bluuebunny/crossref_metadata_2025 huggingface dataset:
Innovation Without Entrepreneurship: The Pipe Dream of Mission-Oriented Innovation Policy
Authors: Larsson Johan P.
Published: April 2022

In this chapter, I analyze state entrepreneurship, as exercised through mission-oriented innovation policy: the mobilization of large pools of resources and capabilities to solve the pressing issues of our time. The state entrepreneur is not subject to real risk, often faces no market, and cannot be properly evaluated. It pays no price for being wrong and it struggles in assigning responsibility. Missions are motivated by a false dichotomy: that there is a difference in principle between fixing and creating markets. This premise is splitting hairs at best. Instead, what sets missions apart, other than sheer ambition, is a shift from bottom-up to top-down approaches to knowledge creation. Missions are most likely to achieve intended ends when reasonable people agree on the problem, what needs to be done, and when responsibility can be assigned. Even then, opportunity costs are ignored. The entrepreneurial state is currently pushing to solve those issues where it is likely to do the least good and the most harm: where we lack the knowledge of what to do, where accountability is unassigned, and where the failure-success axis cannot be meaningfully assessed. Successful missionpolicyfurther requirespoliticswell beyond what democratic systems can achieve.
Building Local Innovation Support Systems: Theory and Practice
Authors: Hjalmarsson Dan
Published: April 2022

Interest in innovation as a way of meeting societal challenges is increasing. Interest in different types of public innovation support is therefore increasing as well. Umeå University has many years of experience in developing and operating a well-functioning innovation support system. A common theme is to offer project owners creative arenas as context for entrepreneurial judgments and assessments during the various steps of the innovation process. Improved program theories are needed to enable evaluations that provide feedback, learning, and accountability.
Reducing Higher Education Bureaucracy and Reclaiming the Entrepreneurial University
Authors: Terjesen Siri
Published: April 2022

This chapter documents the worrying trend of increased levels of top-down policies that stifle universities’ innovativeness and autonomy. I highlight the bureaucratization of corporations and higher education institutions, and how this sclerosis results in a widespread sapping of individual initiative and innovation. The chapter next reviews regulation and bureaucratization in higher education with a special focus on commonalities and differences at two levels: university-wide and one sub-unit, the college of business. I describe successful case studies in anti-bureaucracy policies and practices across higher education at the individual, business unit, university, and other levels to highlight cross-level best practices in higher education, including calculating the present bureaucratic mass and administrative burdens of proposed changes, implementing technology solutions, leading change management efforts across all levels, and employing best practices in decision-making. I conclude with a discussion of research directions that will lead to theoretical, methodological, and phenomenological contributions.
Evaluating Evaluations of Innovation Policy: Exploring Reliability, Methods, and Conflicts of Interest
Authors: Collin Elias , Sandström Christian , Wennberg Karl
Published: April 2022

Expansions of innovation policies have been paralleled with an increase in the evaluations of such policies. Yet, there are few systematic evaluations of how such evaluations are conducted, by whom, and their overall conclusions. We analyze 110 evaluations of innovation policy in Sweden from 2005 to 2019. Our findings show that the majority of these evaluations are positive, about one-third are neutral in their conclusions, and very few are negative. The majority of evaluations were conducted by consulting firms, close to one-third by expert government agencies, and around 10% by university researchers or as self-evaluations by the governmental agencies responsible for the policy themselves. Few evaluations employed causal methods to assess the potential effects of policies. We discuss conflicts of interest and question the reliability of evaluations of innovation policy.
Pacman geometries and the Hayward term in JT gravity
Authors: Arias Raúl , Botta-Cantcheff Marcelo , Martinez Pedro J.
Published: April 2022

Abstract

We study the Hayward term describing corners in the boundary of the geometry in the context of the Jackiw-Teitelboim gravity. These corners naturally arise in the computation of Hartle-Hawking wave functionals and reduced density matrices, and give origin to AdS spacetimes with conical defects.

This set up constitutes a lab to manifestly realize many aspects of the construction recently proposed in [1]. In particular, it can be shown that the Hayward term is required to reproduce the flat spectrum of Rényi entropies in the Fursaev’s derivation, and furthermore, the action with an extra Nambu-Goto term associated to the Dong’s cosmic brane prescription appears naturally.

On the other hand, the conical defect coming from Hayward term contribution are subtly different from the defects set as pointlike sources studied previously in the literature. We study and analyze these quantitative differences in the path integral and compare the results. Also study previous proposals on the superselection sectors, and by computing the density operator we obtain the Shannon entropy and some novel results on the symmetry group representations and edge modes. It also makes contact with the so-called defect operator found in [2].

