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The use of millimeter wave communication for replacing wires in industrial environments has received much interest as part of the Industry 4.0 revolution. MM-wave communication may be used to have manufacturing entities communicate device to device in a decentralized private communication network, e.g. for letting autonomous mobile robots cooperate for improved efficiency and speed. Our objective in this paper is to understand how the device to device channel may be different from the characteristics reported in the literature on the infrastructure-based communication channel, as well as between cm- and near mm-wave. By transmitting and measuring a 5G synchronization signal burst, time-synchronized with the position of two moving robots, we characterize the large- and small-scale propagation characteristics as a function of the line of sight distance within a cluttered manufacturing space. Overall, we find only small differences between 3.8 and 26.4 GHz, however, with a clear indication that propagation at 26.4 GHz is more dominated by the geometric line of sight condition. For distances up to 35 m, path loss characteristics at the two frequencies are almost identical, close to free space propagation, and with shadowing decorrelation according to the (Gaussian) exponential decay model.

This work presents the analysis of a measurement campaign performed in a realistic two-hall industrial environment. In order to provide secure, reliable and high available Machine-to-Machine (M2M) communications in the mmWave band for Industrial Internet of Things (IIoT) mobile applications, a study of the physical propagation channel must be carried out. The analysis shows the high variability of the propagation channel depending on the Line-of-Sight (LoS) or Non Line-of-Sight (NLoS) condition, with path loss exponents ranging from 2.10 to 4.56. The mobility analysis demonstrates the high probability of beam switching if a threshold is not defined. By imposing this threshold, there is a decrease in the complexity of mobility management in exchange for a reduction in received power at the end user.

Estimating accurately the signal levels that a user equipment experiences along a movement route is a key step in the process of providing and guaranteeing the required service quality. Obtaining accurate location-specific estimations of the signal level is challenging due to its random variations. In this paper we investigate the use of aggregated measurements from multiple User Equipments (UE) to estimate the serving Reference Signal Received Power (RSRP) that the user will experience along a route. We use LTE measurements obtained in rural and urban areas from drive tests and analyze the dependence of data variability. Results show that the accuracy of data-driven estimation is impacted significantly by the variability in the underlying data due to UE orientation, UE characteristics and their immediate environment. With compensation for a subset of these effects the standard deviation of the estimation error can be lowered from an overall approximately 8 dB down to 4dB.

Decentralized cooperative resource allocation schemes for robotic swarms represents an alternative to infrastructure-based communications across different commercial, industrial and environmental protection use cases. The cooperative communication schemes, device sequential and group scheduling in [1], have shown superior performance in comparison to 5G NR sidelink mode 2, but have also shown performance issues due to signaling overhead and signaling induced failures. In this paper we introduce different techniques that reduce the failure probability of data packet transmissions and the packet inter-reception (PIR) time. We evaluate two techniques, respectively, of incremental redundancy using hybrid automatic repeat request and link adaptation by aggregation, as well as their combination for our decentralized cooperative resource allocation schemes and sidelink mode 2. Our results show that the introduced enhancements, allow to double the amount of supported swarm members while achieving four nines reliability when compared to the case where the same enhancements are applied to the sidelink mode 2.

ESR Journal This paper discusses the PhD education in a learning context with a specificfocus on the science and engineering discipline. In this context, a brieftheoretical reflection over the learning processes of forthcoming researchers isprovided, followed by an analysis of the competencies expected from the PhDstudy as a training process. Having this theoretical framework as a reference,various concepts and perspectives, that are important in the development of apromising researcher, are examined and explicated in the form of sevensuggested best practices. These include fundamental competencies likediligence and critical thinking, along with newer concepts like seeing the PhDeducation as a process instead of being a goal, and the need for collaborativelearning and peer network support.

