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Optical receivers based on graphene still suffer from low responsivity. Here, the authors integrate a photo-thermoelectric graphene photodetector with a Si micro-ring resonator, and obtain a voltage responsivity ~ 90 V/W and a reduction of energy-per-bit consumption, enabling performance on par with mature semiconductor technology.

The main limitation to the areal storage density of hard disk drives (HDDs) is the thickness of carbon overcoats protecting the disk media. Here,

Next-generation data networks need to support Tb/s rates. In-phase and quadrature (IQ) modulation combine phase and intensity information to increase the density of encoded data, reduce overall power consumption by minimizing the number of channels, and increase noise tolerance. To reduce errors when decoding the received signal, intersymbol interference must be minimized. This is achieved with pure phase modulation, where the phase of the optical signal is controlled without changing its intensity. Phase modulators are characterized by the voltage required to achieve a π phase shift, V π , the device length, L , and their product, V π L . To reduce power consumption, IQ modulators are needed with <1 V drive voltages and compact (sub-cm) dimensions, which translate in V π L < 1Vcm. Si and LiNbO 3 (LN) IQ modulators do not currently meet these requirements because V π L > 1Vcm. Here, we report a double single-layer graphene (SLG) Mach-Zehnder modulator (MZM) with pure phase modulation in the transparency regime, where optical losses are minimized and remain constant with increasing voltage. Our device has V π L ∼ 0.3Vcm, matching state-of-the-art SLG-based MZMs and plasmonic LN MZMs, but with pure phase modulation and low insertion loss (∼5 dB), essential for IQ modulation. Our V π L is ∼5 times lower than the lowest thin-film LN MZMs and ∼3 times lower than the lowest Si MZMs. This enables devices with complementary metal-oxide semiconductor compatible V π L (<1Vcm) and smaller footprint than LN or Si MZMs, improving circuit density and reducing power consumption by 1 order of magnitude.

Objectives: Posttransplant lymphoproliferative disorder is a consequential complication following solid-organ transplant, particularly associated with the Epstein-Barr virus. We studied a single center's cases of pediatric posttransplant lymphoproliferative disorder for a 7-year period and focused on incidence rates, anatomic sites involved, and correlation with clinical outcomes. We explored clinical features and treatment outcomes in patients with pediatric posttransplant lymphoproliferative disorder, with emphasis on patient survival and associated clinical ramifications., Materials and Methods: This was a retrospective analysis of medical records from pediatric solid-organ transplant recipients (liver or kidney) at Baskent University Ankara Hospital Organ Transplantation Center between January 1, 2017, and January 1, 2024, approved by the Institutional Review Board (KA24/63). We identified cases based on pathology-confirmed persistent lymphadenopathy or tumorous lesions. Patient categorization distinguished between malignant and benign groups. Early posttransplant lymphoproliferative disorder was defined within the initial year after transplant. Epstein?Barr virus association was determined through in situ hybridization, and patient characteristics were reviewed comprehensively., Results: In 7 years, 10 pediatric patients (9 liver transplants, 1 kidney transplant) were diagnosed with posttransplant lymphoproliferative disorder, with an incidence of 8.7% for pediatric liver transplants. Mean age at diagnosis was 46.4 months, and mean time from transplant to diagnosis was 21.2 months. The most common complaints at diagnosis included fever, lymphadenopathy, hepatosplenomegaly, dyspnea, and diarrhea. Treatment modalities included rituximab, immunosuppression reduction, intravenous immunoglobulin therapy, and chemotherapy (NHL Berlin-Frankfurt-Münster 90 protocols). All patients achieved remission (mean follow-up, 22.9 mo)., Conclusions: Early diagnosis of posttransplant lymphoproliferative disorder is important, and rituximab with immunosuppression reduction is effective to achieve complete remission, particularly in early polymorphic cases. Despite challenges, all patients achieved remission, signaling improved outcomes in pediatric posttransplant lymphoproliferative disorder. Active monitoring of Epstein?Barr virus infection may further reduce posttransplant lymphoproliferative disorder complications in pediatric solid-organ transplant; hence, early diagnosis is crucial.

The integration of optoelectronic devices, such as transistors and photodetectors (PDs), into wearables and textiles is of great interest for applications such as healthcare and physiological monitoring. These require flexible/wearable systems adaptable to body motions, thus materials conformable to non-planar surfaces, and able to maintain performance under mechanical distortions. Here, fibre PDs are prepared by combining rolled graphene layers and photoactive perovskites. Conductive fibres (~500 Ωcm -1 ) are made by rolling single-layer graphene (SLG) around silica fibres, followed by deposition of a dielectric layer (Al 2 O 3 and parylene C), another rolled SLG as a channel, and perovskite as photoactive component. The resulting gate-tunable PD has a response time~9ms, with an external responsivity~22kAW -1 at 488nm for a 1V bias. The external responsivity is two orders of magnitude higher, and the response time one order of magnitude faster, than state-of-the-art wearable fibre-based PDs. Under bending at 4mm radius, up to~80% photocurrent is maintained. Washability tests show~72% of initial photocurrent after 30 cycles, promising for wearable applications., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Single-crystal graphene (SCG) wafers are needed to enable mass-electronics and optoelectronics owing to their excellent properties and compatibility with silicon-based technology. Controlled synthesis of high-quality SCG wafers can be done exploiting single-crystal Cu(111) substrates as epitaxial growth substrates recently. However, current Cu(111) films prepared by magnetron sputtering on single-crystal sapphire wafers still suffer from in-plane twin boundaries, which degrade the SCG chemical vapor deposition. Here, it is shown how to eliminate twin boundaries on Cu and achieve 4 in. Cu(111) wafers with ≈95% crystallinity. The introduction of a temperature gradient on Cu films with designed texture during annealing drives abnormal grain growth across the whole Cu wafer. In-plane twin boundaries are eliminated via migration of out-of-plane grain boundaries. SCG wafers grown on the resulting single-crystal Cu(111) substrates exhibit improved crystallinity with >97% aligned graphene domains. As-synthesized SCG wafers exhibit an average carrier mobility up to 7284 cm 2 V -1 s -1 at room temperature from 103 devices and a uniform sheet resistance with only 5% deviation in 4 in. region., (© 2023 Wiley‐VCH GmbH.)

