INFLUENCES OF GRINDING CONDITIONS ON GALENITE-SPHALERITE FLOTATION KINETICS

Grinding is more than just crushing, it is also a process that causes a chemical reaction on the surface of the mineral. Water used in the grinding process significantly affects the galvanic interaction. Different grinding conditions result in different pulp chemistries. This becomes especially important in sulfide flotation in terms of recovery and selectivity. There are limited studies examining the effects of dry and wet grinding prior to the flotation of sulfide minerals. This study compared the effects of wet and dry grinding on the flotation kinetics of complex Pb-Zn sulfide ore at P80 of 20 and 50 µm grind sizes. Results showed that dry grinding positively affected the sphalerite ore flotation compared to wet grinding in terms of recovery and grade in both galenite and sphalerite rougher flotation stages. Considering that the effect of dry grinding was due to the difference in pulp chemistry, the reasons were explored based on particle morphology, and pulp potentials. The results showed that grinding the same ore under dry and wet conditions significantly affected the flotation performance. In light of the pulp potential measurements, it was determined that the reducing environment obtained in the wet grinding negatively affected the flotation performance, while the oxidizing environment formed during the dry grinding affected the flotation performance positively. This was attributed to the fact that galvanic interactions that occurred during wet grinding were significantly reduced during dry grinding. Hence, better galenite and sphalerite flotation was obtained following dry grinding

SODIUM DITHIONITE AS A PYRITE DEPRESSANT IN GOLD ORE FLOTATION

Sodium dithionite (Na2S2O4) is a widely used reducing agent to control pulp potential (Eh) and pyrite depressant in sulfide ore flotation. In this study, the pyrite depressant effect of sodium dithionite on gold ore flotation was investigated at pH 8 and pH 10.5 comparatively in terms of gold, chalcopyrite, and pyrite recoveries and grades. The presence of sodium dithionite resulted in a drop of approximately 50–70 mV in the Eh values, regardless of the studied pH values, confirming the reducing effect of sodium dithionite. The effects of sodium dithionite on gold and chalcopyrite grades and recoveries were quite limited, especially at pH 10.5. At pH 8, the utilization of sodium dithionite slightly decreased gold and chalcopyrite recovery and grades, while the decrease in pyrite recovery and grades was remarkable. Both pyrite recovery and grade were reduced from 79.5% to 54.7% and 15.3% to 10.7% by the utilization of sodium dithionite at pH 8. In conclusion, it is considered that the selective flotation of gold and chalcopyrite from pyrite can be achieved at a lower pH accompanied by a slightly reduced Eh by the utilization of sodium dithionite

Forgotten and fragmented ureteral j stent with stone formation: combined endoscopic management

ABSTRACTObjective : Ureteral stents are widely used in endo-urological procedures. However, ureteral stents can be forgotten and cause serious complications, including fragmentation, migration and urosepsis.There are few reports about forgotten and fragmented ureteral stents with stone formation. We aimed to present this rare case with successful combined endo-urological management.</p

Utility of 'dual phase' cone beam computed tomography during radioembolisation in patients with hepatocellular carcinoma : what is really changing in flow dynamics before and after 90Y delivery?

Purpose: The aims of the study were: 1) to compare two phases of dual-phase cone beam computed tomography (DPCBCT) achieved before and after Yttrium-90 (90Y) administration and to evaluate additional benefits during radioembolisation (RE) procedures; and 2) to compare DP-CBCT with pre-procedure contrast enhanced cross-sectional images in terms of tumour detection. Material and methods: Twenty-three hepatocellular carcinoma patients undergoing RE treatment were scanned with DPCBCT consisting of early arterial (EA) and late arterial (LA) phases before and after 90Y administration. The CT-like datasets were compared according to embolisation effect, enhancement patterns, lesion detectability, image quality, and artifacts by two interventional radiologists blinded to each other. The compatibility of the two radiologists was evaluated with kappa statistical analysis, and the difference between EA and LA phases was evaluated with marginal homogeneity test. Also, DP-CBCT images were compared with preprocedural cross-sectional images (CT/MRI). Results: For 23 patients 92 data were acquired. Thirteen patients showed a decrease on post-embolisation images both visually and on Hounsfield unit (HU) measurements. No statistical difference was found for tumour detection between EA and LA phases (p = 1.0). Tumour enhancement was visually superior at LA phases whereas EA phases were better for arterial mapping for selective catheterisation. DP-CBCT images were not inferior to preprocedural cross-sectional imaging findings. Conclusions: DP-CBCT is a promising tool for predicting tumour response to therapy and is not inferior to preprocedural cross-sectional imaging in terms of tumour detection. It allows better assessment during RE procedures because early phases provide good mapping for superselective catheterisation whereas late phases are better for visualisation of tumour enhancement

