bluuebunny/crossref_metadata_2025 huggingface dataset:
Intracranial manifestations of rhinocerebral mucormycosis: a pictorial essay
Authors: Agrawal Alka , Tripathi Prem S. , Shukla Prachi , Nigam Prakhar , Kheti Pramita
Published: April 2022

Rhinocerebral mucormycosis has emerged as a common coinfection in coronavirus disease 2019 (COVID-19) patients during the convalescence period. Frequent spread of disease from sinonasal mucosa to bone, neck spaces, orbit, and brain occurs along the perivascular/perineural routes or through direct invasion. Brain involvement represents severe manifestation and is often associated with poor functional outcomes and high mortality rates. Magnetic resonance imaging (MRI) is the modality of choice for the intracranial assessment of disease severity in mucormycosis. Early and accurate identification of intracranial extension is imperative to improve survival rates. With this pictorial essay, we aim to familiarize the readers with the cross-sectional imaging features of intracranial complications of mucormycosis. The radiological details in this essay should serve as a broad checklist for radiologists and clinicians while dealing with this fulminant infection.
Short-term efficacy and safety of lurasidone versus placebo in antipsychotic-naïve versus previously treated adolescents with an acute exacerbation of schizophrenia
Authors: Correll Christoph U. , Tocco Michael , Hsu Jay , Goldman Robert , Pikalov Andrei
Published: April 2022

Background

To evaluate the efficacy of short-term lurasidone in antipsychotic treatment-naïve (TN) adolescents with schizophrenia versus those treated previously (TP) with antipsychotics.

Methods

Patients aged 13–17 with schizophrenia, and a Positive and Negative Symptom Scale (PANSS) score ≥ 70 and < 120, were randomized to 6 weeks of double-blind treatment with lurasidone (40 or 80 mg/day) or placebo. In a post-hoc, pooled-dose analysis, efficacy was evaluated for TN (criteria: never received antipsychotic treatment) versus TP at the time of the study. Treatment response criteria: ≥20% reduction in PANSS total score.

Results

Altogether, 57 TN and 269 TP patients enrolled in the 6-week DB study. Mean endpoint change in PANSS total score was significantly greater for lurasidone versus placebo in both the TN group (−25.0 vs. -14.4; p < 0.02; effect size = 0.75), and in the TP group (−17.3 vs. -10.0; p < 0.001; effect size = 0.45); and responder rates were higher for lurasidone versus placebo in both the TN group 84.6% versus 38.9%; number needed to treat [NNT] = 3 and in the TP group (60% vs. 42%; NNT = 6). Rates of treatment-emergent adverse events, and mean changes in body weight and metabolic parameters were similar for the TN and TP groups.

Conclusions

In a 6-week, placebo-controlled trial, lurasidone demonstrated significant efficacy in adolescents with schizophrenia regardless of previous antipsychotic therapy status; however, the effect size was notably larger in the TN patient group. In both the TN and TP groups, minimal effects were noted on weight, metabolic parameters, or prolactin.
The Sounds of Siam
Authors: Thomas Downing A.
Published: April 2022

A series of diplomatic contacts between France and Siam was initiated in the 1660s primarily through missionary efforts and the expansion of France's global trade network. These diplomatic drives and their historical significance have been described by previous commentators in relation to Louis XIV's global ambitions and his efforts at royal image building. An aspect of these exchanges that has attracted relatively little commentary is the attention given by the participants and chroniclers to the sounds the French travelers experienced in Siam: how the sounds, musical or otherwise, that engaged their attention might have impeded or furthered diplomatic efforts. Within the context of the Louis XIV's attempts to expand France's influence in the world, the sounds and silences described by the French travelers provide additional insight about the diplomatic initiatives and how they understood, or misunderstood, Siam and its culture.

Une série de contacts diplomatiques entre la France et le Siam a commencé dans les années 1660, principalement à travers des activités missionnaires et l'expansion du réseau commercial de la France. Ces efforts diplomatiques et leur importance historique ont été l'objet d’études visant à comprendre les ambitions globales de Louis XIV et ses efforts à façonner une image royale. Un aspect de ces échanges qui a été moins étudié est l'attention donnée dans les commentaires et chroniques de l’époque à l'espace sonore siamois : comment les sons—musicaux ou autres—que les voyageurs ont rencontrés auraient empêché ou bien avancé leurs efforts diplomatiques. Dans le contexte de l'influence mondiale croissante de la France sous Louis XIV, les sons et les silences décrits par les voyageurs français offrent d'importants aperçus concernant les initiatives diplomatiques et les tentatives de comprendre le Siam et sa culture.
“Zouk Is the Only Medicine We Need”
Authors: Cohen Paul
Published: April 2022

This article demonstrates how the history of Kassav, the French Caribbean music group founded in 1979, sheds light on the cultural politics of French Caribbean music and the history of “global France.” It argues that Kassav's music represents an inventive cultural and commercial response to patterns of neocolonial and capitalist exclusion in the French Caribbean, one that drew on the islands' own cultural resources to fashion a new musical form, called zouk, that has had lasting influence. Kassav owes its commercial success in part to a global music industry hungry for new musics from postcolonial peripheries and to Paris's role as a world music capital. That Kassav was seen in metropolitan France as “Caribbean” or “world” music, rather than “French,” speaks to the historical and racial fault lines that obscure the Frenchness of the French Caribbean to many in the Hexagon.

