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J. Cogdell, J. Jorgenson, L. Smajlović

In Cogdell et al., LMS Lecture Notes Series 459, 393–427 (2020), the authors proved an analogue of Kronecker’s limit formula associated to any divisorD which is smooth in codimension one on any smooth Kähler manifold X . In the present article, we apply the aforementioned Kronecker limit formula in the case when X is complex projective space CP for n ≥ 2 and D is a hyperplane, meaning the divisor of a linear form PD(z) for z = (Zj) ∈ CP. Our main result is an explicit evaluation of the Mahler measure of PD as a convergent series whose each term is given in terms of rational numbers, multinomial coefficients, and the L-norm of the vector of coefficients of PD.

A. Crnogorac, S. Panno, A. Mandić, Mladen Gašpar, A. Caruso, E. Noris, S. Davino, S. Matić

The sanitary status of grapevines has not yet been considered sufficiently in vineyards throughout Bosnia and Herzegovina (BiH). An extensive survey of five major grapevine viruses in the country was carried out in 2019. A total of 630 samples from the two dominant autochthonous cultivars, named Žilavka and Blatina, were tested by DAS-ELISA for the presence of grapevine leafroll-associated viruses (GLRaV-1 and 3), grapevine fleck virus (GFkV), grapevine fanleaf virus (GFLV) and Arabis mosaic virus (ArMV). Eighty-eight % of the samples were positive for at least one virus, and all five viruses were detected, thought with different incidence, i.e. GLRaV-3 (84%), GFLV (43%), GLRaV-1 (14%), GFkV (10%) and ArMV (0.2%). The majority of infected plants (about 75%) were asymptomatic. Specific virus symptoms were observed in the remaining infected plants, together with the reported GLRaV vectors, Planococcus ficus and Parthenolecanium corni, while nematodes of the Xiphinema genus were not found in the GFLV- or ArMV-infected vineyards. The GLRaV-3 CP phylogenetic analyses showed 75–100% nucleotide identity between the BiH and reference isolates, and the BiH isolates clustered into the major group. The dNS/dS ratio indicated a negative selection of the virus population, and the lack of geographical structuring within the population was observed. In addition, putative GLRaV-3 recombinants with breakpoints in the 5’ of the CP gene were detected, while no recombinant strains were identified for the other four viruses. The obtained results indicate a deteriorated sanitary status of the cultivated grapevines, the prevalence and intraspecies genetic diversity of GLRaV-3 throughout the country. The establishment of certified grapevine material and adequate virus vector control is therefore of primary importance to prevent further spread of these viruses. This study presents the results of the first molecular characterisation of grapevine viruses in Bosnia and Herzegovina.

G. Tomson, S. Causevic, O. Ottersen, S. Swartling Peterson, S. Rashid, R. Wanyenze, A. Yamin

Göran Tomson and colleagues argue that our ability to control pandemics requires global action to counter inequalities from demographic, environmental, technological, and other megatrends

Introduction: Tumor microenvironment plays a significant role in tumor progression. Tumor stroma is one of the strongest modifiers of tumor cell response, cancer behavior, and cancer progression. This study aimed to investigate the correlation of matrix metalloproteinase-9 (MMP-9) expression and tumor-stroma ratio (TSR) with standard clinicopathological parameters in different molecular subtypes of breast cancer.Methods: Ninety biopsy samples of primary breast cancer diagnosed at the Department of Pathology, School of Medicine, Sarajevo, were selected for this study. The molecular subtype was determined based on the immunohistochemical expression of estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, and Ki-67. Stromal and tumoral MMP-9 immunohistochemical expression and the TSR were determined for each tumor.Results: Tumoral MMP-9 expression correlated positively with the presence of lymphovascular invasion (p= 0.016). TSR showed significant association and correlation with tumor grade (G) (p= 0.031; p= 0.049) and tumor size (pT) (p = 0.049;p= 0.021, respectively). Stromal MMP-9 expression correlated with histologic type, histologic grade of tumor, and lymphocytic inflammatory infiltrate (p= 0.021;p= 0.047, p= 0.038, respectively). A higher percentage of stromal MMP-9 expression correlated with the strongest lymphocytic response (p = 0.007). Significant correlation was observed between molecular subtypes and histologic grade of the tumor (p= 0.032).Conclusion: Our results, to some extent, confirm the significance of the tumor microenvironment in breast cancer, especially when it is about stromal MMP-9 expression. Although we observed significant association, without linear correlation, we found no significant correlation between molecular subtypes of breast cancer and MMP-9 expression.