Harmonic generation is a result of a strong non-linear interaction between light and matter. It is a key technology for optics, as it allows the conversion of optical signals to higher frequencies. Owing to its intrinsically large and electrically tunable non-linear optical response, graphene has been used for high harmonic generation but, until now, only at frequencies < 2 THz, and with high-power ultrafast table-top lasers or accelerator-based structures. Here, we demonstrate third harmonic generation at 9.63 THz by optically pumping single-layer graphene, coupled to a circular split ring resonator (CSRR) array, with a 3.21 THz frequency quantum cascade laser (QCL). Combined with the high graphene nonlinearity, the mode confinement provided by the optically-pumped CSRR enhances the pump power density as well as that at the third harmonic, permitting harmonic generation. This approach enables potential access to a frequency range (6-12 THz) where compact sources remain difficult to obtain, owing to the Reststrahlenband of typical III-V semiconductors., (© 2024. The Author(s).)

Neurosteroids (NSs) are endogenous steroid hormones, which are synthesised and metabolised within the central nervous system (CNS). NSs aid myelination and glial differentiation and modulate cognitive functions. Herein, we aim to investigate the relationship between NS levels, 5-alpha-dihydroxyprogesterone (5-α-DHP) and allopregnanolone (ALPG), and their relationship with cognitive changes in relapsing remitting MS patients.A total of 43 cases with well controlled, relapsing remitting MS composed the study group. The control group included 21 age and gender matched healthy controls (HC). MS patients were assessed by calculating Expanded Disability Status Scale (EDSS) scores, and the Brief Repeatable Battery of Neuropsychological Tests (BRBNT) was performed in both MS group and HC. Levels of 5-α-DHP and ALPG levels were also evaluated for each participant.The median level of 5-α-DHP was 48 [IQR: 39.2-144.2] pg/mcgL in the MS group and 68.4 [IQR: 57.1-365.9] pg/mcgL in HC ( p  = 0.02). The median ALPG level was found to be 56.5 [IQR: 37.7-75.4] pg/mcgL in the MS group and 43.9 [IQR: 29.4-70.2] pg/mcgL in HC ( p  = 0.1). In both groups 5-α-DHP levels were positively correlated with Symbol Digit Modalities Test (SDMT) scores (HC: p = 0.01, r  = 0.3 and MS: p  = 0.03, r  = 0.3). In the MS group, higher EDSS scores were associated with lower scores on Spatial Recall Test (SPART)-Delayed ( p  = 0.009, r = -0.4) and SDMT ( p  = 0.01, r = -0.4). The disease duration was negatively correlated with the scores on SPART-Immediate, SPART-Delayed and SDMT ( p  = 0.02, r = -0.4; p  = 0.005, r = -0.4 and p  = 0.05, r = -0.3).5-α-DHP may be lower even in well-controlled cases. 5-α-DHP may contribute to better perceptual processing and attention in cases with MS.

Polaritons in layered materials (LMs) are a promising platform to manipulate and control light at the nanometer scale. Thus, the observation of polaritons in wafer-scale LMs is critically important for the development of industrially relevant nanophotonics and optoelectronics applications. In this work, phonon polaritons (PhPs) in wafer-scale multilayer hexagonal boron nitride (hBN) grown by chemical vapor deposition are reported. By infrared nanoimaging, the PhPs are visualized, and PhP lifetimes of ≈0.6 ps are measured, comparable to that of micromechanically exfoliated multilayer hBN. Further, PhP nanoresonators are demonstrated. Their quality factors of ≈50 are about 0.7 times that of state-of-the-art devices based on exfoliated hBN. These results can enable PhP-based surface-enhanced infrared spectroscopy (e.g., for gas sensing) and infrared photodetector applications., (© 2023 Wiley-VCH GmbH.)

Graphene is a nonlinear material in the terahertz (THz) frequency range, with χ (3) ∼ 10 -9 m 2 /V 2 ∼ 15 orders of magnitude higher than that of other materials used in the THz range, such as GaAs or lithium niobate. This nonlinear behavior, combined with ultrafast dynamic for excited carriers, proved to be essential for third harmonic generation in the sub-THz and low (<2.5 THz) THz range, using moderate (60 kV/cm) fields and at room temperature. Here, we show that, for monochromatic high peak power (1.8 W) input THz signals, emitted by a quantum cascade laser, the nonlinearity can be controlled using an ionic liquid gate that tunes the graphene Fermi energy up to >1.2 eV. Pump and probe experiments reveal an intense absorption nonlinearity at 3.2 THz, with a dominant 3rd-order contribution at E F > 0.7 eV, hence opening intriguing perspectives per engineering novel architectures for light generation at frequencies > 9 THz., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

The ability to tune the optical response of a material via electrostatic gating is crucial for optoelectronic applications, such as electro-optic modulators, saturable absorbers, optical limiters, photodetectors, and transparent electrodes. The band structure of single layer graphene (SLG), with zero-gap, linearly dispersive conduction and valence bands, enables an easy control of the Fermi energy, E F , and of the threshold for interband optical absorption. Here, we report the tunability of the SLG nonequilibrium optical response in the near-infrared (1000-1700 nm/0.729-1.240 eV), exploring a range of E F from -650 to 250 meV by ionic liquid gating. As E F increases from the Dirac point to the threshold for Pauli blocking of interband absorption, we observe a slow-down of the photobleaching relaxation dynamics, which we attribute to the quenching of optical phonon emission from photoexcited charge carriers. For E F exceeding the Pauli blocking threshold, photobleaching eventually turns into photoinduced absorption, because the hot electrons' excitation increases the SLG absorption. The ability to control both recovery time and sign of the nonequilibrium optical response by electrostatic gating makes SLG ideal for tunable saturable absorbers with controlled dynamics.