Cet article analyse comment l'histoire de Kassav, le groupe musical antillais fondé en 1979, permet de mieux comprendre la politique culturelle de la musique des Antilles françaises ainsi que l'histoire « mondiale » de la France. La musique de Kassav représente une réponse culturelle et commerciale inventive à des structures d'exclusion néocoloniales et capitalistes dans les Antilles françaises, une réponse qui puisait dans les ressources culturelles propres aux îles, afin de façonner un nouveau genre de musique (le zouk) qui a exercé une influence importante. Kassav doit son succès commercial en partie à une industrie musicale mondialisée à l'affût de musiques issues des périphéries postcoloniales et au rôle de Paris comme capitale de la « musique du monde ». Que la musique de Kassav ait été perçue en France métropolitaine comme « antillaise » ou « du monde », plutôt que « française », témoigne des lignes de faille historiques et raciales qui occultent l'appartenance française des Antilles aux yeux de nombreux habitants de l'Hexagone.
Impact of Increasing Aspiration Catheter Size and Refinement of Technique: Experience of Over 1000 Strokes Treated With ADAPT
Authors: Al Kasab Sami , Almallouhi Eyad , Alawieh Ali , Chalhoub Reda , Sattur Mithun , Bass Eric , Pullmann Dominika , Porto Guilherme B , Lena Jonathan R. , Kicielinski Kimberly , Spiotta Alejandro M.
Published: April 2022

BACKGROUND:

We present longitudinal data regarding the outcomes and evolution of mechanical thrombectomy (MT) using a direct aspiration first pass technique.

OBJECTIVE:

To evaluate the impact of increasing aspiration catheter size.

METHODS:

This is a planned analysis of a prospective cohort study that enrolled all patients who underwent a direct aspiration first pass technique MT in a comprehensive stroke center from January 2013 to December 2020. We did exploratory analysis of the characteristics and outcomes of patients who had intracranial internal carotid artery or M1 segment of middle cerebral artery occlusion based on the aspiration catheter bore size (small [041, 054, 058, and 060 inch] vs medium [0.064 and 0.068 inch] and medium vs large [0.071, 0.072, and 0.074 inch]).

RESULTS:

During the 8-year study period, a total of 1004 patients were included. Median age was 69 years, 49% were female patients, and 60.6% were White. Symptomatic hemorrhagic transformation was observed in 47 patients (4.7%), and 366 patients (36.5%) achieved the modified Rankin scale of 0 to 2 at 90 days after the stroke. For patients with intracranial internal carotid artery or M1 occlusion, medium-bore aspiration catheters were more likely to achieve successful recanalization after first aspiration attempt (63.9% vs 51.4%, P = .015) and had a faster groin-to-reperfusion time (16 vs 20 minutes, P = .001) when compared with small-bore catheters. However, these differences were not significant when comparing medium-bore with large-bore catheters.

CONCLUSION:

Medium-bore catheters had better performance measures compared with small-bore catheters. However, large-bore catheters did not show significantly better performance results that suggest a plateau effect.
Association of Patient Frailty With Vestibular Schwannoma Resection Outcomes and Machine Learning Development of a Vestibular Schwannoma Risk Stratification Score
Authors: Tang Oliver Y. , Bajaj Ankush I. , Zhao Kevin , Rivera Perla Krissia M. , Ying Yu-Lan Mary , Jyung Robert W. , Liu James K.
Published: April 2022

BACKGROUND:

Patient frailty is predictive of higher neurosurgical morbidity and mortality. However, existing frailty measures are hindered by lack of specificity to neurosurgery.

OBJECTIVE:

To analyze the association between 3 risk stratification scores and outcomes for nationwide vestibular schwannoma (VS) resection admissions and develop a custom VS risk stratification score.

METHODS:

We identified all VS resection admissions in the National Inpatient Sample (2002-2017). Three risk stratification scores were analyzed: modified Frailty Index-5, modified Frailty Index-11(mFI-11), and Charlson Comorbidity Index (CCI). Survey-weighted multivariate regression evaluated associations between frailty and inpatient outcomes, adjusting for patient demographics, hospital characteristics, and disease severity. Subsequently, we used k-fold cross validation and Akaike Information Criterion–based model selection to create a custom risk stratification score.

RESULTS:

We analyzed 32 465 VS resection admissions. High frailty, as identified by the mFI-11 (odds ratio [OR] = 1.27, P = .021) and CCI (OR = 1.72, P < .001), predicted higher odds of perioperative complications. All 3 scores were also associated with lower routine discharge rates and elevated length of stay (LOS) and costs (all P < .05). Our custom VS-5 score (https://skullbaseresearch.shinyapps.io/vs-5_calculator/) featured 5 variables (age ≥60 years, hydrocephalus, preoperative cranial nerve palsies, diabetes mellitus, and hypertension) and was predictive of higher mortality (OR = 6.40, P = .001), decreased routine hospital discharge (OR = 0.28, P < .001), and elevated complications (OR = 1.59, P < .001), LOS (+48%, P < .001), and costs (+23%, P = .001). The VS-5 outperformed the modified Frailty Index-5, mFI-11, and CCI in predicting routine discharge (all P < .001), including in a pseudoprospective cohort (2018-2019) of 3885 admissions.

