Design of a tunable multi-band differential LC VCO using 0.35 mu m SiGe BiCMOS technology for multi-standard wireless communication systems

In this paper, an integrated 2.2-5.7GHz multi-band differential LC VCO for multi-standard wireless communication systems was designed utilizing 0.35 mu m SiGe BiCMOS technology. The topology, which combines the switching inductors and capacitors together in the same circuit, is a novel approach for wideband VCOs. Based on the post-layout simulation results, the VCO can be tuned using a DC voltage of 0 to 3.3 V for 5 different frequency bands (2.27-2.51 GHz, 2.48-2.78 GHz, 3.22-3.53 GHz, 3.48-3.91 GHz and 4.528-5.7 GHz) with a maximum bandwidth of 1.36 GHz and a minimum bandwidth of 300 MHz. The designed and simulated VCO can generate a differential output power between 0.992 and -6.087 dBm with an average power consumption of 44.21 mW including the buffers. The average second and third harmonics level were obtained as -37.21 and -47.6 dBm, respectively. The phase noise between -110.45 and -122.5 dBc/Hz, that was simulated at 1 MHz offset, can be obtained through the frequency of interest. Additionally, the figure of merit (FOM), that includes all important parameters such as the phase noise, the power consumption and the ratio of the operating frequency to the offset frequency, is between -176.48 and -181.16 and comparable or better than the ones with the other current VCOs. The main advantage of this study in comparison with the other VCOs, is covering 5 frequency bands starting from 2.27 up to 5.76 GHz without FOM and area abandonment. Output power of the fundamental frequency changes between -6.087 and 0.992 dBm, depending on the bias conditions (operating bands). Based on the post-layout simulation results, the core VCO circuit draws a current between 2.4-6.3 mA and between 11.4 and 15.3 mA with the buffer circuit from 3.3 V supply. The circuit occupies an area of 1.477 mm(2) on Si substrate, including DC, digital and RF pads

Retinal Vein Passing through a Congenital Optic Nerve Pit

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The Relationship of Neutrophil to Lymphocyte Ratio with Vitreomacular Traction Syndrome

This study was conducted to reveal the role of systemic low-grade inflammation by calculating the Neutrophil/Lymphocyte Ratio (NLR) in Vitreomacular Traction Syndrome (VMTS) of different etiologies. A retrospective examination was made of the medical records at a tertiary referral hospital. The study included 31 patients with diabetic VMTS, 27 patients with idiopathic VMTS, and 35 healthy subjects as the control group. The White Blood Cell (WBC) counts and Neutrophil-to-Lymphocyte Ratio (NLR) was compared. There were  insignificant differences between the groups in terms of mean age and female/male ratio (P>0.05). The mean ± Standard Deviation (SD) of NLR was calculated as 2.43 ± 0.83 in the diabetic VMTS group, 2.38 ± 0.96 in the idiopathic VMTS group, and 1.83 ± 0.52 in the control group (P=0.007). The values of the diabetic and idiopathic VMTS groups were significantly higher than those of the control group (P=0.002 and P=0.032, respectively). However, differences between the diabetic and idiopathic VMTS groups were insignificant (P=0.651). This study found significantly higher NLR in patients with diabetic and idiopathic VMTS than the control group. Elevated NLR could therefore be a potential indicator of VMTS, irrespective of the etiology

Amputation of an Extra-root with an Endodontic Lesion in an Invaginated Vital Maxillary Lateral Incisor: A Rare Case with Seven-year Follow-up

The developmental abnormality of tooth resulting from the infolding of enamel/dentin into the root is called dens invaginatus. Management of such cases is usually challenging due to the morphological complexity of root canal system. This report presents a rare treatment protocol of a clinical case of Oehler’s type III dens invaginatus combined with an endodontic lesion in a vital maxillary lateral incisor. Access to the endodontic lesion located between the central and lateral incisors was achieved by reflection of a full mucoperiosteal flap. Granulomatous tissue as well as aberrant root was removed and the surface of the root and adjacent coronal region were reshaped. Three years later, the patient was orthodontically treated. Seven years after completion of surgical/orthodontic management, the tooth remained asymptomatic and functional with normal periodontium/vital pulp. Radiographically, the healing of the lesion was observed. Actually, vitality of the invaginated tooth and communication between the invagination and the root canal were the most important factors in determining such minimally invasive treatment protocol. Depending on the anatomy of the root canal system, surgical amputation of an invaginated root can be performed to achieve a successful outcome in Oehler’s type III dens invaginatus cases, even though it is associated with apical periodontitis.Keywords: Apical Periodontitis; Dens Invaginatus; Endodontic Therapy; Lateral Incisor; Periradicular Surger

A rare congenital anomaly: Pulmonary atresia and abnormal origin of right pulmonary artery

2MAR2041

Confocal Scanning Laser Microscopy in Medicine

Confocal Scanning Laser Microscopy (CSLM) offers high resolution morphological details and generates en-face images with excellent depth discrimination for visualizing different structures of the living human body non-invasively. There have been significant advances in technology since the CSLM was first defined. It has been used commonly, especially in ophthalmological area, in order to diagnose and give direction for the treatment of corneal pathologies. Ocular surface, corneal subbasal nerve plexus, filtering blebs of glaucoma surgery were also investigated widely by CSLM. With the improvements in CSLM technology over time, it is widely used in other fields than ophthalmology. The combined use of CSLM with the slit lamp biomicroscopy and optical coherence tomography will also lead to significant advances in the diagnosis and treatment of more diseases in the future

Increased mRNA expression of ADAMTS1 and ADAMTS4 in peripheral blood mononuclear cells of psoriasis patients developed psoriatic arthritis

Background and purpose: Psoriatic arthritis (PsA) is a chronic inflammatory disease associated with psoriasis (PsO) affecting both skin and joint. ADAMTS (A disintegrin-like and metalloproteinase domain with thrombospondin-1 repeats) is a large family of proteoglycanase enzymes and the expression levels of ADAMTS proteases are upregulated in arthritis. In this study, we aimed to determine mRNA expression levels of ADAMTS1, ADAMTS4 and ADAMTS5 and identifying the key signaling pathways involved in the regulation of these proteases in peripheral blood mononuclear cells (PBMCs) of patients with PsO who later developed PsA. Materials and methods: 25 PsA patients, 25 PsO patients and 25 healthy individuals were included in this study. PBMCs were isolated from venous blood and mRNA expression levels of ADAMTS1, ADAMTS4 and ADAMTS5 were measured through Real-time quantitative PCR (RTqPCR). Results: mRNA expression levels of ADAMTS1 and ADAMTS4 were found to be increased in PsA patients compared with control and PsO patients. In response to TNF-a stimulation, the expression of ADAMTS1 in PsA patients was determined to be reduced in a Erk1/2 activity dependent manner, whereas p38 and JNK activities were shown to induce the expression of ADAMTS4 in PsA patients. The reduced ADAMTS1 expression in PsA patients induced by IL-1b stimulation was revealed to be dependent on NFkB activity. Conclusions: mRNA expressions of ADAMTS1 and ADAMTS4 regulated by MAPKs and NFkB were increased in PBMCs of PsA patients. This study supports the hypothesis that ADAMTS1 and ADAMTS4 mRNA level might be diagnostic markers for identifying psoriatic patients who are more likely to develop PsA and a future drug target for PsA treatment