Lastly, we obtain the area operator as part of the gravitational modular Hamiltonian, in agreement with the Jafferis-Lewkowycz-Maldacena-Suh proposal.
Delayed deconfinement and the Hawking-Page transition
Authors: Copetti Christian , Grassi Alba , Komargodski Zohar , Tizzano Luigi
Published: April 2022

Abstract

We revisit the confinement/deconfinement transition in $$ \mathcal{N} $$
N
= 4 super Yang-Mills (SYM) theory and its relation to the Hawking-Page transition in gravity. Recently there has been substantial progress on counting the microstates of 1/16-BPS extremal black holes. However, there is presently a mismatch between the Hawking-Page transition and its avatar in $$ \mathcal{N} $$
N
= 4 SYM. This led to speculations about the existence of new gravitational saddles that would resolve the mismatch. Here we exhibit a phenomenon in complex matrix models which we call “delayed deconfinement.” It turns out that when the action is complex, due to destructive interference, tachyonic modes do not necessarily condense. We demonstrate this phenomenon in ordinary integrals, a simple unitary matrix model, and finally in the context of $$ \mathcal{N} $$
N
= 4 SYM. Delayed deconfinement implies a first-order transition, in contrast to the more familiar cases of higher-order transitions in unitary matrix models. We determine the deconfinement line and find remarkable agreement with the prediction of gravity. On the way, we derive some results about the Gross-Witten-Wadia model with complex couplings. Our techniques apply to a wide variety of (SUSY and non-SUSY) gauge theories though in this paper we only discuss the case of $$ \mathcal{N} $$
N
= 4 SYM.
Photon-photon scattering from a UV-complete gravity QFT
Authors: Holdom Bob
Published: April 2022

Abstract

Quantum quadratic gravity (QQG) produces a tree-level differential cross section for γγγγ that is well-behaved at all energies. From this we can study how the corrections to low energy scattering amplitudes are related to the UV physics, in particular to the exchange of the massive graviparticles. An effective forward scattering amplitude is obtained by separating out the effects of the t-channel graviton pole. This is possible due to the UV-completeness, and even though the Froissart bound is not satisfied. We then consider photon-photon scattering to two graviparticles and a further imaginary contribution to the γγγγ forward scattering amplitude. Unitarity without positivity is a key property of QQG and it impacts all our results.
Kasner geometries inside holographic superconductors
Authors: Sword Lewis , Vegh David
Published: April 2022

Abstract

The recent study of holographic superconductors has shown the emergence of a Kasner universe behind the event horizon. This paper serves to add to the discussion by introducing two modifications to the holographic superconductor model: an axion field term and an Einstein-Maxwell-scalar (EMS) coupling term. We first discuss the effect the modification parameters have on the condensate then explore the black hole interior dynamics. Features previously identified in the interior are found in the model presented, including the collapse of the Einstein-Rosen bridge, Josephson oscillations and Kasner inversions/transitions. However, we find that by increasing the EMS coupling parameter, the collapse does not occur near the axion-Reissner-Nordström horizon and the oscillations are no longer present; the geometry entering into a Kasner regime after a large-rcollapse instead.
$$ T\overline{T} $$ deformations and the width of fundamental particles
Authors: Cardy John , Doyon Benjamin
Published: April 2022

Abstract

We provide a simple geometric meaning for deformations of so-called $$ T\overline{T} $$
T

T
¯

type in relativistic and non-relativistic systems. Deformations by the cross products of energy and momentum currents in integrable quantum field theories are known to modify the thermodynamic Bethe ansatz equations by a “CDD factor”. In turn, CDD factors may be interpreted as additional, fixed shifts incurred in scattering processes: a finite width added to the fundamental particles (or, if negative, to the free space between them). We suggest that this physical effect is a universal way of understanding $$ T\overline{T} $$
T

T
¯

deformations, both in classical and quantum systems. We first show this in non-relativistic systems, with particle conservation and translation invariance, using the deformation formed out of the densities and currents of particles and momentum. This holds at the level of the equations of motion, and for any interaction potential, integrable or not. We then argue, and show by similar techniques in free relativistic particle systems, that $$ T\overline{T} $$
T

T
¯

deformations of relativistic systems produce the equivalent phenomenon, accounting for length contractions. We also show that, in both the relativistic and non-relativistic cases, the width of particles is equivalent to a state-dependent change of metric, where the distance function discounts the particles’ widths, or counts the additional free space. This generalises and explains the known field-dependent coordinate change describing $$ T\overline{T} $$
T

T
¯

deformations. The results connect such deformations with generalised hydrodynamics, where the relations between scattering shifts, widths of particles and state-dependent changes of metric have been established.
Improved constraints on effective top quark interactions using edge convolution networks
Authors: Atkinson Oliver , Bhardwaj Akanksha , Brown Stephen , Englert Christoph , Miller David J. , Stylianou Panagiotis
Published: April 2022

Abstract

We explore the potential of Graph Neural Networks (GNNs) to improve the performance of high-dimensional effective field theory parameter fits to collider data beyond traditional rectangular cut-based differential distribution analyses. In this study, we focus on a SMEFT analysis of pp → $$ t\overline{t} $$
t

t
¯

production, including top decays, where the linear effective field deformation is parametrised by thirteen independent Wilson coefficients. The application of GNNs allows us to condense the multidimensional phase space information available for the discrimination of BSM effects from the SM expectation by considering all available final state correlations directly. The number of contributing new physics couplings very quickly leads to statistical limitations when the GNN output is directly employed as an EFT discrimination tool. However, a selection based on minimising the SM contribution enhances the fit’s sensitivity when reflected as a (non-rectangular) selection on the inclusive data samples that are typically employed when looking for non-resonant deviations from the SM by means of differential distributions.
Free-lattice functors weakly preserve epi-pullbacks
Authors: Gumm H. Peter , Freese Ralph S.
Published: April 2022

