Purpose
The purpose of this study was to investigate if a 2-year intervention with a minimal resource fracture liaison service (FLS) was associated with increased investigation and medical treatment ...and if treatment was related to reduced re-fracture risk.
Methods
The FLS started in 2013 using existing secretaries (without an FLS coordinator) at the emergency department and orthopaedic wards to identify risk patients. All patients older than 50 years of age with a fractured hip, vertebra, shoulder, wrist or pelvis were followed during 2013–2014 (
n
= 2713) and compared with their historic counterparts in 2011–2012 (
n
= 2616) at the same hospital. Re-fractures were X-ray verified. A time-dependent adjusted (for age, sex, previous fracture, index fracture type, prevalent treatment, comorbidity and secondary osteoporosis) Cox model was used.
Results
The minimal resource FLS increased the proportion of DXA-investigated patients after fracture from 7.6 to 39.6 % (
p
< 0.001) and the treatment rate after fracture from 12.6 to 31.8 %, which is well in line with FLS types using the conventional coordinator model. Treated patients had a 51 % lower risk of any re-fracture than untreated patients (HR 0.49, 95 % CI 0.37–0.65
p
< 0.001).
Conclusions
We found that our minimal resource FLS was effective in increasing investigation and treatment, in line with conventional coordinator-based services, and that treated patients had a 51 % reduced risk of new fractures, indicating that also non-coordinator based fracture liaison services can improve secondary prevention of fractures.
The HERSCHEL detector consists of a set of scintillating counters, designed to increase the coverage of the LHCb experiment in the high-rapidity regions on either side of the main spectrometer. The ...new detector improves the capabilities of LHCb for studies of diffractive interactions, most notably Central Exclusive Production. In this paper the construction, installation, commissioning, and performance of HERSCHEL are presented.
The readout strategy of the LHCb experiment is based on complete event readout at 1MHz. A set of 320 sub-detector readout boards transmit event fragments at total rate of 24.6MHz at a bandwidth usage ...of up to 70GB/s over a commercial switching network based on Gigabit Ethernet to a distributed event building and high-level trigger processing farm with 1470 individual multi-core computer nodes. In the original specifications, the readout was based on a pure push protocol. This paper describes the proposal, implementation, and experience of a non-conventional mixture of a push and a pull protocol, akin to credit-based flow control. An FPGA-based central master module, partly operating at the LHC bunch clock frequency of 40.08MHz and partly at a double clock speed, is in charge of the entire trigger and readout control from the front-end electronics up to the high-level trigger farm. One FPGA is dedicated to controlling the event fragment packing in the readout boards, the assignment of the farm node destination for each event, and controls the farm load based on an asynchronous pull mechanism from each farm node. This dynamic readout scheme relies on generic event requests and the concept of node credit allowing load control and trigger rate regulation as a function of the global farm load. It also allows the vital task of fast central monitoring and automatic recovery in-flight of failing nodes while maintaining dead-time and event loss at a minimum.
This paper demonstrates the strength and suitability of implementing this real-time task for a very large distributed system in an FPGA where no random delays are introduced, and where extreme reliability and accurate event accounting are fundamental requirements. It was in use during the entire commissioning phase of LHCb and has been in faultless operation during the first two years of physics luminosity data taking.
Performance parameters of a composite detection module of Spaghetti type Calorimeter (SPACAL), which is considered for the inner part of the future LHCb Electromagnetic Calorimeter (ECAL) in Upgrade ...Phase 2, are simulated using GEANT4 software supported by analytical calculations. The accuracy of the timestamp is estimated in both the front and back sections of the composite detector, whereas the energy resolution is estimated for the total signal from the front and back sections of the detector. The rise time of the scintillation response used in the calculations is reconstructed using the results of the coincidence time resolution measurements with annihilation γ-quanta. The time and energy resolutions with PMT readout are compared for Ce-doped garnet- and oxyorthosilicate-type single crystal scintillators without codoping and codoped with aliovalent impurities.
