We studied clinical and immunological outcome of Covid-19 in consecutive CLL patients from a well-defined area during month 1–13 of the pandemic. Sixty patients (median age 71 y, range 43–97) were identified. Median CIRS was eight (4–20). Patients had indolent CLL (n = 38), had completed (n = 12) or ongoing therapy (n = 10). Forty-six patients (77%) were hospitalized due to severe Covid-19 and 11 were admitted to ICU. Severe Covid-19 was equally distributed across subgroups irrespective of age, gender, BMI, CLL status except CIRS (p < 0.05). Fourteen patients (23%) died; age ≥75 y was the only significant risk factor (p < 0.05, multivariate analysis with limited power). Comparing month 1–6 vs 7–13 of the pandemic, deaths were numerically reduced from 32% to 18%, ICU admission from 37% to 15% whereas hospitalizations remained frequent (86% vs 71%). Seroconversion occurred in 33/40 patients (82%) and anti-SARS-CoV-2 antibodies were detectable at six and 12 months in 17/22 and 8/11 patients, respectively. Most (13/17) had neutralizing antibodies and 19/28 had antibodies in saliva. SARS-CoV-2-specific T-cells (ELISpot) were detected in 14/17 patients. Covid-19 continued to result in high admission even among consecutive and young early- stage CLL patients. A robust and durable B and/or T cell immunity was observed in most convalescents.
Purpose This study aims to apply the stimulus-organism-response framework to uncover the underlying mechanism by which the perceived helpfulness of online customer reviews (OCRs) drives behavioural intentions in mobile travel app commerce. Also, the current study explores how vendor-driven perceived usefulness of a product and its attributes influence the mediated relationship between perceived helpfulness of OCRs (OCRs helpfulness) and behavioural intentions. Design/methodology/approach The online survey (n = 151) was used to collect the data. The authors used structural equation modelling and the bias-corrected bootstrap method to test the proposed conceptual model for mediation and moderated-mediation effect. Findings Findings indicate that the perceived OCRs helpfulness has an indirect positive effect, via trust and attitude, on travel app downloading intention. Moreover, results suggest that the presence of vendor cues (vendor-generated informational content about a travel app) does not significantly moderate the mediating effect of perceived OCRs helpfulness on travel app downloading intention. Originality/value The present study reinforces the applicability of the warranting principle in the context of travel app commerce by exploring the relative effectiveness of customer-generated and vendor-generated informational content in influencing travel app downloading intention.
Intra-abdominal infections (IAIs) are common surgical emergencies and have been reported as major contributors to non-trauma deaths in hospitals worldwide. The cornerstones of effective treatment of IAIs include early recognition, adequate source control, appropriate antimicrobial therapy, and prompt physiologic stabilization using a critical care environment, combined with an optimal surgical approach. Together, the World Society of Emergency Surgery (WSES), the Global Alliance for Infections in Surgery (GAIS), the Surgical Infection Society-Europe (SIS-E), the World Surgical Infection Society (WSIS), and the American Association for the Surgery of Trauma (AAST) have jointly completed an international multi-society document in order to facilitate clinical management of patients with IAIs worldwide building evidence-based clinical pathways for the most common IAIs. An extensive non-systematic review was conducted using the PubMed and MEDLINE databases, limited to the English language. The resulting information was shared by an international task force from 46 countries with different clinical backgrounds. The aim of the document is to promote global standards of care in IAIs providing guidance to clinicians by describing reasonable approaches to the management of IAIs.
This paper presents two schemes to jointly estimate parameters and states of discrete-time nonlinear systems in the presence of bounded disturbances and noise. The parameters are assumed to belong to a known compact set. Both schemes are based on sampling the parameter space and designing a state observer for each sample. A supervisor selects one of these observers at each time instant to produce the parameter and state estimates. In the first scheme, the parameter and state estimates are guaranteed to converge within a certain margin of their true values in finite time, assuming that a sufficiently large number of observers is used and a persistence of excitation condition is satisfied in addition to other observer design conditions. This convergence margin is constituted by a part that can be chosen arbitrarily small by the user and a part that is determined by the noise levels. The second scheme exploits the convergence properties of the parameter estimate to perform subsequent zoom-ins on the parameter subspace to achieve stricter margins for a given number of observers. The strengths of both schemes are demonstrated using a numerical example.
