39 research outputs found

    Compressive Photon-Sieve Spectral Imaging

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    We develop a new compressive spectral imaging modality that utilizes a coded aperture and a photon-sieve for dispersion. The 3D spectral data cube is successfully reconstructed with as little as two shots using sparse recover

    Investigation of the effect of quercetin in an experimental oxygen-induced retinopathy model

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    Aim: Investigation of the effect of intraperitoneal (IP) quercetin and bevacizumab on oxygen-induced retinopathy (OIR) model in rats. Methods: In the study, 28 newborn rats were used. The OIR model was performed with the 50/10% oxygen technique. The study consisted of four groups as a control group (Group I) and OIR groups (Group II, III, and IV). IP injection applied to all groups on the postnatal day (PND) 14. Groups I and II were performed 0.9% NaCl, Group III was performed IP bevacizumab, and Group IV was performed IP quercetin. All animals were sacrificed on PND 18. Results: Based on the data obtained from immunohistochemical and histopathological examinations, the number of vascular endothelial cell (VEC), vascular endothelial growth factor (VEGF), and tumor necrosis factor-α (TNF-α) levels were significantly reduced in Group III and IV compared to Group II. VECs levels were 0±0, 32.69±5.77, 2.92±0.63, and 3.64±0.36 in Group I, Group II, Group III, and Group IV, respectively (p<0.001). Likewise, VEGF values were 0.15±0.01, 7.57±1.80, 2.45±0.45, and 2.46±0.49, respectively (p<0.001). As well as TNF-α values were 0.06±0.01, 8.22±2.24, 2.32±0.32, and 2.29±0.26 in Group I, Group II, Group III, and Group IV, respectively (p<0.001). There was no significant difference between Group III and Group IV in terms of VEC, VEGF and TNF-α values (range of p values was 0.96-1.00). Conclusion: The results of the present study showed that quercetin administration significantly reduced the VEC number and suppressed VEGF and TNF-α. Quercetin's anti-inflammatory and anti-angiogenesis effect was found to be similar to bevacizumab

    Evaluation of retinal nerve fiber layer and ganglion cell layer thicknesses with optical coherence tomography in patients with vitamin B12 deficiency

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    Aim: We aimed to compare the retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness of B12 vitamin deficiency patients with healthy controls using optical coherence tomography (OCT). Methods: Forty-six patients (27 females / 19 males) diagnosed with B12 vitamin deficiency and 46 healthy controls (26 females / 20 males) with similar age and sex were included in the study. RNFL thickness of global, superotemporal, temporal, inferotemporal, superonasal, nasal and inferonasal sectors and GCL thickness and volume measurements of central, superior, inferior, temporal, and nasal sectors were performed using Spectralis-OCT device in all cases. Results: The mean age of the patient group was 42.17±15.34 years, while that of the control group was 44.21±12.34 years (p=0.528). Mean serum vitamin B12 levels were measured as 163,47±19,80 pg/ml in the patient group and 311,80±76,30 pg/ml in the control group (p <0,01). There was no statistically significant difference between the global RNFL thicknesses of the two groups (p> 0,05). However, statistically non-significant thinning was observed in the superotemporal and global RNFL thickness of the group with B12 vitamin deficiency (p values are 0,140 and 0,171, respectively). There was also no statistically significant difference between GCL thicknesses and volumes of the two groups (p> 0.05). Conclusions: No significant reduction was observed in RNFL and GCL thicknesses of adult subjects with B12 vitamin deficiency compared with healthy controls

    High Dose of Caffeine Mouth Rinse Increases Resistance Training Performance in Men

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    Caffeine mouth rinsing (CMR) has been shown to enhance exercise performance. However, no studies have analyzed the effects of different dosages of CMR on muscular performance. Therefore, the purpose of this study was to examine the effects of different dosages of CMR on strength (bench press 1 repetition maximum (1-RM)) and muscular endurance (60% of 1-RM repetitions to failure) in resistance-trained males. Fourteen resistance-trained males (age: 23 ± 2 years, height: 179 ± 3 cm, body mass: 83 ± 4 kg, BMI: 17 ± 2 kg/m2) completed four conditions in random order. The four conditions consisted of a mouth rinse with 25 mL solutions containing either 1% (250 mg) of CMR (low dose of CMR: LCMR), 2% (500 mg) of CMR (moderate dose of CMR: MCMR), 3% (750 mg) of CMR (high dose of CMR: HCMR) and sweetened water (placebo: PLA) for 5 s prior to a bench press strength and muscular endurance test. Maximal strength, muscular endurance, heart rate (HR) and ratings of perceived exertion (RPE) were recorded for each condition. There were no significant differences in strength (p = 0.30) and HR (p = 0.83) between conditions. HCMR significantly increased muscular endurance performance (p = 0.01) and decreased RPE values (p = 0.01). In conclusion, CMR did not affect bench press 1-RM strength performance, but muscular endurance responses to CMR seems to be dose-dependent