Evaluation of oxidative stress in degenerative rotator cuff tears

Background: Oxidative stress occurs as a result of the disruption of the balance between the formations of reactive oxygen species and antioxidant defense mechanisms during the conversion of nutrients into energy. Increased body oxidative stress has been reported to be involved in the etiology of several degenerative and chronic diseases. We hypothesized that the body oxidative stress level is higher in patients with atraumatic degenerative rotator cuff tear than that in healthy individuals. Methods: The patients who underwent arthroscopic repair for atraumatic, degenerative rotator cuff tear were prospectively evaluated. A total of 30 patients (group 1, 19 females and 11 males; mean age: 57.33 ± 6.96 years; range: 50-77 years) and 30 healthy individuals (group 2, 18 females and 12 males; mean age: 56.77 ± 6 years; range: 51-72 years) were included in the study. The Constant and American Shoulder and Elbow Surgeons scoring systems were used to evaluate the clinical outcomes. Serum oxidative stress parameters of the patients and the control group were biochemically evaluated. Accordingly, thiol/disulfide (DS) balance (DS/native thiol [NT], DS/total thiol [TT]), Total Oxidant Status (TOS), oxidative stress index, and nuclear factor erythroid-2–associated factor-2 values were used as the biochemical parameters indicating an increase in the serum oxidative stress level. Total antioxidant status and NT/TT values served as the biochemical parameters indicating a decrease in the serum oxidative stress level. Results: The study follow-up duration was 12 months. A statistically significant increase was observed in American Shoulder and Elbow Surgeons and Constant scores of patients who underwent arthroscopic rotator cuff repair relative to that during the preoperative period (P = .01). The values of biochemical parameters (DS/NT, DS/TT, TOS, oxidative stress index, and nuclear factor erythroid-2–associated factor-2), which indicated an increase in the serum oxidative stress, were significantly higher in preoperative patients than those in postoperative patients, albeit the control group values were significantly lower than those of the postoperative patients. The biochemical parameters (NT/TT and total antioxidant status) indicating a decrease in the serum oxidative stress levels were significantly higher in the postoperative patients than those in the preoperative patients and significantly lower than those in the control group. Conclusion: High levels of markers indicating an increase in the serum oxidative stress in patients with degenerative rotator cuff rupture suggested that TOS may be involved in the etiopathogenesis of rotator cuff degeneration. Although the oxidative load decreases during the postoperative period, the fact that it is still higher than that in healthy individuals supports this claim. © 2022 Journal of Shoulder and Elbow Surgery Board of Trustee

Kulaklı orman baykuşunda (Asio Otus) dispharynx nasuta (Rudolphi, 1819) olgusu

Milli Parklar görevlilerince Afyon Kocatepe Üniversitesi Veteriner Sağlık Uygulama ve Araştırma Merkezine getirilen kulaklı orman baykuşunda klinik olarak kaşekşi ve dehidrasyon tespit edilmiş ve ani ölüm gerçekleşmiştir. Nekropsi sonucunda ingluvitis, proventriculitis, esophagitis ve bu organlarda parazitlere rastlanmıştır. Bunun yanında baykuşta, orta şiddette purulent bronkopnömoni, akciğerlerde geniş kanamalar, tüm doku ve organlarda şiddetli hiperemi tespit edilmiştir. Parazitoloji laboratuvarına gönderilen 1 tane parazitin incelenmesi neticesinde Dispharynx nasuta olduğu teşhis edilmiştir. Bu olgu Türkiye'de baykuşlarda ilk bildirim olmuştur.Cachexia and dehydration were detected as the clinical sign and sudden death occurred in a long-eared owl which was brought to Veterinary Health Practice and Research Center of Afyon Kocatepe University by officers of National Parks. As a result of necropsy, ingluvitis, proventriculitis, esophagitis and the parasites were detected throughout these organs. Furthermore, mild purulent bronchopneumonia, wide hemorrhages in lungs, severe hyperaemia among all tissues and organs were detected in the long-eared owl. After examination of one parasite which was sent to parasitology laboratory, it was diagnosed as Dispharynx nasuta. This case is the first report of Dispharynx nasuta from an owl in Turkey