Jasmina Okičić, Meldina Kokorović Jukan, M. Herić

The purpose of this research is to provide some insights into financial literacy among undergraduate students focusing primarily on the relationship between financial knowledge, financial attitudes and financial behavior and on possible gender and financial education gap in financial literacy. Using the purposive sampling technique, data collection was carried out from April to June 2020, yielding a sample of 1,046 valid responses. To gain a better understanding of the relationship between financial behaviour, financial attitudes and financial knowledge, we, primarily, use exploratory factor analysis and multiple regression model. The research findings have revealed several important issues. First, findings have suggested that financial knowledge, financial attitudes and gender may be considered as an antecedent of the financial behaviour of undergraduate students. Second, findings have also suggested a statistically - significant difference between the financial literacy of undergraduate students concerning their exposure to formal financial education.

J. Mulec, Andreea Oarga-Mulec, L. Holko, L. Pasic, A. Kopitar, T. Eleršek, A. Mihevc

Paradana is one of the biggest ice caves in Slovenia, with an estimated ice volume of 8,000 m3. Reflecting climatological conditions, the cave ice undergoes repeated freeze-thaw cycles and regular yearly deposition of fresh ice. Three distinct ice block samples, collected from the frozen lake in May 2016, were analysed to obtain data on ice physicochemical properties and the composition of associated microbiota. Isotopic composition of the ice samples (18O, 2H) and a local meteoric water line (LMWL) constructed for monthly precipitation at Postojna were used to estimate the isotopic composition of the water that formed the ice, which had high values of deuterium excess and low concentrations of chloride, sulphate and nitrate. The values of total organic carbon (1.93–3.95 mg/l) within the ice blocks fall within the range of those measured in karst streams. Total cell count in the ice was high and the proportion of cell viability increased along the depth gradient and ranged from 4.67 × 104 to 1.52 × 105 cells/ml and from 51.0 to 85.4%, respectively. Proteobacteria represented the core of the cave-ice microbiome (55.9–79.1%), and probably play an essential role in this ecosystem. Actinobacteria was the second most abundant phylum (12.0–31.4%), followed in abundance by Bacteroidetes (2.8–4.3%). Ice phylotypes recorded amounted to 442 genera, but only 43 genera had abundances greater than 0.5%. Most abundant were Pseudomonas, a well-known ice dweller, and Lysobacter, which previously was not reported in this context. Finally, two xanthophytes, Chloridella glacialis and Ellipsoidion perminimum, known from polar environments, were cultured from the ice. This indicates that the abundance and ecological role of phototrophs in such environments might be greater than previously deduced.

A. Macken, A. Prkić, K. Koenraadt, I. van Oost, A. Spekenbrink-Spooren, B. The, D. Eygendaal

Background This study aims to use the Dutch Arthroplasty Register data to report an overview of the contemporary indications and implant designs, and report the short-term survival of radial head arthroplasty. Methods From the Dutch Arthroplasty Register, data on patient demographics, surgery and revision were extracted for radial head arthroplasties performed from January 2014 to December 2019. Implant survival was calculated using the Kaplan–Meier method. Results Two hundred fifty-eight arthroplasties were included with a median follow-up of 2.2 years. The most common indication was a fracture of the radial head (178, 69%). One hundred thirty-nine (68%) of the prostheses were of bipolar design, and the most commonly used implant type was the Radial Head System (Tornier; 134, 51%). Of the 258 included radial head arthroplasties, 16 were revised at a median of six months after surgery. Reason for revision was predominantly aseptic loosening (9). The overall implant survival was 95.8% after one year, 90.5% after three years and 89.5% after five years. Discussion For radial head arthroplasties, acute trauma is the most common indication and Radial Head System the most commonly used implant. The implant survival is 89.5% after five years.

