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A modification of the variational iteration method (VIM) for solving systems of nonlinear fractional-order differential equations is proposed. The fractional derivatives are described in the Caputo sense. The solutions of fractional differential equations (FDE) obtained using the traditional variational iteration method give good approximations in the neighborhood of the initial position. The main advantage of the present method is that it can accelerate the convergence of the iterative approximate solutions relative to the approximate solutions obtained using the traditional variational iteration method. Illustrative examples are presented to show the validity of this modification.

IntroductionCurrent treatment strategies for primary upper extremity deep venous thrombosis (pUEDVT) range from conservative treatment with anticoagulation therapy to invasive treatment with thoracic outlet decompression surgery (TOD), frequently combined with catheter directed thrombolysis, percutaneous transluminal angioplasty, or stenting. Due to a lack of large prospective series with uniform data collection or a randomized trial, the optimal treatment strategy is still under debate. We conducted a multicenter observational study to assess the efficacy and safety of both the conservative and invasive treatment strategies for patients with pUEDVT.MethodsWe retrospectively collected data from patients treated in five vascular referral and teaching hospitals in the Netherlands between 2008 and 2019. Patients were divided into a conservative (Group 1), an invasive treatment group (Group 2) and a cross-over group (Group 3) of patients who received surgical treatment after initial conservative therapy. Follow-up consisted of outpatient clinic visits and an electronic survey. Primary outcome was symptom free survival defined as absence of any symptom of the affected arm reported at last follow-up regardless of severity, or extent of functional disability. Secondary outcomes were incidence of bleeding complications, recurrent venous thromboembolism, surgical complications, and reinterventions.ResultsA total of 115 patients were included (group 1 (N = 45), group 2 (N = 53) or group 3 (N = 27). The symptom free survival was 35.6%, 54.7% and 48.1% after a median follow-up of 36, 26 and 22 months in groups 1, 2 and 3 respectively. Incidence of bleeding complications was 8.6%, 3.8% and 18.5% and recurrent thrombosis occurred in 15.6%, 13.2% and 14.8% in groups 1–3 respectively.ConclusionIn this multicenter retrospective observational cohort analysis the conservative and direct invasive treatments for pUEDVT were deemed safe with low percentages of bleeding complications. Symptom free survival was highest in the direct surgical treatment group but still modest in all subgroups. Perioperative complications were infrequent with no related long term morbidity. Of relevance, pUEDVT patients with confirmed VTOS and recurrent symptoms after conservative treatment may still benefit from TOD surgery. However, symptom free survival of this delayed TOD seems lower than direct surgical treatment and bleeding complications seem to occur more frequently.

IntroductionStrict imaging surveillance protocols to detect complications following endovascular aneurysm repair (EVAR) are common practice. However, controversy exists as to whether all EVAR patients need intense surveillance. The 2019 European Society for Vascular Surgery guidelines for management of abdominal aortic aneurysm (AAA) suggest that patients may be considered for limited follow-up with imaging if classified as ‘low risk’ for complications based on their initial postoperative imaging. The current study aims to investigate the intervention-free survival and overall survival stratified for patients with and without yearly imaging surveillance.Methods and analysisThe Observing a Decade of Yearly Standardised Surveillance in EVAR patients with Ultrasound or CT Scan study comprises a national multicentre retrospective cohort study in 17 medical centres. Consecutive patients with an asymptomatic or symptomatic infrarenal AAA who underwent EVAR between January 2007 and January 2012 will be included in this study with follow-up until December 2018. Clinical variables and all follow-up information will be retrieved in extensive data collection from the patient’s medical records. In addition, an e-survey was sent to vascular surgeons at the 17 participating centres to gauge their opinions regarding the possibility of safely reducing the frequency of imaging surveillance. Primary endpoints are intervention after EVAR and aneurysm-related mortality. The initial estimated sample size is 1997 patients.Ethics and disseminationThe study has been approved by the Medical Ethics Review Committee of the Amsterdam UMC, location Academic Medical Centre, Amsterdam, the Netherlands. Study findings will be disseminated via presentations at conferences and publications in peer-reviewed journal.Trial registration numberThe Netherlands Trial Registry, NL6953 (old: NTR28773).

Water soluble Zn based quantum dots (QDs) are of interest due to their biocompatibility and less toxic features. They have been frequently used in studies related to biotechnology, especially in agriculture studies. However, to control the optical properties of Zn based QDs has still been a challenge. In this work, the defect state emission of ZnSe QDs was successfully controlled through two different routes; 1) By creating a sulfur rich outer region around the Se rich core 2) By changing the capping agent. Gradient alloyed ZnSeS QDs with Se rich core and S rich outer region were successfully synthesized with two different capping agents; N-Acetyl-L-Cysteine (NAC) and 3-Mercaptopropionic Acid (3-MPA). The contribution of emission originated from surface-defects almost disappeared in NAC capped ZnSeS QDs, with causing a significant increase in photoluminescence quantum yield. The interaction between Zn based QDs with chlorophyll molecules was also investigated. The absorption capacity of chlorophylls significantly enhanced upon interaction with 3-MPA capped ZnSeS QDs. Also, the spectral response of chlorophylls could be modulated through interaction with 3-MPA capped ZnSeS QDs, which could be manipulated by using ZnSeS QDs with different chemical composition. Our results indicated that ZnSeS QDs have potential to be used in agriculture, which could act as a modulator of light-harvesting capacity of chlorophylls. The ability to modulate chlorophyll spectral responses through QD interaction opens new possibilities for optimizing light utilization in photosynthetic organisms, thereby contributing to enhanced crop yields and more efficient use of light energy in natural and artificial ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Photosynthesis relies on the absorption of sunlight by photosynthetic pigments (PPs) such as chlorophylls and carotenoids. While these pigments are outstanding at harvesting light, their natural structure restricts their ability to harvest light at specific wavelengths. In this study, Oleic acid-capped CdSeS and CdTeS ternary quantum dots (QDs) were synthesized using a novel two-phase synthesis method. Then, these QDs were used to interact with raw PPs, a mixture of chlorophylls and carotenoids isolated from spinach. Our findings revealed the following: (1) Interacting QDs with raw PPs effectively inhibited the chlorophyll fluorescence of the pigments upon excitation in UV light region (250-400 nm) without causing any damage to their structure. (2) By forming an interaction with QDs, the chlorophyll fluorescence of raw PPs could be induced through excitation with green-light spectrum. (3) The composition of the QDs played a fundamental role in their interaction with PPs. Our study demonstrated that the photophysical properties of isolated PPs could be modified by using cadmium-based QDs by preserving the structure of the pigments themselves., (© 2024. The Author(s).)