CONCLUSION:

Patient frailty predicted poorer inpatient outcomes after VS surgery. Our custom VS-5 score outperformed earlier risk stratification scores.
Mechanisms of sound production in deer mice (Peromyscus spp.)
Authors: Riede Tobias , Kobrina Anastasiya , Bone Landon , Darwaiz Tarana , Pasch Bret
Published: April 2022

Rodent diversification is associated with a large diversity of species-specific social vocalizations generated by two distinct laryngeal sound production mechanisms: whistling and airflow-induced vocal fold vibration. Understanding the relative importance of each modality to context-dependent acoustic interactions requires comparative analyses among closely related species. In this study, we used light gas experiments, acoustic analyses and laryngeal morphometrics to identify the distribution of the two mechanisms among six species of deer mice (Peromyscus spp.). We found that high frequency vocalizations (simple and complex sweeps) produced in close-distance contexts were generated by a whistle mechanism. In contrast, lower frequency sustained vocalizations (SVs) used in longer distance communication were produced by airflow-induced vocal fold vibrations. Pup isolation calls, which resemble adult SVs, were also produced by airflow-induced vocal fold vibrations. Nonlinear phenomena (NLP) were common in adult SVs and pup isolation calls, suggesting irregular vocal fold vibration characteristics. Both vocal production mechanisms were facilitated by a characteristic laryngeal morphology, including a two-layered vocal fold lamina propria, small vocal membrane-like extensions on the free edge of the vocal fold, and a singular ventral laryngeal air pocket known as the ventral pouch. The size and composition of vocal folds (rather than total laryngeal size) appears to contribute to species-specific acoustic properties. Our findings suggest that dual modes of sound production are more widespread among rodents than previously appreciated. Additionally, the common occurrence of NLP highlights the nonlinearity of the vocal apparatus, whereby small changes in anatomy or physiology trigger large changes in behavior. Finally, consistency in mechanisms of sound production used by neonates and adults underscores the importance of considering vocal ontogeny in the diversification of species-specific acoustic signals.
Extracellular N6-isopentenyladenosine (i6A) addition induces cotranscriptional i6A incorporation into ribosomal RNAs
Authors: Yakita Maya , Chujo Takeshi , Wei Fan-Yan , Hirayama Mayumi , Kato Koji , Takahashi Nozomu , Naganuma Kenta , Nagata Masashi , Kawahara Kenta , Nakayama Hideki , Tomizawa Kazuhito
Published: April 2022

N6-isopentenyladenosine (i6A), a modified adenosine monomer, is known to induce cell death upon its addition to the culture medium. However, the molecular fate of extracellularly added i6A has yet to be identified. Here we show that i6A addition to cell culture medium results in i6A incorporation into cellular RNA in several cell lines, including the 5-fluorouracil (5-FU)-resistant human oral squamous cell carcinoma cell line FR2-SAS and its parental 5-FU-sensitive cell line SAS. i6A was predominantly incorporated into 18S and 28S rRNAs, and i6A incorporation into total RNA was mostly suppressed by treating these cell lines with an RNA polymerase I (Pol I) inhibitor. i6A was incorporated into RNA even upon inactivation of TRIT1, the only cellular i6A-modifying enzyme. These results indicate that upon cellular uptake of i6A, it is anabolized to be used for Pol I transcription. Interestingly, at lower i6A concentrations, the cytotoxic effect of i6A was substantially more pronounced in FR2-SAS cells than in SAS cells. Moreover, in FR2-SAS cells, i6A treatment decreased the rate of cellular protein synthesis and increased intracellular protein aggregation, and these effects were more pronounced than in SAS cells. Our work provides insights into the molecular fate of extracellularly applied i6A in the context of intracellular nucleic acid anabolism and suggests investigation of i6A as a candidate for a chemotherapy agent against 5-FU-resistant cancer cells.
Το τοιχογραφικό έργο του Ράλλη Κοψίδη (1929-2010)
Authors: Μαμάης Νεκτάριος
Published: April 2022

Η συγκεκριμένη διδακτορική διατριβή αποτελεί την πρώτη αναλυτική και συνθετική παρουσίαση της συνολικής διαδρομής του τοιχογραφικού έργου του Ρ. Κοψίδη και την ένταξή της στο σύνολο της εικαστικής παραγωγής του. Γίνεται αισθητική σε βάθος ανάλυση της πρωτότυπης εικονογραφικής πρότασης του Ρ. Κοψίδη στον ι. ναό του Αγίου Παύλου στο Σαμπεζύ της Γενεύης. Εκκινώντας απο τα προσχέδια του και τις μελέτες γίνεται αισθητική και εικονογραφική αναλύσει των παραστάσεων που απαρτίζουν το εικονογραφικό σύνολο προκειμένου να φανεί η εικαστική σκέψη του δημιουργού. Αναφέρεται διεξοδικώς στην ιδιαιτερότητα της χρωματικής δομής και της απόδοσης της πλαστικότητας, στον σχεδιασμό και στην χρωματική οργάνωση των προσώπων, στον ζωγραφικό χώρο και στο πώς της απόδοσης του τοπίου.
Από το έντυπο στο ηλεκτρονικό παιδικό βιβλίο
Authors: Παγάνη Ευγενία
Published: April 2022

