Polarization-pinned emission of a continuous-wave optically pumped nonpolar GaN-based VCSEL using nanoporous distributed Bragg reflectors.

A nonpolar GaN-based vertical-cavity surface-emitting laser (VCSEL) using nanoporous bottom epitaxial distributed Bragg reflector (DBR) is demonstrated at room temperature (RT) under continuous-wave (CW) optical pumping. The porous layers enable the epitaxial growth of lattice-matched high-reflectance DBRs without sacrificing the conductive properties needed for high-performance VCSELs. The 2-λ cavity VCSEL reported here employs a hybrid design with top dielectric DBR and bottom nanoporous DBR. Single longitudinal mode lasing is observed at 462 nm with a threshold power density of ~5 kW/cm2 and a FWHM of ~0.12 nm. The emission polarization was pinned in the a-direction at all measured locations.

Test-retest reliability of Kinect's measurements for the evaluation of upper body recovery of stroke patients.

BACKGROUND: Performance indices provide quantitative measures for the quality of motion, and therefore, assist in analyzing and monitoring patients' progress. Measurement of performance indices requires costly devices, such as motion capture systems. Recent developments of sensors for game controllers, such as Microsoft Kinect, have motivated many researchers to develop affordable systems for performance measurement applicable to home and clinical care. In this work, the capability of Kinect in finding motion performance indices was assessed by analyzing intra-session and inter-session test-retest reliability. METHOD: Eighteen stroke patients and twelve healthy subjects participated in this investigation. The intra-session and inter-session reliability of eight performance indices, namely mean velocity (MV), normalized mean speed (NMS), normalized speed peaks (NSP), logarithm of dimensionless jerk (LJ), curvature (C), spectral arc length (SAL), shoulder angle (SA), and elbow angle (EA), were assessed using intra-class correlation coefficient (ICC), standard error of measurement (SEM) and coefficient of variation (CV). RESULTS: The results showed that, among the performance indices, MV, LJ, C, SA and EA have more than 0.9 ICC together with an acceptable SEM and CV in both stroke patients and healthy subjects. Comparing the results of different therapy sessions showed that MV, LJ and C are more sensitive than other indices, and hence, more capable of reflecting the progress of a patient during the rehabilitation process. CONCLUSION: The results of this study shows acceptable reliability and sensitivity across the sessions for MV, LJ and C measured by Kinect for both healthy subjects and stroke patients. The results are promising for the development of home-based rehabilitation systems, which can analyze patient's movements using Kinect as an affordable motion capture sensor.

The effect of self-aromatherapy massage of the abdomen on the primary dysmenorrhoea.

Primary dysmenorrhoea (PD) is the most common gynaecological complaint that occurs in women. This study was a randomised controlled trial. The subjects were 75 students whose severity of pain was measured by visual analogue scale (VAS). Subjects were randomly divided into three groups: massage group with rose oil (n = 25) who applied self-massage with Rose damascene; a placebo group (n = 25) who performed self-massage with unscented almond oil and a no treatment control group (n = 25) who applied just self-massage. All three groups received the intervention in the first day of menstruation in two subsequent cycles. The severity of pain was self-reported by the students before and after intervention. All three groups were matched in demographic characteristics. The baseline pain reduced in the first cycle but this reduction was not significant in the groups (p > 0.05). In the second cycle, the menstrual pain was significantly lower in the rose oil group than in the other two groups after intervention (between massage with rose oil, almond oil p = 0.003 and massage with rose oil and just massage p = 0.000). Massage with aromatherapy reduces the severity of primary dysmenorrhoea, in comparison with massage therapy alone.

Semantic segmentation of urban environments: Leveraging U-Net deep learning model for cityscape image analysis.