Supposep(x, y, z) andq(x, y, z) are terms. If there is a common “ancestor” term$$s(z_{1},z_{2},z_{3},z_{4})$$s(z1,z2,z3,z4)specializing topandqthrough identifying some variables$$\begin{aligned} p(x,y,z)&\approx s(x,y,z,z)\\ q(x,y,z)&\approx s(x,x,y,z), \end{aligned}$$p(x,y,z)≈s(x,y,z,z)q(x,y,z)≈s(x,x,y,z),then the equation$$\begin{aligned} p(x,x,z)\approx q(x,z,z) \end{aligned}$$p(x,x,z)≈q(x,z,z)is a trivial consequence. In this note we show that for lattice terms, and more generally for terms of lattice-ordered algebras, a converse is true, too. Given termsp, q,  and an equation where$$\{u_{1},\ldots ,u_{m}\}=\{v_{1},\ldots ,v_{n}\},$${u1,…,um}={v1,…,vn},there is always an “ancestor term”$$s(z_{1},\ldots ,z_{r})$$s(z1,…,zr)such that$$p(x_{1},\ldots ,x_{m})$$p(x1,…,xm)and$$q(y_{1},\ldots ,y_{n})$$q(y1,…,yn)arise as substitution instances ofs,  whose unification results in the original equation ($$*$$∗). In category theoretic terms the above proposition, when restricted to lattices, has a much more concise formulation:Free-lattice functors weakly preserve pullbacksof epis. Finally, we show thatweakpreservation is all that we can hope for. We prove that for an arbitrary idempotent variety$${{\mathcal {V}}}$$Vthe free-algebra functor$$F_{{\mathcal {V}}}$$FVwill notpreservepullbacks of epis unless$${{\mathcal {V}}}$$Vis trivial (satisfying$$x\approx y$$x≈y) or$${{\mathcal {V}}}$$Vcontains the “variety of sets” (where all operations are implemented as projections).
On Multimatrix Models Motivated by Random Noncommutative Geometry II: A Yang-Mills-Higgs Matrix Model
Authors: Perez-Sanchez Carlos I.
Published: April 2022

We continue the study of fuzzy geometries inside Connes’ spectral formalism and their relation to multimatrix models. In this companion paper to Pérez-Sánchez (Ann Henri Poincaré 22:3095–3148, 2021, arXiv:2007.10914), we propose a gauge theory setting based on noncommutative geometry, which—just as the traditional formulation in terms of almost-commutative manifolds—has the ability to also accommodate a Higgs field. However, in contrast to ‘almost-commutative manifolds’, the present framework, which we call gauge matrix spectral triples, employs only finite-dimensional algebras. In a path-integral quantization approach to the Spectral Action, this allows to state Yang–Mills–Higgs theory (on four-dimensional Euclidean fuzzy space) as an explicit random multimatrix model obtained here, whose matrix fields exactly mirror those of the Yang–Mills–Higgs theory on a smooth manifold.
Implications of Underground Nuclear Explosion Cavity Evolution for Radioxenon Isotopic Composition
Authors: Sun Yunwei , Carrigan Charles R. , Pili Eric , Antoun Tarabay
Published: April 2022

Isotopic ratios of radioxenons sampled in the atmosphere or subsurface can be used to verify the occurrence of an underground nuclear explosion (UNE). Differences in the half-lives of radioactive xenon precursors and their decay-chain networks produce different time-dependent concentration profiles of xenon isotopes allowing isotopic ratios to be used for tracking UNE histories including estimating the time of detonation. In this study, we explore the potential effects of post-detonation cavity processes: precipitation of iodine precursors, gas seepage, and prompt venting on radioxenon isotopic evolution which influences UNE histories. Simplified analytical models and closed-form solutions yielding a potentially idealized radioactive decay/ingrowth chain in a closed and well-mixed system typically have limited application by not including the partitioning of the radionuclide inventory between a gas phase and rock melt created by the detonation and by ignoring gas transport from the cavity to host rock or ground surface. In reality, either subsurface transport or prompt release that is principally responsible for gas signatures violates the closed-system (or batch-mode) assumption. A closed-form solution representing time-dependent source-term activities is extended by considering the cavity partitioning process, slow seepage, and/or prompt release of gases from the cavity and applied to realistic systems.
Symbiont demand guides resource supply: leaf-cutting ants preferentially deliver their harvested fragments to undernourished fungus gardens
Authors: Römer Daniela , Aguilar Gonzalo Pacheco , Meyer Annika , Roces Flavio
Published: April 2022

Leaf-cutting ants are highly successful herbivores in the Neotropics. They forage large amounts of fresh plant material to nourish a symbiotic fungus that sustains the colony. It is unknown how workers organize the intra-nest distribution of resources, and whether they respond to increasing demands in some fungus gardens by adjusting the amount of delivered resources accordingly. In laboratory experiments, we analyzed the spatial distribution of collected leaf fragments among nest chambers in Acromyrmex ambiguus leaf-cutting ants, and how it changed when one of the fungus gardens experienced undernourishment. Plant fragments were evenly distributed among nest chambers when the fungal symbiont was well nourished. That pattern changed when one of the fungus gardens was undernourished and had a higher leaf demand, resulting in more leaf discs delivered to the undernourished fungus garden over at least 2 days after deprivation. Some ants bypassed nourished gardens to directly deliver their resource to the chamber with higher nutritional demand. We hypothesize that cues arising from that chamber might be used for orientation and/or that informed individuals, presumably stemming from the undernourished chamber, may preferentially orient to them.
Resolvent-based approach for $$\pmb {H_2}$$-optimal estimation and control: an application to the cylinder flow
Authors: Jin Bo , Illingworth Simon J. , Sandberg Richard D.
Published: April 2022