C. Deischinger, Elma Dervić, Michaela Kaleta, Peter Klimek, A. Kautzky-Willer

Background: In general, the risk to develop Parkinson’s disease (PD) is higher in men compared to women. Besides male sex and genetics, research suggests diabetes mellitus (DM) is a risk factor for PD as well. Objective: In this population-level study, we aimed at investigating the sex-specific impact of DM on the risk of developing PD. Methods: Medical claims data were analyzed in a cross-sectional study in the Austrian population between 1997 and 2014. In the age group of 40–79 and 80+, 235,268 patients (46.6%females, 53.4%males) with DM were extracted and compared to 1,938,173 non-diabetic controls (51.9%females, 48.1%males) in terms of risk of developing PD. Results: Men with DM had a 1.46 times increased odds ratio (OR) to be diagnosed with PD compared to non-diabetic men (95%CI 1.38–1.54, p < 0.001). The association of DM with newly diagnosed PD was significantly greater in women (OR = 1.71, 95%CI 1.60–1.82, p < 0.001) resulting in a relative risk increase of 1.17 (95%CI 1.11–1.30) in the age group 40 to 79 years. In 80+-year-olds the relative risk increase is 1.09 (95%CI 1.01–1.18). Conclusion: Although men are more prone to develop PD, women see a higher risk increase in PD than men amongst DM patients.

O. Ibrahimagić, A. Vujadinović, Z. Ercegović, S. Kunić, D. Smajlović, Z. Dostović

Dear Co-editors-in-Chief Kanis and Cosman, We have read with great attention the article “Osteoporosis in the age COVID-19 patients”, written by Girgis and CliftonBligh (authors) in the July issue of Osteoporosis International. We welcome the opportunity to make a short comment as well. This very interesting article evaluates treatment of osteoporosis in disaster of COVID-19. The authors emphasized that osteoporosis kills and every year almost, 750,000 people lose their lives around the world as a result of hip fracture [1]. We want to highlight that older patients (very often with osteoporosis) are also with increased risk for mortality due to novelty SARS-CoV-2 pandemic. Evidence of osteoporosis associating nutritional factors; particularly calcium and vitamin D are reviewed as association of falls risk with fracture [2]. Unfortunately, in the group of very old patients with fragility fractures, only 28.6% were on adequate osteoporosis treatment [3]. High serum homocysteine has been shown to have detrimental effects on neural cells, vascular endothelial cells, osteoblasts, and osteoclasts. Therefore, hyperhomocysteinemiamay be regarded as a factor that can reduce both bone mass and impair bone quality [4]. In addition, high serum homocysteine often associated increased risk for fractures. Unfortunately, hyperhomocysteinemia appeared to be predictive of all-cause mortality, independent of frailty, an age-related clinical state characterized by a global impairment of physiological functions and involving multiple organ systems [5]. Values of vitamin B9 (folic acid) and B12 are in negative correlation with levels of homocysteine [6]. Furthermore, according to PubMed survey, there was no reliable data due to concomitance of COVID-19, hyperhomocysteinemia, and osteoporosis/fractures. So, what to do when we have older COVID-19 patient with hyperhomocysteinemia and high risk for bone fracture? Authors highlighted: “Clinicians need to adapt to the challenges posed by this crisis and consider ways to continue serving the most vulnerable amongst us, those with chronic disease with their own substantive morbidity and mortality”. In light of this, we suggest that level of homocysteine and B9/B12 vitamin should be measured at clinical follow-up in all older patients with COVID-19, immediately after hospitalization. If persistent, hyperhomocysteinemic proosteoporotic (but also prothrombotic) state should be promptly decreased in acute phase of COVID-19, on the base of Latin phrase primum non nocere. Our studies from Bosnia and Herzegovina showed that the intake of B9 vitamin, sometimes with B12 vitamin as well, was efficient in creating normalized homocysteine levels in older patients with ischemic stroke and Parkinson’s disease [7, 8]. Fortunately, risk of side effects is minimal if the daily dose of B9 vitamin is 1–5 mg [9]. So, we point out that B9/B12 vitamin are “on the first-line”—good and safe in reduction levels of homocysteine in various older patients. In addition, B2/B3/B6 vitamins are enhancers of the immune system and might be efficient as soldiers from second echelon in battling with COVID-19 [10]. All in all, B-vitamins can, ad hoc, become the medication of choice in the treatment when unhidden hyperhomocysteinemia/osteoporosis coexists with COVID-19. Lastly, we emphasize that further studies will elucidate proosteoporotic/prothrombotic potential of hyperhomocysteinemia in COVID-19 patients as well as beneficial add-on effects of B-vitamins. * S. Kunić suljo.kunic@hotmail.com

