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Mold fluxes play an important role in the lubrication and heat transfer control between the mold wall and steel shell during the continuous casting process. To ensure control of the heat transfer, it is necessary to evaluate the crystallinity of mold flux. The casting of peritectic steel commonly uses the mold flux that forms crystalline phases. These phases, in particular the cuspidine (Ca4Si2O7F2), increase resistance to radiation heat transfer, leading the steel to cool slowly and to ensure the production of defect-free products. The purpose of this paper is to create alternative peritectic fluxes obtaining gain due to the use of a cheaper raw material, avoiding the disposition of residues in the environment. Thus, using FactSage® software, new mold fluxes were simulated from a commercial peritectic flux with additions of calcific marble residue, SiO2 and CaF2. From the thermodynamics simulations, three new fluxes were chosen and experimentally developed. In those fluxes, the physical properties such as melting point, break temperature, phases and microstructure were analyzed and compared with the commercial peritectic flux. The measurements using Differential Thermal Analysis (DTA) showed that there was no significant change in the melting point and break temperature. Cuspidine, crystalline phases and dolomite were established in all new samples. By using the thin-film technique, it was possible to observe that the microstructures of the new fluxes obtained were similar to with the commercial one. The presence of acicular grains was the main difference in the sample with highest residue concentration. Keywords: Peritectic mold flux, Calcitic marble, Physical properties, Acicular grains

Rhinoscleroma is a chronic, infectious and granulomatous disease of the respiratory tract. There is often a delay in diagnosis due to unfamiliarity with the disease and also because culture is not always positive. We report a case in a 26-year-old woman with granular mass obstructing bilateral nasal cavities and causing breathing difficulty. Histopathological examination showed characteristic Mikulicz histiocytes containing numerous Gram-negative intracellular rod-shaped bacilli consistent with the diagnosis of rhinoscleroma. The patient was treated with gemifloxacin and tetracycline and remains asymptomatic over a year follow-up period. It is important to consider rhinoscleroma in cases of chronic nasal obstruction. As culture is not always positive, histopathological examination may be crucial to the diagnosis. Keywords: rhinoscleroma, nasal obstruction, histopathology

A 12-year-old female patient started with sudden abdominal pain, polyuria, polydipsia, anorexia and a drop in cons-cience level. She was diagnosed with untreated type I diabetes mellitus (diabetic acidosis), with blood sugar of 508 mg/dl upon hospital admission. After one week in the hospital, she started having eyelid ptosis, facial pain, converging strabismus, left side epistaxis and a progressive wor-sening of her general health.Skull and paranasal sinuses CT scan and MRI showed a soft tissue mass in the left nasal cavity, invading the ethmoidal, maxillary and cavernous sinuses and the ipsilateral orbit (Figure 1).An endoscopic-guided tumor biop-sy showed mucormycosis. The patient was started in high doses of endovenous am-phothericin B liposome for 45 days. There was a mild improvement only. Anterior rhinoscopy showed a large brown-greenish mass occupying the entire left nasal cavity.We decided to do a nasosinusal endoscopic exploration. During the proce-dure we noticed a large mass coming from the maxillary sinus and the left nasal cavity. We did an exhaustive surgical debridement and cleaning in the maxillary, ethmoidal and sphenoidal sinuses with hypertonic saline solution, and we also flushed the region with an amphothericin B solution. Histology revealed a zygomycosis by Mu-cor genus fungi.The patient had a favorable outco-me and returned in one week for a review. Upon anterior rhinoscopy, we noticed a fungal mass. A new CT scan suggested tumor recurrence. The patient was then submitted to 29 daily sessions of oxygen therapy in a hyperbaric chamber and the amphothericin B was exchanged for intra-venous itraconazole because of the long term use of the former, and she was also submitted to a rigorous diabetic control.There was a mild improvement and stability on her condition, leading us to choose to do a second look endoscopic exploration. The left nasal cavity was broad and clear, without any evidence of infec-tion. The maxillary sinus ostium was open and there were no signs of mucormycosis.The patient was discharged from the hospital in a stable condition and using oral itraconazole. The endoscopic view confirmed disease clearance. She is currently asymptomatic. Her capillary glucose is strictly controlled. She has nerve palsy of the III and IV cranial nerves on the left, however with good visual acuity and no diplopia.