Objectives: This was a retrospective analysis of liver transplant for pediatric patients with liver cirrhosis and hepatocellular carcinoma., Materials and Methods: Fourteen pediatric patients with chronic liver disease and hepatocellular carcinoma underwent liver transplant from 2004 to 2021. Preexisting diseases were tyrosinemia (n = 6), progressive familial intrahepatic cholestasis type 2 (n = 2) and type 3 (n = 3), cryptogenic cirrhosis (n = 2), hepatitis B and D (n = 1), and biliary atresia (n = 1)., Results: Mean age was 9.43 ± 4.9 years (range, 13 months to 16 years). Three patients had 1 tumor, 4 had 2 tumors, and 7 had multiple (≥3) lesions. Six patients were classified as Pretreatment Extent of Disease Staging System for Hepatoblastoma (PRETEXT) stage IV, 3 as stage II, and 5 as stage I. Some patients received systemic chemotherapy before (n = 4) or after transplant (n = 3) or transarterial chemoembolization and microwave ablation pretransplant (n = 1). Hepatocellular carcinoma posttransplant recurrence was observed at 23, 47, and 108 months in 3 patients (21%). Recurrence sites were omentum (n = 1) and liver graft (n = 2). One patient was treated with hepatic resection, radiofrequency ablation, and radiotherapy, while the other received radiofrequency ablation and chemotherapy for graft tumor recurrence. Relapse-free patient survival rates were 92%, 82.5%, and 72.2% at 2, 4, and 10 years, respectively. Four recipients (28.5%) died; posttransplant cause of death was infection at 19 (n = 1) and 188 months (n = 1) or hepatocellular carcinoma recurrence at 79 (n = 1) and 165 months (n = 1). Median follow-up was 178 months (range, 13-204 months). Mean estimated survival was 171.25 ± 16.6 months. Overall patient posttransplant survival was 100%, 92.3%, 92.3%, 83%, and 72% at 1, 2, 5, 10, and 15 years, respectively., Conclusions: Hepatocellular carcinoma was mainly associated with inherited liver diseases in our pediatric series. Liver transplant provided a long-term survival advantage to pediatric patients with preexisting cirrhosis and hepatocellular carcinoma.

The scalable synthesis and transfer of large-area graphene underpins the development of nanoscale photonic devices ideal for new applications in a variety of fields, ranging from biotechnology, to wearable sensors for healthcare and motion detection, to quantum transport, communications, and metrology. We report room-temperature zero-bias thermoelectric photodetectors, based on single- and polycrystal graphene grown by chemical vapor deposition (CVD), tunable over the whole terahertz range (0.1-10 THz) by selecting the resonance of an on-chip patterned nanoantenna. Efficient light detection with noise equivalent powers <1 nWHz -1/2 and response time ∼5 ns at room temperature are demonstrated. This combination of specifications is orders of magnitude better than any previous CVD graphene photoreceiver operating in the sub-THz and THz range. These state-of-the-art performances and the possibility of upscaling to multipixel architectures on complementary metal-oxide-semiconductor platforms are the starting points for the realization of cost-effective THz cameras in a frequency range still not covered by commercially available microbolometer arrays.

Aims: Amelogenesis imperfecta and generalised enamel hypoplasia are developmental dental anomalies that affect dental enamel. While amelogenesis imperfecta results from various gene mutations, the exact underlying mechanisms of the etiopathogenesis of both remain unclear. This study aims to evaluate Ghrelin hormone levels in children with generalised enamel hypoplasia to establish whether Ghrelin might have a potential role in enamel hypoplasia's etiology. The second purpose is to determine the correlations among the blood levels of Ghrelin, growth hormone (GH), insulin-like growth factor-1 (IGF-1), bone alkaline phosphatase (BALP) and osteocalcin (OC) that are vital in dental development., Material and Methods: Study was designed with two study groups, AI (hypoplastic amelogenesis imperfecta) (n = 15; mean-age 10.36 ± 1.90) and GEH (idiopathic generalised enamel hypoplasia) (n = 15; mean-age 10.42 ± 1.84), and a healthy control (n = 15; mean-age 10.39 ± 1.91) group. After fasting for 10-12 hours, simultaneous blood samples were collected; then, after centrifugation, serum and plasma were stored at -80°C until the day of analysis. Total Ghrelin levels of plasma and serum levels of GH, IGF-1, BALP and OC were measured using commercial ELISA kits., Results: Ghrelin levels of AI and GEH groups were significantly lower (P < .01) than the control group., Conclusion: This is the first study to reveal the decreased levels of Ghrelin in plasma of children with generalised enamel hypoplasia, suggesting a potential role for Ghrelin in amelogenesis. In order to determine its function in enamel formation, further studies should be carried out. The result of the present study suggests that paediatricians refer children with abnormal Ghrelin levels to a paediatric dentist to contribute to appropriate prophylactic and therapeutic interventions. Generalised enamel hypoplasia may also indicate possible abnormalities in Ghrelin levels for paediatricians. Therefore, paediatricians' knowledge about the clinical appearance of generalised enamel hypoplasia should be increased., (© 2021 John Wiley & Sons Ltd.)