We consider estimation and control of the cylinder wake at low Reynolds numbers. A particular focus is on the development of efficient numerical algorithms to design optimal linear feedback controllers when there are many inputs (disturbances applied everywhere) and many outputs (perturbations measured everywhere). We propose a resolvent-based iterative algorithm to perform (i) optimal estimation of the flow using a limited number of sensors, and (ii) optimal control of the flow when the entire flow is known but only a limited number of actuators are available for control. The method takes advantage of the low-rank characteristics of the cylinder wake and provides full-dimensional solutions by implementing a terminal reduction technique based on resolvent analysis. Optimal feedback controllers are also obtained by combining the solutions of the estimation and control problems. We show that the performance of the estimators and controllers converges to the true global optima, indicating that the important physical mechanisms for estimation and control are of low rank.

Graphic abstract
Pancreatic shear wave elastography in children with type 1 diabetes: relation to diabetes duration, glycemic indices, fasting C-peptide and diabetic complications
Authors: Salah Nouran Yousef , Madkour Sherihane Said , Soliman Khaled Sayed
Published: April 2022

Background

Little is known about changes in the pancreas as the course of type 1 diabetes progresses. Recently, shear wave elastography (SWE) emerged as a tool for assessing pancreatic stiffness in chronic pancreatitis and pancreatic cancer with a few studies assessing it in diabetes.

Objective

To compare pancreatic SWE in children with recent-onset and long-standing type 1 diabetes to healthy controls and to correlate it with diabetes duration, glycated hemoglobin (HbA1C), functional B cell reserve (fasting C-peptide) and diabetic complications.

Materials and methods

Fifty children with type 1 diabetes (25 with recent-onset and 25 with long-standing type 1 diabetes) and 50 controls were enrolled. Diabetes duration, insulin therapy, fundoscopic examination of the eyes and the neuropathy disability score were assessed. Fasting C-peptide, lipids, HbA1C and urinary albumin-creatinine ratio were measured. Pancreatic SWE was measured using the General Electric Logiq P9 ultrasound system.

Results

The mean SWE of the studied children with recent-onset type 1 diabetes was 4.81±0.62 kilopascals (Kpa), those with long-standing type 1 diabetes was 7.10±1.56Kpa and for controls was 5.57±0.27 Kpa (P<0.001). SWE was positively correlated to diabetes duration (P<0.001) and negatively correlated to fasting C-peptide (P<0.001). Regarding diabetes complications, SWE was positively correlated to frequency of severe hypoglycemia (P=0.005), HbA1C (P=0.03), low-density lipoproteins (P<0.001) and cholesterol (P<0.001) and significantly related to diabetic neuropathy (P=0.04) and nephropathy (P=0.05). Diabetes duration, fasting C-peptide, HbA1C and frequency of severe hypoglycemia were the significant independent variables related to SWE increase by multivariable regression analysis.

Conclusion

Pancreatic SWE changes significantly with duration of type 1 diabetes, being lowest in those with recent-onset type 1 diabetes and highest in those with long-standing type 1 diabetes, particularly those with diabetic nephropathy and neuropathy.
When Older Males Sire More Offspring—Increased Attractiveness or Higher Fertility?
Authors: Lifjeld Jan T. , Kleven Oddmund , Fossøy Frode , Jacobsen Frode , Laskemoen Terje , Rudolfsen Geir , Robertson Raleigh J.
Published: April 2022

In birds with extrapair mating, older males usually have higher fertilization success than younger males. Two hypotheses can potentially explain this pattern: 1) females prefer older, and often more ornamented males, or 2) older males invest more in reproduction and fertility than younger males. Here we studied factors associated with age-related male fertilization success in a population of barn swallowsHirundo rusticain Canada. We document that male fertilization success increased gradually up to a minimum age of four-year old. The age effect was especially strong for the number of extrapair offspring obtained and the occurrence of a second brood. The higher fertilization success of older males was also associated with an early start of breeding in spring. The length of the elongated outermost tail feathers, a postulated male ornament preferred by females, also increased with age (in both sexes), but it was not a significant predictor of male fertilization success within age classes. Male fertility traits, especially testis size, but also sperm motility and sperm velocity, increased significantly across age groups. Our results suggest that the higher fertilization success by older males is due to their higher reproductive investments and that their longer tails are an adaptation to early arrival on the breeding grounds.