Semantic segmentation of cityscapes via deep learning is an essential and game-changing research topic that offers a more nuanced comprehension of urban landscapes. Deep learning techniques tackle urban complexity and diversity, which unlocks a broad range of applications. These include urban planning, transportation management, autonomous driving, and smart city efforts. Through rich context and insights, semantic segmentation helps decision-makers and stakeholders make educated decisions for sustainable and effective urban development. This study investigates an in-depth exploration of cityscape image segmentation using the U-Net deep learning model. The proposed U-Net architecture comprises an encoder and decoder structure. The encoder uses convolutional layers and down sampling to extract hierarchical information from input images. Each down sample step reduces spatial dimensions, and increases feature depth, aiding context acquisition. Batch normalization and dropout layers stabilize models and prevent overfitting during encoding. The decoder reconstructs higher-resolution feature maps using "UpSampling2D" layers. Through extensive experimentation and evaluation of the Cityscapes dataset, this study demonstrates the effectiveness of the U-Net model in achieving state-of-the-art results in image segmentation. The results clearly shown that, the proposed model has high accuracy, mean IOU and mean DICE compared to existing models.

Exploring the potential of standalone and tandem solar cells with Sb2S3 and Sb2Se3 absorbers: a simulation study.

Thin-film antimony chalcogenide binary compounds are potential candidates for efficient and low-cost photovoltaic absorbers. This study investigates the performance of Sb2S3 and Sb2Se3 as photovoltaic absorbers, aiming to optimize their efficiency. The standalone Sb2S3 and Sb2Se3 sub-cells are analyzed using SCAPS-1D simulations, and then a tandem structure with Sb2S3 as the top-cell absorber and Sb2Se3 as the bottom-cell absorber is designed, using the filtered spectrum and the current matching technique. The optimal configuration for maximum efficiency is achieved by adjusting the thickness of the absorber layer. The results show that antimony chalcogenide binary compounds have great potential as photovoltaic absorbers, enabling the development of efficient and low-cost solar cells. A remarkable conversion efficiency of 22.2% is achieved for the optimized tandem cell structure, with absorber thicknesses of 420 nm and 1020 nm for the top and bottom sub-cells respectively. This study presents a promising approach towards high-performance tandem solar cells.

Bibliometric analysis on the adoption of artificial intelligence applications in the e-health sector.

Artificial Intelligent (AI) applications in e-health have evolved considerably in the last 25 years. To track the current research progress in this field, there is a need to analyze the most recent trend of adopting AI applications in e-health. This bibliometric analysis study covers AI applications in e-health. It differs from the existing literature review as the journal articles are obtained from the Scopus database from its beginning to late 2021 (25 years), which depicts the most recent trend of AI in e-health. The bibliometric analysis is employed to find the statistical and quantitative analysis of available literature of a specific field of study for a particular period. An extensive global literature review is performed to identify the significant research area, authors, or their relationship through published articles. It also provides the researchers with an overview of the work evolution of specific research fields. The study's main contribution highlights the essential authors, journals, institutes, keywords, and states in developing the AI field in e-health.

Fish-like three-dimensional swimming with an autonomous, multi-fin, and biomimetic robot.

Fish migrate across considerable distances and exhibit remarkable agility to avoid predators and feed. Fish swimming performance and maneuverability remain unparalleled when compared to robotic systems, partly because previous work has focused on robots and flapping foil systems that are either big and complex, or tethered to external actuators and power sources. By contrast, we present a robot-the Finbot-that combines high degrees of autonomy, maneuverability, and biomimicry with miniature size (160 cm3). Thus, it is well-suited for controlled three-dimensional experiments on fish swimming in confined laboratory test beds. Finbot uses four independently controllable fins and sensory feedback for precise closed-loop underwater locomotion. Different caudal fins can be attached magnetically to reconfigure Finbot for swimming at top speed (122 mm s-1≡ 1 BL s-1) or minimal cost of transport (CoT = 8.2) at Strouhal numbers as low as 0.53. We conducted more than 150 experiments with 12 different caudal fins to measure three key characteristics of swimming fish: (i) linear speed-frequency relationships, (ii) U-shaped CoT, and (iii) reverse Kármán wakes (visualized with particle image velocimetry). More fish-like wakes appeared where the CoT was low. By replicating autonomous multi-fin fish-like swimming, Finbot narrows the gap between fish and fish-like robots and can address open questions in aquatic locomotion, such as optimized propulsion for new fish robots, or the hydrodynamic principles governing the energy savings in fish schools.