The need for continuous safety improvements and increased operational efficiency is driving the mining industry through a transition towards large-scale automation of operations, i.e., “intelligent mines”. The technology promises to remove human operators from harsh or dangerous conditions and increase productivity, from extraction all the way to the delivery of a processed product to the customer. In this context, one of the key enablers is wireless connectivity since it allows mining equipment to be remotely monitored and controlled. Simply put, dependable wireless connectivity is essential for unmanned mine operations. Although voice and narrowband data radios have been used for years to support several types of mining activities, such as fleet management (dispatch) and telemetry, the use of automated equipment introduces a new set of connectivity requirements and poses a set of challenges in terms of network planning, management and optimization. For example, the data rates required to support unmanned equipment, e.g. a teleoperated bulldozer, shift from a few kilobits/second to megabits/second due to live video feeds. This traffic volume is well beyond the capabilities of Professional Mobile Radio narrowband systems and mandates the deployment of broadband systems. Furthermore, the (data) traffic requirements of a mine also vary in time as the fleet expands. Additionally, wireless networks are planned according to the characteristics of the scenario in which they will be deployed, but mines change by definition on a daily-basis. Therefore, a careful and continuous effort must be made to ensure the wireless network keeps up with the topographic and operational changes in order to provide the necessary network availability, reliability, capacity and coverage needed to support a new mining paradigm. By means of simulations, we analyze the effects on the wireless network along 7 years of constant topographic changes in an open-pit mine coupled with much higher data requirements. The authors also present a new network topology that is able to partially meet the requirements posed by mining automation and discuss the consequences of not providing connectivity for all applications. The work also discusses how the careful positioning of the heavy communications infrastructure (tall towers) from the early stages of the mine site project can make the provision of incremental capacity and coverage simpler.

Upcoming applications, such as autonomous vehicles, will pose strict requirements on the vehicular networks. In order to provide these new services reliably, an accurate understanding of propagation in the vehicular scenarios is needed. In this context, this paper presents a measurement-based evaluation of large vehicle shadowing at 5.8 GHz in V2X scenarios. The receiver antenna height is fixed to average vehicular height (1.5 m), while the transmitter antennas are located at different heights (1.5, 5, and 7 m) in order to investigate both V2V and V2I scenarios. A truck was used to obstruct the LOS between transmitter and receiver, and a large number of geometrical combinations of the scenario were explored. The statistical analysis of the measurement shows how in the V2V case, the experienced shadow levels are approximately 5 dB higher than in the V2I scenarios, where the shadow levels depend on the transmitter antenna height, reaching maximum values of 21-23 dB. The statistical analysis also shows that the differences in shadow level due to the non-symmetries of the obstacle truck are in the order of approximately 2 dB. A simple 3D ray-tracing simulation is validated against the measurements, showing a good match with a RMSE of 4.1 dB. Based on both measurements and ray-tracing data, a simple deterministic shadowing model, useful for implementation in system level simulators, is presented, as a first step towards a more dynamic and scalable shadowing model.

UEs which support simultaneous activity from Multiple Active SubscriberIdentities (Multi-SIM) has gained popularity within the last years. Such UEs are forced to discard data on one of the SIMs when both try to access the Radio Frequency (RF) interface simultaneously, creating gaps in the data transfer. The discarded data due to Multi-SIM gaps, along with channel errors, significantly increase the probability of high latency data subframes. High latency increases the probability of data subframes being discarded. In this paper we present an algorithm with which it is possible to decrease the probability of discarded data subframes due to high latency. The algorithm takes advantage of the fact that the connections of each SIMs are unaligned and therefore gaps will only cover some timeslots partially. In such a case, it is possible to recover data using existing error correction coding, if the amount of corrupted bits corresponds to the error correction capability of the code. We investigate the performance of the algorithm using a link level simulator in respect to KPIs; overall throughput, decrease in subframe loss probability, and block error rate. The algorithm is tested in three different radio conditions as they comprise different restrictions to the algorithm. We show how the algorithm significantly decreases the subframe loss probability due to Multi-SIM, without significant impact on the overall throughput.

