Evaluation of renovated double J stents using ureter models with and without stenosis.

PURPOSE: Commercial double J stents (DJS) have a uniform shape regardless of the specific nature of various ureteral diseases. We tested renovated DJS and compared them with conventional DJS using ureter models. METHODS: One straight ureter model included stenosis at the distal ureter near the ureterovesical junction and the other did not. We used conventional DJS and renovated 5- and 6-Fr soft DJS for ureter stones and 6-, 7-, and 8.5-Fr hard DJS for tumors. The DJS comprised holes in the upper, middle, or lower one-third of the shaft (length, 24 cm; 2-cm-diameter coils at both ends). More holes were created along the shaft based on the ureteral disease location. Conventional DJS had holes spaced 1 cm apart along the shaft. Renovated DJS had holes spaced 1 cm apart along the shaft with 0.5-cm intervals on the upper, middle, or lower one-third of the shaft. Urine flow was evaluated. RESULTS: As the DJS diameter increased, the flow rate decreased. The flow rates of DJS with holes in the lower shaft were relatively lower than those of conventional DJS and DJS with holes in the upper and middle shafts. In the ureter model without stenosis, 6-, 7-, and 8.5-Fr renovated stents exhibited significantly higher flow rates than conventional stents. In the ureter model with stenosis, 5-, 6-, 7-, and 8.5-Fr renovated stents did not exhibit significantly higher flow rates than conventional stents. CONCLUSION: Renovated stents and conventional stents did not exhibit significant differences in urine flow with stenosis.

Analysis of epoxy composites reinforced with jute, banana, and coconut fibers and enhanced with Rubik's layer: Tensile, bending, and impact performance evaluation.

This research paper presents a comprehensive analysis of epoxy composites fortified with natural fibers such as jute, banana, and coconut, further augmented by the incorporation of Rubik's layer, aimed at evaluating their mechanical performance in terms of tensile, bending, and impact properties. As sustainable alternatives to traditional reinforcement materials, these natural fibers offer the advantage of low environmental impact, renewability, and biodegradability. The Rubik's layer, known for its three-dimensional interlocking structure, holds promise in enhancing composite properties due to its unique geometry and material characteristics. The study involves the fabrication of composite specimens through a systematic layering process, varying the composition of natural fibers and Rubik's layer. A comprehensive experimental campaign is conducted to assess the tensile strength, bending modulus, and impact resistance of the resultant composites. The results are systematically compared against those of pristine epoxy composites to ascertain the influence of the added reinforcements and enhancement layer. The findings reveal distinctive trends in mechanical behavior based on the type and proportion of natural fibers employed. Notably, the jute-reinforced composites exhibit commendable tensile and bending properties, while banana and coconut reinforcements contribute to improved impact resistance. The introduction of the Rubik's layer further refines these properties, with discernible variations based on its placement within the composite structure. This paper offers valuable insights into the multifaceted impact of natural fiber reinforcements and Rubik's layer incorporation on epoxy composites. The systematic evaluation of mechanical attributes provides a comprehensive understanding of the synergistic effects among these constituents. As the demand for sustainable and high-performance materials escalates, this research contributes to the growing body of knowledge on composite design, catering to diverse engineering applications that prioritize mechanical excellence and ecological responsibility.

DFT Insights into MAX Phase Borides Hf2AB [A = S, Se, Te] in Comparison with MAX Phase Carbides Hf2AC [A = S, Se, Te].

In this work, density functional theory (DFT)-based calculations were performed to compute the physical properties (structural stability, mechanical behavior, and electronic, thermodynamic, and optical properties) of synthesized MAX phases Hf2SB, Hf2SC, Hf2SeB, Hf2SeC, and Hf2TeB and the as-yet-undiscovered MAX carbide phase Hf2TeC. Calculations of formation energy, phonon dispersion curves, and elastic constants confirmed the stability of the aforementioned compounds, including the predicted Hf2TeC. The obtained values of lattice parameters, elastic constants, and elastic moduli of Hf2SB, Hf2SC, Hf2SeB, Hf2SeC, and Hf2TeB showed fair agreement with earlier studies, whereas the values of the aforementioned parameters for the predicted Hf2TeC exhibit a good consequence of B replacement by C. The anisotropic mechanical properties are exhibited by the considered MAX phases. The metallic nature and its anisotropic behavior were revealed by the electronic band structure and density of states. The analysis of the thermal properties-Debye temperature, melting temperature, minimum thermal conductivity, and Grüneisen parameter-confirmed that the carbide phases were more suited than the boride phases considered herein. The MAX phase's response to incoming photons further demonstrated that they were metallic. Their suitability for use as coating materials to prevent solar heating was demonstrated by the reflectivity spectra. Additionally, this study demonstrated the impact of B replacing C in the MAX phases.

