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In patients with erythropoietic protoporphyria, sensitivity to the sun leads to pain and compromised quality of life. In two clinical trials, one in Europe and one in the United States, a peptide analogue of an α-melanocyte–stimulating hormone alleviated symptoms. Erythropoietic protoporphyria is a rare, autosomal recessive inborn error of metabolism that typically manifests in early childhood as severe painful photosensitivity. The photosensitivity results from accumulated protoporphyrin in erythroid cells and tissues because of the decreased activity of ferrochelatase, the heme biosynthetic enzyme that inserts iron into protoporphyrin to form heme. 1 – 4 An X-linked form of erythropoietic protoporphyria 5 , 6 that accounts for 2 to 10% of cases results from a gain of function of erythroid-specific aminolevulinic acid synthase 2. Pathophysiologically, protoporphyrin is released from erythroid cells into the circulation, gains access to the vascular endothelium and liver, and is excreted . . .

In this work, we introduce a novel approach to model the rain and fog effect on the light detection and ranging (LiDAR) sensor performance for the simulation-based testing of LiDAR systems. The proposed methodology allows for the simulation of the rain and fog effect using the rigorous applications of the Mie scattering theory on the time domain for transient and point cloud levels for spatial analyses. The time domain analysis permits us to benchmark the virtual LiDAR signal attenuation and signal-to-noise ratio (SNR) caused by rain and fog droplets. In addition, the detection rate (DR), false detection rate (FDR), and distance error derror of the virtual LiDAR sensor due to rain and fog droplets are evaluated on the point cloud level. The mean absolute percentage error (MAPE) is used to quantify the simulation and real measurement results on the time domain and point cloud levels for the rain and fog droplets. The results of the simulation and real measurements match well on the time domain and point cloud levels if the simulated and real rain distributions are the same. The real and virtual LiDAR sensor performance degrades more under the influence of fog droplets than in rain.

Cutaneous melanoma causes 55 500 deaths annually. The incidence and mortality rates of the disease differ widely across the globe depending on access to early detection and primary care. Once melanoma has spread, this type of cancer rapidly becomes life-threatening. For more than 40 years, few treatment options were available, and clinical trials during that time were all unsuccessful. Over the past 10 years, increased biological understanding and access to innovative therapeutic substances have transformed advanced melanoma into a new oncological model for treating solid cancers. Treatments that target B-Raf proto-oncogene serine/threonine-kinase (BRAF)V600 (Val600) mutations using selected BRAF inhibitors combined with mitogen-activated protein kinase inhibitors have significantly improved response and overall survival. Furthermore, advanced cutaneous melanoma has developed into a prototype for testing checkpoint-modulating agents, which has increased hope for long-term tumour containment and a potential cure. These expectations have been sustained by clinical success with targeted agents and antibodies that block programmed cell-death protein 1 in locoregional disease, which induces prolongation of relapse-free, distant-metastasis-free, and overall survival times.

Hierarchical porous TiO photocatalytic nanomaterials were fabricated by impregnation and calcination using a peanut shell biotemplate, and TiO /BiFeO composite nanomaterials with different doping amounts were fabricated using hydrothermal synthesis. The micromorphology, structure, element composition and valence state of the photocatalyst were analyzed using a series of characterization methods, including X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), BET surface area (BET), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance (UV-vis), fluorescence spectroscopy (PL) and other technological means. Finally, the degradation mechanism and efficiency of BiFeO composite photocatalyst on the target pollutant triclosan were analyzed using a xenon lamp to simulate sunlight. The results showed that TiO /BiFeO catalyst fabricated using a peanut shell biotemplate has a specific surface area of 153.64 m /g, a band gap of 1.92 eV, and forms heterostructures. The optimum doping amount of TiO /BiFeO catalyst was 1 mol/mol, and the degradation rate was 81.2%. The main active substances degraded were ·O and ·OH. The degradation process measured is consistent with the pseudo-first-order kinetic model.

The presence of pharmaceutical compounds in the environment is a reality that calls for more efficient water treatment technologies. Photocatalysis is a powerful technology available but the high energy costs associated with the use of UV irradiation hinder its large scale implementation. More sustainable and cheaper photocatalytic processes can be achieved by improving the sunlight harvesting and the synthesis of semiconductor/carbon composites has proved to be a promising strategy. Carbamazepine, diclofenac, and sulfamethoxazole were selected as target pharmaceuticals due to their recalcitrant behavior during conventional wastewater treatment and persistence in the environment, as properly reviewed. The literature data on the photocatalytic removal of carbamazepine, diclofenac, and sulfamethoxazole by semiconductor/carbon materials was critically revised to highlight the role of the carbon in the enhanced semiconductor performance under solar irradiation. Generally it was demonstrated that carbon materials induce red-shift absorption and they contribute to more effective charge separation, thus improving the composite photoactivity. Carbon was added as a dopant (C-doping) or as support or doping materials (i.e., nanoporous carbons, carbon nanotubes (CNTs), graphene, and derived materials, carbon quantum dots (CQDs), and biochars) and in the large majority of the cases, TiO2 was the semiconductor tested. The specific role of carbon materials is dependent on their properties but even the more amorphous forms, like nanoporous carbons or biochars, allow to prepare composites with improved properties compared to the bare semiconductor. The self-photocatalytic activity of the carbon materials was also reported and should be further explored. The removal and mineralization rates, as well as degradation pathways and toxicity of the treated solutions were also critically analyzed.