Biomaterial-mediated bone tissue engineering (BTE) offers an alternative, interesting approach for the restoration of damaged bone tissues in postsurgery osteosarcoma treatment. This study focused on synthesizing innovative composite inks, integrating self-assembled silk fibroin (SF), tannic acids (TA), and electrospun bioactive glass nanofibers 70SiO 2 -25CaO-5P 2 O 5 (BGNF). By synergistically combining the unique characteristics of these three components through self-assembly and microextrusion-based three-dimensional (3D) printing, our goal was to produce durable and versatile aerogel-based 3D composite scaffolds. These scaffolds were designed to exhibit hierarchical porosity along with antibacterial, antiosteosarcoma, and bone regeneration properties. Taking inspiration from mussel foot protein attachment chemistry involving the coordination of dihydroxyphenylalanine (DOPA) amino acids with ferric ions (Fe 3+ ), we synthesized a tris-complex catecholate-iron self-assembled composite gel. This gel formation occurred through the coordination of oxidized SF (SFO) with TA and polydopamine-modified BGNF (BGNF-PDA). The dynamic nature of the coordination ligand-metal bonds within the self-assembled SFO matrix provided excellent shear-thinning properties, allowing the SFO-TA-BGNF complex gel to be extruded through a nozzle, facilitating 3D printing into scaffolds with outstanding shape fidelity. Moreover, the developed composite aerogels exhibited multifaceted features, including NIR-triggered photothermal antibacterial and in vitro photothermal antiosteosarcoma properties. In vitro studies showcased their excellent biocompatibility and osteogenic features as seeded cells successfully differentiated into osteoblasts, promoting bone regeneration in 21 days. Through comprehensive characterizations and biological validations, our antibacterial scaffold demonstrated promise as an exceptional platform for concurrent bone regeneration and bone cancer therapy, setting the stage for their potential clinical application.

Whitish-blue light emitting fluorescent ZIF-8 structures were synthesized by means of bis-carboxylate functional calix[4]pyrrole (BCCP) modification. The calix[4]pyrrole concentration was also manipulated to tune the sizes of the ZIF-8 structures. Moreover, the BCCP-modified ZIF-8 samples exhibited enhanced organic micropollutant removal capacity from aqueous solutions.

Cadmium-based quantum dots (QDs) are amongst the most studied nanomaterials due to their excellent photophysical properties, which can be controlled by controlling the size and/or composition of the nanocrystal. However, the ultraprecise control over size and photophysical properties of Cd-based quantum dots and developing user-friendly techniques to synthesize amino acid-functionalized cadmium-based QDs are still the on-going challenges. In this study, we modified a traditional two-phase synthesis method to synthesize cadmium telluride sulfide (CdTeS) QDs. CdTeS QDs were grown with an extremely slow growth-rate (growth saturation of about 3 days), which allowed us to have an ultraprecise control over size, and as a consequence, the photophysical properties. Also, the composition of CdTeS could be controlled by controlling the precursor ratios. The CdTeS QDs were successfully functionalized with a water-soluble amino acid, L-cysteine, and an amino acid derivative, N -acetyl-L-cysteine. Red-emissive L-cysteine-functionalized CdTeS QDs interacted with yellow-emissive carbon dots. The fluorescence intensity of carbon dots increased upon interaction with CdTeS QDs. This study proposes a mild method that allows to grow QDs with an ultraprecise control over the photophysical properties and shows the implementation of Cd-based QDs to enhance the fluorescence intensity of different fluorophores with fluorescence wavelength at higher energy bands.

