Nitroglycerin-induced migraine type headache: bilaterally visible temporal arteries

A 37-year-old man presented to the emergency department suffering from headache, nausea and vomiting, which had started 1 h previously. He had been diagnosed with coronary artery disease and had been taking isosorbid-5-mononitrate, aspirin and metoprolol for 3 days. His vital signs and physical and detailed neurological examinations were normal except for a new onset of bilaterally visible, palpable and pulsatile temporal arteries. We discuss how nitrates can increase the cerebral and also temporal blood flow, which can rarely be seen with the naked eye, as was observed in this patient

Optimised solutions to the last-mile delivery problem in London using a combination of walking and driving

Inspired by actual parcel delivery operations in London, this paper describes a two-echelon distribution system that combines the use of driving and walking as part of last-mile deliveries in urban areas for a single driver. The paper presents an optimisation model that explicitly treats and integrates the driving and walking elements, and describes a branch-and-cut algorithm that uses new valid inequalities specifically tailored for the problem at hand. Computational results based on real instances obtained from a courier operating in London are presented to show the performance of the algorithm

Collaborative Parcels Logistics via the Carrier’s Carrier Operating Model

Parcel logistics in urban areas are characterized by many carriers undertaking similar activity patterns at the same times of day. Using substantial carrier manifest datasets, this paper demonstrates advantages from rival carriers collaborating using a “carrier’s carrier” operating model for their last-mile parcel logistics operations. Under these circumstances, a single carrier undertakes all the deliveries within a defined area on behalf of the carriers instead of them working independently. Modelling the daily delivery activity of five parcel carriers working over a 3.7 km2 area of central London, comprising around 3000 items being delivered to around 900 delivery locations, and consolidating their activity through a single carrier suggested that time, distance and associated vehicle emissions savings of around 60% could be achieved over the current business-as-usual operation. This equated to a reduction in the number of delivery vans and drivers needed from 33 to 13, with annual savings of 39,425 h, 176,324 km driven, 52,721 kg CO2 and 56.4 kg NOx. Reliance on vans and associated vehicle emissions could be reduced further by using cargo cycles alongside vans for the last-mile delivery, with estimated annual emissions savings increasing to 72,572 kg CO2 and 77.7 kg NOx. The results indicated that consolidation of items for delivery in this way would be especially beneficial to business-to-consumer (B2C) carriers whose parcel profiles comprise relatively small and light items. One of the key barriers to the wider take up of such services by individual carriers is the loss of individual brand identity that can result from operating through a carrier’s carrier

ICT for Sustainable Last-Mile Logistics: Data, People and Parcels

In this paper we present a vision of how ICT can be leveraged to help combat the impact on pollution, congestion and carbon emissions contributed by the parcel delivery sector. This is timely given annual growth in parcel deliveries, especially same-day deliveries, and the need to inform initiatives to clean up our cities such as the sales ban on new petrol and diesel vehicles in the UK by 2040. Our insights are informed by research on parcel logistics in Central London, leveraging a data set of parcel manifests spanning 6 months. To understand the impact of growing e-commerce trends on parcel deliveries we provide a mixed methods case study leveraging data-driven analysis and qualitative fieldwork to demonstrate how ICT can uncover the impact of parcel deliveries on delivery drivers and their delivery rounds during seasonal deliveries (or “the silly season”). We finish by discussing key opportunities for intervention and further research in ICT4S and co-created Smart Cities, connecting our findings with existing research and data as a call to the ICT4S community to help tackle the growth in carbon emissions, pollution and congestion linked to parcel deliveries

Optimising Parcel Deliveries in London Using Dual-Mode Routing

Last-mile delivery operations are complex, and the conventional way of using a single mode of delivery (e.g. driving) is not necessarily an efficient strategy. This paper describes a two-level parcel distribution model that combines walking and driving for a single driver. The model aims to minimise the total travelling time by scheduling a vehicle's routing and the driver's walking sequence when making deliveries, taking decisions on parking locations into consideration. The model is a variant of the Clustered Travelling Salesman Problem with Time Windows, in which the sequence of visits within each cluster is required to form a closed tour. When applied to a case study of an actual vehicle round from a parcel carrier operating in London, savings of over 20% in the total operation time were returned over the current situation where 104 transactions from 99 consignees were being delivered to 57 stopping points

Understanding the Impact of E-commerce on Last-Mile Light Goods Vehicle Activity in Urban Areas: The Case of London

Growth in e-commerce has led to increasing use of light goods vehicles for parcel deliveries in urban areas. This paper provides an insight into the reasons behind this growth and the resulting effort required to meet the exacting delivery services offered by e-retailers which often lead to poor vehicle utilisation in the last-mile operation, as well as the duplication of delivery services in urban centres as competitors vie for business. A case study investigating current parcel delivery operations in central London identified the scale of the challenge facing the last-mile parcel delivery driver, highlighting the importance of walking which can account for 62% of the total vehicle round time and 40% of the total round distance in the operations studied. The characteristics of these operations are in direct conflict with the urban infrastructure which is being increasingly redesigned in favour of walking, cycling and public transport, reducing the kerbside accessibility for last-mile operations. The paper highlights other pressures on last-mile operators associated with managing seasonal peaks in demand; reduced lead times between customers placing orders and deliveries being made; meeting delivery time windows; first-time delivery failure rates and the need to manage high levels of product returns. It concludes by describing a range of initiatives that retailers and parcel carriers, sometimes in conjunction with city authorities, can implement to reduce the costs associated with last-mile delivery, without negatively impacting on customer service levels

İki küçük avcının korkunç sergüzeştleri

M. K.'nın Yeni Yol'da tefrika edilen İki Küçük Avcının Korkunç Sergüzeştleri adlı romanıArşivdeki eksikler nedeniyle romanın tam metni verilememiştir. Bkz. Tefrika bilgi form

The scope for pavement porters: addressing the challenges of last-mile parcel delivery in London

The UK parcel sector generated almost £9 billion in revenue in 2015, with growth expected to increase by 15.6% in 2019 and is characterized by many independent players competing in an ‘everyone-delivers-everywhere’ culture leading to much replication of vehicle activity. With road space in urban centers being increasingly reallocated to pavement widening, bus and cycle lanes, there is growing interest in alternative solutions to the last-mile delivery problem. We make three contributions in this paper: firstly, through empirical analysis using carrier operational datasets, we quantify the characteristics of last-mile parcel operations and demonstrate the reliance placed on walking which can make up over 60% of the round time; secondly we introduce the concept of ‘portering’ where vans rendezvous with porters who operate within specific ‘patches’ to service consignees on-foot, potentially saving 86% in driving distance on some rounds; finally, we highlight the wider practical issues and optimization challenges associated with operating driving and portering rounds in inner urban areas