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Angle and polarization diversity in compact dual-antenna terminals with chassis excitation

For multiple antennas on a compact terminal chassis, chassis current excitation can severely increase mutual coupling between the antennas. This is because the same characteristic mode of the chassis may be strongly excited by more than one antenna. Here, we propose to use one antenna that exploits chassis excitation and introduce a second antenna that minimizes chassis excitation. In this way, an

Experimental evaluation of MIMO terminal antenna configurations in noise- and interference-limited urban scenarios

In this paper, we compare capacity performances of three terminal dual-antenna configurations at 2.65 GHz based on extensive 2 by 2 multiple-input multiple-output (MIMO) channel measurements in an urban macrocellular environment. Both noise- and interference-limited scenarios are investigated. Our results show that, on average over the measurement route, the capacity performance is mainly determin

Impact of current localization on the performance of compact MIMO antennas

In this paper, we study the influence of current localization on the isolation between two antennas in a compact terminal setting. The two antennas are chosen to be a monopole and a PIFA. The degree of current localization is controlled by the permittivity value of the PIFA’s dielectric loading. Both lossless and lossy cases are simulated in order to ascertain the underlying performance impact fro

On simplifying WINNER II channel model for MIMO OTA performance evaluation

The development of MIMO over-the-air (OTA) test methodology is an ongoing activity in 3GPP RAN4, CTIA and EU COST Action 2100. In this paper, the focus is on the anechoic chamber approach, which uses a uniform circular array of probe antennas to replicate directional channels for the device-under- test at the array center. In particular, we study in simulation the complexity requirements of implem

Performance of cooperative MIMO based on measured urban channel data

We study the potential benefits of cooperative multiple-input multiple-output signaling from multiple coherent base stations with one or more mobile stations in an urban macrocellular environment. The analysis uses novel and fully coherent measurements of the channel from three base stations to a single mobile station equipped with four antennas. The observed channels are used to explore the gains

Optimal multiple antenna design for compact MIMO terminals with ground plane excitation

The compactness of mobile terminals complicates the design of multiple antennas, since coupling among the antennas increases when they are placed in proximity of one another. While it is possible to mitigate coupling between closely spaced antennas, a tradeoff in bandwidth is required. In this paper, we highlight ground plane excitation as an additional dimension to consider in the design of multi

Identification of a Catalytically Highly Active Surface Phase for CO Oxidation over PtRh Nanoparticles under Operando Reaction Conditions

Pt-Rh alloy nanoparticles on oxide supports are widely employed in heterogeneous catalysis with applications ranging from automotive exhaust control to energy conversion. To improve catalyst performance, an atomic-scale correlation of the nanoparticle surface structure with its catalytic activity under industrially relevant operando conditions is essential. Here, we present x-ray diffraction data

Gut Feelings - From Brain to Gut and from Lumen to Gut

Part 1: From Brain to GutThe brain is an organ with a high energy requirement. To meet this demand, the brain needs a continuous and well-regulated blood supply. In situations where the brain, or parts of the brain, does not receive sufficient blood flow injury arise. This condition, commonly known as cerebral ischemia, is prevalent in today's society. In 2015, more than 6 million people died from

Small spatial variability in methane emission measured from a wet patterned boreal bog

We measured methane fluxes of a patterned bog situated in Siikaneva in southern Finland from six different plant community types in three growing seasons (2012-2014) using the static chamber method with chamber exposure of 35 min. A mixed-effects model was applied to quantify the effect of the controlling factors on the methane flux.The plant community types differed from each other in their water

High burden of atopy in immigrant families in substandard apartments in Sweden – on the contribution of bad housing to poor health in vulnerable populations

Background: Atopic disorders are a global concern. Studies in migrant populations can illuminate the interplay of genetic and environmental factors. Exposures related to bad housing (indoor dampness, mould growth, crowding etc.) are likely to play a role in how socioeconomic inequalities can turn into health disparities for disadvantaged populations. The sizable immigrant population living in very

History meets palaeoscience : Consilience and collaboration in studying past societal responses to environmental change

History and archaeology have a well-established engagement with issues of premodern societal development and the interaction between physical and cultural environments; together, they offer a holistic view that can generate insights into the nature of cultural resilience and adaptation, as well as responses to catastrophe. Grasping the challenges that climate change presents and evolving appropria

Clinical implications of CT findings in mesenteric venous thrombosis at admission

Purpose: The main aim of this study was to evaluate the association of computed tomography (CT) findings at admission and bowel resection rate in patients with mesenteric venous thrombosis (MVT). It was hypothesized that abnormal intestinal findings on CT were associated with a higher bowel resection rate. Methods: Retrospective study of MVT patients treated between 2004 and 2017. CT images at adm

Neurosurgical untethering with or without syrinx drainage results in high patient satisfaction and favorable clinical outcome in post-traumatic myelopathy patients

Study design: Retrospective data collection and patient-reported outcome measures. Objectives: To investigate surgical outcome, complications, and patient satisfaction in patients with chronic SCI and symptomatic post-traumatic progressive myelopathy (PPM) who underwent neurosurgical untethering and/or spinal cord cyst drainage with the aim of preventing further neurological deterioration. Setting

Overweight, obesity and the risk of LADA : results from a Swedish case–control study and the Norwegian HUNT Study

Aims/hypothesis: Excessive weight is a risk factor for type 2 diabetes, but its role in the promotion of autoimmune diabetes is not clear. We investigated the risk of latent autoimmune diabetes in adults (LADA) in relation to overweight/obesity in two large population-based studies. Methods: Analyses were based on incident cases of LADA (n = 425) and type 2 diabetes (n = 1420), and 1704 randomly s

Career preparation in doctoral education at the departmental level

Traditionally, doctoral education is designed to train students to become skilled researchers in their respective disciplines. In many cases, however, doctoral graduates find themselves ill-prepared for their career choices. In this paper, we adopt a systematic approach to study the career preparation aspect of doctoral study in our home department. Our findings reveal several shortcomings in the

Development and external validation of a risk-prediction model to predict 5-year overall survival in advanced larynx cancer

Objectives/Hypothesis: TNM-classification inadequately estimates patient-specific overall survival (OS). We aimed to improve this by developing a risk-prediction model for patients with advanced larynx cancer. Study Design: Cohort study. Methods: We developed a risk prediction model to estimate the 5-year OS rate based on a cohort of 3,442 patients with T3T4N0N+M0 larynx cancer. The model was inte

Brain pericyte activation occurs early in Huntington's disease

Microvascular changes have recently been described for several neurodegenerative disorders, including Huntington's disease (HD). HD is characterized by a progressive neuronal cell loss due to a mutation in the Huntingtin gene. However, the temporal and spatial microvascular alterations in HD remain unclear. Also, knowledge on the implication of pericytes in HD pathology is still sparse and existin

Hormonal factors and pancreatic cancer risk in women : The Malmö Diet and Cancer Study

The incidence of pancreatic cancer is leveling between sexes. Smoking, high age and heredity are established risk factors, but evidence regarding the influence of hormonal factors is unclear. In this study, we investigated the associations of reproductive factors, use of oral contraceptives (OC) and hormone replacement therapy (HRT) with pancreatic cancer risk in the Malmö Diet and Cancer Study, a