Firms’ Price Markups and Returns to Scale in Imperfect Markets: Bulgaria and Hungary

Under perfect competition and constant returns to scale, firms producing homogeneous products set their prices at their marginal costs which also equal their average costs. However, the departure from these standard assumptions has important implications with respects to the derived theoretical results and the validity of the related empirical analysis. In particular, monopolistic firms will charge a markup over their marginal costs. We show that firms’ markups tend to be directly associated with the employed production technology, more specifically with their returns to scale. Accordingly, we analyze the implications for the markup ratios from the incidence of non-constant returns to scale. We present quantitative results illustrating the effect of the returns to scale index on the firms’ price markups, as well as the relationship between the two indicators, on the basis of firm-level data for Bulgarian and Hungarian manufacturing firms.http://deepblue.lib.umich.edu/bitstream/2027.42/40096/3/wp710.pd

Hüvelyi hálóműtétek gyakorlata az amerikai korlátozó figyelmeztetés után : merjem vagy ne merjem

Introduction: The prevalence of pelvic organ prolapse (POP) with aging is escalating alarmingly, and now becoming a growing epidemic among the elderly. Synthetic transvaginal mesh (TVM) has been employed with increasing popularity in the treatment of POP until the end of the last decade. After the U.S. Drug and Food Administration (FDA) warnings in the years 2008 and 2011, the number of vaginal mesh operations has decreased dramatically.Aim: The aim of the study was to evaluate and compare the anti-POP effectivity, the anti-stress incontinence (anti- SUI) efficacy, and the late (36 months) post-operative complications of the anterior vaginoplasty and the TVM operations. Method: We analysed the clinical data from 120 patients with stage II–III anterior prolapse and concomitant SUI who had undergone surgery at a tertiary referral centre in Hungary between January 2013 and January 2014. Sixty patients underwent Kelly–Stoeckel vaginoplasty and the other 60 cases had TVM operation. The surgical complications were classified using the Clavien–Dindo (CD) classification system. Results: The anti-POP (91.6% vs. 63.3%; p<0.001) and the anti-SUI efficacy (90% vs. 55%, p<0.001) were significantly higher in the TVM group than in the vaginoplasty group, while the overall extrusion rate was found 8.3% after a 3-year follow-up. The Clavien–Dindo score (CD) proved that the early post-operative complication profile was similar among the TVM patients as compared to the vaginoplasty group (p = 0.405). Conclusions: Vaginal mesh surgery represents an effective procedure for prolapse and concomitant SUI with a decreased risk of short- and long-term complications

Nanostructured titanium dioxide as an antimicrobial agent on grapevine (Vitis Vinifera L.) leaves: a phytotoxicological study

In the past two decades, nanostructured materials including colloidal nanocrystals, semiconductor nanoparticles, nanotubes, nanowires and porous materials have received a great attention thanks to their unique physicochemical properties. Titanium dioxide nanoparticles (TiO2 NPs) excited by UV light can produce different reactive oxygen species (ROS) such as hydroxyl radical, superoxide radical anion and singlet oxygen. This special feature of TiO2 NPs so-called photocatalytic property can be exploited in numerous fields, especially in water treatment technologies for removing toxic compounds or inactivation various pathogens. In this work we applied directly TiO2 NPs on the grapevine (Vitis vinifera cv. Cabernet sauvignon) leaves as potential antimicrobial agent. Experiments were performed under field conditions where the plants were exposed to sunlight. Physiological responses, flavonol profile and micro- macroelements of the leaves were studied. We found that TiO2 NPs with the concentration of 250 3 00 mg kg-1 increased the stomatal conductance whereas decreased the photosynthetic rate. Despite of their negative effect on photosynthesis, flavonol profile as a stress sensitive factor showed only minor changes after the foliar exposure as revealed by HPLC-DAD measurements. Elevated level of K, Mg, Ca, P and B were detected in the treated leaves which may be related to the increased stomatal opening. Our results indicate that TiO2 NPs with the applied concentration can be phytotoxic in the presence of UV irradiation which probably stem from the excess of ROS production of nanoparticles. Consequently, further studies are necessary for determining the parameters which allows safety and efficient field applications of TiO2 NPs

Post-harvest UV-B treatment of White Sultanina grapevine berries

The grapevine berries are an important source of phenolic compounds. In this study, White Sultanina berries were treated with UV radiation and followed quantitative change of these secondary metabolites. In the skin of cv. White Sultanina table grapes, a phenolic acid and several mono-glycosilated flavonols were identified by HPLC-DAD. The aim of this work was to alter this profile, to improve antioxidant properties. Resveratrol contents of berry skins have already been successfully increased using UV-C or UV-B radiation (Cantos et al. 2000) in another variety (cv. Napoleon). In this study, we report a UV-B-inducible increase in flavonoid-glycosides observed 2 h after 30 min exposure to 11.5 W/m2 radiation flux (physical dose) from a narrow band source (VL-215M centred at 312 nm, Vilbert Lourmat, France). This was accompanied by higher antioxidant capacities of berry skin extracts, in accordance with the observed strong antioxidant capacities of quercetin-glycosides in vitro (Csepregi et al. 2016, Csepregi and Hideg 2018). Differences between UV-B-treated berries and untreated controls were less pronounced when assayed after a longer storage period following irradiation at 20 ℃ under low fluxes (60 µmol m-2s-1) of photosynthetically active radiation. Berry skin photosynthesis, measured as photochemical yield using imaging PAM (Heinz Walz GmbH, Effeltrich, Germany) temporary increased after the UV-B treatment, then declined, suggesting a possible metabolic source of increased flavonol biosynthesis. These experiments suggest that UV-B irradiation of table grapes can be beneficial in terms of increasing the content of potentially health-promoting flavonol derivatives