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Carbon dots (CDs) are a diverse and wide-reaching field of study which encompasses multiple scientific disciplines. This, along with their extensive applications, calls for the need to continually seek to improve their synthesis efficiency. To this end, we focused upon the effects of altering the heating method on the characteristics and quality of the final CD product. In our approach, two different versions of heating techniques were used including the common oven-based hydrothermal method and a microwave (MW)-assisted hydrothermal method. The MW-assisted heating involved the implementation of a pressure vessel (similar to oven hydrothermal vessel) for improved yield of luminescent CDs. We found that this MW method yielded CDs of bright intensity with comparable shape, size, and dispersity to that produced using conventional hydrothermal methods. Specifically, the CDs average particle diameters were determined to be between 1.8 and 2.0 nm for either method. The MW method also demonstrated certain advantages over the oven method in terms of required reaction time and particle yield. The total reaction and cooldown time was reduced by ∼75% (with ideal MW heating time) and an estimation of the average CDs particle density revealed that the MW method was able to produce approximately 1.2 times more particles than the oven method in less time. Correcting for the same processing time, larger yields are available in microwave synthesis. We were able to also demonstrate that both versions of synthesized CDs can serve as viable fluorescence probes for

Superconducting circuit testing and materials loss characterization requires robust and reliable methods for the extraction of internal and coupling quality factors of microwave resonators. A common method, imposed by limitations on the device design or experimental configuration, is the single-port reflection geometry, i.e. reflection-mode. However, impedance mismatches in cryogenic systems must be accounted for through calibration of the measurement chain while it is at low temperatures. In this paper, we demonstrate a data-based, single-port calibration using commercial microwave standards and a vector network analyzer (VNA) with samples at millikelvin temperature in a dilution refrigerator, making this method useful for measurements of quantum phenomena. Finally, we cross reference our data-based, single-port calibration and reflection measurement with over-coupled 2D- and 3D-resonators against well established two-port techniques corroborating the validity of our method., Comment: 12 pages, 17 figures

In this paper, novel representations of generalized inverses of rational matrices are developed. Therefore, a unified approach for the computation of 1,2,3 and 1,2,4 inverses and Moore-Penrose inverse of a given matrix A is considered. Full-rank QDR decomposition of a rational matrix is utilized to avoid the square roots of rational expressions in the evaluations, making the given algorithm very suitable for symbolic computations of generalized matrix inverses. Furthermore, we developed an algorithm for symbolic computation of the Moore-Penrose inverse of a polynomial matrix using the full-rank QDR decomposition, therefore maximizing the potential of using square root–free polynomial entries. Introduced algorithms are illustrated via numerical examples. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.

Cytokinesis is accomplished in higher plants by the phragmoplast, creating and con-ducting the cell plate to separate daughter nuclei by a new cell wall. The microtubule-severing enzyme p60-katanin plays an important role in the centrifugal expansion and timely disappearance of phragmoplast microtubules. Consequently, aberrant structure and delayed expansion rate of the phragmoplast have been reported to occur in p60-katanin mutants. Here, the consequences of p60-katanin malfunction in cell plate/daughter wall formation were investigated by transmission electron microscopy (TEM), in root cells of the fra2 Arabidopsis thaliana loss-of-function mutant. In addition, deviations in the chemical composition of cell plate/new cell wall were identified by immunolabeling and confocal microscopy. It was found that, apart from defective phragmoplast microtubule organization, cell plates/new cell walls also appeared faulty in structure, being une-venly thick and perforated by large gaps. In addition, demethylesterified homogalacturonans were prematurely present in fra2 cell plates, while callose content was significantly lower than in the wild type. Furthermore, KNOLLE syntaxin disappeared from newly formed cell walls in fra2 earlier than in the wild type. Taken together, these observations indicate that delayed cytokinesis, due to faulty phragmoplast organization and expansion, results in a loss of synchronization between cell plate growth and its chemical maturation. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

We are looking for an answer to the next challenging question: is the Newton iterative rule the only iterative method for computing generalized inverses with quadratic convergence? Our answer is that it is possible to find a class of quadratically convergent iterative methods containing the Newton method. To that end, we introduce and investigate a class of iterative methods for computing the outer inverse of a matrix. These methods arise from the second Penrose equation XAX= X and posses the linear or quadratic convergence. These iterative methods are determined by a real parameter β and a positive exponent p of an appropriate matrix power. The influence of the initial approximation are investigated both theoretically and numerically. A class of iterative method of the second order of convergence is defined by the most suitable case β= 1. A discussion on the stability of these methods, the order, and the behavior of the convergence and the error estimate are presented in details. Numerical tests are performed using Matlab gallery of test matrices during the computation of the Moore–Penrose inverse and the Drazin inverse. © 2019, The Royal Academy of Sciences, Madrid.

