Migration routes

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Orientation and autumn migration routes of juvenile sharp tailed sandpipers at a staging site in Alaska

Orientation and autumn migration routes of juvenile sharp tailed sandpipers at a staging site in Alaska

Arctic waders are well known for their impressive long-distance migrations between their high northerly breeding grounds and wintering areas in the Southern hemisphere. Performing such long migrations requires precise orientation mechanisms. We conducted orientation cage experiments with juvenile sharp-tailed sandpipers ( Calidris acuminata ) to investigate what cues they rely on when departing from Alaska on their long autumn migration flights across the Pacific Ocean to Australasia, and which possible migration routes they could use. Experiments were performed under natural clear skies, total overcast conditions and in manipulated magnetic fields at a staging site in Alaska. Under clear skies the juvenile sharp-tailed sandpipers oriented towards SSE, which coincides well with reported sun compass directions from their breeding grounds in Siberia towards Alaska and could reflect their true migratory direction towards Australasia assuming that they change direction towards SW somewhere along the route. Under overcast skies the sandpipers showed a mean direction towards SW which would lead them to Australasia, if they followed a sun compass route. However, because of unfavourable weather conditions (headwinds) associated with overcast conditions, these south-westerly directions could also reflect local movements. The juvenile sharp-tailed sandpipers responded clearly to the manipulated magnetic field under overcast skies, suggesting the use of a magnetic compass for selecting their courses.

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Migration routes and strategies of Grey Plovers (Pluvialis squatarola) on the East Atlantic Flyway as revealed by satellite tracking

Migration routes and strategies of Grey Plovers (Pluvialis squatarola) on the East Atlantic Flyway as revealed by satellite tracking

Therefore, we conducted a pilot study on the spatial and temporal patterns of Grey Plover migration using satel- lite transmitters. For the first time we determined spring and autumn migration routes of individual Grey Plovers on the EAF, the locations of their breeding, staging and wintering grounds, as well as the timing, speed and dura- tion of the entire migration. Analysing different speed and duration variables for differences between the migration seasons is important to understand ecological constraints (e.g. Schmaljohann 2018). If birds follow a time-minimiz- ing strategy sensu Alerstam (Alerstam and Lindström 1990; Alerstam 2011) we expect faster migration in spring as compared to autumn because spring migrants may be forced to arrive at breeding grounds as early as possible to benefit from higher reproduction opportunity (Kokko 1999). As overall migration speed is basically due to the number of stopovers and their durations rather than flight speed, we expect that spring migrants undertake less and/ or shorter stopovers than autumn migrants. Furthermore, we expect that spring migrants do not follow the short- est migration route (great circle route; Alerstam 2001) between the Wadden Sea and their northern Siberian breeding grounds rather follow a more southerly, longer but inland migration route with more predictable stopo- ver sites and better habitat availability as some other wader species do (Green et al. 2002; Green 2004).

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High attack rate for malaria through irregular migration routes to a country on verge of elimination

High attack rate for malaria through irregular migration routes to a country on verge of elimination

Of the total number of returnees screened (n=534), 32 were positive for P. falciparum . Nearly two thirds (n=19) were identified at the point of entry at the BIA and 13 during district level follow-up. The total number of mal- aria cases from irregular migration routes in accounted for 76% (32/42) of the total number of P. falciparum cases detected in Sri Lanka in 2012. This route contrib- uted to 46% (32/70) of the total number of imported malaria cases in the same year. Imported cases overtook indigenously acquired cases of malaria for the first time in Sri Lankan in 2012, contributing to three-quarters of the total malaria burden (70/93).

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Migration routes and habitat use of a highly adaptable salmonid (sea trout, Salmo trutta) in a complex marine area

Migration routes and habitat use of a highly adaptable salmonid (sea trout, Salmo trutta) in a complex marine area

Migration patterns revealed an initial movement into shallow or highly stratified marine areas (Kattegat or the Wadden Sea) during the first weeks at sea followed by a migration into deeper and more well-mixed areas (The North Sea and Skagerrak) during the end of May and beginning of June. The Kattegat and Wadden Sea heat up more quickly than the North Sea and Skagerrak, and the reconstructed tracks, therefore, provide a geographic layer of explanation to the direct measurements reported in [27] where the kelts resided in waters warmer than the mean for the region when mean temperatures were below 15 °C and colder than the mean when mean tem- peratures were above 15 °C. Although the migrations are on a different scale, this horizontal migration has similar- ity with that observed for sea trout within a Norwegian fjord system [9]. In addition, the kelts in the present study migrated into areas with lower salinities during their first 15 days at sea (P < 0.0001). The migration of the fish may, thus, optimize their aerobic scope and support growth [21–23].