Η μελέτη αυτή καταγράφει τα χαρακτηριστικά της έντυπης και ηλεκτρονικής μορφής του παιδικού βιβλίου στο χώρο των εκδόσεων στην Ελλάδα, από το 1990 έως σήμερα, και εξερευνά τις τάσεις και τις προοπτικές των δύο μορφών. Η υλικότητα της έντυπης μορφής του παιδικού βιβλίου παρουσίασε αναρίθμητες διαφοροποιήσεις του σχήματος, του μεγέθους και των μεθόδων βιβλιοδεσίας της. Παράλληλα, ένα πλήθος καινοτομιών ενίσχυσε την υλικότητά της με οπτικοακουστικές και απτικές τροπικότητες. Από το 2010, οι νέες τεχνολογίες προσέφεραν στο παιδικό βιβλίο μια ακόμη μορφή. Οι Έλληνες εκδότες διέθεσαν την ηλεκτρονική μορφή παιδικού βιβλίου σε όλα τα γνωστά είδη και τους μορφότυπους, θέτοντας μια πρόκληση για το έντυπο παιδικό βιβλίο και την ανάγνωση των παιδιών. Τα αποτελέσματα της μελέτης αναδεικνύουν ότι κάθε επιλογή χαρακτηριστικού εξυπηρέτησε μια συγκεκριμένη λειτουργία στα πλαίσια της κάθε μορφής βιβλίου και συμπεραίνεται ότι η έντυπη και η ηλεκτρονική μορφή παιδικού βιβλίου θα συνυπάρχουν και θα εξελίσσονται παράλληλα, σε μια σχέση αλληλοσυμπλήρωσης και αμοιβαίας επιρροής.
Iterated nets of weakly contractive operators
Authors: Melentsov A. A.
Published: April 2022

Let K be a subset of a Banach space X. An operator T:K→K is said to be weakly contractive, if for every point x∈K there is a number C(x) and for any sequence {xn} with lim xn = x there exists a number N such that ∥Tx−Txn∥ ≤ C(x)∥x−xn∥  for all n>N. Every contractive operator is weakly contractive.The investigation of transfinite iteration processes leads to the study of the sequence space Σ(X) with Tikhonov's topology, to the study of fundamental and uniformly fundamental nets in the space Σ(X). In Theorem 2, by using regular operators summing divergent sequences, necessary and sufficient conditions for the existence of a fixed point of a weakly contractive operator are given. In particular, if T is a contractive operator, then by a theorem of Kirk and Massa [1], TΩ(x)=z for all x∈K, and by Theorem 2 T(z)=z.
Some notes on a convexity theorem for Cesàro-type families of summability methods
Authors: Müristaja Monika , Tali Anne
Published: April 2022

In this paper the convexity theorem well known for the family of Cesàro methods (see [4], Theorem 3.1) is transferred to the larger class of summability methods and applied to estimating the speed of summability.
Factors for absolute Riesz summability methods
Authors: Bor Hüseyin
Published: April 2022

We prove a theorem on |N,pn;δ|k summability factors, which extends a theorem of Bor [3] on |N,pn|k summability factors.
On a generalization of strong flatness
Authors: Laan Valdis
Published: April 2022

Strong flatness or flatness of right acts over a monoid S has been the topic of many papers on homological classification of monoids during the last decades. It has turned out to be useful to consider a property called condition (P), which lies strictly between these two properties. In this paper we define a new condition (O) and show that the class of S-acts satisfying this condition lies strictly between the classes of strongly flat S-acts and S-acts satisfying condition (P).
Counterexamples concerning topologization of spaces of strongly almost convergent sequences
Authors: Kolk Enno
Published: April 2022

Let λ be a sequence space, f a modulus function, and F=(fk) a sequence of moduli. We characterize the F-normability of the sequence space λ(F) for λ⊂l∞. In the special case if λ is the space sac0 of strongly almost convergent to zero sequences, we give two counterexamples concerning the topologization of various extensions of sac0(F) and sac0(f) considered by Nanda and others. We also correct a similar inaccuracy in a previous paper of the author.
On sequence spaces defined by a regularly varying modulus
Authors: Kolk Enno
Published: April 2022

Let λ be an F-seminormed solid sequence space. We characterize the F-seminormability of the sequence space λ(f)={(xk): (f(|xk|))∈λ} for a regularly varying modulus function f.
On r-convex sequence spaces defined by modulus functions
Authors: Soomer Virge
Published: April 2022

Let E be a sequence space and let F=(fk) be a sequence of r-convex modulus functions. The purpose of this paper is to study some properties of the spaces E(F) = {(ξk): (fk(|ξk|))∈E}.
Empty-cored sequences in Banach spaces
Authors: Iro Ain , Loone Leiki
Published: April 2022

The purpose of the present paper is to describe sequences in Banach spaces in terms of Knopp core. For matrix summability methods, the conditions forcore-shrinkingness are also given. In investigations of core inclusions and several other summability problems in Banach spaces it is vital to be aware ofelements with empty cores. Empty-cored sequences that remain empty-cored under transformation by an arbitrary regular matrix method are described.
Tauberian theorems for Bonsall core in sequence spaces
Authors: Loone Leiki , Tali Anne
Published: April 2022