This cross sectional study aimed to compare the differences in psychopathology of Greek homicide and homicide attempters, patients with schizophrenia, with non violent individuals, suffering from schizophrenia. The study compared three Groups of 220 men, diagnosed with schizophrenia: (a) Group Α (Schizophrenia – No violence, (b) Group Β (Schizophrenia – with violence or violent crime), (c) Group C (Schizophrenia – not guilty by reason of insanity – violent crime). Several psychometric tools were used, such as M.I.N·I (Mini-International Neuropsychiatric Interview), PANSS scale (Positive and Negative Symptoms Scale). Most subjects suffered from paranoid schizophrenia. On factors such as demographic characteristics (i.e. current occupational status, living status), statistically significant findings were shown for Groups B and C vs Group A. Predisposing psychosocial factors, such as family conflicts and aggressiveness against family, were found to be statistically significant in differentiating violent versus nonviolent individuals with psychosis. They differed significantly in factors like history of juvenile delinquency, but also in the type of aggressiveness in general. These differences were confirmed on PANSS scale. In conclusion, the longer the history of aggressiveness is presented, the greater the chances are of individuals falling into Group C and it is possible to spend several years from the onset of the disease until the moment of crime. © 2018 Elsevier Ltd

Two finite recurrent procedures for computing {2,4} and {2,3} -inverses of a matrix are presented. Each of introduced methods exploits certain matrix product which includes the Moore–Penrose inverse of a symmetric matrix and a generalization of the Sherman-Morrison formula to the case of the Moore–Penrose inverse of a symmetrically rank one modified matrix. The computational complexity of the methods is analysed. In the essence, presented representations investigate dual methods with respect to these introduced in [Stanimirović PS, Katsikis VN, Pappas D, Computing {2,4} and {2,3}-inverses by using the Sherman-Morrison formula, Appl. Math. Comput. 2016;273:584–603]. © 2017 Informa UK Limited, trading as Taylor & Francis Group.

In this work we present some relationships between an EP matrix T, its Aluthge transform ∆(T) or the λ-Aluthge transform ∆ λ (T) and the Moore-Penrose inverse T † . We prove that the λ-Aluthge transform of T is also an EP matrix, and the same thing holds for ∆ λ (T) † and ∆ λ (T † ). Also, we explore the product ∆ λ (T)T, the connections between ∆(T) and T † as well as the reverse order law for generalized inverses which are associated with ∆ λ (T). Finally, it is verified that the ranges of T and ∆ λ (T) are equal in the case of EP matrices. © 2018, University of Nis. All rights reserved.

It has been known since the early days of quantum mechanics that hyperbolic secant pulses possess the unique property that they can perform cyclic evolution on two-level quantum systems independently of the pulse detuning. More recently, it was realized that they induce detuning- controlled phases without changing state populations. Here, we experimentally demonstrate the properties of hyperbolic secant pulses on superconducting transmon qubits and contrast them with the more commonly used Gaussian and square waves. We further show that these properties can be exploited to implement phase gates, nominally without exiting the computational subspace. This enables us to demonstrate the first microwave-driven Z-gates with a single control parameter, the detuning., Comment: 5 pages, 6 figures, added supplementary information

In the last few years, watermarking has become a powerful tool for data hiding and copyright protection. This paper presents a new noise-robust scheme for signal watermark embedding and extraction, applicable on the broad scientific field of information security, including speech and audio secure transmission. The proposed method employs bi-dimensional signal representations and the fractional Fourier transformation for watermark embedding and detection. An important feature of the current work is the introduction of matrix factorization and decomposition on these representations. The current scheme was also performed and evaluated for the case of an image. The efficiency and robustness of the procedure is proven experimentally. © 2015, SBMAC - Sociedade Brasileira de Matemática Aplicada e Computacional.