We report on time-dependent density functional theory calculations of the excited states of 63 different graphene quantum dots (GQDs) in square shape with side lengths of 1, 1.5, and 2 nm. We investigate the systematics and trends in the UV-vis absorption spectra of these GQDs, which are doped with elements B, N, O, S, and P at dopant percentages of 1.5%, 3%, 5%, and 7%. The results show how the peaks in the UV and visible parts of the spectrum as well as the total absorption evolve in the chemical parameter space along the coordinates of size, dopant type, and dopant percentage. The absorption spectra calculated here can be used to obtain particular GQD mixture proportions that would yield a desired absorption profile such as flat absorption across the whole visible spectrum or one that is locally peaked around a chosen wavelength., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Carbon dots (CDs) are versatile fluorescent nanocrystals with unique optical and structural properties and are commonly used in biosensing, bioimaging, and biomolecule tagging studies. However, fluorescence of CDs is brightest in the wavelength range of 430-530 nm, which overlaps with the autofluorescence range of many eukaryotic cells and makes CDs impractical for in vivo and in vitro imaging studies. Thus, the design of yellow-red emissive CDs with high quantum yield is of importance. In this study, the quantum yield of traditional yellow emissive CDs was enhanced by two different methods: (1) the surface of traditional yellow emissive CDs passivated with a biomolecule, urea, through easy, rapid, inexpensive microwave assisted synthesis methods and (2) a fluorescent biomolecule, aflatoxin B1, used as an energy donor for yellow emissive CDs. In the first method, the quantum yield of the CDs was enhanced to 51%. In the second method, an efficient energy transfer (above 40%) from aflatoxin B1 to the CDs was observed. Our study showed that highly luminescent yellow emissive CDs can be synthesized by simple, rapid microwave assisted synthesis methods, and these CDs are potential candidates to sense aflatoxin B1. Furthermore, our results indicated that Aflatoxin B1 can be considered as an emission booster for CDs., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Carbon dots (CDs) are carbon-based fluorescent nanomaterials that are of interest in different research areas due to their low cost production and low toxicity. Considering their unique photophysical properties, hydrophobic/amphiphilic CDs are powerful alternatives to metal-based quantum dots in LED and photovoltaic cell designs. On the other hand, CDs possess a considerably high amount of surface defects that give rise to two significant drawbacks: (1) causing decrease in quantum yield (QY), a crucial drawback that limits their utilization in LEDs, and (2) affecting the efficiency of charge transfer, a significant factor that limits the use of CDs in photovoltaic cells. In this study, we synthesized highly luminescent, water-insoluble, slightly amphiphilic CDs by using a macrocyclic compound, calix[4]pyrrole, for the first time in the literature. Calix[4]pyrrole-derived CDs (CP-DOTs) were highly luminescent with a QY of over 60% and size of around 4-10 nm with graphitic structure. The high quantum yield of CP-DOTs indicated that they had less amount of surface defects. Furthermore, CP-DOTs were used as an additive in the active layer of organic solar cells (OSC). The photovoltaic parameters of OSCs improved upon addition of CDs. Our results indicated that calix[4]pyrrole is an excellent carbon precursor to synthesize highly luminescent and water-insoluble carbon dots, and CDs derived from calix[4]pyrrole are excellent candidates to improve optoelectronic devices., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Quantum dots are versatile fluorescent semiconductor nanocrystals with unique photophysical properties. They have been used in various research fields of biotechnology effectively for almost three decades including cell imaging, protein tracking, energy transfer, etc. With their great potential as energy donors or acceptors, quantum dots have also been used in many studies about altering growth rate and photosynthetic activity of photosynthetic organisms by manipulating their light harvesting capacity. In this review, effect of quantum dots on growth rate of photosynthetic organisms and light harvesting capacity of photosynthetic organisms were discussed in details together with toxic effects of cadmium-based and carbon-based quantum dots on photosynthetic organisms. In short, as one of the promising materials of nanotechnology, quantum dots have become one of the essential research topics in photosynthesis research area and will help researchers to manipulate natural photosynthesis in future.

Quantum dots (QDs) are significant fluorescent materials for energy transfer studies with phthalocyanines (Pcs) and phthalocyanine (Pc)-like biomolecules (such as chlorophylls). Carbon-based QDs, especially, have been used in numerous studies concerning energy transfer with chlorophylls, but the numbers of studies concerning energy transfer between phthalocyanines and carbon-based QDs are limited. In this study, peripherally, hydroxythioethyl terminal group substituted metal-free phthalocyanine (H 2 Pc) and zinc phthalocyanine (ZnPc) were noncovalently (electrostatic and/or π-π interaction) attached to carbon QDs containing boron and nitrogen to form QD-Pc nanoconjugates. The QD-Pc conjugates were characterized using different spectroscopic techniques (Fourier transform infrared spectroscopy and transmission electron microscopy). The absorption and fluorescence properties of QD-Pc structures in solution were studied. It was found that the quantum yields of the QDs slightly decreased from 30% to 25% upon doping the QDs with heteroatoms B and N. Förster resonance energy transfer efficiency was calculated as 33% for BCN-QD/ZnPc. For the other conjugates, almost no energy transfer from QDs to Pc cores was observed. It was shown that the energy transfer between QDs to Pc cores was completely different from the energy transfer between QDs and photosynthetic pigments, and therefore we concluded that heteroatom doping in the QD structure and the existence of zinc metal in the phthalocyanine structure is obligatory for an efficient energy transfer., (© 2021 John Wiley & Sons Ltd.)

One of the major challenges in modern robotics is controlling micromanipulation by active and adaptive materials. In the respiratory system, such actuation enables pathogen clearance by means of motile cilia. While various types of artificial cilia have been engineered recently, they often involve complex manufacturing protocols and focus on transporting liquids only. Here, soft magnetic carpets are created via an easy self-assembly route based on the Rosensweig instability. These carpets can transport not only liquids but also solid objects that are larger and heavier than the artificial cilia, using a crowd-surfing effect.This amphibious transportation is locally and reconfigurably tunable by simple micromagnets or advanced programmable magnetic fields with a high degree of spatial resolution. Two surprising cargo reversal effects are identified and modeled due to collective ciliary motion and nontrivial elastohydrodynamics. While the active carpets are generally applicable to integrated control systems for transport, mixing, and sorting, these effects can also be exploited for microfluidic viscosimetry and elastometry., (© 2021 The Authors. Advanced Science published by Wiley-VCH GmbH.)

CdSe quantum dots are the most studied Cd-based quantum dots with their high quantum yield, high photostability, narrow emission band, and easy synthesis procedure. They are frequently used to develop light emitting diode (LED) due to their unique photophysical properties; however, their narrow emission band causes a challenge to design white LEDs because white light emission requires emission in multiple wavelengths with broad emission bands. Here in this study, we developed CdSe quantum dots with a narrow band-edge emission band and broad defect-state emission band through a modified two-phase synthesis method. Our results revealed that defect-state emission is directly linked to the surface of quantum dots and can be excited through exciting surfactant around the quantum dot. The effect of surfactant on emission properties of CdSe quantum dots diminished upon growing a shell around CdSe quantum dots; as a result, surface-dependent defect-state emission cannot be observed in gradient heterogeneous alloyed CdS x Se 1-x quantum dots., Competing Interests: CONFLICT OF INTEREST: none declared, (Copyright © 2021 The Author(s).)

