Design and Analysis of Shrouded Small-Scale Wind Turbine for Low Wind Speeds

This work presents design and analysis of a shrouded small scale wind turbine optimized for extremely low wind speeds. In-house FORTRAN code based on Glauert's method are used for preliminary design. QBlade and CFD are used for iterative optimization. Results show that power output can be increased 1.5-2.5 times by using shroud. Additionally, using shroud and optimizing for low wind speed solves starting problem that small scale wind turbines have considerably and increases sustainability of power production

Prognostic values of urea/lymphocyte and LDH/lymphocyte ratios for predicting mortality in COVID-19 patients

Objective: Serum biomarkers are important for accurately predicting clinical outcomes in coronavirus disease 2019 (COVID-19) patients. Although previous studies showed that lymphopenia in patients is related to disease severity, it is unclear how other serum biomarkers improve the prognostic accuracy of lymphopenia. Changes in urea, and lactate dehydrogenase (LDH) were noted to have considerable predictive value in determining the severity of disease in COVID-19 patients. Therefore, the purpose of this study is to determine whether increases in urea, and LDH are linked to worse outcomes in COVID-19 patients and whether the urea/lymphocyte and LDH/lymphocyte ratios improve the prognostic accuracy of lymphopenia. Methods: The data of confirmed COVID-19 patients in our emergency department (ED) between March 2020, and January 2021, were analyzed retrospectively. The area under the curve (AUC) and logistic regression analysis were used to evaluate the discriminative power of the urea/lymphocyte and LDH/lymphocyte ratios in estimating 30-day mortality. Results: The study included 795 confirmed COVID-19 patients admitted to the ED. Twenty-three patients (2.9%) died, and 772 (97.1%) survived in 30 days. The median age of the patients was 51. The number of males (n: 447, 56.2%) was higher than females (n: 348, 43.8%). The ratios of urea/lymphocyte and LDH/lymphocyte were significantly higher in non-survivors (median: 71.21 and 754.1, respectively) compared to survivors (median: 19.51 and 297.42, respectively) (P<0.001). The AUC for 30-day mortality for the urea/lymphocyte and LDH/lymphocyte ratios was 0.864 and 0.840, respectively. Multivariate logistic regression adjustment found the urea/lymphocyte ratio to be an independent and significant predictor of mortality (P=0.007). The optimum cut-off point for the urea/lymphocyte ratio was 28.07, which had a 91.3% sensitivity and a 68.6% specificity. Conclusion: The urea/lymphocyte and LDH/lymphocyte ratios are useful markers that can be evaluated independently to identify high-risk patients and predict the prognosis of COVID-19

Three-year clinical performance of two indirect composite inlays compared to direct composite restorations

Objective: Despite the incremental build-up of resin composite restorations, their polymerization shrinkage during curing presents a serious problem. Indirect composite resin systems represent an alternative in overcoming some of the deficiencies of direct composite restorations. The hypothesis of the present study states that the clinical performance of restorations may be affected by different generation and application techniques. Study Design: Sixty restorations (20 DI system (Coltène/Whaledent AG, Altstätten, Switzerland) composite inlays, 20 Tescera ATL system (BISCO Inc. Schaumburg, Illinois, USA) composite inlays, and 20 direct composites) were applied to premolar teeth in 49 patients. Restorations were clinically evaluated by two examiners. Data were analyzed using the Kruskal-Wallis, Mann-Whitney U, Wilcoxon Signed Ranks, and X2 tests. Results: The Tescera ATL system performed significantly better than both direct composite restorations (p<0.001) and DI system (p<0.05). Conclusion: Within the limitations of this 3-year clinical study, indirect resin restorations showed better scores than direct restorations. In addition, the Tescera ATL system was found to be more successful than the DI system and direct composite restorations

A New Side Effect of Intravitreal Dexamethasone Implant (Ozurdex®)

Dexamethasone implant, 0,7 mg (Ozurdex, Allergan, Inc., Irvine, CA, USA), is drug mostly used in the treatment of the diabetic macular edema and edema related to retinal vein occlusion. By reporting this case we aimed to report a new side effect of 0.7 mg intravitreal dexamethasone implant that has not been reported in the literature before

TURKISH JOURNAL of ONCOLOGY Leptomeningeal Carcinomatosis in a Krukenberg Tumor Associated with Signet Ring Cell Gastric Cancer

SUMMARY Leptomeningeal carcinomatosis (LCM) is a rare complication of gastric cancer. It usually occurs late in advanced stage of disease and is sometimes misdiagnosed as toxicity of chemotherapeutic agents. Here we report a rare case of gastric cancer that developed LCM in follow-up. A 28-year-old woman with signet ring cell gastric cancer associated with Krukenberg tumor was admitted with persistent headache, nausea, vomiting, vertigo, and diplopia. Linear appearance of contrast enhancement in cerebellar fissures and around cranial nerves was seen in magnetic resonance imaging and cerebrospinal fluid was hypercellular with numerous carcinoma cells. LMC was confirmed and treated with intrathecal methotrexate and additional whole-brain irradiation. LCM is a rare complication, but occurs more often than expected and is often misdiagnosed. If patient who is being treated for gastric cancer presents with neurological symptoms, LCM should be kept in mind. Clinical improvement can be achieved with current treatment modalities, including radiotherapy, chemotherapy, or targeted molecules

