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Adaptations in muscle physiology due to long-term physical training have been monitored using various methods: ranging from invasive techniques, such as biopsy, to less invasive approaches, such as electromyography (EMG), to various quantitative magnetic resonance imaging (qMRI) parameters. Typically, these latter parameters are assessed immediately after exercise. In contrast, this work assesses such adaptations in a set of qMRI parameters obtained at rest in the lumbar spine muscles of volunteers. To this end, we developed a multiparametric measurement protocol to extract quantitative values of (water) T2, fat fraction, T1, and Intra Voxel Incoherent Motion (IVIM) diffusion parameters in the lumbar back muscle. The protocol was applied to 31 healthy subjects divided into three differently trained cohorts: two groups of athletes (endurance athletes and powerlifters) and a control group with a sedentary lifestyle. Significant differences in muscle water T2, fat fraction, and pseudo-diffusion coefficient linked to microcirculatory blood flow in muscle tissue were found between the trained and untrained cohorts. At the same time, diffusion coefficients (resolved along different directions) provided additional differentiation between the two groups of athletes. Specifically, the strength-trained athletes showed lower axial and higher radial diffusion components compared to the endurance-trained cohort, which may indicate muscle hypertrophy. In conclusion, utilizing multiparametric information revealed new insights into the potential of quantitative MR parameters to detect and quantify long-term effects associated with training in differently trained cohorts, even at rest.

Introduction: This work aimed to develop a novel multipurpose device for guided knee flexion-extension, both passively using a motorized pneumatic system and actively (muscle-driven) with the joint unloaded or loaded during dynamic MRI. Secondary objectives were to characterize the participant experience during device use, and present preliminary dynamic MRI data to demonstrate the different device capabilities. Material and methods: Self-reported outcomes were used to characterize the pain, physical exertion and discomfort levels experienced by 10 healthy male participants during four different active knee motion and loading protocols using the novel device. Knee angular data were recorded during the protocols to determine the maximum knee range of motion achievable. Dynamic MRI was acquired for three healthy volunteers during passive, unloaded knee motion using 2D Cartesian TSE, 2D radial GRE and 3D UTE sequences; and during active, unloaded and loaded knee motion using 2D radial GRE imaging. Because of the different MRI sequences used, spatial resolution was inherently lower for active knee motion than for passive motion acquisitions. Results: Depending on the protocol, some participants reported slight pain, mild discomfort and varying levels of physical exertion. On average, participants achieved ∼40° of knee flexion; loaded conditions can create knee moments up to 27 Nm. High quality imaging data were obtained during different motion and loading conditions. Dynamic 3D data allowed to retrospectively extract arbitrarily oriented slices. Conclusion: A novel multipurpose device for guided, physiologically relevant knee motion and loading during dynamic MRI was developed. Device use was well tolerated and suitable for acquiring high quality images during different motion and loading conditions. Different bone positions between loaded and unloaded conditions were likely due to out-of-plane motion, particularly because image registration was not performed. Ultimately, this device could be used to advance our understanding of physiological and pathological joint mechanics.

IntroductionChronic health effects following acute COVID-19 are increasingly observed as the pandemic continues and are grouped under long COVID. Although the acute course of the COVID disease is often milder, long COVID also affects children and adolescents. As the symptoms present in Long-COVID often seem to be non-specific and not limited to organ systems, clarification of the causes and the creation of a meaningful, efficient and targeted diagnostic algorithm is urgently needed.MethodsTherefore, in this prospective observational study, we examined 30 children with long COVID using lung ultrasound and compared the results with those of 15 lung-healthy children.ResultsIn our study, no significant difference was found between the two groups in the morphological criteria of lung ultrasound of the pleura or pleural lung structures. There was no significant correlation between the lung ultrasound findings and clinical Data.DiscussionOur findings are congruent with the current, albeit sparse, data. It is possible that the causes of persistent thoracic symptoms in long COVID might be more likely to be present in functional examinations, but not morphologically imageable. Nonspecific symptoms do not appear to be due to changes in the lung parenchyma. In conclusion, lung ultrasound alone and without baseline in acute disease is not suitable as a standard in the follow-up of long COVID patients. Further investigations on the morphological and functional changes in patient with long COVID is needed.

