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Drottningarnas drottning : Jungfru Maria i svensk medeltida cisterciensisk predikan
En handskrift som en gång tillhörde Alvastra kloster, nu Uppsala Universitetsbibliotek C 37, innehåller en delvis kalendariskt ordnad predikosamling nedskriven i början av 1200-talet, utan kända paralleller. Artikeln beskriver samlingen och konstaterar att innehållet har både monastisk och folklig prägel. En möjlig slutsats är att en munk i Alvastra har sammanställt/författat predikningarna för at
The scientific and technological community in the Sustainable Development Goal process
Antenna design challenges and solutions for compact MIMO terminals
The design of antennas for compact multiple-input multiple-output (MIMO) terminals is a challenging feat, due to the space constraint and the physical structure of the terminal. The space constraint forces the antennas to be closely spaced, which degrades MIMO performance due to high signal correlation and low antenna efficiency. Moreover, the terminals are equipped with ground planes which furthe
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
Organizational discretion: identifying boundaries and reasoning in non-profit organizations’ relations with the public sector
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