Graphene integrated photonics provides several advantages over conventional Si photonics. Single layer graphene (SLG) enables fast, broadband, and energy-efficient electro-optic modulators, optical switches and photodetectors (GPDs), and is compatible with any optical waveguide. The last major barrier to SLG-based optical receivers lies in the current GPDs' low responsivity when compared to conventional PDs. Here we overcome this by integrating a photo-thermoelectric GPD with a Si microring resonator. Under critical coupling, we achieve >90% light absorption in a ~6 μm SLG channel along a Si waveguide. Cavity-enhanced light-matter interactions cause carriers in SLG to reach ~400 K for an input power ~0.6 mW, resulting in a voltage responsivity ~90 V/W, with a receiver sensitivity enabling our GPDs to operate at a 10 -9 bit-error rate, on par with mature semiconductor technology, but with a natural generation of a voltage, rather than a current, thus removing the need for transimpedance amplification, with a reduction of energy-per-bit, cost, and foot-print.

Hard disk drives (HDDs) are used as secondary storage in digital electronic devices owing to low cost and large data storage capacity. Due to the exponentially increasing amount of data, there is a need to increase areal storage densities beyond ~1 Tb/in 2 . This requires the thickness of carbon overcoats (COCs) to be <2 nm. However, friction, wear, corrosion, and thermal stability are critical concerns below 2 nm, limiting current technology, and restricting COC integration with heat assisted magnetic recording technology (HAMR). Here we show that graphene-based overcoats can overcome all these limitations, and achieve two-fold reduction in friction and provide better corrosion and wear resistance than state-of-the-art COCs, while withstanding HAMR conditions. Thus, we expect that graphene overcoats may enable the development of 4-10 Tb/in 2 areal density HDDs when employing suitable recording technologies, such as HAMR and HAMR+bit patterned media.

Purpose of the Study: The aim of this study was to show the clinical results of postoperative evaluation of cases of imperforate hymen that presented at our center during a 21-year period., Methods: A Foley's catheter was inserted in 74 patients of imperforate hymen who reported to the Department of Obstetrics and Gynecology, Meram Faculty of Medicine, Necmettin Erbakan University, between January 1, 1996, and December 31, 2016 with history of pelvic pain. In each case, the hymen was opened via a circular incision from the central of the distended. A Foley's catheter was inserted, and estrogen cream was prescribed for application on the hymenal structure for 14 days. The catheter was removed after 14 days., Results: The mean age of the patients at the time of this study was 28.3 ± 2.6 years, and the mean age at diagnosis was 13.2 ± 2.5 years. Twenty-nine (96.6%) patients had experienced vaginal bleeding during their first sexual intercourse experience, and one patient (3.4%) had not. Fourteen out of the 30 married women had become pregnant, of whom nine had delivered vaginally and five had delivered via a cesarean section. After undergoing renal ultrasound, none of the patients had any apparent anomalies. Only one patient had a uterine anomaly, which was a bicornuate uterus., Conclusion: A circular incision with insertion of Foley's catheter prevents many social problems by preserving the hymen's architecture and allowing vaginal bleeding to occur during the first sexual intercourse experience., Competing Interests: Conflict of interestNo conflict of interest was declared by the authors., (© Federation of Obstetric & Gynecological Societies of India 2021.)

Background: Alopecia areata (AA) is a common immune-mediated disorder. Destruction of anagen hair follicles by cytotoxic T cells (CTL) plays a major role in the pathogenesis of AA. Serum granulysin has been shown to reflect overall activity of CTLs., Aims: In this study, we aimed to compare serum granulysin levels in patients with AA before and after therapy and to analyze correlation between serum granulysin levels and disease severity., Methods: We evaluated the Severity of Alopecia Tool (SALT) score and serum granuysin levels of 38 AA patients at baseline and at 6th month of therapy. Thirty-three patients were treated with tofacitinib 5 mg b.i.d, and five patients were treated with topical immunotherapy. Serum granulysin levels were measured by enzyme-linked immunosorbent assay., Results: A moderate correlation was found between SALT scores and serum granulysin level at baseline (r = .378, P = .019). Baseline serum granulysin levels were significantly higher in patients with alopecia totalis/universalis compared with patients with patchy AA (P = .004, Z = 2.778). Serum granulysin levels significantly decreased in patients treated with tofacitinib compared to baseline (P = .001). The reduction in serum granulysin levels after tofacitinib therapy correlated with the reduction in SALT scores (P = .001)., Conclusions: Our results suggest serum granulysin levels to be a good correlate of immunological activity of AA. We also assume granulysin to be a potential mediator of follicle attack, the effects of which is blocked by tofacitinib therapy. Therefore, changes in serum granulysin levels under therapy can reflect the downregulation of immunological activity of AA., (© 2020 Wiley Periodicals LLC.)