Semi-Lagrangian lattice Boltzmann model for compressible flows on unstructured meshes.

Compressible lattice Boltzmann model on standard lattices [M. H. Saadat, F. Bösch, and I. V. Karlin, Phys. Rev. E 99, 013306 (2019).2470-004510.1103/PhysRevE.99.013306] is extended to deal with complex flows on unstructured grid. Semi-Lagrangian propagation [A. Krämer et al., Phys. Rev. E 95, 023305 (2017).2470-004510.1103/PhysRevE.95.023305] is performed on an unstructured second-order accurate finite-element mesh and a consistent wall boundary condition is implemented which makes it possible to simulate compressible flows over complex geometries. The model is validated through simulation of Sod shock tube, subsonic and supersonic flow over NACA0012 airfoil and shock-vortex interaction in Schardin's problem. Numerical results demonstrate that the present model on standard lattices is able to simulate compressible flows involving shock waves on unstructured meshes with good accuracy and without using any artificial dissipation or limiter.

Electron scattering in a superlattice of line defects on the surface of topological insulators.

The electron scattering from periodic line defects on the surface of topological insulators with hexagonal warping effect is investigated theoretically by means of a transfer matrix method. The influence of surface line defects, acting as structural ripples on propagation of electrons are studied in two perpendicular directions due to the asymmetry of warped energy contour under momentum exchange. The transmission profiles and the details of resonant peaks which vary with the number of defects and the strength of their potentials are strongly dependent on the direction in which the line defects extend. At low energies, the quantum interference between the incident and reflected propagating electrons has the dominant contribution in transmission resonances, while at high energies the multiple scattering processes on the constant-energy contour also appear because of the strong warping effect. By increasing the spatial separation between the line defects, the minimum value of electrical conductance remains significantly high at low incident energies, while the minimum value may approach zero at high energies as the number of defects is increased. Our findings suggest that the potential ripples on the surface of topological insulators can be utilized to control the local electronic properties of these materials.

Antibacterial activity and composition of the essential oil of Nepeta hormozganica Jamzad from Iran.

The composition and antibacterial activity of the essential oil of the aerial flowering parts of Nepeta hormozganica Jamzad have been studied. Analysis of the oil was conducted by GC-FID and GC-MS. Thirty-two components were characterized accounting for 99.4% of the total oil. Oxygenated monoterpenes (87.5%) were found to be the predominant group of compounds, of which 18-cineole (65.0%) and 4aα-7α-7aß-nepetalactone (13.0%) were the main constituents. The antibacterial activity of the essential oil and its main constituents showed that all of the tested microorganisms were highly inhibited by the essential oil with inhibition zones ranged from 12 to 24 mm. The most sensitive bacteria were Staphylococcus aureus and Staphylococcus epidermidis with the lowest MIC values of 0.3 and 0.6 mg/mL, respectively. Considering sensitivity screening it is conceivable that the activity of the oil from N. hormozganica could be attributed mainly to the synergistic property of 18-cineole and nepetalactone.

Occupational sunlight exposure, polymorphism of glutathione S-transferase M1, and senile cataract risk.

BACKGROUND: The pathogenesis of cataract is influenced by a number of factors including oxidative stress. Glutathione S-transferase (GST) catalyses the nucleophilic addition of the thiol of GST to electrophilic acceptors. It is important for detoxification of xenobiotics in order to protect tissues from oxidative damage. OBJECTIVES: To examine whether the interaction of polymorphism of GSTM1 gene and occupational sunlight exposure modulate the risk of cataract. METHODS: Blood samples from 95 subjects with cataract and 95 age and sex matched healthy persons were collected. The genotypes of GSTM1 were determined using PCR. RESULTS: The null genotype of GSTM1 was associated with an increase in cataract risk in the indoor workplace, but this association was not significant in the outdoor subjects. CONCLUSION: The active genotype of GSTM1 has lost its protective role in persons who work outdoors. It is suggested that activity of the GSTmu enzyme may be inhibited in the human lens after occupational exposure to UV light.

Tagging sentinel lymph nodes: a study of 100 patients with breast cancer.