Significance statement

The barn swallow is a socially monogamous passerine with extensive extrapair mating. We found that males become more successful in siring both withinpair and extrapair offspring as they become older. Their increased fertilization success was associated with a higher reproductive effort as indicated by larger testes, more motile sperm, and an earlier start of breeding in spring. The length of the outer tail feathers increased with age in both sexes, but long tails did not enhance male fertilization success among males of the same age. Long tails are probably an adaptation to rapid migration and earlier arrival on the breeding grounds. Our findings suggest that the commonly observed age-related increase in male fertilization success in passerine birds is better explained by life history theory than by sexual selection theory.
Effects of late, repetitive remote ischaemic conditioning on myocardial strain in patients with acute myocardial infarction
Authors: Arnold J. Ranjit , P.Vanezis Andrew , Rodrigo Glenn C. , Lai Florence Y. , Kanagala Prathap , Nazir Sheraz , Khan Jamal N. , Ng Leong , Chitkara Kamal , Coghlan J. Gerry , Hetherington Simon , Samani Nilesh J. , McCann Gerald P.
Published: April 2022

Late, repetitive or chronic remote ischaemic conditioning (CRIC) is a potential cardioprotective strategy against adverse remodelling following ST-segment elevation myocardial infarction (STEMI). In the randomised Daily Remote Ischaemic Conditioning Following Acute Myocardial Infarction (DREAM) trial, CRIC following primary percutaneous coronary intervention (P-PCI) did not improve global left ventricular (LV) systolic function. A post-hoc analysis was performed to determine whether CRIC improved regional strain. All 73 patients completing the original trial were studied (38 receiving 4 weeks’ daily CRIC, 35 controls receiving sham conditioning). Patients underwent cardiovascular magnetic resonance at baseline (5–7 days post-STEMI) and after 4 months, with assessment of LV systolic function, infarct size and strain (longitudinal/circumferential, in infarct-related and remote territories). At both timepoints, there were no significant between-group differences in global indices (LV ejection fraction, infarct size, longitudinal/circumferential strain). However, regional analysis revealed a significant improvement in longitudinal strain in the infarcted segments of the CRIC group (from − 16.2 ± 5.2 at baseline to − 18.7 ± 6.3 at follow up, p = 0.0006) but not in corresponding segments of the control group (from − 15.5 ± 4.0 to − 15.2 ± 4.7, p = 0.81; for change: − 2.5 ± 3.6 versus + 0.3 ± 5.6, respectively, p = 0.027). In remote territories, there was a lower increment in subendocardial circumferential strain in the CRIC group than in controls (− 1.2 ± 4.4 versus − 2.5 ± 4.0, p = 0.038). In summary, CRIC following P-PCI for STEMI is associated with improved longitudinal strain in infarct-related segments, and an attenuated increase in circumferential strain in remote segments. Further work is needed to establish whether these changes may translate into a reduced incidence of adverse remodelling and clinical events. Clinical Trial Registration: http://clinicaltrials.gov/show/NCT01664611.
Indications for surgical fixation of low-energy pelvic ring fractures in elderly: a systematic review
Authors: Timmer R. A. , Verhage S. M. , Krijnen P. , Meylaerts S. A. G. , Schipper I. B.
Published: April 2022

Introduction

There are no generally accepted criteria for when and how to fixate osteoporotic pelvic ring fractures in elderly. This systemic review aims to summarize the currently available literature regarding the indications and methods for surgical fixation of fragility fractures of the pelvic ring in elderly patients after low-energy trauma.

Materials and methods

The Pubmed and Embase databases were searched using the key words pelvic fractures, geriatric, fragility, osteoporosis, and surgical fixation, and their synonyms. Extracted data including the indication, method of operative fixation, and post-operative outcomes (pain levels, mobility, complications and mortality) were analyzed using descriptive statistics. The studies were too heterogeneous to perform a meta-analysis.

Results

Eleven cohort studies (3 comparative and 8 noncomparative) were included. The methodological quality was poor to moderate; the studies were heterogeneous regarding study design and reported outcomes. In all included studies operative treatment for all fracture types was preceded by a period of conservative treatment comprising physiotherapy-guided full weight-bearing. Time to surgery differed widely. For posterior ring fixation, the majority of the included studies used minimally invasive surgery with trans-iliosacral screws. Five studies described a form of additional fixation of the anterior pelvic ring but did not report the indications.

Conclusions

Fixation of low-energy pelvic ring fractures in elderly is commonly performed after a period of conservative treatment, with persistent pain as the most frequent indication for fixation. Fracture classification based on stability seems to be of secondary importance. Timing for surgical fixation of the pelvic ring fracture in elderly patients remains diverse. Large well-designed comparative prospective studies and randomized controlled trials are needed to provide clearly substantiated guidelines.
Cortico-amygdalar connectivity and externalizing/internalizing behavior in children with neurodevelopmental disorders
Authors: Nakua Hajer , Hawco Colin , Forde Natalie J. , Jacobs Grace R. , Joseph Michael , Voineskos Aristotle N. , Wheeler Anne L. , Lai Meng-Chuan , Szatmari Peter , Kelley Elizabeth , Liu Xudong , Georgiades Stelios , Nicolson Rob , Schachar Russell , Crosbie Jennifer , Anagnostou Evdokia , Lerch Jason P. , Arnold Paul D. , Ameis Stephanie H.
Published: April 2022

Background

Externalizing and internalizing behaviors contribute to clinical impairment in children with neurodevelopmental disorders (NDDs). Although associations between externalizing or internalizing behaviors and cortico-amygdalar connectivity have been found in clinical and non-clinical pediatric samples, no previous study has examined whether similar shared associations are present across children with different NDDs.

