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Wire and arc additive manufacturing of aluminium-ceramic composites shows great potential to produce high strength materials. By incorporation of nanoparticles in the feedstock wire, fine-grained material with low susceptibility for solidification cracking and enhanced strength can be obtained. In fact, this study utilised the novel screw extrusion method to prepare an aluminium alloy containing TiC nanoparticles. The commercial aluminium alloy AA5183 was selected for WAAM to assess and benchmark the effects of screw extrusion and TiC. The materials have been assessed in terms of microstructure, porosity content and mechanical properties. The presence of TiC reduced the average grain diameter by 70%, while Vickers hardness increased with 13%. However, number of pores per unit volume increased by one order of magnitude. The porosity is believed to stem from hydrogen introduced in the AA5183-material through screw extrusion processing, in addition to hydrogen trapping and pore nucleation on TiC nanoparticles.

Oral squamous cell carcinoma (OSCC) is the most common head and neck cancer. Although the oral cavity is an easily accessible area for visual examination, the OSCC is more often detected at an advanced stage. The global prevalence of OSCC is around 6%, with increasing trends posing a significant health problem due to the increase in morbidity and mortality. The oral cavity microbiome has been the target of numerous studies, with findings highlighting the significant role of dysbiosis in developing OSCC. Dysbiosis can significantly increase pathobionts (bacteria, viruses, fungi, and parasites) that trigger inflammation through their virulence and pathogenicity factors. In contrast, chronic bacterial inflammation contributes to the development of OSCC. Pathobionts also have other effects, such as the impact on the immune system, which can alter immune responses and contribute to a pro-inflammatory environment. Poor oral hygiene and carbohydrate-rich foods can also increase the risk of developing oral cancer. The risk factors and mechanisms of OSCC development are not yet fully understood and remain a frequent research topic. For this reason, this narrative review concentrates on the issue of dysbiosis as the potential cause of OSCC, as well as the underlying mechanisms involved.

Aggregatibacter actinomycetemcomitans ( A. actinomycetecomitans ) is a Gram-negative bacterial species that is an essential component of the oral microbiota. Due to its aggregative properties, it plays a role in the pathogenesis of human diseases. The presence of the surface proteins Fim, Briae, and microvesicles enables the bacterium to adhere to the epithelial surface and the tooth's surface. The presence of leukotoxin A (LtxA), which plays an important role in the pathogenicity of the bacterium, has been associated with both periodontitis and the etiology of rheumatoid arthritis (RA). A. actinomycetecomitans is also associated with several other systemic diseases and complications, such as endocarditis and different abscesses. In addition to leukotoxin A, A. actinomycetecomitans possesses several different virulence factors, including bacteriocins, chemotaxis inhibitory factors, cytotoxic factors, Fc-binding proteins, immunosuppressive factors, lipopolysaccharide collagenase, fibroblast inhibitory factors, antibiotic resistance determinants, adhesins, invasive factors and factors that inhibit the function of polymorphonuclear leukocytes. The ability of A. actinomycetemcomitans lipopolysaccharide to induce macrophages to secrete the interleukins IL-1, IL-1β, and tumor necrosis factor (TNF) is of considerable importance. The primary etiologic factor in the pathogenesis of periodontal disease is the oral biofilm colonized by anaerobic bacteria. Among these, A. actinomycetemcomitans occupies an important place as a facultative anaerobic bacterium. In addition, A. actinomycetemcomitans possesses many virulence factors that contribute to its potential to cause cancer. This article provides an overview of the virulence factors of A. actinomycetecomitans and its association with various systemic diseases, its oncogenic potential, and the treatment options for infections caused by A. actinomycetecomitans .

Radioactivity is a process in which the nuclei of unstable atoms spontaneously decay, producing other nuclei and releasing energy in the form of ionizing radiation in the form of alpha (α) and beta (β) particles as well as the emission of gamma (γ) electromagnetic waves. People may be exposed to radiation in various forms, as casualties of nuclear accidents, workers in power plants, or while working and using different radiation sources in medicine and health care. Acute radiation syndrome (ARS) occurs in subjects exposed to a very high dose of radiation in a very short period of time. Each form of radiation has a unique pathophysiological effect. Unfortunately, higher organisms-human beings-in the course of evolution have not acquired receptors for the direct "capture" of radiation energy, which is transferred at the level of DNA, cells, tissues, and organs. Radiation in biological systems depends on the amount of absorbed energy and its spatial distribution, particularly depending on the linear energy transfer (LET). Photon radiation with low LET leads to homogeneous energy deposition in the entire tissue volume. On the other hand, radiation with a high LET produces a fast Bragg peak, which generates a low input dose, whereby the penetration depth into the tissue increases with the radiation energy. The consequences are mutations, apoptosis, the development of cancer, and cell death. The most sensitive cells are those that divide intensively-bone marrow cells, digestive tract cells, reproductive cells, and skin cells. The health care system and the public should raise awareness of the consequences of ionizing radiation. Therefore, our aim is to identify the consequences of ARS taking into account radiation damage to the respiratory system, nervous system, hematopoietic system, gastrointestinal tract, and skin.