Comparison of Efficacy and Complications of Holmium Laser and Pneumatic Lithotripters Used in the Ureterorenoscopic Treatment of Proximal Ureter Stones, a Multi-Center Study of Society of Urological Surgery Aegean Study Group

Objective:The aim of this study is to compare the efficacy and complications of holmium laser and pneumatic lithotripsy used in the ureterorenoscopic treatment of proximal ureteral stones.Materials and Methods:Data of 638 patients, who underwent ureterorenoscopy (URS) due to proximal ureteral stones in different centers, were obtained from patient files. The patients were divided into two groups according to the type of lithotripter used: group 1; laser lithotripter (n=324; 50.8%) and group 2; pneumatic lithotripter (n=314; 49.2%). URS was considered successful upon determination stone-free status with the imaging methods after treatment. The effectiveness and the complications of holmium:yttrium-aluminum-garnet laser and pneumatic lithotripsy were compared.Results:The total success rate of URS was 82.6% and the complication rate was 8.1%. The mean age of patients was similar between the groups; however, the body mass index values, stone surface area and stone Hounsfield unit were significantly higher in group 1. Although the mean operative time, complication rate and the mean length of hospital stay were similar between the groups; the URS success and postoperative ureteral J stent use rates were significantly higher in group 1 and the push-back rate was significantly higher in group 2.Conclusion:If laser lithotripsy is available in a clinic, we believe that it is better to use it as the first option in the treatment of proximal ureter stones. However, considering that it is not easy to access laser lithotripters due to their high cost in Turkey, pneumatic lithotripters may be an effective and inexpensive alternative that can also be safely used in these cases

Effect of the Anesthetic Method on the Outcomes of Ureteroscopy for Proximal Ureteral Stones: A Multi-center Study of the Society of Urological Surgery Aegean Study Group

Objective:To analyze the effect of the anesthesia method (spinal and general) on the outcome of ureteroscopy (URS) in patients treated for proximal ureteral stones.Materials and Methods:Patients, who underwent URS for proximal ureteral stones at various urology clinics in Turkiye, were included in the study. The patients were divided into two groups according to the anesthesia method performed; the procedure was performed under spinal anesthesia (SA) in group 1 and general anesthesia (GA) in group 2. Patients’ demographic, perioperative data and complication rates were compared between the two groups in a retrospective manner.Results:There were 309 and 329 patients in groups 1 and 2, respectively. The mean stone area and Hounsfield unit in GA group were higher (p0.05). The rate of success of URS, which is accepted as complete stone-free status, was higher in the SA group (p=0.041).Conclusion:URS, which is used in the treatment of proximal ureteral stones, has a high success rate, independent of the anesthesia method used. It is important to keep in mind the patient’s comorbidities prior to selecting the anesthesia method and that the stone area and the Hounsfield unit are the important factors affecting the outcomes

Semitic Dialects and Dialectology

Characterised by the multiplicity and diversity of research and methodology, the European tradition of Semitic linguistics has always supported fieldwork and highly valued the data obtained in this way as it allows to create an interesting dynamic for linguistic studies itself. In the spirit of this tradition and to uphold it, the present book is a collection of articles based on data gathered primarily during field research expeditions. The volume is divided into two parts—Studies on various specific linguistic issues and Texts containing previously unpublished transcriptions of audio recordings in Arabic dialects, Maltese and Jibbali/Shehret.Die europäische Tradition der semitischen Linguistik, die sich durch Vielfalt der Forschungsmethoden auszeichnet, hat dialektologische Feldforschung immer hoch geschätzt, da die gewonnenen Sprachaufnahmen im Kontext der älteren Sprachformen gesetzt werden und somit eine hochgradig interessante Dynamik in der Sprachwissenschaft ermöglichen. Im Geiste dieser Tradition und um sie aufrechtzuerhalten, ist das vorliegende Buch eine Sammlung von Artikeln, deren Daten vor allem während der Feldforschung gesammelt wurden. Der Band gliedert sich in zwei Teile - Studien zu verschiedenen spezifischen linguistischen Fragestellungen und Texte mit bisher unveröffentlichten Transkriptionen von Audioaufnahmen in arabischen Dialekten, Maltesisch und Jibbali/Shehret