The authors investigate cores K(x) of sequences x that are defined by different Bonsall functionals π. Two general Tauberian core theorems are proved. These are applied to special functionals π and matrix methods A. Some Tauberian conditions are generated with the theorems.
On commutativity of rings with conditions involving elements and the Jacobson radical
Authors: Quadri Murtaza A. , Khan Mohd. Shadab
Published: April 2022

Let R be an associative ring with unity 1, N the set of nilpotents, J the Jacobson radical of R and n>1 be a fixed integer. We prove that if R is n(n+1)-torsion free and satisfies the identity (xy)n=ynxn for all x,y ∈ R\ (N ∪ J), then R is commutative.
Approximation properties of certain linear positive operators of functions of two variables
Authors: Walczak Zbigniew
Published: April 2022

We introduce certain modified Szász-Mirakyan operators in polynomial and exponential weighted spaces of functions of two variables and we study the degree of approximation of functions by these operators.

Similar theorems for functions of one variable were given in [4] and [5].
Metric locally constant functions
Authors: Vâjâitu Marian , Zaharescu Alexandru
Published: April 2022

Given an ultrametric space E, a function f : E → [0,∞] is said to be metric locally constant (m.l.c.) provided that for any x ∈ E and any y in the open ball B(x,f(x)) one has f(x) = f(y). Given two ultrametric spaces E and F, we investigate the maps φ : E → F, for which f ° φ is m.l.c. for any m.l.c. function f : F → [0,∞].
The Wishart distributions on homogeneous cones
Authors: Andersson Steen A. , Wojnar G. Gerard
Published: April 2022

The classical family of Wishart distributions on a cone of positive definite matrices and its fundamental features are extended to a family of generalized Wishart distributions on a homogeneous cone using the theory of exponential families. The generalized Wishart distributions include all known families of Wishart distributions as special cases. The relations to graphical models and Bayesian statistics are indicated.
Alternative constructions of skewed multivariate distributions
Authors: Arnold Barry C. , Beaver Robert J.
Published: April 2022

A review of the construction of skewed multivariate normal distributions is presented. The review considers construction via (1) hidden truncation, (2) threshold models, (3) additive components and (4) a location and scale change for k variables beginning with k−1 independent standard normal variates and one univariate skew normal density. Extensiom to non-normal distributions have mainly used the hidden truncation approach. Unlike the normal case, the use of the three remaining techniques in constructing non-normal multivariate distributions leads to models distinct from those found using the hidden truncation approach. Examples of several tractable multivariate distributions using methods (1) and (3) are also presented.
Optimum chemical balance weighing design with diagonal matrix of errors based on balanced block designs
Authors: Ceranka Bronisław , Graczyk Małgorzata
Published: April 2022

The paper is studying the estimation problem of individual weights of objects using the chemical balance weighing design under the restriction on the number of times in which each object is weighed. Additionally, we assume that the errors are uncorrelated and they have different variances. There are given the lower bound of the variance of each of the estimated weights and the sufficient and necessary conditions under which this lower bound is attained. For the new construction method for optimum chemical balance weighing designs, we use the incidence matrices of the balanced incomplete block designs and the balanced bipartite weighing designs.
On risk processes with double barriers
Authors: Lokk Katrin , Pärna Kalev
Published: April 2022

We consider risk processes with two barriers. The risk process starts with an initial capital u>0 and the two barriers are set at 0 and v(>u). We are interested in finding the probability φ(u,v) that the risk process hits the upper barrier v before 0. Both cases of positive and negative relative safety loading are considered. Explicit formulae for φ(u,v) are obtained in the case of positive safety loading and in a special case of negative safety loading when the claims are exponentially distributed. For the general case of negative safety loading an integral equation is derived for φ(u,v), similar to the classical result for the case of a single barrier at 0.
Multivariate finite population inference under the assumption of linear pattern in the population
Authors: Rajaleid Kristiina
Published: April 2022

In this paper, a multivariate form of regression estimator for finite population inference is studied. Using Taylor linearization, the asymptotic covariance matrix of the estimator is derived. Properties of the estimator are examined. The results are illustrated by a simulation study.
Asymptotic formulas for a class of sums over consecutive Farey fractions
Authors: Zaharescu Alexandru
Published: April 2022

We provide asymptotic formulas, as Q → ∞, for a class of sums over consequtive Farey fractions of order Q, which are defined in terms of a given quadratic form.
On curvature tensors of non-symmetric affine connection
Authors: Minčić Svetislav M.
Published: April 2022

M. Prvanović [1], using polylinear mappings, has obtained four curvature tensors of non-symmetric affine connection on a differentiable manifold. In the present work we obtain eight new curvature tensors of this connection (Theorem 1) and prove that among these twelve curvature tensors only five are independent, and the others can be expressed in terms of them (Theorem 2).
On the degree of approximation of functions of two variables by some operators
Authors: Rempulska Lucyna , Skorupka Mariola
Published: April 2022

We introduce operators of Szász-Mirakyan and Baskakov type in polynomial weighted spaces of functions of two variables. We prove a theorem on the degree of approximation and a Voronovskaya type theorem for these operators. Similar results for Bernstein, Szász-Mirakyan and Baskakov operators of functions of one variable were given in [3-6].
Banach-Stone theorems for Banach bundles
Authors: Hõim Terje , Robbins David A.
Published: April 2022

