Baryonic Popcorn

In the large N limit cold dense nuclear matter must be in a lattice phase. This applies also to holographic models of hadron physics. In a class of such models, like the generalized Sakai-Sugimoto model, baryons take the form of instantons of the effective flavor gauge theory that resides on probe flavor branes. In this paper we study the phase structure of baryonic crystals by analyzing discrete periodic configurations of such instantons. We find that instanton configurations exhibit a series of "popcorn" transitions upon increasing the density. Through these transitions normal (3D) lattices expand into the transverse dimension, eventually becoming a higher dimensional (4D) multi-layer lattice at large densities. We consider 3D lattices of zero size instantons as well as 1D periodic chains of finite size instantons, which serve as toy models of the full holographic systems. In particular, for the finite-size case we determine solutions of the corresponding ADHM equations for both a straight chain and for a 2D zigzag configuration where instantons pop up into the holographic dimension. At low density the system takes the form of an "abelian anti-ferromagnetic" straight periodic chain. Above a critical density there is a second order phase transition into a zigzag structure. An even higher density yields a rich phase space characterized by the formation of multi-layer zigzag structures. The finite size of the lattices in the transverse dimension is a signal of an emerging Fermi sea of quarks. We thus propose that the popcorn transitions indicate the onset of the "quarkyonic" phase of the cold dense nuclear matter.Comment: v3, 80 pages, 18 figures, footnotes 5 and 7 added, version to appear in the JHE

Knowledge, experience and perceptions regarding Molar-Incisor Hypomineralisation (MIH) amongst Australian and Chilean public oral health care practitioners

BACKGROUND: Molar-Incisor Hypomineralisation (MIH) is a prevalent developmental defect of tooth enamel associated with a high burden of disease. The present study aimed to survey Australian and Chilean oral health care practitioners (OHCPs) working in public dental facilities and to compare their knowledge, clinical experience and perceptions about MIH. Findings would give insights about how current knowledge has penetrated into OHCPs working into the public systems. METHODS: A mixed-mode survey regarding MIH was carried out amongst Australian and Chilean OHCPs from the public sector. The survey required responses to questions regarding sociodemographics, clinical experience, perceptions, clinical management and preferences for further training. The level of knowledge regarding MIH was determined by Delphi methods for consensus. Data analysis utilised Chi-square, linear and logistic regression models using SPSS Ver. 22.0. RESULTS: The majority of respondents had observed MIH in their patients (88.6 %) and the level of knowledge regarding MIH was high in Australian participants (p = 0.03). Australian respondents felt more confident when diagnosing (OR 8.80, 95 % CI 2.49-31.16) and treating MIH-affected children (OR 4.56, 95 % CI 2.16-9.76) compared to Chilean respondents. Oral health therapists reported higher levels of confidence than Australian general dental practitioners when providing treatment to children with MIH (OR 7.53; 95 % CI 1.95-29.07). CONCLUSIONS: Continuing to update clinical guidelines may help practitioners increase their understanding when diagnosing and treating MIH-affected children. Dissemination of information and awareness regarding MIH is necessary in public clinics, and in particular Chilean general dental practitioners should be alerted to these factors

Skyrmions, Skyrme stars and black holes with Skyrme hair in five spacetime dimension

We consider a class of generalizations of the Skyrme model to five spacetime dimensions (d = 5), which is de fined in terms of an O (5) sigma model. A special ansatz for the Skyrme field allows angular momentum to be present and equations of motion with a radial dependence only. Using it, we obtain: 1) everywhere regular solutions describing localised energy lumps (Skyrmions); 2) Self-gravitating, asymptotically flat, everywhere non-singular solitonic solutions (Skyrme stars), upon minimally coupling the model to Einstein's gravity; 3) both static and spinning black holes with Skyrme hair, the latter with rotation in two orthogonal planes, with both angular momenta of equal magnitude. In the absence of gravity we present an analytic solution that satisfies a BPS-type bound and explore numerically some of the non-BPS solutions. In the presence of gravity, we contrast the solutions to this model with solutions to a complex scalar field model, namely boson stars and black holes with synchronised hair. Remarkably, even though the two models present key differences, and in particular the Skyrme model allows static hairy black holes, when introducing rotation, the synchronisation condition becomes mandatory, providing further evidence for its generality in obtaining rotating hairy black holes