The aim of this research is to determine the relaxation and creep modulus of 3D printed materials, and the numerical research is based on the finite volume method. The basic material for determining these characteristics is ABS (acrylonitrile butadiene styrene) plastic as one of the most widely used polymeric materials in 3D printing. The experimental method for determining the relaxation functions involved the use of a creep test, in which a constant increase of the stress of the material was performed over time to a certain predetermined value. In addition to this test, DMA (dynamic mechanical analysis) analysis was used. Determination of unknown parameters of relaxation functions in analytical form was performed on the basis of the expression for the storage modulus in the frequency domain. The influence of temperature on the values of the relaxation modulus is considered through the determination of the shift factor. Shift factor is determined on the basis of a series of tests of the relaxation function at different constant temperatures. The shift factor is presented in the form of the WLF (Williams-Landel-Ferry) equation. After obtaining such experimentally determined viscoelastic characteristics with analytical expressions for relaxation modulus and shift factors, numerical analysis can be performed. For this numerical analysis, a mathematical model with an incremental approach was used, as developed in earlier works although with a certain modification. In the experimental analysis, the analytical expression for relaxation modulus in the form of the Prony series is used, and since it is the sum of exponential functions, this enables the derivation of a recursive algorithm for stress calculation. Numerical analysis was performed on several test cases and the results were compared with the results of the experiment and available analytical solutions. A good agreement was obtained between the results of the numerical simulation and the results of the experiment and analytical solutions.
In March 2019, the World Health Organization (WHO) declared that humanity was entering a global pandemic phase. This unforeseen situation caught everyone unprepared and had a major impact on several professional categories that found themselves facing important ethical dilemmas. The article revolves around the category of biomedical and clinical engineers, which were among those most involved in dealing with and finding solutions to the pandemic. In hindsight, the major issues brought to the attention of biomedical engineers have raised important ethical implications, such as the allocation of resources, the responsibilities of science and the inadequacy and non-universality of the norms and regulations on biomedical devices and personal protective equipment. These issues, analyzed one year after the first wave of the pandemic, come together in the appeal for responsibility for thought, action and, sometimes, even silence. This highlights the importance of interdisciplinarity and the definitive collapse of the Cartesian fragmentation of knowledge, calling for the creation of more fora, where this kind of discussions can be promoted.
OBJECTIVE Although literary depiction of brachial plexus injury can be traced to Homer's Iliad, there is a scientific consensus that the first clinical description of brachial plexus palsy was not documented until the British physician Smellie reported it in the 18th century. However, the authors' recent review of the Syriac Book of Medicines (12th century) has uncovered a much earlier clinical documentation. METHODS For this historical vignette, the authors reviewed the historical and anatomical literature regarding earlier descriptions of brachial plexus anatomy and pathology, including a thorough analysis of the Syriac Book of Medicines (attributed to an unknown Syriac physician in the Middle Ages) and Galen's On Anatomical Procedures and On the Usefulness of the Parts of the Body. RESULTS Building on the galenic tradition with reference to independent dissections, the Syriac physician discussed nervous system anatomy and the clinical localization of neurological injuries. He described a patient who, after initial pulmonary symptoms, developed upper-extremity weakness more pronounced in the proximal muscles. His anatomical correlation placed the injury "where the nerves issue from the first and second muscles between the ribs" (scalene muscles), are "mixed," and "spread through many parts." The patient's presentation and recovery raise the possibility of Parsonage-Turner syndrome. The anatomical description of the brachial plexus is in line with Galen's earlier account and step-by-step surgical exposure, which the authors reviewed. They also examined Ibn Ilyas' drawing of the brachial plexus, which is believed to be a copy of the earliest artistic representation of the plexus. CONCLUSIONS Whereas the Middle Ages were seen as a period of scientific stagnation from a Western perspective, Galen's teachings continued to thrive and develop in the East. Syriac physicians were professional translators, clinicians, and anatomists. There is evidence that brachial plexus palsy was documented in the Syriac Book of Medicines 6 centuries before Smellie.