The algorithm for the symbolic computation of the Aluthge transform of a polynomial matrix is derived in this paper. For this purpose, the well-known PSVD by PQRD algorithm is considered to avoid square roots of polynomials in the Aluthge transform matrix. The algorithm for the symbolic computation of the polar decomposition for polynomial matrices is developed as well. Furthermore, the Aluthge transform for rank-one matrices defined by cross-products of vectors is symbolically calculated and presented in a closed formula. © 2017, Springer International Publishing.

OBJECTIVE: A recent high-density fine-mapping (ImmunoChip) study of genetic associations in rheumatoid arthritis (RA) identified 14 risk loci with validated genome-wide significance, as well as a number of loci showing associations suggestive of significance (P = 5 × 10(-5) < 5 × 10(-8)), but these have yet to be replicated. The aim of this study was to determine whether these potentially significant loci are involved in the pathogenesis of RA, and to explore whether any of the loci are associated with a specific RA serotype. METHODS: A total of 16 single-nucleotide polymorphisms (SNPs) were selected for genotyping and association analyses in 2 independent validation cohorts, comprising 6,106 RA cases and 4,290 controls. A meta-analysis of the data from the original ImmunoChip discovery cohort and from both validation cohorts was carried out, for a combined total of 17,581 RA cases and 20,160 controls. In addition, stratified analysis of patient subsets, defined according to their anti-cyclic citrullinated peptide (anti-CCP) antibody status, was performed. RESULTS: A significant association with RA risk (P < 0.05) was replicated for 6 of the SNPs assessed in the validation cohorts. All SNPs in the validation study had odds ratios (ORs) for RA susceptibility in the same direction as those in the ImmunoChip discovery study. One SNP, rs72928038, mapping to an intron of BACH2, achieved genome-wide significance in the meta-analysis (P = 1.2 × 10(-8), OR 1.12), and a second SNP, rs911263, mapping to an intron of RAD51B, was significantly associated in the anti-CCP-positive RA subgroup (P = 4 × 10(-8), OR 0.89), confirming that both are RA susceptibility loci. CONCLUSION: This study provides robust evidence for an association of RA susceptibility with genes involved in B cell differentiation (BACH2) and DNA repair (RAD51B). The finding that the RAD51B gene exhibited different associations based on serologic subtype adds to the expanding knowledge base in defining subgroups of RA.

A finite recursive procedure for computing 2,4 generalized inverses and the analogous recursive procedure for computing 2,3 generalized inverses of a given complex matrix are presented. The starting points of both introduced methods are general representations of these classes of generalized inverses. These representations are formed using certain matrix products which include the Moore-Penrose inverse or the usual inverse of a symmetric matrix product and the Sherman-Morrison formula for the inverse of a symmetric rank-one matrix modification. The computational complexity of the methods is analyzed. Defined algorithms are tested on randomly generated matrices as well as on test matrices from the Matrix Computation Toolbox. © 2015 Elsevier Inc. All rights reserved.

A previous study using cumulative genetic risk estimations in multiple sclerosis (MS) successfully tracked the aggregation of susceptibility variants in multi-case and single-case families. It used a limited description of susceptibility loci available at the time (17 loci). Even though the full roster of MS risk genes remains unavailable, we estimated the genetic burden in MS families and assess its disease predictive power using up to 64 single-nucleotide polymorphism (SNP) markers according to the most recent literature. A total of 708 controls, 3251 MS patients and their relatives, as well as 117 twin pairs were genotyped. We validated the increased aggregation of genetic burden in multi-case compared with single-case families (P¼4.14e03) and confirm that these data offer little opportunity to accurately predict MS, even within sibships (area under receiver operating characteristic (AUROC)¼0.59 (0.55, 0.53)). Our results also suggest that the primary progressive and relapsing-type forms of MS share a common genetic architecture (P¼0.368; difference being limited to that corresponding to ±2 typical MS-associated SNPs). We have confirmed the properties of individual genetic risk score in MS. Comparing with previous reference point for MS genetics (17 SNPs), we underlined the corrective consequences of the integration of the new findings from GWAS and meta-analysis.

A new method for the reconstruction of blurred digital images damaged by separable motion blur is established. The main attribute of the method is based on multiple applications of the least squares solutions of certain matrix equations which define the separable motion blur in conjunction with known image deconvolution techniques. The key feature of the proposed algorithms is reflected in the fact that they can be used only in symbiosis with other image restoration algorithms. © 2015 Predrag S. Stanimirović et al.