Objectives: We aimed to compare the results of biomicroscopic examination and light microscopy in the diagnosis of Demodex infestation in chronic blepharitis cases., Methods: The study was performed with retrospective data and included patients with chronic blepharitis and who were admitted to the Medipol University Ophthalmology Outpatient Clinic. Biomicroscopic evaluation was performed intentionally under 40x magnification to investigate the presence of Demodex ectoparasites. Three or four pieces of eyelashes were obtained from all cases with epilation technique, and Demodex parasites were examined under ×100 and ×400 magnifications with light microscopy. The presence of one or more Demodex parasites in the examined area under light microscopy was considered to be positive for infestation. We calculated sensitivity, specificity, false-positive rate, false-negative rate, and positive and negative predictive values of biomicroscopic examination compared with those of positive light microscopy., Results: Of the 255 subjects included in the study, 134 (52.5%) were men and 121 (47.5%) were women. The mean age was 43.9±11.9 years. Of the 255 chronic blepharitis cases, 130 (51%) presented Demodex infestation on light microscopy. We calculated the sensitivity, specificity, false-positive rate, false-negative rate, positive predictive value, and negative predictive value and were found to be 83.07%, 90.4%, 9.6%, 16.9%, 90%, and 83.7%, respectively, for the biomicroscopic examination., Conclusions: Careful biomicroscopic examination can be time-efficient and cost-effective, and the need for more advanced and invasive procedures for the identification of Demodex in patients with chronic blepharitis can be reduced.

Plasmonic biosensing has emerged as the most sensitive label-free technique to detect various molecular species in solutions and has already proved crucial in drug discovery, food safety and studies of bio-reactions. This technique relies on surface plasmon resonances in ~50 nm metallic films and the possibility to functionalize the surface of the metal in order to achieve selectivity. At the same time, most metals corrode in bio-solutions, which reduces the quality factor and darkness of plasmonic resonances and thus the sensitivity. Furthermore, functionalization itself might have a detrimental effect on the quality of the surface, also reducing sensitivity. Here we demonstrate that the use of graphene and other layered materials for passivation and functionalization broadens the range of metals which can be used for plasmonic biosensing and increases the sensitivity by 3-4 orders of magnitude, as it guarantees stability of a metal in liquid and preserves the plasmonic resonances under biofunctionalization. We use this approach to detect low molecular weight HT-2 toxins (crucial for food safety), achieving phase sensitivity~0.5 fg/mL, three orders of magnitude higher than previously reported. This proves that layered materials provide a new platform for surface plasmon resonance biosensing, paving the way for compact biosensors for point of care testing.

Background: There is a mutual dynamic interaction between thyroid volume (TV), insulin-like growth factor-1 (IGF-1), and body mass index (BMI). These covariates undergo a change with the transition into puberty. The heterogeneity of the variates and study populations complicate the evaluation of the role of pure pubertal effect., Objective: The purpose of this study was to investigate the effect of puberty on IGF-1 and TV in a predetermined homogenous population such as obese children., Subjects and Methods: Three hundred and eighty children (202 girls and 178 boys) aged between 6 and 18 were enrolled in this prospective study. The children were assigned to two groups according to their pubertal status, i.e., prepubertal (n = 169) and postpubertal (n = 211). According to age and sex, the obese group (n = 222) was made up of children at and above the 95 th percentile, and the control group (n = 158) of children under the 85 th percentile. The following parameters were evaluated in all children: BMI, pubertal status, TV, and serum IGF-1, IGFBP-3, and IGF-1:IGFBP-3 molar ratio., Results: In comparison to the prepubertal obese group, the obese group at Tanner stage 2 had a larger mean TV (P = 0.008) and higher IGF-1 level (P = 0.033). There was a positive correlation between IGF-1 and TV both in the prepubertal and pubertal group (r 169 = 0.369, P = 0.001; r 211 = 0.316, P = 0.004, respectively), whereas there was no correlation between IGF-1 and BMI (r 169 = 0.99, P = 0.092; r 211 = 0.094, P = 0.088, respectively)., Conclusion: This study showed that the TV and serum IGF-1 levels were increased in obese children in the early stage of puberty and that there was a positive correlation between these two variables in all children, which shows the specific effect of the early stage of puberty on the increase in TV and IGF-1 levels and suggests that increased TV is associated with the increase in IGF-1 levels in a homogenous group such as obese children., Competing Interests: None

Objective: Several studies have established a relationship between low serum vitamin D levels and the onset of asthma in childhood. In this study, we aim to assess the relationship between vitamin D and asthma., Methods: This study included 29 mild and 30 moderate persistent asthma and 38 healthy control group. Evaluation of the three groups was carried out in respect of serum vitamin D levels, Respiratory Function Test (RFT), and Exercise Provocation Test (EPT). The two asthma groups were also examined using the Asthma Control Test (ACT) and Nitric Oxide in Exhaled Breath (FeNO) level., Results: The vitamin D levels of the mild and the moderate persistent asthma groups were determined to be lower than the vitamin D levels of the control group (p=0.007). A significant negative correlation was determined in all cases between the vitamin D levels and the broncho-reversibility percentage (p=0.0002). The negative correlation between the vitamin D levels and the broncho-reversibility percentage was more evident in the moderate persistent asthma group (p=0.0001). In the moderate persistent asthma group, a significant positive correlation was determined between the lowness of the maximum forced expiratory volume in EPT and a low vitamin D level (p=0.009). The ACT scores were lower, and the FeNO levels were higher in the moderate asthma group compared to the mild asthma group (p=0.0001)., Conclusion: The findings showed that low serum vitamin D levels were observed more often in children with asthma, and there was a correlation with increased broncho-reversibility in the RFT and increased bronchial hyper-reactivity in the EPT., Competing Interests: Conflict of Interest: No conflict of interest was declared by the authors., (Copyright: © 2019 by Istanbul Northern Anatolian Association of Public Hospitals.)