The aim of this study was to evaluate in breast cancer patients the feasibility of sentinel lymph node (SLN) identification and the sensitivity of this technique to detect node metastases. Between January and July 1997, SLNs were tracked with Evans Blue dye in 100 patients with breast cancer who then underwent complete level I/II axillary lymph node dissection (ALND). All SLNs were examined by haematoxylin-phloxin-saffron (HPS) staining and immunohistochemistry (IHC) of multiple sections. The findings for the SLNs were compared with results on ANLD. Axillary SLNs were identified in 83 patients (detection rate = 83%; 95% confidence interval (CI) 74-90%). Axillary SLNs were detected in 58/83 cases (70%) at level I only, and in 69/83 (83%) at levels including level I. Histologically positive axillary SLNs were found in 45% (37/83) of patients, including 2 patients with malignancy (micro-metastases) detected by IHC only. The sensitivity of axillary SLN to detect axillary lymph nodes metastases was 37/39 = 95% (95% CI 83-99%). SLNs of the internal mammary chain (IMC) were dissected for 33 tumours of the median or inner quadrants and detected in 26/33 = 79% of cases (95% CI 61-91%). In our experience, the overall sensitivity of SLN identification as a predictor of node (axillary or IMC) metastases was 41/43 = 95% (95% CI 84-99%), confirming the usefulness of the procedure.

Glutathione S-transferase M1 and T1 null genotypes and the risk of gastric and colorectal cancers.

Several polymorphic glutathione S-transferase (GST) enzymes are involved in the detoxification of active metabolites of many potential carcinogens and may therefore be important in modulating susceptibility to cancers. GSTM1 and GSTT1 are polymorphic, and the null alleles result in a lack of corresponding enzyme activities. Previous studies demonstrated that the GSTM1 and GSTT1 null genotypes correlated with an increased risk of developing some cancers. In this study, we determined GSTM1 and GSTT1 polymorphisms in a population of 131 healthy controls from the south of Iran, 46 patients with colorectal cancers, and 42 patients with gastric cancer. The gastric cancer risk statistically increased due to the GSTM1 null genotype (odds ratio (OR)=2.3, 95% confidence interval (CI): 1.15--4.95). On the other hand, the GSTT1 null genotype in gastric cancer and null genotypes of GSTM1 and GSTT1 in colorectal cancer were not statistically significant. Moreover, individuals showing the GSTM1 and GSTT1 null genotypes might exhibit a greater predisposition to gastric (OR=3.31, 95% CI: 1.14--9.57) and colorectal (OR=2.73, 95% CI: 0.94--7.95, P=0.07) cancers.

The glutathione S-transferase mu polymorphism and susceptibility to acute lymphocytic leukemia.

It has been postulated that the absence of glutathione S-transferase mu (GSTmu), which impairs detoxification of some carcinogens, might predispose some individuals to the development of certain cancers. In the present study, polymorphism of GSTM1 were detected by polymerase chain reaction (PCR) in 38 patients with acute lymphocytic leukemia and 75 normal subjects. The null genotype of GSTM1 was significantly more common among leukemic patients compared with the normal control group (55.3 vs. 32.0%; P<0.025). The absence of the GSTmu enzyme may increase the risk of the development of leukemia.

Neoplastic alterations in subcellular distribution of type 1 alpha protein phosphatase in rat ascites hepatoma cells.

Neoplastic alterations of type 1 alpha protein phosphatase (PP1 alpha) have been studied in rat ascites hepatoma cells, using regenerating liver after partial hepatectomy and normal rat liver as controls. In the particulate fraction of hepatomas, potential PP1 activity and the amount of PP1 alpha were remarkably increased compared with either regenerating or normal livers. In the nuclear fraction, PP1 activity and the amount of PP1 alpha were increased in hepatoma compared with the controls. The nuclear PP1 activity in hepatomas was activated by treatment with CO2+/trypsin, whereas that of normal or regenerating liver was not activated. These characteristic alterations of PP1 alpha in its amount and subcellular distribution may be implicated in malignant phenotype(s) such as uncontrolled cell growth.