Purpose: Prospectively-gated Cartesian 4D-flow (referred to as Cartesian-4D-flow) imaging suffers from long TE and intensified flow-related intravoxel-dephasing especially in preclinical ultra-high field MRI. The ultra-short-echo (UTE) 4D-flow technique can resolve the signal loss in higher-order blood flows; however, the long scan time of the high resolution UTE-4D-flow is considered as a disadvantage for preclinical imaging. To compensate for prolonged acquisitions, an accelerated k0-navigated golden-angle center-out stack-of-stars 4D-flow sequence (referred to as SoS-4D-flow) was implemented at 9.4T and the results were compared to conventional Cartesian-4D-flow mapping in-vitro and in-vivo.Methods: The study was conducted in three steps (A) In-vitro evaluation in a static phantom: to quantify the background velocity bias. (B) In-vitro evaluation in a flowing water phantom: to investigate the effects of polar undersampling (US) on the measured velocities and to compare the spatial velocity profiles between both sequences. (C) In-vivo evaluations: 24 C57BL/6 mice were measured by SoS-4D-flow (n = 14) and Cartesian-4D-flow (n = 10). The peak systolic velocity in the ascending aorta and the background velocity in the anterior chest wall were analyzed for both techniques and were compared to each other.Results: According to the in-vitro analysis, the background velocity bias was significantly lower in SoS-4D-flow than in Cartesian-4D-flow (p < 0.05). Polar US in SoS-4D-flow influenced neither the measured velocity values nor the spatial velocity profiles in comparison to Cartesian-4D-flow. The in-vivo analysis showed significantly higher diastolic velocities in Cartesian-4D-flow than in SoS-4D-flow (p < 0.05). A systemic background bias was observed in the Cartesian velocity maps which influenced their streamline directions and magnitudes.Conclusion: The results of our study showed that at 9.4T SoS-4D-flow provided higher accuracy in slow flow imaging than Cartesian-4D-flow, while the same measurement time could be achieved.

The ATR vowel harmony patterns observed in Kinande have received persistent attention for their combination of stem control and dominance, as well as less familiar phenomena such as dominance reversal and cross-word harmony. This paper provides a Syntagmatic Correspondence analysis of the Kinande vowel harmony system and demonstrates that it straightforwardly accounts for the intricate interaction of featural, directional and morpho-prosodic domain restrictions that define the occurring harmony patterns. The analysis obviates an appeal to dominance reversal, and cross-word harmony is shown to be phonological, not phonetic (contra Archangeli & Pulleyblank 2002; Kaisse 2019), yielding to a non-stratal analysis in the approach adopted. The analysis thus provides additional evidence for incorporating directionality into the formalization of Syntagmatic Correspondence constraints and for morpho-prosodic domain limitations on these and other OT constraints.

This paper argues for the Coda Condition to be a universal set of violable constraints on the basis of new vowel epenthesis data from Persian (Farsi). Vowel insertion in L2 phonology, loanwords, and nonce-words is driven by a strict ban on consonant clusters in syllable onsets. The choice between anaptyxis and prothesis is determined by the Coda Condition. As there is no detectable evidence for a coda condition in the existing Persian lexicon, it would be impossible for speakers of Persian to have acquired the Coda Condition as part of the L1 acquisition process. Moreover, this study contradicts two claims made in the literature: first, that anaptyxis/prothesis splits are always caused by the Syllable Contact Law, and second, that all coda condition effects can be reanalysed with positional faithfulness. Going beyond the Persian data, the paper argues for a formulation of the Coda Condition as positional licensing rather than simple markedness in interaction with positional faithfulness.

(1) Background: Pulmonary arterial hypertension (PAH) is a serious condition that is associated with many cardiopulmonary diseases. Invasive right heart catheterization (RHC) is currently the only method for the definitive diagnosis and follow-up of PAH. In this study, we sought a non-invasive hemodynamic biomarker for the diagnosis of PAH. (2) Methods: We applied prospectively respiratory and cardiac gated 4D-flow MRI at a 9.4T preclinical scanner on three different groups of Sprague Dawley rats: baseline (n = 11), moderate PAH (n = 8), and severe PAH (n = 8). The pressure gradients as well as the velocity values were analyzed from 4D-flow data and correlated with lung histology. (3) Results: The pressure gradient between the pulmonary artery and vein on the unilateral side as well as the time-averaged mean velocity values of the small pulmonary arteries were capable of distinguishing not only between baseline and severe PAH, but also between the moderate and severe stages of the disease. (4) Conclusions: The current preclinical study suggests the pulmonary arteriovenous pressure gradient and the time-averaged mean velocity as potential biomarkers to diagnose PAH.

Two traditional approaches to the study of Japan in the West—comparison and a focus on connections—both fundamentally regard Japanese culture as a distinct entity. A less essentialist and more fruitful approach might be to see Japanese culture as the product of responses to global developments and conjunctures that the West has also been subjected to. Classical modernization theory, the multiple modernities approach, and, more recently, the Great Divergence debate have each in their own way situated Japan within global history, although they have usually been accompanied by presumptions about the West’s importance for Japan, while at the same time removing Japan from its Asian context. Resituating Japan in its Asian context from a transcultural perspective yields unexpected insights. One example is the role of Islam in Japan, a topic that, although almost entirely unexplored, is closely bound to modern Japanese political history.

In this article we provide a discussion of the definition of palatalization as a ­phonological ­phenomenon, its crosslinguistic variation, phonetic or functional grounding and phonetic (un)naturalness of palatalization, and theoretical approaches to palatalization patterns. After ­providing this background to the collection of articles in this special issue of Glossa we will give an overview of the contributions collected here.