Candida albicans is a commensal fungal species that commonly colonizes the human body, but it is also a pervasive opportunistic pathogen in patients with malignant diseases. A growing body of evidence suggests that this fungus is not only coincidental in oncology patients, but may also play an active role in the development of cancer. More specifically, several studies have investigated the potential association between C. albicans and various types of cancer, including oral, esophageal, and colorectal cancer, with a possible role of this species in skin cancer as well. The proposed mechanisms include the production of carcinogenic metabolites, modulation of the immune response, changes in cell morphology, microbiome alterations, biofilm production, the activation of oncogenic signaling pathways, and the induction of chronic inflammation. These mechanisms may act together or independently to promote cancer development. Although more research is needed to fully grasp the potential role of C. albicans in carcinogenesis, the available evidence suggests that this species may be an active contributor and underscores the importance of considering the impact of the human microbiome on cancer pathogenesis. In this narrative review, we aimed to summarize the current state of evidence and offer some insights into proposed mechanisms.

We study a proper definition of Rényi mutual information (RMI) in quantum field theory as defined via the Petz Rényi relative entropy. Unlike the standard definition, the RMI we compute is a genuine measure of correlations between subsystems, as evidenced by its non-negativity and monotonicity under local operations. Furthermore, the RMI is UV finite and well defined in the continuum limit. We develop a replica path integral approach for the RMI in quantum field theories and evaluate it explicitly in 1+1D conformal field theory using twist fields. We prove that it bounds connected correlation functions and check our results against exact numerics in the massless free fermion theory.

Entanglement entropy is a powerful tool in characterizing universal features in quantum many-body systems. In quantum chaotic Hermitian systems, typical eigenstates have near maximal entanglement with very small fluctuations. Here, we show that for Hamiltonians displaying non-Hermitian many-body quantum chaos, modeled by the Ginibre ensemble, the entanglement entropy of typical eigenstates is greatly suppressed. The entropy does not grow with the Hilbert space dimension for sufficiently large systems, and the fluctuations are of equal order. We derive the novel entanglement spectrum that has infinite support in the complex plane and strong energy dependence. We provide evidence of universality, and similar behavior is found in the non-Hermitian Sachdev-Ye-Kitaev model, indicating the general applicability of the Ginibre ensemble to dissipative many-body quantum chaos.

We study the mixed-state entanglement structure of chaotic quantum many-body systems at late times using the recently developed equilibrium approximation. A rich entanglement phase diagram emerges when we generalize this technique to evaluate the logarithmic negativity for various universality classes of macroscopically thermalized states. Unlike in the infinite-temperature case, when we impose energy constraints at finite temperature, the phase diagrams for the logarithmic negativity and the mutual information become distinct. In particular, we identify a regime where the negativity is extensive but the mutual information is subextensive, indicating a large amount of bound entanglement. When applied to evaporating black holes, these results imply that there is quantum entanglement within the Hawking radiation long before the Page time, although this entanglement may not be distillable into Einstein-Podolsky-Rosen pairs. We claim that at this earlier time, rather than the Page time, information about diaries thrown into the black hole first starts to leak out.

Background: Our objective was to assess the effects of COVID-19 antiepidemic measures and subsequent changes in the function of the health care system on the number of newly diagnosed breast cancers in the Republic of Croatia., Subjects, Materials, and Methods: We performed a retrospective, population- and registry-based study during 2020. The comparator was the number of patients newly diagnosed with breast cancer during 2017, 2018, and 2019. The outcome was the change in number of newly diagnosed breast cancer cases., Results: The average monthly percent change after the initial lockdown measures were introduced was -11.0% (95% confidence interval - 22.0% to 1.5%), resulting in a 24% reduction of the newly diagnosed breast cancer cases in Croatia during April, May, and June compared with the same period of 2019. However, during 2020, only 1% fewer new cases were detected than in 2019, or 6% fewer than what would be expected based on the linear trend during 2017-2019., Conclusion: It seems that national health care system measures for controlling the spread of COVID-19 had a detrimental effect on the number of newly diagnosed breast cancer cases in Croatia during the first lockdown. As it is not plausible to expect an epidemiological change to occur at the same time, this may result in later diagnosis, later initiation of treatment, and less favorable outcomes in the future. However, the effect weakened after the first lockdown and COVID-19 control measures were relaxed, and it has not reoccurred during the second COVID-19 wave. Although the COVID-19 lockdown affected the number of newly diagnosed breast cancers, the oncology health care system has shown resilience and compensated for these effects by the end of 2020., Implications for Practice: It is possible to compensate for the adverse effects of COVID-19 pandemic control measures on breast cancer diagnosis relatively promptly, and it is of crucial importance to do it as soon as possible. Moreover, as shown by this study's results on the number of newly diagnosed breast cancer cases during the second wave of the pandemic, these adverse effects are preventable to a non-negligible extent., (© 2021 AlphaMed Press.)