5G is targeting a peak data rate in the order of 10Gb/s and at least 100Mb/s data rate is generally expected to be available everywhere. For fulfilling such 5G broadband targets, massive deployment of small cells is considered as one of the promising solutions. However, inter-cell interference leads to significant limitations on the network throughput in such deployments. In addition, network densification introduces difficulty in network deployment. This paper presents a study on the benefits of advanced receiver in a practical uncoordinated dense small cells deployment. Our aim is to show that advanced receivers can alleviate the need for detailed cell planning. To this end we adopt a hybrid simulation evaluation approach where propagation data are obtained from experimental analysis, and by which we analyse how MIMO constellation and network size impacts to the aim. The experimental data have been obtained using a software defined radio (SDR) testbed network with 12 testbed nodes, configured as either access point or user equipment. Each node features a 4 X 4$ or a 2 X 2 MIMO configuration. The results demonstrate that advanced receivers with a larger MIMO antenna configuration significantly improves the throughput performance in a practical dense small cells network due to the interference suppression capability. In addition, the results prove that the operators can rely on uncoordinated deployment of small cells, since the resulting interference can be suppressed by the advanced receiver processing with sufficiently capable MIMO antenna configuration.

To describe outcome and prognostic factors in a national Danish series of patients treated for salivary gland carcinoma. From three Danish nation-wide registries and supplementary patient records, 871 patients diagnosed with primary major or minor salivary gland carcinoma in the period from 1990 to 2005 were identified. A total of 796 (91%) histological specimens were revised according to the WHO 2005 classification. The median follow-up time was 78 months. Three hundred and thirty-four patients (38%) experienced recurrence. Crude survival, disease-specific survival and recurrence-free survival after 5 and 10 years were 66%, 76%, 64% and 51%, 69%, 58%, respectively. In multivariate analysis age, latency, stage, microscopic margins, vascular invasion and histological grade were all independent prognostic factors with regards to crude and disease-specific survival. Stage, microscopic margins, vascular invasion and histological grade were independent prognostic factors for recurrence-free survival. Age over 61 years, latency under 8 months, stage 3+4 disease, involved or close microscopic margins, vascular invasion and high histological grade are all independent prognostic factors with a negative impact on survival in salivary gland carcinoma patients. This knowledge can be helpful in guiding clinicians in daily work and choice of treatment across the large variety of salivary gland carcinoma subtypes.

Herein we present the synthesis and thermal stability studies of modified oligonucleotides containing an unlocked nucleic acid (UNA) terpyridine monomer. Incorporation of this monomer into both strands of a DNA duplex allowed reversible thermal stability modulation upon addition or withdrawal of divalent metal ions. A likely explanation of this phenomenon is interstrand complexation between two terpyridine units and a metal ion. This system could be useful in the development of nanoscale devices based on DNA hybridization.

Summary The aim of study The study presents a method of a reconstruction of the palatum after maxillectomy. This method is choosen in selected cases of malignant tumors of the maxilla. Material and methods The method is combined of preparation of the temporalis muscle flap and its dislocation it under arcus of zygoma into the oral cavity. The surface of the flap covered with temporal fascia is oriented into the oral cavity and has been stitched in the hole of the palatum. The surface of the flap covered with periostium is connected to postoperative cavity of the maxilla. The flap covered the palatum tightly divides oral cavity from postoperative cavity of the maxilla. The vascular pedicle of the flap, with deep temporal vessels supply blood for proper healing of the palatum. Oncologic control of the postoperative cavity is performed using imaging investigation (computer tomography, magnetic resonance). The loss of tissue in the temporal fossa is covered by temporal fossa fat or synthetic material. Results and conclusions The reconstruction method brings satisfactory functional result. The method allows to avoid using inconvenient prostheses – obturators of palatum – in patients after maxillectomy. Complications in this method as postoperative perforation of the palatum and necrosis of the muscle flap are rare – less than 5% cases.