Quantum dots (QDs) are synthetic semiconductor nanocrystals with unique optical and electronic properties due to their size (2-10 nm) such as high molar absorption coefficient (10-100 times higher than organic dyes), resistance to chemical degradation, and unique optoelectronic properties due to quantum confinement (high quantum yield, emission color change with size). Compared to organic fluorophores, the narrower emission band and wider absorption bands of QDs offer great advantages in cell imaging and biosensor applications. The optoelectronic features of QDs have prompted their intensive use in bioanalytical, biophysical, and biomedical research. As the nanomaterials have been integrated into microfluidic systems, microfluidic technology has accelerated the adaptation of nanomaterials to clinical evaluation together with the advantages such as being more economical, more reproducible, and more susceptible to modification and integration with other technologies. Microfluidic systems serve an important role by being a platform in which QDs are integrated for biosensing applications. As we combine the advantages of QDs and microfluidic technology for biosensing technology, QD-based biosensor integrated with microfluidic systems can be used as an advanced and versatile diagnostic technology in case of pandemic. Specifically, there is an urgent necessity to have reliable and fast detection systems for COVID-19 virus. In this review, affinity-based biosensing mechanisms which are developed with QDs are examined in the domain of microfluidic approach. The combination of microfluidic technology and QD-based affinity biosensors are presented with examples in order to develop a better technological framework of diagnostic for COVID-19 virus., (© Qatar University and Springer Nature Switzerland AG 2021.)

Light harvesting in photosynthesis is currently an issue on-debate and studied widely in all over the world. Studies on light harvesting mainly focus on enlightening molecular mechanism of the process and enhancing absorption capacity of light harvesting complexes (LHCs). Enhancement of absorption capacity of LHCs can be done either by natural methods or by synthetic methods. Quantum dots (QDs), fluorescent semiconductor nanocrystals, are important constituents of inorganic-organic hybrid structures which are built to enhance absorption capacity of LHCs through synthetic methods. In this study, we synthesized carbon and heteroatom doped carbon QDs through a microwave assisted synthesis method. Each QD had unique photophysical and structural properties. Photosynthetic pigments (PP) (isolated from spinach leaves) were mixed with each QD separately to build a QD-PP hybrid structure. Our results revealed that significant amount of energy is transferred from carbon QDs to PPs and therefore chlorophyll fluorescence capacity of PPs enhanced significantly in 360-420 nm excitation wavelength interval. Our results suggested that non-toxic, inexpensive and easily synthesized carbon QDs can be an important constituent for hybrid structures to enhance absorption capacity of LHCs in highly energetic region of visible spectrum.

Objective: To investigate whether prior testis magnetic resonance spectroscopy predicts the success or failure of micro-dissection testicular sperm extraction (micro-TESE) in patients with non-obstructive azoospermia (NOA)., Material and Methods: Nine men with NOA who were scheduled for micro-TESE for the first time, 9 NOA men with a history of previous micro-TESE and 5 fertile men were enrolled. All NOA patients and fertile controls underwent testis spectroscopy. A multi-voxel spectroscopy sequence was used. Testicular signals of choline (Cho), creatine (Cr), myo-inositol (MI), lactate, and lipids were analyzed quantitatively and compared with the results of the micro-TESEs., Results: The most prominent peaks were Cho and Cr in the fertile controls and NOA subjects with positive sperm retrieval in the micro-TESE. A high Cho peak was detected in 87% of the NOA men with positive sperm retrieval. NOA men without sperm at the previous micro-TESE showed a marked decrease in Cho and Cr signals. For positive sperm retrieval in micro-TESE, the cut-off value of Cho was 1.46 ppm, the cut-off value of Cr was 1.43 ppm, and the cut-off value of MI was 0.79 ppm., Conclusion: Testis spectroscopy can be used as a non-invasive screening method to predict the success or failure of micro-TESE.

As the reproductive technology advanced along with the improved outcome in cancer treatment demands implementing new fertility preservation, developing algorithms on fertility preservation requires tailoring for each society. Here, the authors attempt to modify the current medical literature on fertility preservation for the Turkish population. A PubMed search was conducted using the search term fertility preservation . Initially, 280 items of literature were accessed. In the second evaluation, 126 articles were examined and 154 items were discarded due to the low quality of the literature. In the final round, only 68 publications that were the most relevant were found eligible for inclusion in this review article. In order to develop a more systematic national guideline, forming a multidisciplinary approach to create a web-based network would be the first step. Both physicians and patients will have open access to the information. This database should be linked to an international consortium to stay integrated and open for updating. The aim of this review was to evaluate the relationship between the current situation in our country and the developments in the world in light of the literature, and to establish infrastructure for the development of future approaches in our country.

Purpose: We aimed to investigate whether the accuracy of the Plusoptix A09 photorefractor in children with ametropia is enhanced by cycloplegia with 1% tropicamide., Methods: A total of 70 eyes (70 children) were retrospectively reviewed. Noncycloplegic photorefraction, cycloplegia with 1% tropicamide, cycloplegic photorefraction, and cycloplegic refraction with a tabletop autorefractometer were performed on all subjects in this order. Measurements were compared statistically., Results: The mean age was 45.9 ± 11.4 months. The mean spherical equivalent (0.61 ± 1.03 diopters (D); range, -2.38 to 3.63 D) and mean spherical power (1.16 ± 0.92 D; range, -1.25 to 3.75 D) values that were acquired from the photorefraction without cycloplegia showed statistically significant differences from those of the autorefraction with cycloplegia (mean spherical equivalent = 1.00 ± 1.27 D; range, -1.50 to 4.25 D, mean spherical power = 1.60 ± 1.14; range, -1.25 to 4.50 D). The mean difference for the spherical equivalent was -0.39 ± 0.93 D ( P =0.021; 95% limits of agreement (LoA) = -2.22 D to 1.44 D) and for spherical power was -0.44 ± 1.02 D ( P =0.016; LoA = -2.44 D to 1.56 D). Without cycloplegia, Plusoptix A09 showed myopic shift, while after cycloplegia, it showed hyperopic shift. Spherical equivalent (mean difference (MD) ± SD = 0.78 ± 1.00 D, P < 0.001; LoA = -1.17 D to 2.72 D) and spherical power (MD ± SD = 0.73 ± 1.04 D, P < 0.001; LoA = -1.31 D to 2.77 D) values were significantly different from those of autorefraction with cycloplegia. Cylindrical power values obtained by photorefraction both with and without cycloplegia were not statistically different from those of autorefraction with cycloplegia ( P > 0.05)., Conclusion: Cycloplegia with 1% tropicamide did not improve the accuracy of photorefraction using Plusoptix A09 in preschool children. The spherical equivalent and spherical power values obtained by photorefraction with cycloplegia were significantly higher from those obtained by autorefraction with cycloplegia.