    Attractive versus Repulsive Excitonic Interactions of Colloidal Quantum Dots Control Blue- to Red-Shifting (and Non-shifting) Amplified Spontaneous Emission

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    Tunable, high-performance, two-photon absorption (TPA)-based amplified spontaneous emission (ASE) from near-unity quantum efficiency colloidal quantum dots (CQDs) is reported. Besides the absolute spectral tuning of ASE, the relative spectral tuning of ASE peak with respect to spontaneous emission was shown through engineering excitonic interactions in quasi-type-II CdSe/CdS core/shell CQDs. With core shell size adjustments, it was revealed that Coulombic exciton-exciton interactions can be tuned to be attractive (type-I-like) or repulsive (type-II-like) leading to red- or blue-shifted ASE peak, respectively, and that nonshifting ASE can be achieved with the right core shell combinations. The possibility of obtaining ASE at a specific wavelength from both type-I-like and type-II-like CQDs was also demonstrated. The experimental observations were supported by parametric quantum-mechanical modeling, shedding light on the type-tunability. These excitonically engineered CQD-solids exhibited TPA-based ASE threshold as low as 6.5 mJ/cm(2) under 800 nm excitation, displaying one of the highest values of TPA cross-section of 44 660 GM

    A Systematic Review and Meta-analysis of the Relationships among Post-secondary Students’ Attitudes Toward Statistics and Statistics Achievement

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    Background: An understanding of statistics is essential in our data-driven world. Accordingly, successful completion of a statistics course is required for undergraduate and graduate students from many disciplines. Attitudes toward statistics is a multidimensional construct that expresses individuals’ positive or negative dispositions to statistics. A wide body of research indicates that there are statistically significant relationships among attitudes toward statistics and statistics achievement. However, the reported magnitudes of these relationships differ across studies.  Methods/Design: This review will examine the relationships among post-secondary students’ scores on the attitude components assessed by the Survey of Attitudes toward Statistics (SATS) and their statistics achievement assessed using a variety of measures. As the data allow, this review then will explore the impact of possible moderating research characteristics including, for example, those associated with research sources, institutions, courses, subjects, and the SATS and statistics achievement measures. Discussion: In the resulting journal article, this section will focus on the results and the strengths and limitations of the synthesized literature. We expect that the study will contribute to the literature on the relationship between attitudes toward statistics and achievement by synthesizing the individual research results. The availability of the required information and the quality of primary studies will be potential limitations for the current study

    Evaluation of the safety of intracameral trypan blue injection on corneal tissue using oxidative stress parameters and apoptotic activity: an experimental study

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    Purpose: The present experimental study aimed to investigate the effects of intracameral trypan blue (TB) on oxidative stress parameters and apoptosis in corneal tissue. Methods: Thirty rats were randomly assigned to three groups of 10 rats each: the sham group (Group 1); control group (Group 2); and treatment group (Group 3). The control group was administered 0.01 cc of balanced salt solution. The treatment group was administered 0.006 mg/0.01 cc of TB. The total antioxidant status (TAS) and total oxidant status (TOS) in corneal tissue and blood were measured and the oxidative stress index (OSI) was calculated. Finally, corneal tissue histopathology was evaluated using staining for caspase-3 and -8, and apoptotic activity was examined. Results: The TAS, TOS and OSI levels in the blood samples were not significantly different (p>0.05 for all). Compared with the sham and control groups, the TOS and OSI levels in corneal tissue were significantly different in the treatment group (p<0.05 for all). No significant difference was observed between the sham group and the control group (p>0.05). Immunohistochemical staining for caspase-3 and caspase-8 demonstrated higher apoptotic activity in the TB group than in the sham and control groups. Conclusion: The present study showed that intracameral TB injection is safe systematically but may be toxic to corneal tissue, as demonstrated using oxidative stress parameters and histopathological evaluation