Purpose: Adnexal torsion constitutes 2.7% of gynecological emergencies, it is more frequently seen in reproductive age. Delay in diagnosis and treatment may lead to loss of the ovary. In this study, we aimed to assess patients who had adnexal torsion and compare laparoscopy with laparotomy in the treatment of these patients and point the most appropriate surgery according to age groups of the patients and comparison of patient characteristics and management between adnexal torsion in postmenopausal and premenopausal patients., Materials and Methods: This study was carried out in Necmettin Erbakan University, Meram Medicine Faculty, Department of Obstetrics and Gynecology. The study retrospectively analyzed 380 patients presented to our clinic with abdominal pain between January 2005 and December 2017 and had surgery for adnexal torsion., Results: The study included 380 patients who had surgery for adnexal torsion. A total of 220 patients had laparoscopy and 160 patients had laparotomy. Laparoscopy group consisted of young patients with low parity, whereas laparotomy group consisted of 160 patients of which 92 (57.5%) were in menopause. Teratomas were the most common pathological finding followed by follicular cysts. Fourteen ovarian malignancies and 11 borderline tumors had been reported. Eleven ovarian malignancies had been reported in postmenopausal patients and three in premenopausal patients., Conclusion: Laparoscopic surgery is preferred for young patients who want to preserve their fertility, but postmenopausal ovarian masses presenting with torsion should be analyzed with frozen section whenever possible, if not possible or not conclusive, staging surgery is more appropriate especially if there is suspicion of malignancy.

Purpose: To assess retinal and choroidal thickness changes in eyes with a first episode of unilateral non granulomatous acute anterior uveitis (AU)., Methods: Thirty-one patients with acute unilateral non granulomatous AU who had undergone spectral domain optical coherence tomography (SD-OCT) of both eyes were included in this retrospective study. Retinal thickness (RT) as defined by the Early Treatment Diabetic Retinopathy Study (ETDRS) and subfoveal choroidal thickness (SFCT) obtained by SD-OCT were recorded. Healthy fellow eyes of the patients served as the control., Results: A significant thickening in 1mm of ETDRS subfield and in subfoveal choroid was observed in eyes with acute AU when compared with the unaffected fellow eyes (P=0.005 and P<0.00001, respectively). RT and SFCT of affected eyes did not show a significant difference in terms of HLA-B27 antigen presence or absence (P>0.05, for all)., Conclusions: Significant posterior segment changes were detected in eyes with acute unilateral non granulomatous AU., (Copyright © 2018. Published by Elsevier Masson SAS.)

The etiology of intellectual disability (ID) is heterogeneous including a variety of genetic and environmental causes. Historically, most research has not focused on autosomal recessive ID (ARID), which is a significant cause of ID, particularly in areas where parental consanguinity is common. Identification of genetic causes allows for precision diagnosis and improved genetic counseling. We performed whole exome sequencing to 21 Turkish families, seven multiplex and 14 simplex, with nonsyndromic ID. Based on the presence of multiple affected siblings born to unaffected parents and/or shared ancestry, we consider all families as ARID. We revealed the underlying causative variants in seven families in MCPH1 (c.427dupA, p.T143Nfs*5), WDR62 (c.3406C>T, p.R1136*), ASPM (c.5219&#95;5225delGAGGATA, p.R1740Tfs*7), RARS (c.1588A>G, p.T530A), CC2D1A (c.811delG, p.A271Pfs*30), TUSC3 (c.793C>T, p.Q265*) and ZNF335 (c.808C>T, p.R270C and c.3715C>A, p.Q1239K) previously linked with ARID. Besides ARID genes, in one family, affected male siblings were hemizygous for PQBP1 (c.459&#95;462delAGAG, p.R153Sfs*41) and in one family the proband was female and heterozygous for X-chromosomal SLC9A6 (c.1631+1G>A) variant. Each of these variants, except for those in MCPH1 and PQBP1, have not been previously published. Additionally in one family, two affected children were homozygous for the c.377G>A (p.W126*) variant in the FAM183A, a gene not previously associated with ARID. No causative variants were found in the remaining 11 families. A wide variety of variants explain half of families with ARID. FAM183A is a promising novel candidate gene for ARID., Competing Interests: The authors have declared that no competing interests exist.

Objective: To assess the efficacy and safety of a new surgical suture technique for uterine preservation among patients with placental invasion anomalies., Methods: The present prospective case series included women diagnosed with placental invasion anomalies undergoing cesarean deliveries who desired future fertility at the obstetrics department of a Turkish university hospital between January 10, 2013, and April 20, 2017. Patients were diagnosed with ultrasonography and Doppler ultrasonography; the type of placental invasion anomaly (placenta accreta, increta, or percreta) was confirmed intraoperatively. Surgical management involved an intracavitary suture technique after the proximal branch of the uterine artery was clamped and utero-ovarian anastomoses had been blocked. Outcomes included units of blood transfused, intraoperative and postoperative adverse events, duration of hospital admission, and hysterectomy rate., Results: There were 62 patients included. The mean operative blood loss was 1350 ± 750 mL (range 600-5000 mL). Blood transfusion required a mean of four units (range 2-15). Bleeding was controlled with the intracavitary sutures in 58 (94%) patients. Three patients experienced postoperative wound infections and two patients developed endometritis that required therapy with broad-spectrum antibiotics. The mean length of hospital stay was 3.6 ± 1.6 days (range 2-11). None of the patients required reoperation after the initial surgery., Conclusion: The novel uterus-sparing suture technique was highly effective among patients with placental invasion anomalies., (© 2018 International Federation of Gynecology and Obstetrics.)