Purpose: We aimed to investigate whether anterior chamber angle, depth, and volume change after myopic laser-assisted in situ keratomileusis (LASIK) in young patients., Methods: This retrospective study included 29 eyes of 29 patients (15 females and 14 males) between the ages of 18 and 39 years who underwent LASIK for the treatment of myopia. In addition to complete ophthalmic examination, anterior chamber angle (ACA), central anterior chamber depth (ACD), and anterior chamber volume (ACV) were measured by using a Sirius rotating Scheimpflug camera combined with Placido disc corneal topography (CSO, Florence, Italy). Preoperative and postoperative values were compared using paired t- tests. Linear regression was used to evaluate the relationship between changes in refraction and changes in ACA, ACD, and ACV as well as between attempted maximum ablation depth and changes in ACA, ACD, and ACV., Results: The mean age of the study population was 25.5 ± 6.2 years. The mean preoperative and postoperative spherical equivalent values were -3.30 ± 1.92 D and -0.18 ± 0.29 D, respectively. ACV and ACA were not significantly changed after surgery; however, central ACD was significantly decreased (preoperatively = 3.366 ± 0.316 mm vs postoperatively = 3.3 ± 0.298 mm) with a mean difference of 0.066 ± 1.121 mm. There were no significant relationships between changes in refraction and anterior segment dimensions or between attempted maximum ablation depth and anterior segment dimensions., Conclusion: Measurements with Sirius showed that ACA and ACV did not change; however, central ACD significantly decreased after myopic LASIK in young patients, indicating that the preoperative central ACD value should not be used interchangeably with the postoperative central ACD value.

The bioenergetics of light-harvesting by photosynthetic antenna proteins in higher plants is well understood. However, investigation into the regulatory non-photochemical quenching (NPQ) mechanism, which dissipates excess energy in high light, has led to several conflicting models. It is generally accepted that the major photosystem II antenna protein, LHCII, is the site of NPQ, although the minor antenna complexes (CP24/26/29) are also proposed as alternative/additional NPQ sites. LHCII crystals were shown to exhibit the short excitation lifetime and several spectral signatures of the quenched state. Subsequent structure-based models showed that this quenching could be explained by slow energy trapping by the carotenoids, in line with one of the proposed models. Using Fluorescence Lifetime Imaging Microscopy (FLIM) we show that the crystal structure of CP29 corresponds to a strongly quenched conformation. Using a structure-based theoretical model we show that this quenching may be explained by the same slow, carotenoid-mediated quenching mechanism present in LHCII crystals., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The anisotropic organization of plasma membrane constituents is indicative of mechanisms that drive the membrane away from equilibrium. However, defining these mechanisms is challenging due to the short spatiotemporal scales at which diffusion operates. Here, we use high-density single protein tracking combined with photoactivation localization microscopy (sptPALM) to monitor Cdc42 in budding yeast, a system in which Cdc42 exhibits anisotropic organization. Cdc42 exhibited reduced mobility at the cell pole, where it was organized in nanoclusters. The Cdc42 nanoclusters were larger at the cell pole than those observed elsewhere in the cell. These features were exacerbated in cells expressing Cdc42-GTP, and were dependent on the scaffold Bem1, which contributed to the range of mobility and nanocluster size exhibited by Cdc42. The lipid environment, in particular phosphatidylserine levels, also played a role in regulating Cdc42 nanoclustering. These studies reveal how the mobility of a Rho GTPase is controlled to counter the depletive effects of diffusion, thus stabilizing Cdc42 on the plasma membrane and sustaining cell polarity.

Objective: The study was planned to investigate whether DHEA supplementation had an impact on endometrial receptivity in women who were poor responders (POR)., Material and Methods: Twenty-eight POR women who were undergoing hysteroscopy and five fertile control subjects were included. The POR women were equally subdivided into two separate groups as patients who were currently using DHEA and those who were not. Endometrial samples of the subjects were obtained during hysteroscopy at the late follicular phase. Expression levels of endometrial HOXA-10, HOXA-11, and LIF mRNA were measured with the using real-time polymerase chain reaction. Spontaneous clinical pregnancy rates were also noted., Results: Compared with POR women who were not given DHEA, upregulated endometrial HOXA-10 (7.33-fold) and HOXA-11 (2.39-fold) mRNA expression were detected in POR women on DHEA. The increase in HOXA-10 mRNA was significant (p<0.03). The fold increase in HOXA-11 mRNA was found as 2.39, which indicated a positive upregulation. However, this fold increment was insignificant (p<0.45). An insignificant increase in spontaneous clinical pregnancy rates in POR women on DHEA (53.3%) was observed compared with POR women who were not given DHEA (43.8%)., Conclusion: Oral DHEA supplementation in POR upregulates endometrial HOXA-10 mRNA expression, which is known to positively modulate endometrial receptivity.