BACKGROUND.: The benefit of a complementary fluorodeoxyglucose-positron emission tomography (FDG-PET) scan to standard workup for carcinoma of unknown primary (CUP) and metastatic neck lesions was prospectively studied. METHODS.: Sixty-seven patients underwent standardized diagnostic workup according to national guidelines including panendoscopies, multiple mucosal biopsies, and diagnostic CT/MRI scans. Median follow-up was 40 months (range, 2-65 months). RESULTS.: In 60 eligible patients, FDG-PET indicated a primary tumor or metastatic disease in 30 patients (50%). Additional investigations confirmed a primary tumor in 18 patients: hypopharynx in 5, oropharynx in 5, nasopharynx in 2, lung in 1, axilla in 1, bone in 1, rectum in 1, as well as multiple metastatic lesions from CUP in 2 patients. In retrospect, MRI was able to detect 1 of the PET-detected primaries, leading to an overall detection rate of PET of 29% in CUP. A therapeutic change of treatment was made in 25% as a consequence of FDG-PET. PET before panendoscopy demonstrated fewer false-positive pathological foci. CONCLUSION.: FDG-PET is a valuable tool in addition to conventional extensive workup in CUP and neck metastases. Consequently, FDG-PET is now recommended as an early diagnostic modality in the workup of these patients. (c) 2007 Wiley Periodicals, Inc. Head Neck, 2007.

Small Unmanned Aerial Vehicles (UAVs) are advancing their scope beyond military applications. Most of the work has been concentrated in employing multi-UAV systems in providing cellular services to enhance network coverage. However, little or no attention has been considered in serving moving hotspot conditions aka Place Time Capacity (PTC). In this paper, we explore a disparate way of employing multi-UAV systems by proposing a concept of Hovering Ad-Hoc Network (HANET) distinctively to solve PTC congestion using millimeter wave communication. We present a suitable architecture based on airborne HANET members as load balancing assistance to the primary network to offload user traffic to the nearby base station. The paper also presents a conceptual physical design of a HANET member to further endorse the proposed architecture. Small Unmanned Aerial Vehicles (UAVs) are advancing their scope beyond military applications. Most of the work has been concentrated in employing multi-UAV systems in providing cellular services to enhance network coverage. However, little or no attention has been considered in serving moving hotspot conditions aka Place Time Capacity (PTC). In this paper, we explore a disparate way of employing multi-UAV systems by proposing a concept of Hovering Ad-Hoc Network (HANET) distinctively to solve PTC congestion using millimeter wave communication. We present a suitable architecture based on airborne HANET members as load balancing assistance to the primary network to offload user traffic to the nearby base station. The paper also presents a conceptual physical design of a HANET member to further endorse the proposed architecture.

Head and neck paragangliomas (HNPGs) are rare tumours of neural crest origin that are benign in the majority of cases. In this article HNPGs are outlined with emphasis on genetic predisposition, diagnostics and counselling. The literature on HNPGs identified using PubMed is reviewed. Several susceptibility genes have been identified and hereditary mutations are detectable in 30% of the patients with HNPGs. Genetic analyses, guided by the family history and clinical findings, should be offered to all patients with HNPGs and at risk relatives.

It is often difficult to determine the actual site of origin of tumours originating in the sino-nasal region, and a uniform classification system that covers all tumours in this area is warranted. A retrospective series of 165 consecutive patients with sino-nasal carcinoma, treated and followed at the Aarhus University Hospital between 1963 and 1991, was evaluated and T-staged according to the Lederman classification. The 80 maxillary antrum carcinomas were also staged according to the UICC 1997 system. In univariate analysis, the UICC T-classification was prognostic for locoregional tumour control and disease-specific survival. However, when adjusted for covariates (gender and nodal involvement) in a multivariate analysis, the UICC classification was not a significant independent prognostic parameter. In contrast, the Lederman T-classification was prognostic both in univariate and multivariate analysis. The Lederman T-classification was more prognostic for locoregional control and disease-specific survival than the UICC TNM classification. In addition, the Lederman classification is easy to use and has a broader applicability as it covers all sites in the sino-nasal area.