In nature, adaptive coloration has been effectively utilized for concealment and signaling. Various biological mechanisms have evolved to tune the reflectivity for visible and ultraviolet light. These examples inspire many artificial systems for mimicking adaptive coloration to match the visual appearance to their surroundings. Thermal camouflage, however, has been an outstanding challenge which requires an ability to control the emitted thermal radiation from the surface. Here we report a new class of active thermal surfaces capable of efficient real-time electrical-control of thermal emission over the full infrared (IR) spectrum without changing the temperature of the surface. Our approach relies on electro-modulation of IR absorptivity and emissivity of multilayer graphene via reversible intercalation of nonvolatile ionic liquids. The demonstrated devices are light (30 g/m 2 ), thin (<50 μm), and ultraflexible, which can conformably coat their environment. In addition, by combining active thermal surfaces with a feedback mechanism, we demonstrate realization of an adaptive thermal camouflage system which can reconfigure its thermal appearance and blend itself with the varying thermal background in a few seconds. Furthermore, we show that these devices can disguise hot objects as cold and cold ones as hot in a thermal imaging system. We anticipate that, the electrical control of thermal radiation would impact on a variety of new technologies ranging from adaptive IR optics to heat management for outer space applications.

Purpose: To assess the levels of retinal and choroidal involvement in initial-onset birdshot retinochoroiditis (BRC) and Vogt-Koyanagi-Harada (VKH) disease, two stromal choroiditis entities., Methods: This retrospective study included patients diagnosed with BRC and VKH, seen during initial-onset disease at the Centre for Ophthalmic Specialized Care, Lausanne, Switzerland. Angiographic signs were quantified, using an established dual fluorescein angiography (FA) and indocyanine green angiography (ICGA) scoring system for uveitis, and the FA/ICGA score ratios were compared between diseases., Results: Among 1793 patients with uveitis seen from 1995 to 2015, 7 newly diagnosed BRC patients and 4 patients with newly diagnosed VKH disease had sufficient data for study inclusion. Patients with BRC and VKH at initial onset had mean FA angiographic scores of 16.91 ± 3.42 and 4.06 ± 1.87; mean ICGA angiographic scores of 21.34 ± 3.49 and 25.75 ± 3.88; and mean FA/ICGA ratios of 0.79 ± 0.21 and 0.16 ± 0.09, respectively., Conclusion: This study showed the differential involvements of the retina and choroid in BRC and VKH. The choroid was preponderantly involved in both diseases; thus, ICGA is essential for disease assessment and follow-up. However, these diseases also differed substantially. The origin of inflammation was primarily in the choroid in VKH and in both the choroid and retina in BRC. We recommend dual FA and ICGA for evaluating posterior uveitis, when choroiditis is suspected.

Metamaterials bring subwavelength resonating structures together to overcome the limitations of conventional materials. The realization of active metadevices has been an outstanding challenge that requires electrically reconfigurable components operating over a broad spectrum with a wide dynamic range. However, the existing capability of metamaterials is not sufficient to realize this goal. By integrating passive metamaterials with active graphene devices, we demonstrate a new class of electrically controlled active metadevices working in microwave frequencies. The fabricated active metadevices enable efficient control of both amplitude (>50 dB) and phase (>90°) of electromagnetic waves. In this hybrid system, graphene operates as a tunable Drude metal that controls the radiation of the passive metamaterials. Furthermore, by integrating individually addressable arrays of metadevices, we demonstrate a new class of spatially varying digital metasurfaces where the local dielectric constant can be reconfigured with applied bias voltages. In addition, we reconfigure resonance frequency of split-ring resonators without changing its amplitude by damping one of the two coupled metasurfaces via graphene. Our approach is general enough to implement various metamaterial systems that could yield new applications ranging from electrically switchable cloaking devices to adaptive camouflage systems.

Background: The aim was to evaluate the clinical efficacy of topical azithromycin 1.5 per cent ophthalmic solution in treatment of the clinical signs and symptoms associated with meibomian gland dysfunction (MGD)., Methods: In this retrospective study, 35 patients with MGD were treated with topical azithromycin 1.5 per cent ophthalmic solution for 30 days. Topical azithromycin 1.5 per cent ophthalmic solution was prescribed twice daily for two days and then once daily for a total of 30 days. Daily lid hygiene with dilute baby shampoo was instructed for all patients. Patient total symptom score, meibomian gland grading score, Schirmer score with anaesthetic, tear film break-up time (TFBUT) and corneal fluorescein staining score were evaluated at baseline and after one and three months., Results: Patient total symptom score, meibomian gland grading score, Schirmer score with anaesthetic, TFBUT and corneal staining score reduced significantly from the baseline to the first month (p < 0.05, for each); however, at the third month, there was no significant difference from baseline in the meibomian gland grading score, Schirmer score with anaesthetic, TFBUT and corneal fluorescein staining score (p > 0.05, for each)., Conclusion: These results demonstrate that topical azithromycin 1.5 per cent ophthalmic solution appears effective in the short-term treatment of the clinical signs and symptoms associated with MGD., (© 2017 Optometry Australia.)