Scaffold proteins modulate signalling pathway activity spatially and temporally. In budding yeast, the scaffold Bem1 contributes to polarity axis establishment by regulating the GTPase Cdc42. Although different models have been proposed for Bem1 function, there is little direct evidence for an underlying mechanism. Here, we find that Bem1 directly augments the guanine exchange factor (GEF) activity of Cdc24. Bem1 also increases GEF phosphorylation by the p21-activated kinase (PAK), Cla4. Phosphorylation abrogates the scaffold-dependent stimulation of GEF activity, rendering Cdc24 insensitive to additional Bem1. Thus, Bem1 stimulates GEF activity in a reversible fashion, contributing to signalling flux through Cdc42. The contribution of Bem1 to GTPase dynamics was borne-out by in vivo imaging: active Cdc42 was enriched at the cell pole in hypophosphorylated cdc24 mutants, while hyperphosphorylated cdc24 mutants that were resistant to scaffold stimulation displayed a deficit in active Cdc42 at the pole. These findings illustrate the self-regulatory properties that scaffold proteins confer on signalling pathways.

The purpose of this study was to investigate the changes in subfoveal choroidal thickness (SFCT) after intravitreal injection of bevacizumab (IVB) for neovascular age-related macular degeneration (AMD) and diabetic macular edema (DME). This retrospective, consecutive, interventional case series study included 43 eyes [21 affected eyes with neovascular AMD (AMD group) and 22 affected eyes with DME (DME group)] which were treated with 1.25 mg/0.5 ml IVB and 43 untreated fellow eyes of 43 patients. SFCT was measured in all 86 eyes at baseline before IVB injection and at day 1, week 1, and month 1 after injection by use of enhanced depth imaging optical coherence tomography (EDI OCT). Central foveal thickness (CFT) and best-corrected visual acuity were analyzed at baseline and during follow-up visits. Main outcome measure was change in SFCT in 1 month after treatment. All 43 eyes treated with IVB showed a significant reduction in SFCT. Mean SFCT in treated eyes decreased from 237.1 ± 75.3 µm at baseline to 214.0 ± 65.7 µm at day 1, 205.4 ± 59.7 at week 1, and 222.7 ± 73.3 at month 1, whereas SFCT in fellow eyes changed from 228.4 ± 63.6 at baseline to 224.5 ± 68.5 at day 1, 220.4 ± 72.1 at week 1, and 226.9 ± 74.0 at month 1. SFCT demonstrated a similar trend toward decrease in both groups. CFT decreased significantly and visual acuity improved significantly. SFCT decreased significantly in AMD and DME eyes following injection. The decreasing effect of bevacizumab on choroidal thickness was highest at first week and continued to the end of first month after injection.

Objectives: To evaluate the efficacy of intravitreal bevacizumab treatment in type 2 idiopathic macular telangiectasia (IMT)., Materials and Methods: Six eyes of 5 patients with type 2 IMT who received intravitreal bevacizumab between 2009 and 2014 were included in this study. All the patients had an ophthalmological examination including best corrected visual acuity (BCVA), dilated fundus examination, spectral domain optical coherence tomography (OCT) and fluorescein angiography. Intravitreal bevacizumab injection was planned for patients who had macular edema and/or decreased visual acuity at baseline. Patients were examined 1 week and 1 month after the intravitreal injection. Intravitreal injection was repeated in patients whose visual acuity decreased and/or whose macular edema persisted or increased. Changes in BCVA, central macular thickness (CMT) and central macular volume from baseline at 1 month after the first injection and at final examination were evaluated., Results: Average age of the patients (4 female and 1 male) was 62±11.8 years. Average follow-up period was 26±11 months. Patients received an average of 2.3 (range 1-4) injections during follow-up. Average Snellen BCVA of the patients was 0.48±0.29. BCVA increased at final examination compared to baseline in all of the patients. The difference between baseline and final visual acuities was significant (p<0.05). The patients' average CMT was 328±139 µm at baseline and decreased by a mean of 85±153 µm at 1 month after the first injection and 65±142 µm at final examination, but the changes were not significant. CMT decreased at final examination compared to baseline in four patients and increased in both eyes of one patient., Conclusion: Intravitreal bevacizumab injection is a preferable treatment method in regard to both visual acuity and OCT findings., Competing Interests: No conflict of interest was declared by the authors. Financial Disclosure: The authors declared that this study received no financial support.

Objective: A rhinolith is a rare entity affecting all people in all age groups. It is defined as a mineralized foreign body. The purpose of the present study was to reveal the distribution in age and gender and the localization, side, and prominent symptoms of rhinoliths to identify the risk groups and characteristics of the rhinoliths in a large case series., Methods: A retrospective review was performed from the medical charts of 28 patients who were diagnosed with rhinolith and underwent surgery between May 2011 and January 2015 in Ankara Research and Training Hospital. All data, including age, gender, duration of symptoms, localization of the lesion and accompanying pathologies, were documented., Results: In total, 28 patients (18 females and 10 males) with a mean age of 26.2±16.6 (5-62) years who were diagnosed with rhinolithiasis were reviewed. Nasal obstruction (71.4%) and nasal discharge (64.3%) were the most common complaints. The rhinolith was located in the right nasal cavity in 24 patients and in the left in four; this difference was statistically significant (p<0.001). There were 11 accompanying pathologies including nasal septal deviation (n=6), nasal polyposis (n=2), concha bullosa (n=2), and adenoid vegetation (n=1). In 21 (75%) patients, the most common site was the nasal base of the cavity between the inferior turbinate and the nasal septum., Conclusion: If unilateral right-sided nasal obstruction with foul-smelling purulent discharge is detected in a young adult and a nasal examination reveals a mass in the floor of the cavity, a rhinolith should be strongly considered in the differential diagnosis., Competing Interests: Conflict of Interest: No conflict of interest was declared by the authors.