Background Prognostic indicators that could assist in a more precise selection of patients with small oral carcinomas for differentiated therapy would be valuable. A significant fraction of patients with stage I disease have a relatively poor prognosis despite the small size of the tumor, but in general stage I tumors of the oral cavity have a favorable prognosis. Methods Seventy-eight patients with stage I (T1N0M0) oral squamous cell carcinoma from two different ENT departments were included in the study. The pretreatment biopsy specimens were graded according to the modified classification of Jakobsson et al. Eight individual parameters were recorded, four parameters describing the tumor cell population and four parameters describing the tumor/host interaction. Results The only significant prognostic parameter for disease-specific survival was “mode of invasion.” The histologic mean score was not significantly correlated to disease-specific or crude survival. Conclusions Mode of invasion is the most important histologic parameter when evaluating the prognosis. Histologic evaluation of small squamous cell carcinomas of the oral cavity may assist the design of a differentiated treatment strategy (eg, monotherapy vs combined treatment). © 2002 Wiley Periodicals, Inc. Head Neck 24: 656–660, 2002

Purpose : To investigate the prognostic value of T POT , S-phase time ( T S ), iododeoxyuridine (IdUrd) labelling index ( LI ) and DNA index with loco-regional tumour control as the end-point. Materials and methods : Iododeoxyuridine was given to 99 patients with squamous cell carcinomas of the head and neck before the start of radiotherapy. The analysis included FCM parameters ( LI , T S , T POT and DNA index, n =87) and LI determined by immunohistology (IHC, n =45). A hybrid T POT was determined by combining the FCM T S and the IHC LI ( n =45). In diploid tumours ( n =39), the FCM LI was underestimated and the FCM T POT was overestimated because the flow cytometer was unable to distinguish between tumour and normal cells. The `tumour LI ' was defined as the IHC LI or the FCM LI of aneuploid tumours when a biopsy for IHC evaluation was not available and similarly the `tumour T POT ' was determined by the hybrid T POT or the FCM T POT of aneuploid tumours ( n =63). Results : There was good agreement between the IHC LI and the FCM LI for aneuploid tumours, but there was disagreement for diploid tumours. The median tumour T POT was 4.1 days (range 0.6–19.5 days) and the median tumour LI was 12.9% (range 3.1–46.0%). In a univariate analysis there was no prediction of loco-regional tumour control by the LI , the T S or the T POT determined by either of the methods. T-classification, N-classification, clinical stage and tumour diameter were related with loco-regional tumour control, whereas clinical stage was the only parameter that yielded independent prognostic significance in a multivariate analysis. Conclusions : This study does not confirm the significant prognostic value of T POT as indicated in some previous reports. Larger clinical studies are needed to draw final conclusions.

Objectives:Resection of the maxilla requires adequate restoration of the maxilla structure to replace form and functions, especially vocal and eating functions. A host of reconstructive options are available to restore the maxilla, most of which include free flap reconstruction. The aim of this study was to clinically evaluate the use of pedicled temporalis flap for reconstruction of the maxilla and to assess patient quality of life.Methods:In the period 2000-2007, a total of 32 patients with malignant tumors of the maxilla were operated with immediate reconstruction of the maxilla using pedicled temporalis flap at the ear, nose, and throat (ENT) department, Aarhus University Hospital. Follow up was implemented in 2007. Twenty-seven of 28 patients alive at the time of follow up participated in the study. The patients were evaluated objectively as well as subjectively by answering the European Organisation for Research and Treatment of Cancer’s (EORTC’s) standard questionnaire concerning quality of life an...