    Physiological parameters for Prognosis in Abdominal Sepsis (PIPAS) Study : a WSES observational study

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    BackgroundTiming and adequacy of peritoneal source control are the most important pillars in the management of patients with acute peritonitis. Therefore, early prognostic evaluation of acute peritonitis is paramount to assess the severity and establish a prompt and appropriate treatment. The objectives of this study were to identify clinical and laboratory predictors for in-hospital mortality in patients with acute peritonitis and to develop a warning score system, based on easily recognizable and assessable variables, globally accepted.MethodsThis worldwide multicentre observational study included 153 surgical departments across 56 countries over a 4-month study period between February 1, 2018, and May 31, 2018.ResultsA total of 3137 patients were included, with 1815 (57.9%) men and 1322 (42.1%) women, with a median age of 47years (interquartile range [IQR] 28-66). The overall in-hospital mortality rate was 8.9%, with a median length of stay of 6days (IQR 4-10). Using multivariable logistic regression, independent variables associated with in-hospital mortality were identified: age > 80years, malignancy, severe cardiovascular disease, severe chronic kidney disease, respiratory rate >= 22 breaths/min, systolic blood pressure 4mmol/l. These variables were used to create the PIPAS Severity Score, a bedside early warning score for patients with acute peritonitis. The overall mortality was 2.9% for patients who had scores of 0-1, 22.7% for those who had scores of 2-3, 46.8% for those who had scores of 4-5, and 86.7% for those who have scores of 7-8.ConclusionsThe simple PIPAS Severity Score can be used on a global level and can help clinicians to identify patients at high risk for treatment failure and mortality.Peer reviewe

    A CMOS High Frequency Pulse Width Modulation Integrated Circuit

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    In this work, a high frequency pulse width modulation (PWM) integrated circuit (IC) designed and implemented in a commercial 0.35 mu m CMOS process is presented. Based on natural sampling method, the proposed PWM IC can generate both a PWM signal and its inverse for arbitrary frequencies up to 5 MHz. The PWM frequency can he adjusted via an external clock and an off-chip capacitor. The duty cycle of the PWM signal can be linearly varied from 5% to 95% by changing the input signal. Thanks to its analog triangle wave generation, it provides higher resolution and less quantization error compared to digital implementations. Moreover, the natural sampling based PWM generation offers reduced harmonic distortion over other PWM generation methods. The PWM IC requires a single 5 V supply voltage to operate. The full chip area is 1.4x1.8 mm(2), including the pad frame. The post-layout simulations reveal that the proposed PWM IC will be a compact and high performance solution for power converters and class D power amplifiers

    Evaluation of subjects with a moderate cup to disc ratio using optical coherence tomography and Heidelberg retina tomograph 3: Impact of the disc area

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    Aim: The aim was to evaluate subjects with a moderate cup to disc ratio using optical coherence tomograph (OCT) and Heidelberg retina tomograph (HRT) 3. Settings and Design: We included 80 patients with early glaucoma and 80 nonglaucomatous subjects with moderate cup/disc ratio (range of 0.5-0.8) to this cross-sectional study. Subjects and Methods: We compared results of color-coded algorithms of HRT 3 (Moorfields regression analysis [MRA] and Glaucoma probability score [GPS]) and OCT. All outputs are classified into three categories: Within normal limits (WNLs), borderline and outside normal limits (ONLs). Diagnostic accuracies of algorithms were determined using the highest sensitivity criteria. Results: The sensitivities of global MRA, GPS and OCT were 0.75, 0.925 and 0.725, respectively, in average disc area group and 0.85, 1.0 and 0.425, respectively, in large disc area group. The specificities of global MRA, GPS and OCT were 0.55, 0.15 and 0.85, respectively, in average disc area group and 0.425, 0.025 and 0.80, respectively, in large disc area group. Area under receiver operating characteristic curve (AUROC) of global MRA, GPS and OCT were 0.667, 0.617 and 0.792, respectively, in average disc area group and 0.746, 0.576 and 0.627, respectively, in large disc area group. AUROC of global MRA and OCT combination in the average and large disc area groups were 0.828 and 0.825, respectively. Conclusions: In contrast to GPS and OCT algorithms, diagnostic performance of MRA algorithm increased in large disc area group. Combining MRA and OCT algorithms produced satisfactory diagnostic performance in subjects with an average and large disc area
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