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Orientation of native versus translocated juvenile lesser spotted eagles (Clanga pomarina) on the first autumn migration

Orientation of native versus translocated juvenile lesser spotted eagles (Clanga pomarina) on the first autumn migration

The ontogeny of migration routines used by wild birds remains unresolved. Here we investigated the migratory orientation of juvenile lesser spotted eagles (LSE; Clanga pomarina) based on translocation and satellite tracking. Between 2004 and 2016, 85 second-hatched juveniles (Abels) were reared in captivity for release into the declining German population, including 50 birds that were translocated 940 km from Latvia. In 2009, we tracked 12 translocated juveniles, as well as eight native juveniles and nine native adults, to determine how inexperienced birds come to use strategic migration routes. Native juveniles departed around the same time as the adults and six of eight used the eastern flyway around the Mediterranean, which was used by all adults. In contrast, translocated juveniles departed on average 6 days before native LSEs, and five travelled southward and died in the central Mediterranean region. Consequently, fewer translocated juveniles (4/12) than native juveniles (7/8) reached Africa. We conclude that juvenile LSEs have a much better chance of learning the strategic southeastern flyway if they leave at an appropriate time to connect with experienced elders upon departure. It is not clear why translocated juveniles departed so early. Regardless, by the end of the year, most juveniles had perished, whether they were translocated (10/12) or not (6/8). The small number of surviving translocated juveniles thus still represents a significant increase in the annual productivity of the German LSE population in 2009.

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The geographical scale factor in orientation of migrating birds

The geographical scale factor in orientation of migrating birds

Detailed knowledge about the flight routes may be used to test predictions about optimal orientation according to theoretical principles and about the use of compasses based on celestial or magnetic cues. Ringing recoveries demonstrate that the migratory journey of many species, such as the wheatear and willow warbler, is divided into successive legs with different main orientation. Autumn and spring migration routes are often different, sometimes diverging on a continental scale. Aerial radiotracking of whooping cranes in North America and satellite tracking of brent geese migrating from Iceland across the Greenland ice cap point to the significant role of large-scale topography for the shaping of migration routes. Compass and position control are also required, e.g. during long passages across featureless sea or ice, but how these elements are integrated into the birds’ orientation system

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No apparent gain from continuing migration for more than 3000 kilometres: willow warblers breeding in Denmark winter across the entire northern Savannah as revealed by geolocators

No apparent gain from continuing migration for more than 3000 kilometres: willow warblers breeding in Denmark winter across the entire northern Savannah as revealed by geolocators

Despite importance for understanding links to the sea- sonal environments as well as conservation [34], infor- mation about connectivity, migration routes and within- winter itinerancy [22] is generally scarce or lacking. Fur- thermore, few studies have evaluated the causes of con- nectivity at the behavioural level, for example migration direction or termination of migration [35]. Among- individual spread is often assumed to result from vari- ation in migration directions [36] but several other fac- tors could also be involved. Here, we use geolocators to describe migration routes, stopovers and wintering sites of male willow warblers P. t. trochilus breeding in Denmark. Despite the low spatial resolution, estimation of timing of movements and mapping of stopping-over locations at a regional scale is possible [37, 38]. We focus on the resulting migratory connectivity and the be- haviours causing it at the individual level. Overall, we find surprisingly little connectivity (large longitudinal spread compared to the wintering distribution of the studied subspecies) and test a range of possible causes, such as filling up of suitable habitat, dominance

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Measuring risk of attack on bus networks

Measuring risk of attack on bus networks

Instead, it may be easier to concentrate on the static factors which are not subject to change. If there was an unstable environment in the country it may be more effective to concentrate on the possible targets which is the biggest contributing factor in a number of cases. It could be possible to reroute a number of routes such as the 45 route which passes by six embassies. However, a balance needs to be found so that people do not panic and cease using public transport. In London, a high profile campaign warning people to be on the look out for anything suspicious proved to be very effective. However in Madrid, following the bombings, they decided against such a campaign as they did not want to discourage the use of public transport.

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Geographic Information System (GIS) modeling approach to determine the fastest delivery routes

Geographic Information System (GIS) modeling approach to determine the fastest delivery routes

In this research it was demonstrated how GIS is applied in order to obtain the best calculation results to derive the fastest delivery service routes. This paper presented the implementa- tion of statistical analysis using a regression model to identify the key factors affecting driving time. The regression model can provide information needed to estimate the values of a dependent variable when the independent variables’ values are known and there is a relationship between the two vari- ables. The regression model used in this study was explained, followed by the identification of variables as key factors in modeling that aid with the decision-making process for trans- portation planning.