In connection with the extension of the Copenhagen Metro system, architects and wireless operators met early in the design phase to plan the radio coverage inside the public areas of the metro transport system. Based on commonbest practice, an initial design for the antenna installations, and hence radio coverage, was proposed for a distributed antenna system in each of two distinctly different types of underground stations. In this paper, we describe the considerations for the design, and specifically the modeling and analysis of the underground stations by way of a commercial ray-tracing tool. Radio coverage results are given for different designs, including different number and types ofantennas, their configuration and placement, as well as the dependency on frequency and construction materials and presence of trains on the station platforms. In a practical case like this, compromises between stakeholders impact to the design and in some cases rule out options with better, more uniform, radio coverage. Also, given the constraints of the problem, common best practice leads to a conservative design which leaves a good margin for uncertainties and unaccounted propagation phenomena. In connection with the extension of the Copenhagen Metro system, architects and wireless operators met early in the design phase to plan the radio coverage inside the public areas of the metro transport system. Based on common best practice, an initial design for the antenna installations, and hence radio coverage, was proposed for a distributed antenna system in each of two distinctly different types of underground stations. In this paper, we describe the considerations for the design, and specifically the modelling and analysis of the underground stations by way of a commercial ray-tracing tool. Radio coverage results are given for different designs, including different number and types of antennas, their configuration and placement, as well as the dependency on frequency and construction materials and presence of trains on the station platforms. In a practical case like this, compromises between stakeholders impact to the design and in some cases rule out options with better, more uniform, radio coverage. Also, given the constraints of the problem, common best practice leads to a conservative design. It shows a good margin for uncertainties and unaccounted propagation phenomena by an analytical comparison.

The problem of spectrum scarcity in uncoordinated and/or heterogeneous wireless networks is the key aspect driving the research in the field of flexible management of frequency resources. In particular, distributed dynamic spectrum access (DSA) algorithms enable an efficient sharing of the available spectrum by nodes in a network, without centralized coordination. While proof-of-concept and statistical validation of such algorithms is typically achieved by using system level simulations, experimental activities are valuable contributions for the investigation of particular aspects such as a dynamic propagation environment, human presence impact and terminals mobility. This chapter focuses on the practical aspects related to the real world-experimentation with distributed DSA network algorithms over a testbed network. Challenges and solutions are extensively discussed, from the testbed design to the setup of experiments. A practical example of experimentation process with a DSA algorithm is also provided.

Thymine intermediate 17 has been synthesized on a multigram scale (50 g, 70 mmol) from starting sugar 1 in 15 steps in an overall yield of 73%, with only 5 purification steps. The key thymine intermediate 18 was obtained from 17 in a single step in 96% yield, whereas the key 5-methylcytosine intermediate 20 was obtained from 17 in 2 steps in 58% yield. This highly efficient large scale route necessitates only 2 and 3 novel steps to obtain N2′-functionalized thymine and 5-methylcytosine amino-LNA phosphoramidites from these key intermediates, respectively.

The aim of this study was to assess the potential effect of tobacco and alcohol consumption on the histological differentiation of oral squamous cell carcinomas in 161 consecutive patients. The patients were included in a prospective study to secure valid data on tobacco and alcohol consumption. The histopathological grading system included eight morphological qualities describing both the tumour cell population and the interaction between tumour and host. A mean histological score was calculated as the arithmetic mean of the scored individual morphological parameters. Tobacco consumption, as opposed to alcohol consumption, was shown to be significantly correlated with the mean histological score (P = 0.0009), and with the four morphological qualities describing the tumour cell population: pattern (P = 0.0044), cytoplasmic differentiation (P = 0.0008), nuclear differentiation (P = 0.0054) and mitosis (P = 0.0001). Thus, tobacco consumption seems to cause the tumour cells of oral squamous cell carcinomas to undergo a more pronounced dedifferentiation which makes them more aggressive. This effect is enhanced with increasing exposure to tobacco smoke.