We prove two Banach-Stone type theorems for section spaces of real Banach bundles. The first theorem assumes that the duals of all fibers are strictly convex, and the second considers disjointness-preserving operators. In each case, the result generalizes the corresponding Banach-Stone theorem for spaces of continuous vector-valued functions.
Uniform factorization for compact sets of operators acting from a Banach space to its dual space
Authors: Mikkor Kristel , Oja Eve
Published: April 2022

Let X be a Banach space. We prove a uniform factorization result that describes the factorization of compact sets of compact and weakly compact operators acting from X to X* via Hölder continuous homomorphisms having Lipschitz continuous inverses. This yields a similar factorization result for compact sets of 2-homogeneous polynomials.
Boundedness of superposition operators on the sequence spaces (w_0)_p(Phi)
Authors: Raidjõe Annemai
Published: April 2022

For a solid sequence space λ and a sequence of modulus functions Φ=(φk), let λ(Φ) = {x=(xk) : Φ(x)=(φk(|xk|))∈λ} . Provided another sequence of moduli Ψ = (ψk), we give necessary and sufficient conditions for the local boundedness and boundedness of superposition operators from (w0)p(Φ) into lq(Ψ) in the case 1≤p,q<∞.
Functorial properties of Cayley consructions
Authors: Knauer Ulrich , Wang Yanming , Zhang Xia
Published: April 2022

We describe the construction of the Cayley graph of a semigroup as a functor and investigate certain reflection and preservation properties of this functor. We also investigate it with respect to several product constructions including pullbacks.
The analysis of data from sample surveys under informative sampling
Authors: Eideh Abdulhakeem A.H. , Nathan Gad
Published: April 2022

Sampling designs for surveys are often complex and informative, in the sense that the selection probabilities are correlated with the variables of interest, even when conditioned on explanatory variables. In this case, conventional analysis that disregards the informativeness can be seriously biased, since the sample distribution differs from that of the population. We consider the relationships between the distribution of the sampled values and that of the population. Using different models for the conditional expectations of the inclusion probabilities, given the values of the variable of interest, we obtain the sample distributions and propose methods for estimation of their parameters. The results are applied to the analysis of longitudinal surveys, using an autoregressive model, and to surveys with two-stage cluster designs, with informative selection at each of the two stages.
On shift permutation invariance, covariance structures, and Toeplitz matrices
Authors: Nahtman Tatjana , Von Rosen Dietrich
Published: April 2022

The objective of this paper is to present a comprehensive study of shift permutation invariant covariance structures in linear models. It follows that the corresponding covariance matrices belong to the class of symmetric circular Toeplitz matrices. Results for the spectrum of shift permutation invariant covariance matrices of random factors in linear models are given. Among others the results are of use when reparametrization conditions are imposed in order to perform inference based on a unique set of parameters.
On strong summability of sequences
Authors: Soomer Virge , Tali Anne
Published: April 2022

We extend the notion of strong summability of sequences by matrix methods. Combining the notions of strong summability given by D. Borwein and I. J. Maddox we come to a more general notion. The properties of the extended strong summability are characterized and relations between strong and ordinary summabilities are described. The defined notion of strong summability is applied to certain families of summability methods, including some families of generalized Nörlund methods. Partial cases are the families of Cesàro and Euler-Knopp methods.
A conjecture of Bertino: from copulas to graph theory
Authors: Fredricks Gregory A.
Published: April 2022

In this article we prove a conjecture of Salvatore Bertino which centers on a study of the function

F(C) = \int_0^{1/2} V_C([t,t+1/2]^2) dt,

where C is a copula. This function, which arises in the study of the index of dissimilarity between two random variables (see Bertino 1977), is the integral of the C-volumes of the family of squares of sidelength 1/2 sliding from the lower left to the upper right along the ascending diagonal of the unit square. The conjecture made in 1999 is that the minimum value of F among the Bertino copulas is 1/8, which is the value of F at the Fr´echet lower bound. The conjecture is established by showing that a certain family of shuffles of M is dense in the set of Bertino copulas and then solving a problem in weighted graphs, which is equivalent to the conjecture in the restricted case.
Estimating main characteristics of processes with non-regular observations
Authors: Varatnitskaya Tatiana
Published: April 2022

In this paper the amplitude modulated version of a random process is investigated. Two cases have been taken into consideration.When the irregularities in observations are defined as a Poisson sequence, the estimators of the covariance function and the spectral density have been constructed. When the irregularities in observations are defined as a stationary random process in the wide sense, the estimators of the mean and the covariance function have been constructed. Statistical properties of the estimators have been studied.
Approximating the integrated tail distribution
Authors: Kaasik Ants , Pärna Kalev
Published: April 2022

We propose a natural approximation for the estimation of the distribution function of an integrated tail distribution of a subexponential distribution and prove that the approximation is almost surely uniformly convergent. The behaviour of the approximating error is studied using simulation. Knowing the distribution function of an integrated tail distribution is useful in the context of GI/G/1 queuewith heavy-tailed service times and in the context of risk process with heavy-tailed claims.
How Business Ethics Can Accommodate Disruptive Innovation Without Devolving Into Calvinball
Authors: Young Carson
Published: April 2022