In this work, we introduce a new kind of generalized inverse, called the (Formula presented.) -restricted weighted Drazin inverse of (Formula presented.) with respect to a positive semi-definite/definite matrix (Formula presented.). The new approach proposed makes use of the normal Drazin equation of a nonconsistent matrix equation as the constraint set of the minimization. In addition, when (Formula presented.) is positive semi-definite, the minimal semi-norm solution is considered for all vectors belonging to (Formula presented.). We also show that the solution of the problem can be represented as a particular outer inverse solution. © 2014, © 2014 Taylor & Francis.

We follow the idea to find the solution of quadratic minimization problems restricted by linear constraints and to investigate underlying generalized inverses. A generalization of this approach leads to a new kind of outer generalized inverse, called the T-minimal A-constrained inverse of A (called the minimal (T, G) inverse of A shortly), with respect to a positive semidefinite/definite matrix T and a singular matrix G. The introduced generalized inverse is related with the minimization of the quadratic form ‹x, T x› under the constraint set defined by the consistent equation (GAx = Gb.). In this way, the generalized inverse arising from this constrained quadratic minimization problem gives a minimal T-semi-norm/norm solution of the system of linear equations GAx = Gb. The range and the null space of defined outer inverse are determined. Computational algorithms are defined and numerical experiments related with properties of the minimal (T, G) inverse are also presented. © 2015 Taylor & Francis.

We describe an ex-situ surface-cleaning procedure that is shown to reduce motional heating from ion-trap electrodes. This precleaning treatment, to be implemented immediately before the final assembly and vacuum processing of ion traps, removes surface contaminants remaining after the electrode-fabrication process. We incorporate a multi-angle ion-bombardment treatment intended to clean the electrode surfaces and interelectrode gaps of microfabricated traps. This procedure helps to minimize redeposition in the gaps between electrodes that can cause electrical shorts. We report heating rates in a stylus-type ion trap prepared in this way that are lower by one order of magnitude compared to a similar untreated stylus-type trap using the same experimental setup., 4 pages, 3 figures

Interstitial lung diseases (ILD), including those related to connective tissue disease (CTD), and idiopathic pulmonary fibrosis (IPF) carry high morbidity and mortality. Great efforts are under way to develop and investigate meaningful treatments in the context of clinical trials. However, efforts have been challenged by a lack of validated outcome measures and by inconsistent use of measures in clinical trials. Lack of consensus has fragmented effective use of strategies in CTD-ILD and IPF, with a history of resultant difficulties in obtaining agency approval of treatment interventions. Until recently, the patient perspective to determine domains and outcome measures in CTD-ILD and IPF had never been applied. Efforts described here demonstrate unequivocally the value and influence of patient involvement on core set development. Regarding CTD-ILD, this is the first OMERACT working group to directly address a manifestation/comorbidity of a rheumatic disease (ILD) as well as a disease not considered rheumatic (IPF). The OMERACT 11 proceedings of the CTD-ILD Working Group describe the forward and lateral process to include both the medical and patient perspectives in the urgently needed identification of a core set of preliminary domains and outcome measures in CTD-ILD and IPF.

We have generated frequency combs spanning 0.5 to 20 GHz in superconducting half wave resonators at T=3 K. Thin films of niobium-titanium nitride enabled this development due to their low loss, high nonlinearity, low frequency dispersion, and high critical temperature. The combs nucleate as sidebands around multiples of the pump frequency. Selection rules for the allowed frequency emission are calculated using perturbation theory and the measured spectrum is shown to agree with the theory. The sideband spacing is measured to be accurate to 1 part in 10 million. The sidebands coalesce into a continuous comb structure that has been observed to cover at least 6 octaves in frequency.