Delay in diagnosis was recorded prospectively in 167 patients with an oral squamous cell carcinoma. The median total delay was 4 months of which two-thirds was patient delay. The corrected survival did not correlate with the total delay. The patient delay was not significantly correlated with tumour or patient factors and the unreliable nature of patient delay information makes such data clinically unusable. In contrast, the professional delay correlated significantly with some of these factors. The delay was longer for women than for men and the older the patient, the longer the delay. The professional delay was longest in patients with small tumours. Thus, registration of the professional delay provides information to be used to improve the diagnostic efficiency of the health care system.

A population-based case-control study was designed to examine if the risk of developing intra-oral squamous-cell carcinoma in Denmark was associated with occupation, marital status, residence, dental status, and exposure to coffee, tea, tobacco, and alcohol. Cases consisted of 161 consecutively-admitted incident patients with histologically verified, primary, intra-oral squamous-cell carcinoma treated at the Aarhus University Hospital from January 1986 to November 1990. For each case, three controls of the same gender and age were selected randomly from among nonhospitalized residents in the hospital's catchment area (some 1.4 m inhabitants). Four hundred of the selected 483 controls participated in the study. Risk was associated significantly with marital status, residence, dental status, alcohol consumption, and exposure to tobacco. When correcting for tobacco and alcohol consumption, only marital status and dental status remained significant. The association between risk and marital status was particularly prominent among divorced compared with married persons (odds ratio [OR] = 2.3, 95 percent confidence interval [CI] = 1.1-4.6). Persons with less than five teeth had an OR of 2.4 (CI 1.3-4.1) compared with persons with 15 or more teeth. Tobacco and alcohol exposure were the strongest individual risk-indicators in both lifetime and current consumption estimates, and their composite effect was particularly strong. Compared with nonusers, OR for tobacco (> 20 g/d) adjusted for alcohol = 5.8 (CI = 3.1-10.9); OR for alcohol (> 5 drinks/d) adjusted for tobacco = 8.4 (CI = 4.0-17.6). The OR for heavy users of tobacco and alcohol (> 20 g tobacco/d and > 5 drinks/d) was 80.7 (CI = 21.8-298.8). These results confirm that tobacco and alcohol contribute significantly to the risk of developing oral cancer. There were no significant differences between the risk estimates for the two genders or young and old persons. Two simulation studies indicate that the observed risk associated with tobacco and alcohol consumption cannot be explained reasonably by a high consumption among the 83 nonrespondents.

Significant tumour progression was observed during waiting time for treatment of head and neck cancer. To reduce waiting times, a Danish national policy of fast track accelerated clinical pathways was introduced in 2007. This study describes changes in waiting time and the potential influence of fast track by comparing waiting times in 2010 to 2002 and 1992.Charts of all new patients diagnosed with squamous cell carcinoma of the oral cavity, pharynx and larynx at the five Danish head and neck oncology centres from January to April 2010 (n=253) were reviewed and compared to similar data from 2002 (n=211) and 1992 (n=168).The median time to diagnosis was 13 days (2010) versus 17 days (2002; p0.001) and 20 days (1992; p0.001). Median days from diagnosis to treatment start were 25 (2010) versus 47 (2002; p0.001) and 31 (1992; p0.001). Total pre-treatment time was median 41 days in 2010 versus 69 days (2002) (p0.001) and 50 days (1992; p0.001). Significantly more diagnostic imaging was done in 2010 compared to 2002 and 1992. When compared to current fast track standards the adherence to diagnosis improved slightly from 47% (1992) to 51% (2002) and 64% (2010); waiting time for radiotherapy was within standards for 7%, 1% and 22% of cases, respectively; waiting time for surgery was within standards for 17%, 22% and 48%, respectively.The study showed a significant reduction in delay of diagnosis and treatment of head and neck cancer in 2010, but still less than half of all patients start treatment within the current standards.