Methods

Multi-modal neuroimaging and behavioral data from the Province of Ontario Neurodevelopmental Disorders (POND) Network were used. POND participants aged 6–18 years with a primary diagnosis of autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD) or obsessive–compulsive disorder (OCD), as well as typically developing children (TDC) with T1-weighted, resting-state fMRI or diffusion weighted imaging (DWI) and parent-report Child Behavioral Checklist (CBCL) data available, were analyzed (total n = 346). Associations between externalizing or internalizing behavior and cortico-amygdalar structural and functional connectivity indices were examined using linear regressions, controlling for age, gender, and image-modality specific covariates. Behavior-by-diagnosis interaction effects were also examined.

Results

No significant linear associations (or diagnosis-by-behavior interaction effects) were found between CBCL-measured externalizing or internalizing behaviors and any of the connectivity indices examined. Post-hoc bootstrapping analyses indicated stability and reliability of these null results.

Conclusions

The current study provides evidence towards an absence of a shared linear relationship between internalizing or externalizing behaviors and cortico-amygdalar connectivity properties across a transdiagnostic sample of children with different primary NDD diagnoses and TDC. Different methodological approaches, including incorporation of multi-dimensional behavioral data (e.g., task-based fMRI) or clustering approaches may be needed to clarify complex brain-behavior relationships relevant to externalizing/internalizing behaviors in heterogeneous clinical NDD populations.
The role of the default mode network in longitudinal functional brain reorganization of brain gliomas
Authors: Saviola Francesca , Zigiotto Luca , Novello Lisa , Zacà Domenico , Annicchiarico Luciano , Corsini Francesco , Rozzanigo Umberto , Papagno Costanza , Jovicich Jorge , Sarubbo Silvio
Published: April 2022

The study of patients after glioma resection offers a unique opportunity to investigate brain reorganization. It is currently unknown how the whole-brain connectomic profile evolves longitudinally after surgical resection of a glioma and how this may be associated with tumor characteristics and cognitive outcome. In this longitudinal study, we investigate the impact of tumor lateralization and grade on functional connectivity (FC) in highly connected networks, or hubs, and cognitive performance. Twenty-eight patients (17 high-grade, 11 low-grade gliomas) underwent longitudinal pre/post-surgery resting-state fMRI scans and neuropsychological assessments (73 total measures). FC matrices were constructed considering as functional hubs the default mode (DMN) and fronto-parietal networks. No-hubs included primary sensory functional networks and any other no-hubs nodes. Both tumor hemisphere and grade affected brain reorganization post-resection. In right-hemisphere tumor patients, regardless of grade and relative to left-hemisphere gliomas, FC increased longitudinally after the intervention, both in terms of FC within hubs (phubs = 0.0004) and FC between hubs and no-hubs (phubs-no-hubs = 0.005). Regardless of tumor side, only lower-grade gliomas showed longitudinal FC increases relative to high-grade tumors within a precise hub network, the DMN. The neurocognitive profile was longitudinally associated with spatial features of the connectome, mainly within the DMN. We provide evidence that clinical glioma features, such as lateralization and grade, affect post-surgical longitudinal functional reorganization and cognitive recovery. The data suggest a possible role of the DMN in supporting cognition, providing useful information for prognostic prediction and surgical planning.
A therapeutic guide on pediatric irritable bowel syndrome and functional abdominal pain-not otherwise specified
Authors: Rexwinkel Robyn , Vlieger Arine M. , Saps Miguel , Tabbers Merit M. , Benninga Marc A.
Published: April 2022

Disorders of the gut-brain interaction negatively impact quality of life and carry a substantial socioeconomic burden. Irritable bowel syndrome (IBS) and functional abdominal pain-not otherwise specified (FAP-NOS) are common functional abdominal pain disorders in childhood. The pathophysiology is not fully understood, and high-quality intervention trials and international guidelines are missing. Therefore, the management of these disorders remains challenging. This review aims to provide an up-to-date overview of therapeutic possibilities for pediatric IBS or FAP-NOS and recommends management strategies. To prevent unnecessary referrals and extensive costs, it is fundamental to make a positive diagnosis of IBS or FAP-NOS in children with chronic abdominal pain with only minimal investigations. A tailor-made approach for each patient, based on the accompanying physical and psychological symptoms, is proposed to date.

Conclusion: Shared decision-making including non-pharmacological and pharmacological interventions should be considered and discussed with the family.What is Known:• Irritable bowel syndrome and functional abdominal pain-not otherwise specified are common in childhood.• Although the number of treatment options has grown recently, managing these disorders can be challenging and unsatisfactory, and no evidence-based international management guidelines are available.What is New:• We suggest using a stepwise individualized approach to management, where after first-line management, both non-pharmacological and pharmacological interventions should be discussed.
A hyperelastic extended Kirchhoff–Love shell model with out-of-plane normal stress: I. Out-of-plane deformation
Authors: Taniguchi Yasutoshi , Takizawa Kenji , Otoguro Yuto , Tezduyar Tayfun E.
Published: April 2022