A Scalable Microstructure Photonic Coating Fabricated by Roll-to-Roll "Defects" for Daytime Subambient Passive Radiative Cooling.

The deep space's coldness (∼4 K) provides a ubiquitous and inexhaustible thermodynamic resource to suppress the cooling energy consumption. However, it is nontrivial to achieve subambient radiative cooling during daytime under strong direct sunlight, which requires rational and delicate photonic design for simultaneous high solar reflectivity (>94%) and thermal emissivity. A great challenge arises when trying to meet such strict photonic microstructure requirements while maintaining manufacturing scalability. Herein, we demonstrate a rapid, low-cost, template-free roll-to-roll method to fabricate spike microstructured photonic nanocomposite coatings with Al2O3 and TiO2 nanoparticles embedded that possess 96.0% of solar reflectivity and 97.0% of thermal emissivity. When facing direct sunlight in the spring of Chicago (average 699 W/m2 solar intensity), the coatings show a radiative cooling power of 39.1 W/m2. Combined with the coatings' superhydrophobic and contamination resistance merits, the potential 14.4% cooling energy-saving capability is numerically demonstrated across the United States.

Nontoxic Cross-Linked Graphitic Carbon Nitride-Alginate-Based Biodegradable Transparent Films for UV and High-Energy Blue Light Shielding.

Flexible, transparent, and biodegradable films that can shield dangerous UV and high-energy blue light (HEBL) are high in demand to satisfy the ever-increasing expectations for environmental sustainability. To achieve this goal, biopolymer alginate is an excellent choice that has an outstanding film-forming ability. However, alginate has the limitation of poor UV and HEBL blocking ability. Thus, in this study, UV and HEBL blocker graphitic carbon nitride (g-C3N4) was incorporated in alginate films to enhance the compatibility, applicability, and durability. The ATR-FTIR, TGA, DTG, and FE-SEM results indicated that the composite film formation was due to hydrogen bonding, and the composite films revealed synergistic properties of alginate and g-C3N4. Though the incorporation of g-C3N4 in films enhanced the mechanical and thermal stabilities of the films, the films were still flexible. The UV-visible transmittance characterization confirmed that the prepared films could block both UV and HEBL radiation while maintaining transparency in visible regions. In experiments involving only 2 wt % g-C3N4, nearly 90% of UV (200-400 nm) and 95% of HEBL (400-450 nm) irradiation were blocked. Additionally, the inclusion of g-C3N4 also facilitated the biodegradation process of composite films. Moreover, after 6 months, the composite films exhibited excellent UV and HEBL shielding with excellent mechanical durability.

Spatio-temporal variation of land use and land cover changes and their impact on land surface temperature: A case of Kutupalong Refugee Camp, Bangladesh.

Environmental degradation can be predicted and managed in a sustainable manner by the perodic analysis of the Land Use/Land Cover (LULC) change pattern, which not only helps to revitalize the environment but also helps to improve future land-use policies. With the Rohingya influx in 2017, the Kutupalong Mega Camp area in Bangladesh is at a severe risk of environmental degradation as the area is experiencing remarkable LULC change. The aim of this research is to illustrate the LULC change in the Kutupalong Mega Camp before and after the refugee influx, as well as its impact on the surrounding environment because of this change. The spatial and temporal variation of the LULC is analyzed from the classified multi-temporal Landsat images for years-2015, 2018, and 2021. The study reveals gradual decrease in forest cover of the area, which is replaced by the increasing human settlements. The study found an inverse relation between the refugee influx and the vegetation cover, where a positive relation to the bare land and settlement exists. The area experienced about ten times increase in human settlements during 2015-2021, which resulted deforestation of surrounding forest cover. Between 2015 to 2021, 74 % of forest cover of the studied area has been cleaned up for newer settlements, with an increase of wetland to meet the needs of increasing refugee population which has made the scenario worse. We also noticed an increase of Land Surface Temperature (LST) within a short period, where the average temperature increase rate is 0.06% during 2015-2018 and 0.01% during 2018-2021. The ecosystem, wild-habitat, and the thermal environment has been disturbed to a great extent due to this drastic change of forest cover mostly by the increasing anthropogenic activities in this area. The study represents the present scenario in comparison to its natural setting just a few years ago, and may serve as a guidance for the concerned authorities and international humanitarian organizations to develop a sustainable, comprehensive, and environment-friendly land management plan in order to protect the surrounding forest-ecology as well as the humanitarian works.

Effect of Pressure on the Superconducting Transition Temperature and Physical Properties of CaPd2P2: A DFT Investigation.