DNA methylation profiles delineate epigenetic heterogeneity in seminoma and non-seminoma

Background: It remains important to understand the biology and identify biomarkers for less studied cancers like testicular cancer. The purpose of this study was to determine the methylation frequency of several cancer-related genes in different histological types of testicular cancer and normal testis tissues (NT). Methods: DNA was isolated from 43 seminomas (SEs), 14 non-SEs (NSEs) and 23 NT, and was assayed for promoter methylation status of 15 genes by quantitative methylation-specific PCR. The methylation status was evaluated for an association with cancer, and between SEs and NSEs. Results: We found differential methylation pattern in SEs and NSEs. MGMT, VGF, ER-Β and FKBP4 were predominately methylated in NSEs compared with SEs. APC and hMLH1 are shown to be significantly more methylated in both subtypes in comparison with NT. When combining APC, hMLH1, ER-Β and FKBP4, it is possible to identify 86% of the NSEs, whereas only 7% of the SEs. Conclusions: Our results indicate that the methylation profile of cancer-associated genes in testicular cancer correlates with histological types and show cancer-specific pattern for certain genes. Further methylation analysis, in a larger cohort is needed to elucidate their role in testicular cancer development and potential for therapy, early detection and disease monitoring

Biocompatibility and hard tissue-forming ability of CPP-ACP- and CPP- ACFP-modified calcium silicate-based cements

Aims: To evaluate the biocompatibility and osteogenic potential of calcium silicate-based cements (CSCs) modified with casein phosphopeptide – amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide – amorphous calcium fluoride phosphate (CPP-ACFP). Materials and method: Commercially available CSCs were modified with CPP-ACP or CPP-ACFP to prepare CPP-ACP and CPP-ACFP-modified Biodentine™ (0%, 0.5%, 4.0% w/w), Angelus® MTA (0%, 0.5%, 2.0% w/w) and NEX® MTA (0%, 0.5%, 3.0% w/w). For each group, 50 mg, 300 mg and 1500 mg of the cement mixed according to manufacturers’ instructions were placed and adapted at the bottom of 96 well, 24 well and 6 well (respectively) cell culture plates. After 24 h, the cement-coated plates were sterilised by ultraviolet light for 1 h. MG-63, MC3T3-E1, HGF-1, NIH3T3 cells were grown in the cement-coated plates and the cellular proliferation, cellular toxicity, alkaline phosphatase activity, cytokine production (interleukin-1α; IL-1α and interleukin-6; IL-6) and expression of mineralisation-associated proteins (collagen type 1, osteocalcin and osteopontin) were determined. Results: The addition of 0.5% CPP-ACP and 4.0% CPP-ACFP to Biodentine™, and 2.0% CPP-ACFP to Angelus® MTA significantly reduced the proliferation of MG-63. The addition of 4.0% CPP-ACP and 4.0% CPP-ACFP to Biodentine™, 2.0% CPP-ACFP to Angelus® MTA and 3.0% CPP-ACFP to NEX® MTA significantly reduced the proliferation of MC3T3-E1 cells. The tested cements, with and without CPP-ACP and CPP-ACFP, did not induce cellular toxicity nor IL-1α release. The addition of CPP-ACP and CPP-ACFP to Biodentine™ and NEX® MTA, and the addition of CPP-ACP to Angelus® MTA significantly increased the alkaline phosphatase activity of MG-63 cells. The presence of 4.0% CPP-ACP in Biodentine™, 0.5% and 2.0% CPP-ACP in Angelus® MTA, 0.5% CPP-ACFP in Angelus® MTA, and 0.5% CPP-ACFP in NEX® MTA significantly increased the alkaline phosphatase activity of MC3T3-E1 cells. All the tested cements significantly increased the release of IL-6 from MG-63 compared with negative control. The presence of CPP-ACP and CPP-ACFP in NEX® MTA significantly increased the release of IL-6 from MG-63 compared with unmodified NEX® MTA. MC3T3-E1 cells grown on Biodentine™ (unmodified and modified groups) and 3.0% CPP-ACFP-modified NEX® MTA released significantly higher IL-6 compared with negative control. 0.5% CPP-ACFP-modified Biodentine™ and 3.0% CPP-ACFP-modified NEX® MTA induced significantly higher IL-6 release from MC3T3-E1 compared with unmodified Biodentine™ and unmodified NEX® MTA respectively. The tested cements (especially Biodentine™, Angelus® MTA and CPP-ACFP-modified cements) induced the secretion of mineralisation-associated proteins (especially collagen type 1 and osteocalcin).Conclusions: The tested cements are biocompatible, and they could serve as a suitable scaffold which supports cellular proliferation. The addition of CPP-ACP and CPP-ACFP to CSCs improved the cements’ potential to induce osteoblastic differentiation