Neutron Star Interior Composition Explorer has a comparatively low background rate, but it is highly variable, and its spectrum must be predicted using measurements unaffected by the science target. We describe an empirical, three-parameter model based on observations of seven pointing directions that are void of detectable sources. Two model parameters track different types of background events, while the third is used to predict a low-energy excess tied to observations conducted in sunlight. An examination of 3556 good time intervals (GTIs), averaging 570 s, yields a median rate (0.4–12 keV; 50 detectors) of 0.87 c s−1, but in 5% (1%) of cases, the rate exceeds 10 (300) c s−1. Model residuals persist at 20%–30% of the initial rate for the brightest GTIs, implying one or more missing model parameters. Filtering criteria are given to flag GTIs likely to have unsatisfactory background predictions. With such filtering, we estimate a detection limit, 1.20 c s−1 (3σ, single GTI) at 0.4–12 keV, equivalent to 3.6 × 10−12 erg cm−2 s−1 for a Crab-like spectrum. The corresponding limit for soft X-ray sources is 0.51 c s−1 at 0.3–2.0 keV, or 4.3 × 10−13 erg cm−2 s−1 for a 100 eV blackbody. These limits would be four times lower if exploratory GTIs accumulate 10 ks of data after filtering at the level prescribed for faint sources. Such filtering selects background GTIs 85% of the time. An application of the model to a 1 s timescale makes it possible to distinguish source flares from possible surges in the background.

Achieving both high efficiency and long-term stability is the key to the commercialization of perovskite solar cells (PSCs) 1 , 2 . However, the diversity of perovskite (ABX 3 ) compositions and phases makes it challenging to fabricate high-quality films 3 – 5 . Perovskite formation relies on the reaction between AX and BX 2 , whereas most conventional methods for film-growth regulation are based solely on the interaction with the BX 2 component. Herein, we demonstrate an alternative approach to modulate reaction kinetics by anion–π interaction between AX and hexafluorobenzene (HFB). Notably, these two approaches are independent but work together to establish ‘dual-site regulation’, which achieves a delicate control over the reaction between AX and BX 2 without unwanted intermediates. The resultant formamidinium lead halides (FAPbI 3 ) films exhibit fewer defects, redshifted absorption and high phase purity without detectable nanoscale δ phase. Consequently, we achieved PSCs with power conversion efficiency (PCE) up to 26.07% for a 0.08-cm 2 device (25.8% certified) and 24.63% for a 1-cm 2 device. The device also kept 94% of its initial PCE after maximum power point (MPP) tracking for 1,258 h under full-spectrum AM 1.5 G sunlight at 50 ± 5 °C. This method expands the range of chemical interactions that occur in perovskite precursors by exploring anion–π interactions and highlights the importance of the AX component as a new and effective working site to improved photovoltaic devices with high quality and phase purity. The use of anion–π interactions during perovskite film formation is shown to give better quality perovskite layers with high phase purity, leading to improved photovoltaic devices with high power conversion efficiency.

Research on advanced materials for environmental remediation and pollutant degradation is rapidly progressing because of their numerous applications. Biochar is an excellent material support for the catalytic activity of bismuth ferrite (BiFeO3), which is one of the best perovskite-based photocatalysts in this work for diverse pollutant degradation when exposed to direct sunlight. Biochar was produced by pyrolyzing oil palm empty fruit bunches (OPEFBs) and then integrate with BiFeO3 in the presence of cross-linked chitosan to create a BFO/biochar coupled magnetic photocatalyst (CBB). This research was conducted to examine the performance of the photocatalytic activity of CBB towards the degradation of ciprofloxacin antibiotics. To determine the optimal condition, two operational parameters that are photocatalyst dosage and initial pollutant concentrations, were evaluated. The results of the powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope-energy dispersive X-ray (SEM-EDX) analyses confirmed the high purity of the rhombohedral BiFeO3 with a high surface area, as well as the successful coupling of BiFeO3 and biochar at a ratio of 1:1. The most effective conditions for the various variables are 1.5 g/L CBB dosage at 10 ppm with 77.08% photodegradation under direct sunlight for 2 h. Further, a pseudo-first-order kinetic reaction was followed and observed with decreasing k values as the initial concentration increased. This shows that the system performs best at low concentrations. This finding confirms that the catalytic parameters improved the efficiency of photocatalysts with biochar assistance in removing antibiotic pollutants.