Past global climate changes had strong regional expression. To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia. The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the nineteenth century. At multi-decadal to centennial scales, temperature variability shows distinctly different regional patterns, with more similarity within each hemisphere than between them. There were no globally synchronous multi-decadal warm or cold intervals that define a worldwide Medieval Warm Period or Little Ice Age, but all reconstructions show generally cold conditions between AD 1580 and 1880, punctuated in some regions by warm decades during the eighteenth century. The transition to these colder conditions occurred earlier in the Arctic, Europe and Asia than in North America or the Southern Hemisphere regions. Recent warming reversed the long-term cooling; during the period AD 1971-2000, the area-weighted average reconstructed temperature was higher than any other time in nearly 1,400 years

Every effort should be made to reinstate bedside teaching as a leading component of medical training.

Results highlight the positive perception and attitude of medical teachers toward the integration of SBME in undergraduate curriculum. Prior formal training of teachers created a different perception. Top perceived barriers for effective SBME include teachers' formal training supported with time and resources and the early integration into the curriculum. These critical challenges need to be addressed by medical schools in order to enhance the integration SBME in undergraduate curricula.

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Purpose This paper aims to present the studies which were carried out to determine building typology in Northern Pakistan, which is a seismically active region. Design/methodology/approach A total of 41 towns and cities were surveyed to collect the data of building types. Help was also taken from global positioning system and satellite imagery. Findings In total, 14 different types of buildings were identified in the region based on the structural system and combination of wall and roof materials; each of them was assigned an appropriate designation. The walls in these buildings were made of block, stone or brick, whereas the roof consisted of corrugated galvanised iron sheet, thatched roof, precast concrete planks or reinforced concrete (RC). Only 6 per cent buildings were found to be engineered RC buildings; this indicates a significance proportion of non-engineered building stock in Northern Pakistan. Research limitations/implications The surveys were conducted in some of the selected areas. Other areas are beyond the scope of this work. Practical implications The presence of a huge deficient building stock in Pakistan indicates a major seismic risk. The seismic losses are largely dependent on the earthquake resistance of existing buildings and building stock. An inventory of existing buildings and their types can help in assessing seismic vulnerability of the built environment, which may lead to the development of policies for seismic risk reduction. Originality/value Presently, housing encyclopaedia does not exist in Pakistan. As a result, housing typology in the country is not known. The presented study addresses this gap in part. Housing typology surveys were conducted to study the typical construction practices in the selected areas and to determine the proportions of different building types in the overall building stock.

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Abstract-With the increasing number of vehicles in use in our daily life and the rise of traffic congestion problems, many methods and models have been developed for real time optimisation of traffic lights. Nevertheless, most methods which consider real time physical queue sizes of vehicles waiting for green lights overestimate the optimal cycle length for such real traffic control. This paper deals with the development of a generic hybrid model describing both physical traffic flows and control of signalised intersections. The firing times assigned to the transitions of the control part are considered dynamic and are calculated by a simplified optimisation method. This method is based on splitting green times proportionally to the predicted queue sizes through input links for each new cycle time. The proposed model can be easily translated into a control code for implementation in a real time control system.

Secure routing is vital to the acceptance and use of Wireless Sensor Networks (WSN) for many applications. However, providing secure routing in WSNs is a challenging task due to the inherently constrained capabilities of sensor nodes. Although a wide variety of routing protocols have been proposed for WSNs, most do not take security into account as a main goal. Routing attacks can have devastating effects on WSNs and present a major challenge when designing robust security mechanisms for WSNs. In this paper, we examine some of the most common routing attacks in WSNs. In particular, we focus on the wormhole routing attack in some detail. A variety of countermeasures have been proposed in the literature for such attacks. However, most of these countermeasures suffer from flaws that essentially render them ineffective for use in large scale WSN deployments. Due to the inherent constraints found in WSNs, there is a need for lightweight and robust security mechanisms. The examination of the wormhole routing attack and some of the proposed countermeasures makes it evident that it is extremely difficult to retrofit existing protocols with defenses against routing attacks. It is suggested that one of the ways to approach this rich field of research problems in WSNs could be to carefully design new routing protocols in which attacks such as wormholes can be rendered meaningless.