Purpose:: To evaluate subfoveal choroidal thickness (SFCT) changes after intravitreal bevacizumab (IVB) therapy for central serous chorioretinopathy (CSC) using enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT)., Methods:: In this retrospective study, we assessed the medical records of patients with CSC who received IVB (IVB group) or who were observed without intervention (control group). SFCT was measured using EDI-OCT. The main outcome measure was the change in SFCT., Results:: Twenty-one eyes were included in the IVB group and 16 eyes were included in the control group. All patients showed resolution of neurosensory detachment and improvement in vision. In the IVB group, the mean SFCT was 315 μm at baseline, which decreased to 296 μm at the most recent visit. In the control group, the mean SFCT was 307 μm at baseline, which decreased to 266 μm at the most recent visit. Although there was a significant decrease in the mean SFCT for the control group, the decrease was not significant for the IVB group (41 vs 19 μm, p=0.003 vs p=0.071)., Conclusions:: SFCT decreased in both groups with remission of the disease. However, the decrease was significantly greater in the control group. In terms of anatomic and functional outcomes, IVB injection is not promising.

Objective: To evaluate clinical features, complications, visual outcomes and treatment modalities in patients clinically diagnosed with herpetic anterior uveitis (AU)., Materials and Methods: We retrospectively reviewed the medical records of 67 patients seen at the Umraniye Training and Research Hospital, Ophthalmology Clinic, Uveitis and Cornea Department from January 2009 to June 2013., Results: Thirty-seven patients (55.2%) were female and 30 (44.7%) patients were male. The average follow-up period was 12.9 ± 10.6 months (range: 1-45 months). The most common ocular findings were granulomatous keratic precipitates (KPs) (82.2%), corneal involvement (62.6%), iris atrophy (41.7%) and transient elevated intraocular pressure (IOP) (40.2%). Recurrences were observed in 46.2% of the eyes and the median recurrence rate was 1.0 during the follow-up period. Topical steroids and oral antiviral (acyclovir) therapy were applied to all patients during active episodes. Long-term oral acyclovir was used in 29.8% of the patients. Recurrence rates were significantly lower in patients who used oral acyclovir for more than 6 months, whereas complications rates and final visual acuity did not show any difference between groups. Final visual acuity was better than 20/40 in 61.1% of eyes, and visual impairment was due to corneal scarring or cataract formation., Conclusion: Herpetic AU can present with or without corneal involvement. Granulomatous KPs, iris atrophy and elevated IOP are important clinical findings for the diagnosis of cases without corneal involvement. Long-term oral acyclovir treatment (more than 6 months) and is important to decrease recurrence rates and possible complications. Visual prognosis is favorable in cases without corneal scarring., Competing Interests: No conflict of interest was declared by the authors. Financial Disclosure: The authors declared that this study received no financial support.

Purpose: To report our results of 4 patients about the efficacy and safety of intravitreal dexamethasone implant for type 1 idiopathic macular telangiectasia (IMT)., Methods: Four patients' charts with type 1 IMT treated with intravitreal dexamethasone implant were retrospectively reviewed. All patients underwent full ophthalmic examination including best corrected visual acuity (BCVA), spectral domain optical coherence tomography, and fluorescein angiography. BCVA, central macular thickness (CMT), and macular volume (MV) were evaluated., Results: The median BCVA was logMAR 0.55 (range 0.2-1.3) at baseline, improved to logMAR 0.45 (range 0.2-1) at 2 months after the first injection, and deteriorated to logMAR 0.7 (range 0.2-1) at final visit. The median CMT was 393 μm (range 283-410 μm) and MV was 2.70 mm(3) (range 1.96-2.87 mm(3)) at baseline. Two months after the first injection median CMT decreased to 327 μm (range 269-356 μm) and MV decreased to 2.45 mm(3) (range 1.93-2.57 mm(3)). At final visit median CMT slightly increased to 342 μm (range 258-444 μm) and MV slightly increased to 2.56 mm(3) (range 1.93-2.89 mm(3)). None of the changes were statistically significant., Conclusion: Considering the effects of dexamethasone on macular edema intravitreal dexamethasone implant can be used in selected cases. Randomized clinical trials with larger sample size are needed for further evaluation.

In response to changes in the reduction state of the plastoquinone pool in its thylakoid membrane, the green alga Chlamydomonas reinhardtti is performing state transitions: remodelling of its thylakoid membrane leads to a redistribution of excitations over photosystems I and II (PSI and PSII). These transitions are accompanied by marked changes in the 77 K fluorescence spectrum, which form the accepted signature of state transitions. The changes are generally thought to reflect a redistribution of light-harvesting complexes (LHCs) over PSII (fluorescing below 700 nm) and PSI (fluorescing above 700 nm). Here we studied the picosecond fluorescence properties of C. reinhardtti over a broad range of wavelengths with very low excitation intensities (0.2 nJ per laser pulse). Cells were directly used for time-resolved fluorescence measurements at 77 K without further treatment, such as medium exchange with glycerol. It is observed that upon going from state 1 (relatively more fluorescence below 700 nm) to state 2 (relatively more fluorescence above 700 nm), a large part of the fluorescence of LHC/PSII becomes substantially quenched in concurrence with LHC detachment from PSII, whereas the absolute amount of PSI fluorescence hardly changes. These results are in agreement with the recent proposal that the amount of LHC moving from PSII to PSI upon going from state 1 to state 2 is rather limited (Unlu et al. Proc Natl Acad Sci USA 111 (9):3460-3465, 2014).