This is the first part of a two-part article on a hyperelastic extended Kirchhoff–Love shell model with out-of-plane normal stress. We present the derivation of the new model, with focus on the mechanics of the out-of-plane deformation. Accounting for the out-of-plane normal stress distribution in the out-of-plane direction affects the accuracy in calculating the deformed-configuration out-of-plane position, and consequently the nonlinear response of the shell. The improvement is beyond what we get from accounting for the out-of-plane deformation mapping. By accounting for the out-of-plane normal stress, the traction acting on the shell can be specified on the upper and lower surfaces separately. With that, the new model is free from the “midsurface” location in terms of specifying the traction. We also present derivations related to the variation of the kinetic energy and the form of specifying the traction and moment acting on the upper and lower surfaces and along the edges. We present test computations for unidirectional plate bending, plate saddle deformation, and pressurized cylindrical and spherical shells. We use the neo-Hookean and Fung’s material models, for the compressible- and incompressible-material cases, and with the out-of-plane normal stress and without, which is the plane-stress case.
Missing trial results: analysis of the current publication rate of studies in pediatric dialysis from 2003 to 2020
Authors: Patry Christian , Fichtner Alexander , Höcker Britta , Ries Markus , Schmitt Claus Peter , Tönshoff Burkhard
Published: April 2022

Background

Decision-making in the field of pediatric dialysis requires evidence from clinical trials, but, similar to other fields of pediatric medicine, might be affected by a low trial publication rate.

Methods

We analyzed the current publication rate, the time to publication, and factors that might be associated with both rate of and time to publication in pediatric dialysis studies registered as completed on ClinicalTrials.gov from 2003 until November 2020.

Results

Fifty-three respective studies were identified. These enrolled 7287 patients in total. 28 of 53 studies (52.8%) had results available. We identified a median time to publication of 20.5 months (range, 3–67). Studies published after the FDA Amendments Act establishment in 2007 were published faster (P = 0.025). There was no trend toward a higher publication rate of studies completed more recently (P = 0.431). 26 of 53 studies (49.1%) focused on medication and control of secondary complications of kidney failure. 12 of 53 studies (22.6%) enrolled only children, were published faster (P = 0.029) and had a higher 5-year publication rate (P = 0.038) than studies enrolling both children and adults. 25 of 53 studies (47.1%) were co-funded by industry. These were published faster (P = 0.025).

Conclusions

Currently, only 52.8% of all investigated studies in pediatric dialysis have available results, and the overall median time to publication did not meet FDA requirements. This might introduce a publication bias into the field, and it might negatively impact clinical decision-making in this critical subspecialty of pediatric medicine.

Graphical abstract

A higher resolution version of the Graphical abstract is available as Supplementary information
On the effectiveness of a rod-like distributed piezoelectric controller in preventing the Hopf bifurcation of the visco-elastic Beck’s beam
Authors: Casalotti Arnaldo , D’Annibale Francesco
Published: April 2022

The linear stability of a piezo-electro-mechanical (PEM) system subject to a follower force is here discussed. The mechanical subsystem is constituted by a linear visco-elastic cantilever beam, loaded by a follower force at the free end. It suffers from the Hopf bifurcation, whose critical load is strongly affected by damping, according to the well-known Ziegler’s paradox. On the other hand, the electrical subsystem consists of a distributed array of piezoelectric patches attached to the beam and connected to a properly designed second-order analog circuit, aiming at possibly enhancing the stability of the PEM system. The partial differential equations of motion of the PEM system are discretized by the Galerkin method. Linear stability analysis is then carried out by numerically solving the associated eigenvalue problem, for different significant values of the electrical parameters. A suitable perturbation method is also adopted to detect the role of the electrical parameters and discuss the effectiveness of the controller.
The effects of touchless interaction on usability and sense of presence in a virtual environment
Authors: De Paolis Lucio Tommaso , De Luca Valerio
Published: April 2022

For software applications with a significant level of user involvement, the traditional concept of usability has evolved into the more complex idea of user experience, which also covers emotional, cognitive or physical responses. In virtual reality, user experience also depends on the user perception related to some peculiarities of immersive environments, where also the devices employed for user interaction play a determinant role. This has led to the design of the Presence Questionnaire (PQ) for the evaluation of the effectiveness of virtual environments. This work analyzes the effects of two different interaction modalities on usability and sense of presence: in particular, the Myo armband, a gesture-based device for touchless interaction, is compared with the Vive handheld controller bundled with the HTC Vive headset. A total of 84 subjects were recruited to test the virtual environment and asked them to fill in a questionnaire obtained by combining the Usability Metric for User eXperience (UMUX) questionnaire, the System Usability Scale (SUS) and the presence questionnaire (PQ), which was specifically designed for virtual environments. A comparison between the scores obtained for the two interaction modalities revealed which questionnaire items are significantly influenced by the input interface and deduce some insights about the consequences on human factors.
Application value of overlap guiding tube (OGT) in assisting overlap esophagojejunostomy during laparoscopic total gastrectomy for gastric/gastroesophageal junction (G/GEJ) tumors
Authors: Xinhua Chen , Tian Lin , Huilin Huang , Mingli Zhao , Tao Chen , Hao Chen , Jinsheng Mai , Qinglei Zhong , Hao Liu , Liying Zhao , Yanfeng Hu , Guoxin Li , Jiang Yu
Published: April 2022

Background

The overlap guiding tube (OGT) method, which was designed by our team to assist in overlap esophagojejunostomy, could potentially provide new perspectives for esophagojejunostomy. The application of the OGT-assisted method was first explored by our team and has not yet been reported.