Purpose: To investigate the longitudinal change in intraocular pressure (IOP) in premature infants and to establish a normative IOP value., Methods: Forty premature infants with a gestational age (GA) of 26 weeks were enrolled in this longitudinal study. Measurements were taken initially at 28 weeks postconceptional age (PCA) and at 2-week intervals up to 40 weeks PCA. Intraocular pressure was measured with a hand-held tonometer (Tono-Pen XL; Reichert Inc.)., Results: From 40 (22 male, 18 female) premature Caucasian infants, seven (for each eye) IOP measurements were obtained. Mean GA was 26 weeks and mean birthweight was 820 ± 112 grams. The mean IOP was 15.1 ± 1.2 mm Hg and 14.9 ± 1.1 mm Hg for the right and left eyes, respectively. The mean IOP in both eyes for all measurements was 15.0 ± 1.1 mm Hg. At 28 weeks PCA, 9 (22.5%) preterm infants had IOP values greater than 20 mm Hg. The mean IOPs at 28 weeks, 30 weeks, 32 weeks, 34 weeks, 36 weeks, 38 weeks, and 40 weeks PCA were 18.7 ± 1.1 mm Hg, 16.9 ± 0.9 mm Hg, 15.3 ± 0.9 mm Hg, 14.1 ± 1.3 mm Hg, 13.7 ± 1.3 mm Hg, 13.4 ± 1.4 mm Hg, and 13.1 ± 1.3 mm Hg, respectively. A significant decrease in IOP measurements was found up to 34 weeks PCA, with no significant decline in IOP measurements after that point (F = 109.7, p<0.01). There was a negative correlation between IOP and PCA (r = -0.712, p<0.01)., Conclusions: The mean IOP of premature infants was 15.0 ± 1.1 mm Hg and IOP values decreased significantly up to 34 weeks PCA, indicating a decline trend approaching the term period.

The purpose of this study is to investigate the performance, utility, and precision of enhanced depth imaging optical coherence tomography (EDI-OCT) versus indocyanine green angiography (ICGA) in tracking any fluctuation in the activity of stromal choroiditis in response to therapeutic interventions during long-term follow-up. Patients with a diagnosis of Vogt-Koyanagi-Harada (VKH) disease or birdshot retinochoroiditis (BRC), with untreated initial disease, and having had long-term follow-up, including both ICGA and EDI-OCT, were recruited at the Centre for Ophthalmic Specialised care, Lausanne, Switzerland. Angiography signs were quantified according to established dual fluorescein angiography (FA) and ICGA scoring systems for uveitis. Changes in ICGA score and EDI choroidal thickness, in response to therapeutic intervention, were assessed. In the four eyes analysed (2 BRC and 2 VKH), mean EDI-OCT choroidal thickness decreased from 672 ± 101 µm at presentation to 358.5 ± 44.5 µm in a mean of 26.5 months, i.e. the time taken to stabilize the disease. Mean ICGA scores decreased from 28 ± 4.2 at presentation to 5 ± 7 at stabilization. Only ICGA was sufficiently sensitive and reactive having the ability to detect disease recurrences and efficacy or the absence of effect of successive treatment changes, detected in seven instances during follow-up, not recorded by EDI-OCT. This pilot study showed that ICGA was a more sensitive methodology, which promptly identifies evolving subclinical and occult choroidal disease, and flag occult recurrence and/or therapeutic responses that were otherwise missed by EDI-OCT. Although choroidal thickness was proportional to treatment course, demonstrating a linear decrease, these changes were too sluggish to be relied upon for close follow-up and timely adjustment of therapy.

The objective of the study was to compare the success rate of transcanalicular laser dacryocystorhinostomy (TCL-DCR) with or without the use of adjunctive mitomycin C (MMC) in cases with primary nasolacrimal duct obstruction (NLDO). This retrospective study was comprised of 68 patients with uncomplicated primary NLDO. There were two groups in the study: the Group 1 (n = 35) patients underwent TCL-DCR surgery with MMC and the Group 2 (n = 33) patients underwent TCL-DCR surgery without MMC. All patients had bicanalicular silicone tube intubation. The main outcome measures were patent osteotomy as visualized endoscopically and patent nasolacrimal irrigation. The follow-up period was 12 months. All patients had unilateral TCL-DCR with silicone tube intubation. Six months following surgery, the silicone tubes were removed. At the final evaluation, success rates were 80 % in Group 1 and 78.8 % in Group 2. There was no statistically significant difference between the two groups (p = 0.52). No complications related to MMC usage were recorded during the study period. Intraoperative use of MMC has no beneficial effect on the success rate in TCL-DCR.

Objective: The association between arterial ischemic stroke (AIS) and celiac disease (CD) has been described in only a few cases in adults and children. We aim to determine the prevalence of CD in children and adolescents with AIS., Study Design: We investigated serum levels of tissue transglutaminase antibody immunoglobulin (Ig)A and total IgA from 76 children with AIS and in a healthy control group of 102 children. Study participants who were positive for tissue transglutaminase IgA antibodies underwent a duodenal biopsy., Results: A total of 2 patients in the AIS group (2.26%) and 2 in the control group (1.96%) had positive serum tissue transglutaminase antibody (P=0.89; 95% confidence interval, -5.05 to 6.89). Duodenal biopsy confirmed CD in only 1 patient who had AIS., Conclusions: In the present study, children with acute arterial stroke did not exhibit a higher prevalence rate of CD compared with healthy controls. Therefore, the screening test for CD is not a necessary part of the management of AIS in children. However, cases of recurrent AIS could be examined for CD.

We report reversible and spectrally selective fluorescence quenching of quantum dots (QDs) placed in close proximity to graphene. Controlling interband electronic transitions of graphene via electrostatic gating greatly modifies the fluorescence lifetime and intensity of nearby QDs via blocking of the nonradiative energy transfer between QDs and graphene. Using ionic liquid (IL) based electrolyte gating, we are able to control Fermi energy of graphene in the order of 1 eV, which yields electrically controllable fluorescence quenching of QDs in the visible spectrum. Indeed, our technique enables us to perform voltage controllable spectral selectivity among quantum dots at different emission wavelengths. We anticipate that our technique will provide tunable light-matter interaction and energy transfer that could yield hybrid QDs-graphene based optoelectronic devices with novel functionalities, and additionally, may be useful as a spectroscopic ruler, for example, in bioimaging and biomolecular sensing. We propose that graphene can be used as an electrically tunable and wavelength selective fluorescence quencher.