4-Hydr­oxy-1-oxo-1,2-dihydro­phthalazine-6,7-dicarboxylic acid dihydrate

In the crystal structure of the title compound, C10H6N2O6·2H2O, the OH and NH groups each serve as a hydrogen-bond donor to one acceptor site whereas the water mol­ecules each serve as a hydrogen-bond donor to two acceptor sites. The hydrogen-bonding scheme gives rise to a three-dimensional network

[2,6-Bis(p-tol­ylimino­meth­yl)pyridine-κ3 N,N′,N′′]dichloridocopper(II)

The title compound, [CuCl2(C21H19N3)], lies on a twofold rotation axis that passes through the Npyrid­yl—Cu bond; this symmetry element relates one half of the organic ligand to the other as well as one Cl ligand to the other. The three N atoms span the axial–equatorial–axial sites of the trigonal-bipyramidal coordination polyhedron; the geometry of the CuII atom is 31% distorted from trigonal-bipyramidal (towards square-pyramidal along the Berry pseudorotation pathway)

Realization of Zero-Refractive-Index Lens with Ultralow Spherical Aberration

Optical complex materials offer unprecedented opportunity to engineer fundamental band dispersion which enables novel optoelectronic functionality and devices. Exploration of photonic Dirac cone at the center of momentum space has inspired an exceptional characteristic of zero-index, which is similar to zero effective mass in fermionic Dirac systems. Such all-dielectric zero-index photonic crystals provide an in-plane mechanism such that the energy of the propagating waves can be well confined along the chip direction. A straightforward example is to achieve the anomalous focusing effect without longitudinal spherical aberration, when the size of zero-index lens is large enough. Here, we designed and fabricated a prototype of zero-refractive-index lens by comprising large-area silicon nanopillar array with plane-concave profile. Near-zero refractive index was quantitatively measured near 1.55 um through anomalous focusing effect, predictable by effective medium theory. The zero-index lens was also demonstrated to perform ultralow longitudinal spherical aberration. Such IC compatible device provides a new route to integrate all-silicon zero-index materials into optical communication, sensing, and modulation, and to study fundamental physics on the emergent fields of topological photonics and valley photonics.Comment: 14 pages, 4 figure

[2,6-Bis(6-methyl­quinolin-2-yl)pyridine-κ3 N,N′,N′′]dichloridoiron(II)

In the mol­ecule of the title compound, [FeCl2(C25H19N3)], the three N atoms span the axial–equatorial–axial sites of the trigonal-bipyramidal coordination polyhedron; the geometry of the FeII atom is 32% distorted from trigonal-bipyramidal (towards square-pyramidal along the Berry pseudorotation pathway). One of the Cl atoms is disordered over two positions in a 0.938 (11):0.062 (11) ratio. Inter­molecular C—H⋯Cl hydrogen bonding occurs in the crystal structure

[2,6-Bis(6-methyl­quinolin-2-yl)pyridine-κ3 N,N′,N′′]dichloridomanganese(II)

In the mol­ecule of the title compound, [MnCl2(C25H19N3)], the three N atoms span the axial–equatorial–axial sites of the trigonal-bipyramidal coordination polyhedron; the geometry of the MnII atom is 34% distorted from trigonal-bipyramidal (towards square-pyramidal along the Berry pseudorotation pathway). One of the Cl atoms is disordered over two positions in a 0.82 (3):0.18 (3) ratio. Weak inter­molecular C—H⋯Cl hydrogen bonding occurs in the crystal structure

{2,6-Bis[(4-bromo­phen­yl)imino­meth­yl]pyridine-κ3 N,N′,N′′}trichlorido­chromium(III)

In the title compound, [CrCl3(C19H13Br2N3)], the Cr3+ ion is coordinated by the tridentate 2,6-bis­[(4-bromo­phen­yl)imino­meth­yl]pyridine Schiff base ligand in a fac-octa­hedral geometry. The dihedral angles between the pyridine and benzene rings are 23.9 (6) and 70.7 (1)°

Inference of drowning sites using bacterial composition and random forest algorithm