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Sign count approximation using field inventory sampling and calculated sign densities: Analysis, improvements, and methods

Sign count approximation using field inventory sampling and calculated sign densities: Analysis, improvements, and methods

It is recommended that one additional extension study be done. Not for the purpose of the NCDOT, but for the purposes of North Carolina as a whole. It is important to determine the number of signs located within the cities of North Carolina. Due to the low number of “stop” signs on urban secondary roads, with virtually zero on primary routes, it would be good to know how much burden will be placed on the cities and towns by the new retroreflectivity criteria. The absence of stop signs on primary routes begs the question of where all the stop signs really are. Clearly, with about 51,000 on secondary roads we have identified where the state maintained stop signs are located. However, the authors believe that there are many more on city roads and streets. Reflectivity standards, therefore, will significantly impact these municipalities and are of potential concern.

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Study of Model for Selection of Priorities for Development of Cargo Transportation

Study of Model for Selection of Priorities for Development of Cargo Transportation

The organisation and formation of the route from the groups of cars of different owners may be provided according to the station technological processes by a transporter, operator - rolling stock owner, structural subdivisions of railways and access roads of senders or on station tracks, which are leased by the branch railway lines owners and their counterparties. The following routes of i-categories are taken in account in the routing: 1 — the main rail network direct routes of the operator; 2 — stepping routes under contracts for the operation of access to rail or for serving and cleaning cars taking into account the responsibility of the cargo sender; 3 — routes to the station for spraying or to spraying points for forwarding cars picked up at unloading stations, districts, cargo points and consignees within the limits established by the operator of the main railway network; 4 — routes to incoming or distribution stations receiving fuel cargoes agreed by the main rail network operator [2-4, 7] The model of organization of the route from the groups of cars of different owners in the conditions of operation of the transport and logistics centre is a two-stage stochastic task with recursion and random right-hand side restrictions. The variables of the first stage are denoted n j , and the recursive variables, respectively, s i l and x ik l . If the current state of the network { a ik , y 0 } is given then the task is to minimize the costs of forming and following the departure route q i  , the expected network maintenance costs and the conditions for non-compliance fees, and other car flows on the voyage route.

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ACCESSIBLE TOURISM FOR ALL – CURRENT STATE IN THE CZECH BUSINESS AND NON-BUSINESS ENVIRONMENT

ACCESSIBLE TOURISM FOR ALL – CURRENT STATE IN THE CZECH BUSINESS AND NON-BUSINESS ENVIRONMENT

Disabled people´s interest in travel, getting to know new things, recreation or culture is on the rise, regardless of their type of disability. Integration of people with disabilities into regular life is being resolved at a constantly growing rate. In many cities or holiday destinations, the public transport, public service buildings (post offi ces, banks, hospitals), stores, etc., are becoming completely or partly barrier free. Projects aimed at creating barrier-free access have been carried out, e.g., in Bordeaux, Barcelona, and in the Czech Republic, e.g., Olomouc. Areas with attractive primary offer for tourism are joining these initiatives. Among examples of good experience are, e.g., Valencia with its accessible beaches, Girona with the making of accessible tourist routes, Vienna with its special information portal for the hearing impaired, United Kingdom and Paris with their

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Comparison of alternative linear referencing system route generation approaches

Comparison of alternative linear referencing system route generation approaches

Directionality isn't the most important topic, but in order to obtain feasible results, directionality must be given focused consideration. To assign LRS IDs for this project, directions of south to north and west to east were used. Although some roads did not completely run in these directions, the goal was to create longer individual LRS's while eliminate circling and wandering of the LRS routes. However, the secondary LRS routes provided unusual situations that couldn't be avoided. Curving and looping of roads (in which the entire loop was assigned the same link number) occurred because no other intersections created the need for an extra node, did exist and some roads ended up being quite curved.

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A Virtual Grid Based Dynamic Routes Adjustment (VGDRA) Scheme for   Wireless Sensor Networks Based on Sink Mobility

A Virtual Grid Based Dynamic Routes Adjustment (VGDRA) Scheme for   Wireless Sensor Networks Based on Sink Mobility

The Authors in [6] have says recently, a VGDRA scheme for mobile sink-based wireless sensor networks is introduced. This paper presents the proposed implementation of VGDRA, in which we are discussing the approach of efficient data delivery using communication of distance priority i.e. avoiding straight line communication which was used in previous VGDRA scheme. In this paper, we present a VGDRA scheme that aims to minimize the routes reconstruction cost of the sensor nodes while maintaining nearly optimal routes to the latest location of the mobile sink. We propose a set of

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Routes to Knowledge

Routes to Knowledge

Knowledge”- which seeks to re-position libraries in the Knowledge Society and develop capacity so their potential can be realised. Routes to Knowledge will engage with the library and information world to produce an Action Plan by March 2005. Actions will fall under headings such as user need, strategic framework, advocacy, network development, access, funding, workforce, information literacy and knowledge management. The relevance of these activities to research (and vice-versa) is discussed.