Background. Fast and accurate work-up is crucial to ensure the best possible treatment and prognosis for patients with head and neck cancer. The presence or absence of neck lymph node metastases is important for the prognosis and the choice of treatment. Clinical lymph node (N)-staging is done by palpation and diagnostic imaging of the neck. We investigated the current practice of the initial radiological work-up of patients with oral squamous cell carcinomas (OSCC) in the Nordic countries. Methods. A questionnaire regarding the availability and use of guidelines and imaging modalities for radiological N-staging in OSCC was distributed to 21 Head and Neck centres in Denmark (n = 4), Finland (n = 5), Iceland (n = 1), Norway (n = 4) and Sweden (n = 7). We also asked for a description of the radiological criteria for determining the lymph nodes as clinical positive (cN+) or negative (cN0). Results. All 21 Head and Neck centres responded to the questionnaire. Denmark and Finland have national guidelines, while Norway and Sweden have local or regional guidelines. Seventeen of the 19 centres with available guidelines recommended computed tomography (CT) of the cN0 neck. The waiting time may influence the imaging modalities used. Lymph node size was the most commonly used criteria for radiological cN+, but the cut-off measures vary from 0.8 to 2.0 cm. Conclusion. Overall, CT is the most commonly recommended and used imaging modality for OSCC. Despite availability of national guidelines the type and number of radiological examinations vary between centres within a country, but the implementation of a fast-track programme may facilitate fast access to imaging. The absence of uniform criteria for determining the lymph nodes of the neck as cN+ complicates the comparison of the accuracy of the imaging modalities. Well-defined radiological strategies and criteria are needed to optimise the radiological work-up in OSCC.

However, Cross Layer also carries a risk due to possibly unexpected and undesired effects. In this chapter, the authors provide architecture designers with a set of guidelines synthesized from an analysis of the state of the art, but enriched with the perspective of the development of future generations of communication systems such as Cognitive Radio. Wireless communications are a fast grown part of the telecommunication market. While new types of traffic and challenges related to the wireless medium are appearing, the methodologies for designing system architectures are substantially remaining the same. Under the increasing pressure of market, users, and physical medium issues, designers are in the need for new approaches.Cross Layer becomes than a handy solution for coping with such problems. In fact, it allows both tighter optimizations of the existing functionalities, and the introduction of new ones, that do not fit within the traditional protocol stack design methodology. However, Cross Layer also carries a risk due to possibly unexpected and undesired effects. In this chapter we want to provide architecture designers with a set of tools and recommendations synthesized from an analysis of the state of art, but enriched with the perspective of the development of future generations of communication systems such as Cognitive Radio.

In a well-defined group of 161 consecutive patients with intra-oral squamous cell carcinoma we found 23 non-users of tobacco and alcohol. The non-users in this prospective study were compared with users of tobacco and alcohol in the study, and to a sex- and age-matched control group drawn at random from the Danish Central Citizenry Registration. The users in the patient group represented a significantly higher number than in the control group. As to non-users, women represented a higher number in the patient group compared with the control group. Among users and non-users differences were found in the location of the primary tumour and in the degree of differentiation of the tumour. Haematological status and liver function parameters were different in the two groups. There was no difference in dental or oral hygiene status or risk occupation among the groups. The stage and the course of the disease (corrected survival) showed only insignificant differences. The non-user group contained especially older women, and only one of them had anaemia.

In this paper we discuss the implementation of a Single Carrier Frequency Division Multiple Access (SC-FDMA) transceiver running over the Universal Software Radio Peripheral 2 (USRP2). SC-FDMA is the air interface which has been selected for the uplink in the latest Long Term Evolution (LTE) standard. In this paper we derive a AWGN channel model for SC-FDMA transmission, which is useful for benchmarking experimental results. In our implementation, we deal with signal scaling, qualization and partial synchronization to realize SCFDMA transmission over a noisy channel at rates up to 5.184 Mbit/s. Experimental results on the Bit Error Rate (BER) versus Signal-to-Noise Ratio (SNR) are presented and compared to theoretical and simulated performance.