Diagnosing the drowning site is a major challenge in forensic practice, particularly when corpses are recovered from flowing rivers. Recently, forensic experts have focused on aquatic microorganisms, including bacteria, which can enter the bloodstream during drowning and may proliferate in corpses. The emergence of 16S ribosomal RNA gene (16S rDNA) amplicon sequencing has provided a new method for analyzing bacterial composition and has facilitated the development of forensic microbiology. We propose that 16S rDNA amplicon sequencing could be a useful tool for inferring drowning sites. Our study found significant differences in bacterial composition in different regions of the Guangzhou section of the Pearl River, which led to differences in bacteria of drowned rabbit lungs at different drowning sites. Using the genus level of bacteria in the lung tissue of drowned rabbits, we constructed a random forest model that accurately predicted the drowning site in a test set with 100% accuracy. Furthermore, we discovered that bacterial species endemic to the water were not always present in the corresponding drowned lung tissue. Our findings demonstrate the potential of a random forest model based on bacterial genus and composition in drowned lung tissues for inferring drowning sites

Screening Level of PAHs in Sediment Core from Lake Hongfeng, Southwest China

Using data from a 25-year retrospective of polycyclic aromatic hydrocarbons (PAHs) in sediment core from Lake Hongfeng, Southwest China, their possible sources and potential toxicologic significance were investigated. The total PAH concentrations (16 priority PAHs as proposed by the United States Environmental Protection Agency) in sediments ranged from 2936.1 to 5282.3 ng/g and gradually increased from the analyzed deeper sediments to surface sediments. PAHs were dominated by low molecular-weight components, especially phenanthrene (PHEN) and fluorene (FLU). However, a significantly increased number of high molecular-weight (HMW) PAHs was found in upper segments. The temporal trends of individual PAH species suggest that there may have been a change in energy use from low- to high-temperature combustion, especially after approximately 2001. PAH input to Lake Hongfeng originated mainly from domestic coal combustion and biomass burning, whereas fuel combustion characteristics have also been found in recent years. Sediment-quality assessment implied that potential adverse biologic impact could be a probability for most low-ring PAHs (including naphthalene, acenaphthylene, acenaphthylene, FLU, PHEN, and anthracene). Nevertheless, more concern should be paid to HMW PAHs in the future due to their rapidly increasing trends in upper sediments. Because only one core was analyzed in this study, more work is needed to confirm the sources and toxicity of PAHs in Lake Hongfeng

Identification of Enriched Driver Gene Alterations in Subgroups of Non-Small Cell Lung Cancer Patients Based on Histology and Smoking Status

BACKGROUND: Appropriate patient selection is needed for targeted therapies that are efficacious only in patients with specific genetic alterations. We aimed to define subgroups of patients with candidate driver genes in patients with non-small cell lung cancer. METHODS: Patients with primary lung cancer who underwent clinical genetic tests at Guangdong General Hospital were enrolled. Driver genes were detected by sequencing, high-resolution melt analysis, qPCR, or multiple PCR and RACE methods. RESULTS: 524 patients were enrolled in this study, and the differences in driver gene alterations among subgroups were analyzed based on histology and smoking status. In a subgroup of non-smokers with adenocarcinoma, EGFR was the most frequently altered gene, with a mutation rate of 49.8%, followed by EML4-ALK (9.3%), PTEN (9.1%), PIK3CA (5.2%), c-Met (4.8%), KRAS (4.5%), STK11 (2.7%), and BRAF (1.9%). The three most frequently altered genes in a subgroup of smokers with adenocarcinoma were EGFR (22.0%), STK11 (19.0%), and KRAS (12.0%). We only found EGFR (8.0%), c-Met (2.8%), and PIK3CA (2.6%) alterations in the non-smoker with squamous cell carcinoma (SCC) subgroup. PTEN (16.1%), STK11 (8.3%), and PIK3CA (7.2%) were the three most frequently enriched genes in smokers with SCC. DDR2 and FGFR2 only presented in smokers with SCC (4.4% and 2.2%, respectively). Among these four subgroups, the differences in EGFR, KRAS, and PTEN mutations were statistically significant. CONCLUSION: The distinct features of driver gene alterations in different subgroups based on histology and smoking status were helpful in defining patients for future clinical trials that target these genes. This study also suggests that we may consider patients with infrequent alterations of driver genes as having rare or orphan diseases that should be managed with special molecularly targeted therapies