Abraham Singer defends the Market Failures Approach (MFA) to business ethics from the objection that the MFA cannot account for the moral value of disruptive innovation. Singer argues that critics who attack the MFA on these grounds face a dilemma: either accept the MFA, along with its general prohibition on disruptive innovation, or reject the very idea that business and market competition should be understood as rule-governed activities at all. This commentary argues that the dilemma Singer poses to MFA critics is a false one.
Toward a Relational View of Organizational Innovation: Learning from Previous and Subsequent Stages of Innovation in Large Biopharmaceutical Firms, 1990–2006
Authors: Dahlin Eric
Published: April 2022

The paper draws on insights from relational sociology to develop a relational view of organizational innovation which suggests that feedback between stages of innovation may occur regardless of whether they precede one another, and activities at different stages may have reciprocal effects. Regression models based on a sample of 113 large biopharmaceutical firms demonstrate that firms with products in alternative stages of innovation are associated with having products in the focal stage. The key findings from the regression analysis are that product development generates positive feedback for product implementation andvice versa, and engaging in activities at multiple, alternative stages simultaneously generates benefits at the focal stage. The reciprocity between stages provides compelling evidence for the importance of viewing innovation through the lens of relational theory. Interviews with industry informants illustrate the fluidity that exists between innovation stages and the importance of fostering social interactions and communication between organizational members involved in innovation for fostering success across stages.
The impossibility of the triple helix
Authors: Andersson David Emanuel , Andersson Åke E
Published: April 2022

A dynamic model that distinguishes between slow and fast processes shows that a
triple helix model is impossible as a tool for promoting interdependencies among
science, industry and government. We present a theorem to demonstrate that a
triple helix strategy is logically impossible as a means of funding scientific
research in universities. In spite of this logical impossibility, national and
regional triple helix strategies to improve productivity and innovative capacity
have been favoured by politicians of almost every ideological stripe.
Coordination of science and industry by governments is not new; it harks back to
the mercantilism of seventeenth-century Britain and France. In the twentieth and
twenty-first centuries, triple helix policies have led to a short-term bias in
favour of applied technological research. Several examples, ranging from the
military use of scientists in World War II to Chinese high technology parks show
how triple helix strategies tilt playing fields, suppress academic freedom0 and
expose scientists to the whims of politicians.
The repression of mètis within digital organizations
Authors: Holford W. David
Published: April 2022

Numerous organizations are placing great emphasis on such techniques as evidence-based protocols to automation and artificial intelligence (AI) with the aim of improving efficiency and maximizing profitability. Such instrumental techniques attempt to formalize all manner of environmental phenomena through abstraction and categorization. They have also reduced organizational capability to deal with dynamic environmental complexities, uncertainties and ambiguities. The aim of this paper is to examine organizational approaches relying heavily on formalized/automated protocols in aviation, medicine and other professional domains targeted by AI development. Such approaches repress the human capability known asmètis, which organizations require to deal successfully with dynamic ambiguities in the form of unexpected emergencies.Mètisis briefly explained, and examples of organizational barriers preventing its manifestation are given.
A hand-up or a hand-out? An argument for concierge services for the development of innovation capacity in startups
Authors: Noble David , Charles Michael B , Keast Robyn
Published: April 2022

This study suggests that a concierge service, provided by governments, can assist startups to gain streamlined access to the services, capabilities and capital required to bring innovation efficiently and cost-effectively to market. It analyses a range of concierge models in five separate jurisdictions to determine best practice. The paper develops a rationale and working definition for a concierge service that will assist public sector managers to help young high-growth SMEs and startups to navigate the increasingly complex innovation ecosystem.
Restricting environmental damage resulting from economic activities: a Polanyian analysis
Authors: Senker Peter
Published: April 2022

Economic activities continue to cause considerable environmental damage. The extent of damage could be such that the environment in and around our planet will be affected, making survival difficult for human beings, for other animals, and for plants and insects. The paper reviews economic developments from the nineteenth century and how these have been influenced by orthodox economic theories. Markets are central to orthodox economics, and to policies which have been implemented recently to restrict global warming. Since the 1980s, policies based on orthodox economics and neoliberalism have been widely implemented by governments, and also by international organizations. Such policies are evaluated and found to be seriously inadequate. Studies of environmental implications of the development of two major sectors of the world economy follow. Policies which are concerned only to restrain climate change are unlikely to be adequate by themselves. Policies which take a holistic approach to considering all the important impacts of human economic activity on the environment have greater prospects of success. The paper concludes by suggesting research and analysis be undertaken urgently to assist with the design and implementation of more effective policies to reduce the damage to the environment caused by human economic activities.
Theoretical and numerical investigation of internal conical refraction of structured light beams
Authors: Caballero-Benítez S. F. , Hacyan S.
Published: April 2022

We present an ab initio numerical investigation of the internal conical refraction of structured light beams in a biaxial crystal. Starting from the solutions of the Fresnel equation, a theoretical analysis is developed without assuming any analytical approximation, thus obtaining a set of exact equations that can be solved by standard methods of integration for any impinging light beam. As examples of applications, we consider the particular cases of linearly and circularly polarized Gaussian and Bessel beams inside a KTP crystal. Numerical calculations follow the evolution of the refracted beam inside the crystal. It is seen that for realistic boundary conditions, a refraction cone appears in a certain range of distances within the crystal, and its shape is rather sensitive to the initial conditions.
Microwave-field sensing via electromagnetically induced absorption of Rb irradiated by three-color infrared lasers
Authors: You S. H. , Cai M. H. , Zhang S. S. , Xu Z. S. , Liu H. P.
Published: April 2022