Rationale: Clinical trial design in interstitial lung diseases (ILDs) has been hampered by lack of consensus on appropriate outcome measures for reliably assessing treatment response. In the setting of connective tissue diseases (CTDs), some measures of ILD disease activity and severity may be confounded by non-pulmonary comorbidities. Methods: The Connective Tissue Disease associated Interstitial Lung Disease (CTD-ILD) working group of Outcome Measures in Rheumatology-a non-profit international organisation dedicated to consensus methodology in identification of outcome measures-conducted a series of investigations which included a Delphi process including >248 ILD medical experts as well as patient focus groups culminating in a nominal group panel of ILD experts and patients. The goal was to define and develop a consensus on the status of outcome measure candidates for use in randomised controlled trials in CTD-ILD and idiopathic pulmonary fibrosis (IPF). Results: A core set comprising specific measures in the domains of lung physiology, lung imaging, survival, dyspnoea, cough and health-related quality of life is proposed as appropriate for consideration for use in a hypothetical 1-year multicentre clinical trial for either CTD-ILD or IPF. As many widely used instruments were found to lack full validation, an agenda for future research is proposed. Conclusion: Identification of consensus preliminary domains and instruments to measure them was attained and is a major advance anticipated to facilitate multicentre RCTs in the field.

Anomalous heating of trapped atomic ions is a major obstacle to their use as quantum bits in a scalable quantum computer. The physical origin of this heating is not fully understood, but experimental evidence suggests that it is caused by electric-field noise emanating from the surface of the trap electrodes. In this study, we have investigated the role that adsorbates on the electrodes play by identifying contaminant overlayers, developing an in situ argon-ion beam cleaning procedure, and measuring ion heating rates before and after cleaning the trap electrodes' surfaces. We find a reduction of two orders of magnitude in heating rate after cleaning., Comment: 7 pages, 1 figure

A case of a neonate with congenital chylous ascites resulting from primary lymphatic dysplasia is described. The baby also presented with a sludge ball in the gallbladder that eventually progressed to gallstones. The association of chylous ascites with cholelithiasis in this neonate is discussed. Journal of Perinatology (2010) 30, 227-230; doi: 10.1038/jp.2009.128

This paper presents a fast computational method that finds application in a broad scientific field such as digital image restoration. The proposed method provides a new approach to the problem of image reconstruction by using the Moore-Penrose inverse. The resolution of the reconstructed image remains at a very high level but the main advantage of the method was found on the computational load that has been decreased considerably compared to the classic techniques. © 2009 Spiros Chountasis et al.

Gen Hosp Psychiatry

Schizophr Res

Although Josephson junction qubits show great promise for quantum computing, the origin of dominant decoherence mechanisms remains unknown. We report Rabi oscillations for an improved phase qubit, and show that their coherence amplitude is significantly degraded by spurious microwave resonators. These resonators arise from changes in the junction critical current produced by two-level states in the tunnel barrier. The discovery of these high frequency resonators impacts the future of all Josephson qubits as well as existing Josephson technologies. We predict that removing or reducing these resonators through materials research will improve the coherence of all Josephson qubits., Submitted to Physical Review Letters

This note describes the improvements performed to the University of Athens Muon Drift Tube assembly line. All implemented QA/QC tests are described. Experience and results of the performance are extracted from the assembly of more than 10% of the BIS tubes.

Energetic ion bombardment has been coupled with Multiphoton Resonance Ionization Spectroscopy to yield a powerful tool for surface analysis. This technique will be used to search for and examine he double-beta decay of Xe to Ba.

Introduction Amebiasis is a parasitic disease caused by Entamoeba histolytica. It most commonly results in asymptomatic colonization of the gastrointestinal tract, but some patients develop intestinal invasive or extra-intestinal diseases. Liver abscess is the most common extra-intestinal manifestation. The large number of clinical presentations of amebic liver abscess makes the diagnosis very challenging in non-endemic countries. Late diagnosis of the amebic abscess may lead to perforation and amebic peritonitis, resulting in high mortality rates. Case presentation This report describes a 37-year-old white man, suffering from hepatitis B, with a gigantic amebic liver abscess presenting as an acute abdomen due to its rupture. Rapid deterioration of the patient's condition and acute abdomen led to an emergency operation. A large volume of free fluid together with debris was found at the moment of entry into the peritoneal cavity because of a rupture of the hepatic abscess at the position of the segment VIII. Surgical drainage of the hepatic abscess was performed; two wide drains were placed in the remaining hepatic cavities and one on the right hemithorax. The patient was hospitalized in the ICU for 14 days and for another 14 days in our department. The diagnosis of amebic abscess was made by the pathologists who identified E. histolytica in the debris. Conclusion Acute abdomen due to a ruptured amebic liver abscess is extremely rare in western countries where the parasite is not endemic. Prompt diagnosis and treatment are fundamental to preserving the patient's life since the mortality rates remain extremely high when untreated, even nowadays.