Introduction to the special issue

This work's aim was to minimize the acquisition time of a radial 3D ultra-short echo-time (UTE) sequence and to provide fully automated, gradient delay compensated, and therefore artifact free, reconstruction. The radial 3D UTE sequence (echo time 60 μs) was implemented as single echo acquisition with center-out readouts and improved time efficient spoiling on a clinical 3T scanner without hardware modifications. To assess the sequence parameter dependent gradient delays each acquisition contained a quick calibration scan and utilized the phase of the readouts to detect the actual k-space center. This calibration scan does not require any user interaction. To evaluate the robustness of this automatic delay estimation phantom experiments were performed and 19 in vivo imaging data of the head, tibial cortical bone, feet and lung were acquired from 6 volunteers. As clinical application of this fast 3D UTE acquisition single breath-hold lung imaging is demonstrated. The proposed sequence allowed very short repetition times (TR~1ms), thus reducing total acquisition time. The proposed, fully automated k-phase based gradient delay calibration resulted in accurate delay estimations (difference to manually determined optimal delay -0.13 ± 0.45 μs) and allowed unsupervised reconstruction of high quality images for both phantom and in vivo data. The employed fast spoiling scheme efficiently suppressed artifacts caused by incorrectly refocused echoes. The sequence proved to be quite insensitive to motion, flow and susceptibility artifacts and provides oversampling protection against aliasing foldovers in all directions. Due to the short TR, acquisition times are attractive for a wide range of clinical applications. For short T2* mapping this sequence provides free choice of the second TE, usually within less scan time as a comparable dual echo UTE sequence.

This special double issue (41.1 and 41.2) contains 11 articles on the formal properties of linguistic feature systems, all of which were presented at a conference in Tromsø in the fall of 2013. The issue was jointly edited by Martin Krämer, Sandra Ronai, and Peter Svenonius. A version of the original call for papers posted in 2013 follows. All formal models of linguistics assume sets of features in terms of which generalizations can be stated. But the nature of the features themselves is often not explicitly addressed. In this special double issue of Nordlyd we focus on the nature of features across phonology and syntax and related domains of linguistics. One group of questions concerns the ‘grounding’ of features in substance or content. For example, phonological features may be grounded in phonetics, and syntactic features may be grounded in semantics. Innatist traditions have sometimes posited innate universal inventories of grounded features. The ‘substance-free’ movement in phonology argues instead that the formal properties of features can and should be radically dissociated from their grounding in content. Sign language phonology would seem to support this position, as the featural system of sign language phonology operates with a completely different set of articulators from those used in spoken languages. Minimalist syntax also frequently promotes the dissociation of formal properties of features from their content (as in the proposal that tense is simply one of a variety of ways in which Infl may be ‘grounded,’ favored in Indo-European languages but with various other languages opting for other content for Infl). Such proposals raise many questions concerning how feature systems are constrained to be uniform across languages and to what extent they are free to vary. The radically opposing view in phonology denies the existence of categorical features altogether and attempts to model phonological patterns as statistical computation of phonetic data. The formal structure of features raises another set of questions. Complex patterns of feature locality gave rise to feature geometries in phonology, and these have been developed further to account for dependencies among features, not only in phonology but also in syntax. Cartographic work typically assumes linear hierarchies. To what extent are the various geometries and hierarchies motivated, and how might they be grounded in a broader explanatory theory? Interacting with these questions about the “geometric” relations among features is the algebraic structure of the features. For example, it is often assumed that privativity, in which opposition is marked by presence versus absence, is conceptually simplest and therefore the zero hypothesis. While in phonology the pendulum currently swings towards privativity, recently arguments have come from morphosyntax that features have binary values. While apparent ternary patterns in phonology have been taken as arguments in favor of binarity, such patterns have more recently been accounted for by reference to class nodes. Theories such as HPSG or Government Phonology assume much more complex relations among features (with HPSG even allowing feature-value matrices in which the values are feature-value matrices, extending to a kind of feature recursion, and GP positing government and licensing relations between features and positions). In this volume, a selection of researchers address these and other questions about the nature of features in linguistic theory.

The syllabification of word- or morpheme-internal consonants, especially those preceded by short vowels, in Germanic languages has been subject to various analyses and there is generally not much consensus on the analysis of single string-internal consonants in these languages. This paper presents the results of a study based on a word game, carried out with German and Norwegian subjects, that provides evidence for a differential analysis of string-internal syllable junctures and consonants in these two languages. We conclude that in German a consonant preceded by a short/lax stressed vowel is best analysed as short and ambisyllabic while in Norwegian a consonant in the same environment is a geminate that contributes weight to the preceding syllable via its mora even though it is parsed in the following syllable. The analysis highlights the need for orthogonal syllable and moraic representations.