An International Investigation of Molar Incisor Hypomineralisation (iMIH) and Its Association with Dental Anomalies: Development of a Protocol

Background: Molar incisor hypomineralisation (MIH) is a common disorder of tooth development, which has recently been found to be associated with a higher prevalence of hypodontia. The aim of this international multicentre study is to determine the association between MIH and other developmental anomalies in different populations. Methods: Investigators were trained and calibrated for the assessment of MIH and dental anomalies and ethical approvals obtained in each participating country. The study aimed to recruit 584 children with MIH and 584 children without MIH. Patients aged 7–16 years who attend specialist clinics will be invited to participate. Children will undergo a clinical examination to determine the presence and severity of MIH, using an established index. The presence of any other anomalies, affecting tooth number, morphology, or position, will be documented. Panoramic radiographs will be assessed for dental anomalies and the presence of third permanent molars. Statistical analysis, using a chi squared test and regression analysis, will be performed to determine any differences in dental anomaly prevalence between the MIH and non-MIH group and to determine any association between dental anomalies and patient characteristics. Conclusion: This large-scale study has the potential to improve understanding about MIH with benefits for patient management

Neoadjuvant chemotherapy in breast cancer-response evaluation and prediction of response to treatment using dynamic contrast-enhanced and diffusion-weighted MR imaging

Objective To explore the predictive value of MRI parameters and tumour characteristics before neoadjuvant chemotherapy (NAC) and to compare changes in tumour size and tumour apparent diffusion coefficient (ADC) during treatment, between patients who achieved pathological complete response (pCR) and those who did not. Methods Approval by the Regional Ethics Committee and written informed consent were obtained. Thirty-one patients with invasive breast carcinoma scheduled for NAC were enrolled (mean age, 50.7; range, 37–72). Study design included MRI before treatment (Tp0), after four cycles of NAC (Tp1) and before surgery (Tp2). Data in pCR versus non-pCR groups were compared and cut-off values for pCR prediction were evaluated. Results Before NAC, HER2 overexpression was the single significant predictor of pCR (p=0.006). At Tp1 ADC, tumour size and changes in tumour size were all significantly different in the pCR and non-pCR groups. Using 1.42×10−3 mm2/s as the cut-off value for ADC, pCR was predicted with sensitivity and specificity of 88% and 80%, respectively. Using a cut-off value of 83% for tumour volume reduction, sensitivity and specificity for pCR were 91% and 80%. Conclusion ADC, tumour size and tumour size reduction at Tp1 were strong independent predictors of pCR

Comparative quantification of health risks: Conceptual framework and methodological issues

Reliable and comparable analysis of risks to health is key for preventing disease and injury. Causal attribution of morbidity and mortality to risk factors has traditionally been conducted in the context of methodological traditions of individual risk factors, often in a limited number of settings, restricting comparability. In this paper, we discuss the conceptual and methodological issues for quantifying the population health effects of individual or groups of risk factors in various levels of causality using knowledge from different scientific disciplines. The issues include: comparing the burden of disease due to the observed exposure distribution in a population with the burden from a hypothetical distribution or series of distributions, rather than a single reference level such as non-exposed; considering the multiple stages in the causal network of interactions among risk factor(s) and disease outcome to allow making inferences about some combinations of risk factors for which epidemiological studies have not been conducted, including the joint effects of multiple risk factors; calculating the health loss due to risk factor(s) as a time-indexed "stream" of disease burden due to a time-indexed "stream" of exposure, including consideration of discounting; and the sources of uncertainty