The beam dump facility (BDF) project is a proposed general-purpose facility at CERN, dedicated to beam dump and fixed target experiments. In its initial phase, the facility is foreseen to be ...exploited by the Search for Hidden Particles Experiment. Physics requirements call for a pulsed400GeV/cproton beam as well as the highest possible number of protons on target each year of operation (4.0×1019/year), in order to search for feebly interacting particles. The target/dump assembly lies at the heart of the facility, with the aim of safely absorbing the full high intensity Super Proton Synchrotron beam, while maximizing the production of charmed and beauty mesons. High-Z materials are required for the target/dump, in order to have the shortest possible absorber and reduce muon background for the downstream experiment. The design of the production target is one of the most challenging aspects of the facility design, due to the high energy and power density deposition that are reached during operation, and the resulting thermomechanical loads. The nature of the beam pulse induces very high temperature excursions between pulses (up to100°C), leading to considerable thermally induced stresses and long-term fatigue considerations. The high average power deposited on target (305 kW) creates a challenge for heat removal. During the BDF facility comprehensive design study, launched by CERN in 2016, extensive studies have been carried out in order to define and assess the target assembly design. These studies are described in the present contribution, which details the proposed design of the BDF production target, as well as the material selection process and the optimization of the target configuration and beam dilution. One of the specific challenges and novelty of this work is the need to consider new target materials, such as a molybdenum alloy as core absorbing material and Ta2.5W as cladding. Thermostructural and fluid dynamics calculations have been performed to evaluate the reliability of the target and its cooling system under beam operation. In the framework of the target comprehensive design, a preliminary mechanical design of the full target assembly has also been carried out, assessing the feasibility of the whole target system.
The beam dump facility (BDF) is a project for a new facility at CERN dedicated to high intensity beam dump and fixed target experiments. Currently in its design phase, the first aim of the facility ...is to search for light dark matter and hidden sector models with the Search for Hidden Particles (SHiP) experiment. At the core of the facility sits a dense target/dump, whose function is to absorb safely the400GeV/cSuper Proton Synchrotron (SPS) beam and to maximize the production of charm and beauty mesons. An average power of 300 kW will be deposited on the target, which will be subjected to unprecedented conditions in terms of temperature, structural loads and irradiation. In order to provide a representative validation of the target design, a prototype target has been designed, manufactured, and tested under the SPS fixed-target proton beam during 2018, up to an average beam power of 50 kW, corresponding to 350 kJ per pulse. The present contribution details the target prototype design and experimental setup, as well as a first evaluation of the measurements performed during beam irradiation. The analysis of the collected data suggests that a representative reproduction of the operational conditions of the beam dump facility target was achieved during the prototype tests, which will be complemented by a postirradiation examination campaign during 2020.
This paper addresses several aspects of implementing a remote control system for a large number of electronics boards in order to perform remote Field Programmable Gate Array (FPGA) programming, ...hardware configuration, data register access, and monitoring, as well as interfacing it to an expert system. The paper presents a common strategy for the representation of the boards in the abstraction layer of the control system, and generic communication protocols for the access to the board resources. In addition, an implementation is proposed in which the mapping between the functional parameters and the physical registers of the different boards is represented by descriptors in the board representation such that the translation can be handled automatically by a generic translation manager. Using the Distributed Information Management (DIM) package for the control communication with the boards, and the industry SCADA system PVSS II from ETM, a complete control system has been built for the Timing and Fast Control (TFC) system of the LHCb experiment at CERN. It has been in use during the entire prototyping of the TFC system and the developments of the LHCb sub-detector electronics, and is now installed in the online system of the final experiment.
The LHCb experiment has proposed an upgrade towards a full 40 MHz readout system in order to run between five and ten times its initial design luminosity. The entire readout architecture will be ...upgraded in order to cope with higher sub-detector occupancies, higher rate and higher network load. In this paper, we describe the architecture, functionalities and a first hardware implementation of a new fast Readout Control system for the LHCb upgrade, which will be entirely based on FPGAs and bi-directional links. We also outline the real-time implementations of the new Readout Control system, together with solutions on how to handle the synchronous distribution of timing and synchronous information to the complex upgraded LHCb readout architecture. One section will also be dedicated to the control and usage of the newly developed CERN GBT chipset to transmit fast and slow control commands to the upgraded LHCb Front-End electronics. At the end, we outline the plans for the deployment of the system in the global LHCb upgrade readout architecture.
The beam-gas vertex (BGV) detector is an innovative instrument measuring noninvasively the transverse beam size in the Large Hadron Collider (LHC) using reconstructed tracks from beam-gas ...interactions. The BGV detector was installed in 2016 as part of the R&D for the High-Luminosity LHC project. It allows beam size measurements throughout the LHC acceleration cycle with high-intensity physics beams. A precision better than 2% with an integration time of less than 30 s is obtained on the average beam size measured, while the transverse size of individual proton bunches is measured with a resolution of 5% within 5 min. Particles emerging from beam-gas interactions in a specially developed gas volume along the beam direction are recorded by two tracking stations made of scintillating fibers. A scintillator trigger system selects, on-line, events with tracks originating from the interaction region. All the detector elements are located outside the beam vacuum pipe to simplify the design and minimize interference with the accelerated particle beam. The beam size measurement results presented here are based on the correlation between tracks originating from the same beam-gas interaction vertex.
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