Purpose: To compare the outcomes of treatment with intravitreal bevacizumab (IVB) versus observation in central serous chorioretinopathy (CSCR)., Methods: In a retrospective comparative study, records of 45 patients with CSCR were reviewed. Twenty-two patients received IVB (1.25 mg/0.05 ml) while 23 subjects were observed. All subjects underwent measurement of best corrected visual acuity (BCVA) and intraocular pressure (IOP), dilated fundus examination and optical coherence tomography (OCT) imaging at baseline and follow up visits. Outcome measures included central macular thickness (CMT) and BCVA in logarithm of minimum angle of resolution (logMAR) notations., Results: Mean age was 44.1 ± 9.3 (range: 24 to 64) years and mean follow-up period was 10.4 ± 11.2 (range: 3 to 43; median: 6) months. All patients demonstrated resolution of neurosensory detachment and improvement in visual acuity. At final visit, there was no significant difference in mean CMT between the IVB and observation groups (275 vs 284 μm, P> 0.05). Mean baseline logMAR visual acuity was 0.38 ± 0.24 in the IVB group which improved to 0.24 ± 0.31 at final follow-up (P = 0.011); mean baseline logMAR visual acuity was 0.42 ± 0.28 in the observation group and improved to 0.12 ± 0.18 (P = 0.001). Visual improvement was more marked in the observation group (0.30 vs 0.14 logMAR, P< 0.05) and mean final visual acuity was also significantly better (P = 0.05)., Conclusion: There was no significant difference between IVB injection and observation in terms of anatomical outcomes of treatment for CSCR. In terms of visual outcomes, observation was superior to IVB injection.

Purpose. To evaluate the relationship between internal carotid artery (ICA) stenosis and subfoveal choroidal thickness (SFCT) in the elderly population. Methods. A total of 42 eyes of 21 patients with more than 70% ICA stenosis (Group 1) on one side and less than 70% stenosis (Group 2) on the other side were recruited for this study. ICA stenosis was diagnosed using both the B-mode and Doppler ultrasound. The two groups were compared in terms of the percentage of stenosis, SFCT measurements, intraocular pressure, ocular perfusion pressure, refractive error, and peak systolic velocity. Eyes were examined with the RTVue-100 OCT device by the EDI-OCT technique. Results. The mean age of the patients was 71.9 ± 10.8 years. The mean percentage of ICA stenosis was 74 ± 4.9% in Group 1 and 47.5 ± 7.7% in Group 2. The mean SFCT was 231.9 ± 44.6 μm in Group 1 and 216.2 ± 46.8 μm in Group 2, which was significantly lower (P = 0.028). A statistically significant positive correlation was found between the percentage of internal carotid artery stenosis and SFCT (r = 0896, P = 0.001). Conclusions. Compensatory SFCT increase can be seen in ipsilateral internal carotid artery stenosis greater than 70%.

A 17-year-old presented with central and paracentral scotomas in his right eye for one week. There was no remarkable medical or ocular history. Blood analyses were within normal range. At presentation both eyes' best-corrected visual acuities were 20/20. Slit-lamp examination result was normal. Fundus examination revealed yellow-white hypopigmented areas in the macula. Fluorescein angiography (FA) showed hypofluorescence surrounded by ring of hyperfluorescence. Fundus autofluorescence (FAF) was slightly increased. Spectral domain optical coherence tomography (SD-OCT) showed disruption of IS/OS junction with expansion of abnormal hyperreflectivity from retinal pigment epithelium to the outer nuclear layer (ONL). One month later fundus examination showed disappearance of the lesions. FA revealed transmission hyperfluorescence. FAF showed increased autofluorescence and pigment clumping. Hyperreflective band in SD-OCT disappeared. Loss of photoreceptor segment layers was observed in some of the macular lesions. The diagnosis of acute retinal pigment epitheliitis can be challenging after disappearance of fundus findings. FA, FAF, and SD-OCT are important tests for diagnosis after resolution of the disease.

Minor light-harvesting complexes (Lhcs) CP24, CP26 and CP29 occupy a position in photosystem II (PSII c' plants between the major light-harvesting complexes LHCII and the PSII core subunits. Lack of minor Lhcs in vivo causes impairment of PSII organization, and negatively affects electron transport rates anc photoprotection capacity. Here we used picosecond-fluorescence spectroscopy to study excitation-energy transfer (EET) in thylakoid membranes isolated from Arabidopsis thaliana wild-type plants and knockout lines depleted of either two (koCP26/24 and koCP29/24) or all minor Lhcs (NoM). In the absence of all minor Lhcs. the functional connection ofLHCII to the PSII cores appears to be seriously impaired whereas the "disconnected" LHCII is substantially quenched. For both double knock-out mutants, excitation trapping in PSII is faster than in NoM thylakoids but slower than in WT thylakoids. In NoM thylakoids, the loss of all minor Lhcs is accompanied by an over-accumulation ofLHCII, suggesting a compensating response to the reduced trapping efficiency in limiting light, which leads to a photosynthetic phenotype resembling that of low-light-acclimated plants. Finally. fluorescence kinetics and biochemical results show that the missing minor complexes are not replaced by other Lhcs, implying that they are unique among the antenna subunits and crucial for the functioning and macroorganization of PSII.

Purpose: To evaluate the surgical outcomes of slanted medial rectus recession in patients diagnosed as having convergence excess esotropia., Methods: Bilateral slanted recession of medial rectus muscles was performed in 16 patients with convergence excess esotropia. The lower margins of medial rectus muscles were recessed 1 to 2 mm more than the upper margins. Changes in near-distance disparity of the deviations were recorded., Results: The mean preoperative near-distance disparity of 20.3±6.5 prism diopters (PD) decreased to 4.37±5.6 PD postoperatively. The amount of collapse was significant (mean: 16 PD; P<.005). Near-distance disparity of 10 PD or less was obtained in 14 patients after surgery (87.5%), except 2 patients who had 16 PD of disparity. The authors did not encounter overcorrection except in 1 patient in whom minimal exophoria at distance and near with the glasses was observed and reduced the prescription., Conclusions: Bilateral slanted medial rectus muscle recession procedure effectively decreases the disparity between near and distance deviations in patients with convergence excess esotropia., (Copyright 2014, SLACK Incorporated.)