Influence of GSTT1 null genotype on the offspring sex ratio of gasoline filling station workers.

The aim of this study was to investigate whether the occupational exposure to gasoline of men employed at filling stations affects the sex of their children. Altogether 115 offspring (47 males, 68 females) were identified within families of 49 men working in filling stations in Shiraz (Fars province, south of Iran) and 345 offspring (178 males, 167 females) from 147 families of unexposed persons from the general population of Shiraz, which were matched by age of fathers (+/-2 years) and number of children as a control group. The offspring sex ratio at birth (male proportion) in the filling station workers was significantly lower than the ratio in control group (OR = 0.65; 95% confidence intervals (CI) 0.42 to 0.99). Genotypes of glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) were investigated on extracted genomic DNA of 37 exposed workers using the polymerase chain reaction based method. In exposed group with active GSTM1 and GSTT1 genes, offspring sex ratio was the same as the ratio in the control group (OR = 0.66; 95% CI 0.34 to 1.28). However, in the exposed group with active GSTM1 and null genotype of GSTT1, the offspring sex ratio statistically decreased (OR = 0.45; 95% CI = 0.21 to 0.96). It seems that the GSTT1 null genotype has an effect on offspring sex ratio in the filling station workers.

mRNA levels and enzyme activities of protein phosphatases in drug-resistant rat ascites hepatomas.

mRNA levels and enzyme activities of the serine/threonine protein phosphatases (EC 3.1.3.16) type 1 (PP1) and 2A (PP2A) in drug-resistant rat ascites hepatoma cells were examined and compared with those in the parental drug-sensitive cell lines, under drug-free conditions. The mRNA levels of PP1 alpha were much higher in all the hepatomas, either sensitive or resistant, compared with normal liver. The mRNA level of PP2C alpha was decreased in the drug-resistant hepatomas compared with the parental drug-sensitive hepatomas, whereas mRNA levels of PP1 alpha, PP1 gamma 1 and PP2A alpha in resistant hepatomas showed diverse deviations, which are not drug-resistance-specific. However, both spontaneous and potential PP1 activities in particulate fractions of the resistant hepatomas were markedly increased compared with those of the sensitive hepatomas and normal rat liver. Western blot analysis showed that the resistant hepatomas contained larger amounts of PP1 alpha in both cytosolic and particulate fractions than the sensitive hepatomas and rat liver. In both groups of hepatomas, spontaneous and potential activities of PP2A were kept lower than those in normal rat liver, but there was no difference between drug-sensitive and -resistant hepatomas. These results suggest an involvement of PP1 in development of drug-resistant phenotype.

Diagnosis of adolescent pregnancy--1965 vs 1980.

The study compares changes in the accuracy of the diagnosis of pregnancy in adolescents between 1965 and 1980. We compared 44 records of adolescents evaluated in 1965 to those of 44 who were evaluated 15 years later in 1980. The following data were examined: (1) reason for consultation, (2) amount of time prior to making the correct diagnosis, and (3) the most common diagnostic errors. The results showed that (1) the initial diagnosis was correct only 75 per cent of the time in 1965 and 86 per cent in 1980, (2) both in 1965 and 1980 most patients initially consulted for "vague complaints," (3) in 1965 and 1980 the most common diagnostic errors were "gastrointestinal disorder" and "functional symptoms," and (4) pregnancy was diagnosed earlier in 1980 than in 1965. Improvement in diagnostic accuracy should be possible if clinicians screen for pregnancy in adolescent girls consulting for vague symptoms such as nausea, weight gain, urticaria, and somnolence.

Effect of exercise on bone mineral metabolism in diabetes.

The authors attempt to assess the relationship between exercise, diabetes, and bone metabolism. An animal model system was developed to study the relationship. Animals given streptozotocin to induce a type I diabetic state show elevated plasma glucose and triglyceride levels and a decrease in body weight. Analysis of femurs revealed alterations in copper, phosphorus, and zinc levels in animals with diabetes compared with controls. Mineral analysis of femurs from diabetic animals placed on an exercise regimen revealed values closer to control levels.