Monolithic Integration of Silicon Nanowires With a Microgripper

Si nanowire (NW) stacks are fabricated by utilizing the scalloping effect of inductively coupled plasma deep reactive ion etching. When two etch windows are brought close enough, scallops from both sides will ideally meet along the dividing centerline of the windows turning the separating material column into an array of vertically stacked strings. Upon further thinning of these NW precursors by oxidation followed by oxide etching, Si NWs with diameters ranging from 50 nm to above 100 nm are obtained. The pattern of NWs is determined solely by photolithography. Various geometries ranging from T-junctions to circular coils are demonstrated in addition to straight NWs along specific crystallographic orientations. The number of NWs in a stack is determined by the number of etch cycles utilized. Due to the precise lithographic definition of NW location and orientation, the technique provides a convenient batch-compatible tool for the integration of NWs with MEMS. This aspect is demonstrated with a microgripper, where an electrostatic actuation mechanism is simultaneously fabricated with the accompanying NW endeffectors. Mechanical integrity of the NW–MEMS bond and the manipulation capability of the gripper are demonstrated. Overall, the proposed technique exhibits a batch-compatible approach to the issue of micronanointegration

Chemical composition and antimicrobial activity of the commercial Origanum onites L. oil against nosocomial carbapenem resistant extended spectrum beta lactamase producer Escherichia coli isolates

In recent years rapidly growing antibiotic resistance has increased interest toward natural products, especially essential oils because of their various effects. The aim of this study was to identify the chemical composition of the commercial Origanum onites essential oil (EO) and to investigate the antimicrobial activity by disc diffusion and dilution methods, against ten different ATCC strains, including eight bacteria, two yeasts and seventy-nine clinical nosocomial Escherichia coli isolates that produce extended spectrum beta lactamase (ESBL). The chemical composition of EO was analyzed by GC and GC-MS. The major compounds of the EO were determined as carvacrol (51.4%) followed by linalool (11.2%), p-cymene (8.9%) and γ-terpinene (6.7%). O. onites EO had antimicrobial activity against all standard strains and inhibited microbial growth of ESBL positive E. coli isolates. According to our results, O. onites EO may be an alternative to synthetic drug, used in combination with other antibiotics for treatment of infection caused by multidrug resistant bacteria after testing toxic effects and irritation at preferred doses on human

Insertion trauma of a novel inner ear catheter for intracochlear drug delivery

IntroductionEven with recent research advances, effective delivery of a compound to its target cells inside the inner ear remains a challenging endeavor due to anatomical and physiological barriers. Direct intracochlear drug administration with an inner ear catheter (IEC) aims to overcome this obstacle and strives to provide a safe and efficient way for inner ear pharmacotherapy. The goal of this study was to histologically and audiologically evaluate the traumatic properties of a novel IEC for intracochlear drug delivery in a large animal model.MethodsSeven inner ears of piglets that had undergone intracochlear fluorescein isothiocyanate dextran application via an IEC (n = 4) or round window membrane (RWM) puncture with a needle (n = 3) followed by sequential apical perilymph sampling were histologically analyzed. Additionally, obtained objective auditory compound action potential and cochlear microphonic measurements were compared. Cochlear cryosections were stained using hematoxylin and eosin, and preservation of inner ear structures was investigated. Moreover, one cochlea was methylmethacrylate-embedded and analyzed with the IEC in situ.ResultsHistological evaluation revealed an atraumatic insertion and subsequent compound application in a majority of IEC-inserted inner ears. Click cochlear compound action potential (CAP) shifts in the IEC groups reached a maximum of 5 dB (1.25 ± 2.5 dB) post administration and prior to perilymph sampling. In comparison, application by RWM puncture generated a maximum click CAP hearing threshold shift of 50 dB (23.3 ± 23.1 dB) coinciding with coagulated blood in the basal cochlear turn in one specimen of the latter group. Furthermore, in situ histology showed an atraumatic insertion of the IEC demonstrating preserved intracochlear structures.ConclusionThe IEC appears to be a promising and efficient way for inner ear drug delivery. The similarities between the porcine and human inner ear enhance the clinical translation of our findings and increase confidence regarding the safe applicability of the IEC in human subjects

Monitoring the damage state of fiber reinforced composites using an FBG network for failure prediction

A structural health monitoring (SHM) study of biaxial glass fibre-reinforced epoxy matrix composites under a constant, high strain uniaxial fatigue loading is performed using fibre Bragg grating (FBG) optical sensors embedded in composites at various locations to monitor the evolution of local strains, thereby understanding the damage mechanisms. Concurrently, the temperature changes of the samples during the fatigue test have also been monitored at the same locations. Close to fracture, significant variations in local temperatures and strains are observed, and it is shown that the variations in temperature and strain can be used to predict imminent fracture. It is noted that the latter information cannot be obtained using external strain gages, which underlines the importance of the tracking of local strains internally