Clival chordomas are rare malignant behaving tumors that grow, locally invade, metastasize, and seed, and they have a high recurrence rate.1,2 The longest disease control is achieved by radical resection followed by high doses of radiation therapy, commonly proton beam.3 To achieve radical tumor removal, multiple surgical procedures through different approaches might be required.4 Since the chordoma's origin is, and remains, extradural, an extradural approach is preferred, and can lead to intradural extension. Anterior approach is frequently utilized to remove the midline-located tumor and the eroded clivus.5 Several midline approaches were utilized, including the transbasal, transfacial, transcervical, open door, and Lefort's maxillotomies1; however, the same tumor removal can be achieved with a simple extension of the trans-sphenoidal approach, by resecting the anterior maxillary wall, of the contralateral to the lesion preponderant side.5 This approach coupled with the use of neuronavigation on mobile head and endoscopic-assisted technique allowed to achieve a wide and direct exposure, with the ability to resect extra- and intradural tumors.2,5 Lately, the endonasal endoscopic technique became popular as an alternative4; however, we found a great advantage in the ability to combine the stereoscopic microsurgical technique with the endoscopic dissection, in addition to avoiding the extensive nasal dissection and its complications. We present a case of a 63-yr old woman with an upper clivus chordoma compressing the brainstem who underwent a gross total resection by endoscopic-assisted microscopic techniques through an anterior clivectomy approach. Patient consented to the procedure and publication of her images.
Kale (Brassica oleracea var. acephala) is known as a vegetable with good tolerance of environmental stress and numerous beneficial properties for human health, which are attributed to different phytochemicals. In the present study, investigation of how low temperatures affect proline, pigments and specialized metabolites content was performed using 8-weeks old kale plants subjected to chilling (at 8 °C, for 24 h) followed by short freezing (at −8 °C, for 1 h after previous acclimation at 8 °C, for 23 h). Plants growing at 21 °C served as a control. In both groups of plants (exposed to low temperatures and exposed to short freezing) a significant increase in proline content (14% and 49%, respectively) was recorded. Low temperatures (8 °C) induced an increase of pigments (total chlorophylls 7%) and phytochemicals (phenolic acids 3%; flavonoids 5%; carotenoids 15%; glucosinolates 21%) content, while exposure to freezing showed a different trend dependent upon observed parameter. After freezing, the content of chlorophylls, carotenoids, and total phenolic acids retained similar levels as in control plants and amounted to 14.65 ± 0.36 mg dw g−1, 2.58 ± 0.05 mg dw g−1 and 13.75 ± 0.07 mg dw CEA g−1, respectively. At the freezing temperature, total polyphenol content increased 13% and total flavonoids and glucosinolates content decreased 21% and 54%, respectively. Our results suggest that acclimatization (23 h at 8 °C) of kale plants can be beneficial for the accumulation of pigments and phytochemicals, while freezing temperatures affect differently specialized metabolite synthesis. The study suggests that growing temperature during kale cultivation must be considered as an important parameter for producers that are orientated towards production of crops with an increasing content of health-related compounds.
To investigate solutions of (near-)optimal control problems, we extend and exploit a notion of homogeneity recently proposed in the literature for discrete-time systems. Assuming the plant dynamics is homogeneous, we first derive a scaling property of its solutions along rays provided the sequence of inputs is suitably modified. We then consider homogeneous cost functions and reveal how the optimal value function scales along rays. This result can be used to construct (near-)optimal inputs on the whole state space by only solving the original problem on a given compact manifold of a smaller dimension. Compared to the related works of the literature, we impose no conditions on the homogeneity degrees. We demonstrate the strength of this new result by presenting a new approximate scheme for value iteration, which is one of the pillars of dynamic programming. The new algorithm provides guaranteed lower and upper estimates of the true value function at any iteration and has several appealing features in terms of reduced computation. A numerical case study is provided to illustrate the proposed algorithm.
In this paper, we study and present a management and orchestration framework for vehicular communications, which enables service continuity for the vehicle via an optimized application-context relocation approach. To optimize the transfer of the application-context for Connected and Automated Mobility (CAM) services, our MEC orchestrator performs prediction of resource availability in the edge infrastructure based on the Long Short-Term Memory (LSTM) model, and it makes a final decision on relocation by calculating the outcome of a Multi-Criteria Decision-Making (MCDM) algorithm, taking into account the i) resource prediction, ii) latency and bandwidth on the communication links, and iii) geographical locations of the vehicle and edge hosts in the network infrastructure. Furthermore, we have built a proof-of-concept for the orchestration framework in a real-life distributed testbed environment, to showcase the efficiency in optimizing the edge host selection and application context relocation towards achieving continuity of a service that informs vehicle about the driving conditions on the road.