We study the relative entropy of highly excited quantum states. First, we sample states from the Wishart ensemble and develop a large-N diagrammatic technique for the relative entropy. The solution is exactly expressed in terms of elementary functions. We compare the analytic results to small-N numerics, finding precise agreement. Furthermore, the random matrix theory results accurately match the behavior of chaotic many-body eigenstates, a manifestation of eigenstate thermalization. We apply this formalism to the AdS/CFT correspondence where the relative entropy measures the distinguishability between different black hole microstates. We find that black hole microstates are distinguishable even when the observer has arbitrarily small access to the quantum state, though the distinguishability is nonperturbatively small in Newton's constant. Finally, we interpret these results in the context of the subsystem eigenstate thermalization hypothesis (SETH), concluding that holographic systems obey SETH up to subsystems half the size of the total system.

We present a derivation of the holographic dual of logarithmic negativity in AdS_{3}/CFT_{2} that was recently conjectured in Phys. Rev. D 99, 106014 (2019PRVDAQ2470-001010.1103/PhysRevD.99.106014). This is given by the area of an extremal cosmic brane that terminates on the boundary of the entanglement wedge. The derivation consists of relating the recently introduced Rényi reflected entropy to the logarithmic negativity in holographic conformal field theories. Furthermore, we clarify previously mysterious aspects of negativity at a large central charge seen in conformal blocks and comment on generalizations to generic dimensions, dynamical settings, and quantum corrections.

- Luminal B (HER2 negative) subtype is the most diversiform type of breast cancers, with a high Ki-67 proliferation index (>20%) or/and low progesterone (PR; <20%) with various intensity and distribution of hormone receptors. Considerable difference has also been noticed in disease outcome, wherefore there is the need for a more detailed classification of this tumor subtype. The clinical and pathologic parameters of 147 luminal B (HER2 negative) breast cancers were examined. The expression of hormone receptors in correlation with other prognostic factors and disease outcome was analyzed by Kaplan-Meier curves and multivariate Cox regression analysis. The Kaplan-Mayer analysis showed that low positivity of estrogen (ER) and PR receptors in tumors was associated with a significantly worse disease outcome (overall survival (ER), p=0.020; disease free survival (ER), p=0.019; overall survival (PR), p=0.026; disease free survival (PR), p=0.038)), unlike Ki-67, which did not show a statistically significant connection (overall survival, p=0.343; disease free survival, p=0.322). The intensity of receptor staining and Ki-67 relative to other histopathologic prognostic factors showed a statistically significant correlation solely with histologic grade of tumor. By using the Cox regression model, PR proved to be an independent prognostic factor for overall survival (p=0.004) and disease free survival (p=0.029). The luminal B (HER2 negative) breast cancer with low expression of hormone receptors, independent of the Ki-67 proliferation index, and in correlation with a higher histologic grade, could be a unique subtype of cancer.

High stroma proportion appears to be a very important prognostic factor in esophageal and breast cancer. Previous researches have shown that it might have a similar effect on colorectal cancer. The aim of this study was to determine whether tumor stroma proportion influenced patient survival. This retrospective study included 236 patients with colorectal cancer having undergone surgery in 2006 and 2007 at Osijek University Hospital Center. Location with the highest stroma proportion at the site of deepest tumor invasion was determined. Patients were divided into the groups with high stroma proportion (>50%) and low stroma proportion (≤50%). Stroma proportion showed a statistically significant correlation with tumor stage. Kaplan-Meier survival curves yielded a statistically significant difference in patient overall survival (Cox ph model p=0.016) and progression-free survival (Cox ph model, p=0.0188) according to stroma proportion. Study results showed a statistically significantly shorter overall survival and progression-free survival in patients with high stroma proportion.