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A Survey of Mobile Ad Hoc Network Attacks

A Survey of Mobile Ad Hoc Network Attacks

5) Rushing Attack: On-demand routing protocols that use duplicate suppression during the route discovery process are vulnerable to this attack. An adversary node which receives a Route Request packet from the source node floods the packet quickly throughout the network before other nodes which also receive the same Route Request packet can react. Nodes that receive the legitimate Route Request packets assume those packets to be duplicates of the packet already received through the adversary node and hence discard those packets. Any route discovered by the source node would contain the adversary node as one of the intermediate nodes. Hence, the source node would not be able to find secure routes, that is, routes that do not include the adversary node. It is extremely difficult to detect such attacks in ad hoc wireless networks.

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Evaluation of routes to headship: appendices

Evaluation of routes to headship: appendices

We undertook a survey with current and past participants from the programmes the link for which was distributed by the programme providers. We wanted also to gather views from those who have not participated in a routes to headship programme but who are at a senior level, either Depute Headteacher or Principal Teacher. Rather than undertake this across all authorities we agreed to send this out through seven local authorities covering a range of sizes and geographical areas. We received 320 responses to the participants‟ survey.

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Refugees and progression routes to employment

Refugees and progression routes to employment

Migrants, on the other hand, generally leave their home countries for economic reasons i.e., to better themselves. They may have pre-planned arrangements to satisfy immigration requirements. They leave with expectations that they will have to find their own routes to economic prosperity. In time, as they settle their families often follow. This can also occur with refugees. The first generation of Afro-Caribbean and Asian migrants who migrated to the U.K. in the 50s and 60s after the Second World War are a good example of peoples invited to fill a labour shortage. Yet today, immigrants provide even greater benefits to Western economies. In 1999, 16 million legal immigrants in Europe earned more than $400 billion. The number of self-employed immigrants in the E.U. has increased by close to 20 per cent over the past seven years. In Italy, immigrants make up one third of labour in industrial and service sectors, even though they only comprise 2 per cent of the total population. In the U.K., the Chinese have a higher proportion of people working in the professions than non- Chinese and Indians earn more than the average family income of the rest of the population (Time magazine, July 2000). What this shows is that if given appropriate support, refugees can make a significant contribution to the economic life of the U.K.

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Natural and artificial routes to pluripotency

Natural and artificial routes to pluripotency

ABSTRACT Pluripotent cells of the blastocyst inner cell mass (ICM) and their in vitro derivatives, embryonic stem (ES) cells, contain genomes in an epigenetic state that are poised for subsequent differentiation. Their chromatin is hyperdynamic in nature and relatively uncondensed. In addi- tion, a large number of genes are expressed at low levels in both ICM and ES cells. Also, the chromatin of naturally pluripotent cells contains specialized histone modification patterns such as bivalent domains, which mark genes destined for later developmentally-regulated expression states. Female pluripotent cells contain X chromosomes that have yet to undergo the process of X chromosome inactivation. Collectively, these features of very early embyronic chromatin are required for the successful specification and production of differentiated cell lineages. Artificial reprogramming methods such as somatic nuclear transfer (SCNT), ES cell fusion-mediated reprogramming (FMR), and induced pluripotency (iPS) yield pluripotent cells that recapitulate many features of naturally pluripotent cells, including many of their epigenetic features. However, the route to pluripotent epigenomic states in artificial pluripotent cells differs drastically from that of their natural counterparts. Here, we compare and contrast the differing routes to pluripotency under natural and artificial conditions. In addition, we discuss the intrinsically metastable nature of the pluripotent epigenome and consider epigenetic aspects of reprogramming that may lead to incomplete or inaccurate reprogrammed states. Artificial methods of reprogramming hold immense promise for the development of autologous cell graft sources and for the development of cell culture models for human genetic disorders. However, the utility of artificially repro- grammed cells is highly dependent on the fidelity of the reprogramming process and it is therefore critically important to assess the epigenetic similarities between embryonic and induced pluripo- tent stem cells.

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Migration and mission routes/roots in Oceania

Migration and mission routes/roots in Oceania

I imagine that there can be several explanations for why our ancestors left their first homes: natural cause, supernatural inkling, spirit of explora- tion, fleeing personal or social matters, or because they were pushed away. I suspect that they did not set to sea in order to spread some godforsaken tradition or culture. I do not believe that they knew where they were going, just as we don’t know from where they came. I want to believe that they voy- aged because there is something intoxicating about drifting away from safety to live floating lives—like what locals in Onotoa call Aba tabebeiti , float- ing lands—and set roots along one’s routes. In other words, they migrated because they preferred to live and think in transit. They were not disciples of Elijah, who wanted Israel to stop wavering between two opinions and instead decide whether to be on the side either of Ba’al or of Yhwh (1 Kings 18:16–29). 11 As a sea people, our ancestors were transiting people, between

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