CaPd2P2 is a recently reported superconducting material belonging to the well-known ThCr2Si2-type family. First-principles density functional theory calculations have been carried out to investigate the structural, mechanical, thermophysical, optical, electronic, and superconducting properties of the CaPd2P2 compound under pressure. To the best of our knowledge, this is the first theoretical approach to studying the pressure effect on the fundamental physical and superconducting properties of CaPd2P2. It is mechanically stable under the studied pressures. The applied hydrostatic pressure reveals a noticeable impact on elastic moduli of CaPd2P2. It exhibits ductile nature under the studied pressure. Significant anisotropic behavior of the compound is revealed with/without pressure. The study of melting temperature shows that the compound has a higher melting temperature, which increases with the increasing applied pressure. The investigation of the electronic properties strongly supports the optical function analysis. The reflectivity as well as the absorption spectra shifts to higher energy with the increasing applied pressure. The pressure-dependent behavior of the superconducting transition temperature, T c, is revealed with a pressure-induced increasing trend in Debye temperature.

The impact of wood dust on pulmonary function and blood immunoglobulin E, erythrocyte sedimentation rate, and C- reactive protein: A cross-sectional study among sawmill workers in Tangail, Bangladesh.

Background and Aims: Occupational exposure to wood dust leads to lung function abnormalities that are prominent causes of morbidity and disability of sawmill workers. The adverse respiratory effects of wood dust in sawmills have not been studied thoroughly in Bangladesh. This study aimed to investigate the effect of wood dust on the respiratory health of sawmill workers compared to controls as well as to determine the association of wood dust-exposing effects with inflammatory blood biomarkers, such as immunoglobulin E (IgE), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP). Methods: This cross-sectional study included 100 sawmill workers from 25 distinct sawmills in various areas of Tangail, Bangladesh as well as 100 healthy volunteers who were adopted as a control group. Questionaries' survey and pulmonary function tests were performed face to face. Furthermore, after performing lung function tests, blood was drawn for further IgE, ESR, and CRP analyses. Results: Respiratory symptoms including breathlessness (32%), coughing (39%), sneezing (43%), chest tightness (30%), and itching (40%) were significantly higher in sawmill workers compared with control. Besides, sawmill workers' exposure to wood dust revealed a significantly lower level of spirometry parameters (forced vital capacity ​​​​​[FVC], FVC (%), forced expiratory volume in 1 s [FEV1], FEV1 (%), peak expiratory flow [PEF], PEF (%), FEV1/FVC (%), FEF25, FEF75, and FEF2575) compared with control and these spirometry parameters decreased with the increasing length of service. Moreover, a significantly higher level of IgE was observed in sawmill workers (290.90 ± 39.49) than in the control (120.95 ± 23.00). The high level of IgE suggests that the lower pulmonary function may be linked to allergic responses to wood dust among sawmill workers. Conclusion: This study suggested that exposure to wood dust can cause impairment of respiratory function along with high IgE levels.

Metformin treatment reverses high fat diet- induced non-alcoholic fatty liver diseases and dyslipidemia by stimulating multiple antioxidant and anti-inflammatory pathways.

PURPOSE: This current study investigated the effect of metformin treatment on hepatic oxidative stress and inflammation associated with nonalcoholic fatty liver disease (NADLD) in high fat diet (HFD) fed rats. METHOD: Wistar rats were fed with a HFD or laboratory chow diet for 8 weeks. Metformin was administered orally at a dose of 200 mg/kg. Body weight, food and water intake were recorded on daily basis. Oral glucose tolerance test (OGTT), biochemical analysis and histological examinations were conducted on plasma and tissue samples. Antioxidant and anti-inflammatory mRNA expression was analyzed using reverse transcription polymeric chain reaction (RT-PCR). RESULTS: Metformin treatment for 8 weeks prevented HFD-induced weight gain and decreased fat deposition in HFD fed rats. Biochemical analysis revealed that metformin treatment significantly attenuated nitro-oxidative stress markers malondialdehyde (MDA), advanced protein oxidation product (APOP), and excessive nitric oxide (NO) levels in the liver of HFD fed rats. Gene expression analysis demonestrated that metformin treatment was associated with an enhanced expression of antioxidant genes such as Nrf-2, HO-1, SOD and catalase in liver of HFD fed rats. Metformin treatment also found to modulate the expression of fat metabolizing and anti-inflammatory genes including PPAR--γ, C/EBP-α, SREBP1c, FAS, AMPK and GLUT-4. Consistent with the biochemical and gene expression data, the histopathological examination unveiled that metformin treatment attenuated inflammatory cells infiltration, steatosis, hepatocyte necrosis, collagen deposition, and fibrosis in the liver of HFD fed rats. CONCLUSION: In conclusion, this study suggests that metformin might be effective in the prevention and treatment of HFD-induced steatosis by reducing hepatic oxidative stress and inflammation in the liver.