M. D. Buck, Enzo Z. Poirier, A. Cardoso, Bruno Frederico, Johnathan Canton, S. Barrell, R. Beale, R. Byrne et al.

The ongoing pandemic of SARS-CoV-2 calls for rapid and cost-effective methods to accurately identify infected individuals. The vast majority of patient samples is assessed for viral RNA presence by RT-qPCR. Our biomedical research institute, in collaboration between partner hospitals and an accredited clinical diagnostic laboratory, established a diagnostic testing pipeline that has reported on more than 252,000 RT-qPCR results since its commencement at the beginning of April 2020. However, due to ongoing demand and competition for critical resources, alternative testing strategies were sought. In this work, we present a clinically-validated procedure for high-throughput SARS-CoV-2 detection by RT-LAMP that is robust, reliable, repeatable, specific, and inexpensive.

Sabrina E. Wang, A. Hodge, S. G. Dashti, S. Dixon-Suen, H. Mitchell, R. Thomas, E. Williamson, E. Makalic et al.

Abstract Objective: To examine associations between diet and risk of developing gastro-oesophageal reflux disease (GERD). Design: Prospective cohort with a median follow-up of 15·8 years. Baseline diet was measured using a FFQ. GERD was defined as self-reported current or history of daily heartburn or acid regurgitation beginning at least 2 years after baseline. Sex-specific logistic regressions were performed to estimate OR for GERD associated with diet quality scores and intakes of nutrients, food groups and individual foods and beverages. The effect of substituting saturated fat for monounsaturated or polyunsaturated fat on GERD risk was examined. Setting: Melbourne, Australia. Participants: A cohort of 20 926 participants (62 % women) aged 40–59 years at recruitment between 1990 and 1994. Results: For men, total fat intake was associated with increased risk of GERD (OR 1·05 per 5 g/d; 95 % CI 1·01, 1·09; P = 0·016), whereas total carbohydrate (OR 0·89 per 30 g/d; 95 % CI 0·82, 0·98; P = 0·010) and starch intakes (OR 0·84 per 30 g/d; 95 % CI 0·75, 0·94; P = 0·005) were associated with reduced risk. Nutrients were not associated with risk for women. For both sexes, substituting saturated fat for polyunsaturated or monounsaturated fat did not change risk. For both sexes, fish, chicken, cruciferous vegetables and carbonated beverages were associated with increased risk, whereas total fruit and citrus were associated with reduced risk. No association was observed with diet quality scores. Conclusions: Diet is a possible risk factor for GERD, but food considered as triggers of GERD symptoms might not necessarily contribute to disease development. Potential differential associations for men and women warrant further investigation.

B. Het'enyi, Yetkin Pulcu, S. Dogan

We address the question of different representation of Bloch states for lattices with a basis, with a focus on topological systems. The representations differ in the relative phase of the Wannier functions corresponding to the diffferent basis members. We show that the phase can be chosen in such a way that the Wannier functions for the different sites in the basis both become eigenstates of the position operator in a particular band. A key step in showing this is the extension of the Brillouin zone. When the distance between sites within a unit cell is a rational number, $p/q$, the Brillouin extends by a factor of $q$. For irrational numbers, the Brillouin zone extends to infinity. In the case of rational distance, $p/q$, the Berry phase"lives"on a cyclic curve in the parameter space of the Hamiltonian, on the Brillouin zone extended by a factor of $q$. For irrational distances the most stable way to calculate the polarization is to approximate the distance as a rational sequence, and use the formulas derived here for rational numbers. The use of different bases are related to unitary transformations of the Hamiltonian, as such, the phase diagrams of topological systems are not altered, but each phase can acquire different topological characteristics when the basis is changed. In the example we use, an extended Su-Schrieffer-Heeger model, the use of the diagonal basis leads to toroidal knots in the Hamiltonian space, whose winding numbers give the polarization.

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