A microwave electric field sensing has been set up based on a three-color electromagnetically induced absorption in rubidium vapor cell via cascading transitions. All transitions are irradiated by infrared lasers: a 780 nm laser servers as probe to monitor the optical transmittancy via transition 5S1/2→P3/2;, a 776 nm laser and a 1260 nm laser are used to couple the states 5P3/2 and 5D5/2 and states 5D5/2 and 44F7/2, respectively. We find that a frequency detuning ∼2π × ( − 40) MHz of the 776 nm dressing beam prefers to a better signal-to-noise ratio for the probe beam. The off-resonance greatly depresses the double resonance pumping effect. A demonstration measurement for the electric field of microwave 1.18988 GHz, corresponding to the coupling resonance between two adjacent Rydberg states 44F7/2 and 44F9/2, gives a sensitivity of

55.79
(
23
)

nVcm

−
1

/

Hz

and a smallest discernible electric field of 78.9(33) nVcm−1 in time scale of 500 ms.
Broadband and high-efficiency photonic spin-Hall effect with all-metallic metasurfaces
Authors: Cai Jixiang , Zhang Fei , Pu Mingbo , Xie Ting , Feng Xingdong , Yu Honglin , Luo Xiangang
Published: April 2022

In this paper, all-metallic reflective metasurfaces comprising S-shape streamline structures are proposed to achieve the photonic spin-Hall effect with average cross-polarization conversion efficiency exceeding ∼84% in the range of 8-14 µm. By comparing with all-metallic nanobricks, it is demonstrated that the electric field coupling could be enhanced by constructing a similar split ring resonator between adjacent unit elements to further improve its efficiency and bandwidth. As a proof of concept, the photonic spin Hall effect and spin-to-orbit angular momentum conversion could be observed by two metadevices with the maximum diffraction efficiency of ∼95.7%. Such an all-metallic configuration may provide a platform for various high-efficiency electromagnetic components, catenary optics, and practical applications.
Fast lightweight framework for time-of-flight super-resolution based on block compressed sensing
Authors: Zhang Wuyang , Song Ping , Wang Xuanquan , Zheng Zhaolin , Bai Yunjian , Geng Haocheng
Published: April 2022

Compressive time-of-flight (ToF) imaging for super-resolution (SR) has tremendous development potential owing to its cost-effectiveness and simplicity. However, existing compressive ToF methods are difficult to apply in practical situations because of their low efficiency and high data storage requirements. In this paper, we propose a fast and lightweight compressive ToF framework for SR. The block compressed sensing method, which shows distinct characteristics of high efficiency and low implementation cost, is introduced into the SR image acquisition and data transmission processes. Based on this framework, we establish a prototype system and verify it experimentally. Compared with existing compressive ToF systems, both the reconstruction time and data storage requirements are significantly decreased. We believe that this study provides a development direction for compressive ToF imaging and effective guidance for researchers realizing highly efficient and lightweight SR image reconstruction.
Single-shot cross-correlation of counter-propagating, short optical pulses using random quasi-phase-matching
Authors: Dorrer C. , Shaw J. L.
Published: April 2022

The single-shot cross-correlation of the short optical pulses generated by two laser facilities is acquired using random quasi-phase-matching of the counter-propagating beams in a disordered ferroelectric crystal. Transverse sum–frequency generation of the two counter-propagating pulses at different central wavelengths yields their time-dependent background-free cross-correlation after spectral filtering. Their relative delay is directly determined on every shot from the measured cross-correlation, making it a simple diagnostic for jitter studies and temporal characterization.
A genome-wide screen for variants influencing certolizumab pegol response in a moderate to severe rheumatoid arthritis population
Authors: White Ian R. , Kleinstein Sarah E. , Praet Christophe , Chamberlain Chris , McHale Duncan , Maia Jessica M. , Xie Pingxing , Goldstein David B. , Urban Thomas J. , Shea Patrick R.
Published: April 2022

Certolizumab pegol (CZP) is a PEGylated Fc-free tumor necrosis factor (TNF) inhibitor antibody approved for use in the treatment of rheumatoid arthritis (RA), Crohn’s disease, psoriatic arthritis, axial spondyloarthritis and psoriasis. In a clinical trial of patients with severe RA, CZP improved disease symptoms in approximately half of patients. However, variability in CZP efficacy remains a problem for clinicians, thus, the aim of this study was to identify genetic variants predictive of CZP response. We performed a genome-wide association study (GWAS) of 302 RA patients treated with CZP in the REALISTIC trial to identify common single nucleotide polymorphisms (SNPs) associated with treatment response. Whole-exome sequencing was also performed for 74 CZP extreme responders and non-responders within the same population, as well as 1546 population controls. No common SNPs or rare functional variants were significantly associated with CZP response, though a non-significant enrichment in the RA-implicated KCNK5 gene was observed. Two SNPs near spondin-1 and semaphorin-4G approached genome-wide significance. The results of the current study did not provide an unambiguous predictor of CZP response.