Aims and objectives/purpose/research questions: This article aims to explore the link between linguistic subordination and linguistic inferiority complexes in the context of English as a second language (ESL) migrants in Australia. We address the following research questions: (a) To what extent and how do ESL migrants in Australia suffer from linguistic subordination? (b) To what extent and how is this linguistic subordination linked to linguistic inferiority complexes for ESL-migrants in Australia? (c) What are the main social implications of the link between linguistic subordination and linguistic inferiority complexes for ESL migrants? Design/methodology/approach: The study involved the participation of 150 participants who were observed using linguistic ethnography. The participants engaged in interviews and focus group discussions so that we could explore the psychological consequences of linguistic subordination that they encountered. Data and analysis: The interviews and focus group discussions were transcribed and analysed with consideration to the context, as well as the participants’ utterances and paralanguage. The study followed alternative quality criteria. Findings/conclusions: Many ESL migrants in Australia face linguistic subordination for the way they speak English. Consequently, these migrants suffer from linguistic inferiority complexes – psychological and emotional damages, which result in self-marginalisation, self-vindication, loss of sense of belonging, social withdrawal, fear, anxiety and the erosion of self-confidence. We find that there is a direct link between linguistic subordination and linguistic inferiority complexes. Originality: This article addresses a gap that exists regarding the link between linguistic subordination and the development of linguistic inferiority complexes, discusses how this has real-life consequences for ESL migrants, and explores how this may be overcome. Significance/implications: ESL migrants need support so that they can cope with their experiences of linguistic subordination, thus helping them better deal with issues related to linguistic inferiority complexes. In addition, the broader society needs greater education on how their comments and actions can affect the wellbeing of others.
This study evaluated the phytoremediation potential of eight native plant species on heavy metal polluted soils along the Spreča river valley (the northeast region of Bosnia and Herzegovina). Plants selected for screening were: ryegrass (Lolium perenne L.), common nettle (Urtica dioica L.), mugwort (Artemisia vulgaris L.), wild mint (Mentha arvensis L.), white clover (Trifolium repens L.), alfalfa (Medicago sativa L.), dwarf nettle (Urtica urens L.) and yarrow (Achillea millefolium L.). All aboveground parts of selected native plants and their associated soil samples were collected and analysed for total concentration of Ni, Cr, Cd, Pb, Zn and Cu. The bioaccumulation factor for each element was also calculated. The levels of Cr (90.9–171.1 mg/kg) and Ni (80.1–390.5 mg/kg) in the studied soil plots were generally higher than limits prescribed by European standards, indicating that the soils in the Spreča river valley are polluted by Cr and Ni. Among the eight screened plant species, no hyperaccumulators for toxic heavy metals Ni, Cr, Cd and Pb were identified. However, the concentrations of toxic heavy metals in the above-ground parts of Artemisia vulgaris L. and Trifolium repens L. were significantly higher than in the other studied plants, indicating that both plant species are useful for heavy metal removal.
Sweet cherry (Prunus avium L.) is a temperate fruit species whose production might be highly impacted by climate change in the near future. Diversity of plant material could be an option to mitigate these climate risks by enabling producers to have new cultivars well adapted to new environmental conditions. In this study, subsets of sweet cherry collections of 19 European countries were genotyped using 14 SSR. The objectives of this study were (i) to assess genetic diversity parameters, (ii) to estimate the levels of population structure, and (iii) to identify germplasm redundancies. A total of 314 accessions, including landraces, early selections, and modern cultivars, were monitored, and 220 unique SSR genotypes were identified. All 14 loci were confirmed to be polymorphic, and a total of 137 alleles were detected with a mean of 9.8 alleles per locus. The average number of alleles (N = 9.8), PIC value (0.658), observed heterozygosity (Ho = 0.71), and expected heterozygosity (He = 0.70) were higher in this study compared to values reported so far. Four ancestral populations were detected using STRUCTURE software and confirmed by Principal Coordinate Analysis (PCoA), and two of them (K1 and K4) could be attributed to the geographical origin of the accessions. A N-J tree grouped the 220 sweet cherry accessions within three main clusters and six subgroups. Accessions belonging to the four STRUCTURE populations roughly clustered together. Clustering confirmed known genealogical data for several accessions. The large genetic diversity of the collection was demonstrated, in particular within the landrace pool, justifying the efforts made over decades for their conservation. New sources of diversity will allow producers to face challenges, such as climate change and the need to develop more sustainable production systems.
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