Methods

This cohort study analyzed the 3 month outcomes of 38 gastric/gastroesophageal junction (G/GEJ) tumor patients who underwent OGT-assisted overlap esophagojejunostomy.

Results

There were 27 males and 11 females, aged 40–82 years. All patients underwent surgery successfully. The success rate of inserting anvil fork into esophageal lumen at first attempt was 97.4%. The total operation time, esophagojejunostomy time, volume of intraoperative blood loss, and length of surgical incision were 317.6 ± 51.5 min, 20.8 ± 3.8 min, 50.0 (range 15.0–200.0) ml, and 5.0 (range 4.0–8.0) cm, respectively. No procedures were converted to other laparoscopic anastomosis techniques or open approaches. The time to postoperative initial flatus, liquid diet intake, soft diet intake, and length of postoperative hospital stay were 3.0 (range 1.0–6.0) days, 4.0 (range 2.0–9.0)days, 6.0 (range 3.0–11.0) days, and 8.5 (range 6.0–16.0) days, respectively. Overall, postoperative complications were observed in 8 (21.1%) patients. Among them, one patients developed esophagojejunal anastomotic leakage. After 3 months of follow-up, none of the patients developed anastomotic stenosis or experienced unplanned secondary surgery or perioperative death.

Conclusions

OGT-assisted overlap esophagojejunostomy for patients with G/GEJ tumors is safe and feasible, with good short-term effects. OGT method has a satisfactory success rate of inserting anvil fork into esophageal lumen at first attempt and could prevent from developing esophageal submucosa pseudocanals.
Risk factors of recurrence in chronic subdural hematoma and a proposed extended classification of internal architecture as a predictor of recurrence
Authors: Hamou Hussam , Alzaiyani Mohamed , Pjontek Rastislav , Kremer Benedikt , Albanna Walid , Ridwan Hani , Clusmann Hans , Hoellig Anke , Veldeman Michael
Published: April 2022

Chronic subdural hematomas (cSDHs) constitute one of the most prevalent intracranial disease entities requiring surgical treatment. Although mostly taking a benign course, recurrence after treatment is common and associated with additional morbidity and costs. Aim of this study was to develop hematoma-specific characteristics associated with risk of recurrence. All consecutive patients treated for cSDH in a single university hospital between 2015 and 2019 were retrospectively considered for inclusion. Size, volume, and midline shift were noted alongside relevant patient-specific factors. We applied an extended morphological classification system based on internal architecture in CT imaging consisting of eight hematoma subtypes. A logistic regression model was used to assess the classification’s performance on predicting hematoma recurrence. Recurrence was observed in 122 (32.0%) of 381 included patients. Apart from postoperative depressed brain volume (OR 1.005; 95% CI 1.000 to 1.010; p = 0.048), neither demographic nor factors related to patient comorbidity affected recurrence. The extended hematoma classification was identified as a significant predictor of recurrence (OR 1.518; 95% CI 1.275 to 1.808; p < 0.001). The highest recurrence rates were observed in hematomas of the homogenous (isodense: 41.4%; hypodense: 45.0%) and sedimented (50.0%) types. Our results support that internal architecture subtypes might represent stages in the natural history of chronic subdural hematoma. Detection and treatment at a later stage of spontaneous repair can result in a reduced risk of recurrence. Based on their high risk of recurrence, we advocate follow-up after treatment of sedimented and homogenous hematomas.
Gender dimorphism in IgA subclasses in T2-high asthma
Authors: Varricchi Gilda , Poto Remo , Covelli Bianca , Di Spigna Gaetano , Galdiero Maria Rosaria , Marone Gianni , Postiglione Loredana , Spadaro Giuseppe
Published: April 2022

Immunoglobulin A (Chan in J Allergy Clin Immunol 134:1394–14014e4, 2014), the second most abundant immunoglobulin in serum, plays an important role in mucosal homeostasis. In human serum, there are two subclasses of IgA, IgA1 (≅ 90%) and IgA2 (≅ 10%), transcribed from two distinct heavy chain constant regions. This study evaluated the serum concentrations of total IgA, IgA1, and IgA2, and total IgG, IgG1, IgG2, IgG3, and IgG4 in T2-high asthmatics compared to healthy controls and the presence of gender-related variations of immunoglobulins. Total IgA levels were increased in asthmatics compared to controls. Even more marked was the increase in total IgA in male asthmatics compared to healthy male donors. IgA1 were increased only in male, but not in female asthmatics, compared to controls. Concentrations of IgG2, but not IgG1, IgG3, and IgG4, were reduced in asthmatics compared to controls. IgG4 levels were reduced in female compared to male asthmatics. In female asthmatics, IgA and IgA1 levels were increased in postmenopause compared to premenopause. IgA concentrations were augmented in mild, but not severe asthmatics. A positive correlation was found between IgA levels and the age of patients and an inverse correlation between serum concentrations of IgA2 and IgE in asthmatics. A positive correlation between total IgA or IgA2 and IgG2 was found in asthmatics. These results highlight a gender dimorphism in IgA subclasses in male and female T2-high asthmatics. More adequate consideration of immunological gender disparity in asthma may open new opportunities in personalized medicine by optimizing diagnosis and targeted therapy.