análise dos indicadores de impacto que irão compor o índice de magnitude. Este sistema conta com uma ferramenta de apoio, o software "INOVA-tec v 2.0", com informações apresentadas como um norteador para permitir uma avaliação instruída e embasada.bitstream/item/42711/1/documentos-86.pd

A Free Trade Agreement between the United States and Mexico: The Right Choice

In this Article, Messrs. Silva and Dunn demonstrate that the intended Free Trade Agreement (FTA) between the United States and Mexico is a natural and necessary step in the two countries\u27 economic relations. Their approach is to trace the steps which have led to the FTA and to analyze the evolution and progression of Mexican economic, legal, and political polices which have reached a point permitting and necessitating a trade pact. An agreement between the two countries is both logical and compelled though it will have permanent consequences and potential obstacles. Nevertheless, the agreement must be implemented and with an ample degree of haste