Power Amplification and Coherent Combination Techniques for Terahertz Quantum Cascade Lasers

Power amplification and coherent combination are important ways to improve the output power and beam quality of single‐mode terahertz quantum cascade lasers (THz QCLs). Up to date, the tapered waveguide is the most convenient way to amplify the power of THz QCLs. The self‐focusing effect in tapered THz QCLs induces non‐monotonic behaviours of the peak power and far‐field beam divergence, which lead to the existence of optimal structural parameters. The surface and lateral grating techniques have also been employed in tapered THz QCLs to further improve the spectral purity. For coherent combinations, the progress of facet‐emitting phase‐locked arrays of THz QCLs is still limited due to both the lack of the understanding of dynamics of coupled QCLs and the difficulties in designing high‐performance coupled waveguides. We will briefly review the developments of coherent arrays of THz QCLs and present a design of monolithic QCL arrays with common coupled cavity to achieve the optical mutual injection, which may provide a new way for coherent combination of THz QCLs

A review on the chemical constituents and pharmacological efficacies of Lindera aggregata (Sims) Kosterm

Lindera aggregata (Sims) Kosterm. (L. aggregata), which belongs to the genus Lindera in the family Lauraceae, is widely distributed in Asia and the temperate, tropical regions of North America. Its roots and leaves have been used for thousands of years as traditional Chinese medicine and/or functional food. To further explore its underlying nutritional value, this review provided a comprehensive insight into chemical constituents and pharmacological effects on L. aggregata. The phytochemical investigation of different parts of L. aggregata led to the identification of up to 349 components belonging to sesquiterpenoids, alkaloids, flavonoids, essential oils, and other compounds. Among them, sesquiterpenoids, flavonoids, and alkaloids are assessed as representative active ingredients of L. aggregata. A wide variety of pharmacological effects of L. aggregata, such as anti-hyperlipidemic, anti-tumor, anti-inflammatory, analgesic, and anti-oxidant, have been proved in vitro and in vivo. In summary, this review aims to provide a scientific basis and reference for further research and utilization of L. aggregata and lay the foundation for developing functional foods with potential active ingredients for the prevention and management of related diseases

The Mitogen-activated Protein Kinase Phosphatases PAC1, MKP-1, and MKP-2 Have Unique Substrate Specificities and Reduced Activity in Vivo toward the ERK2 sevenmaker Mutation

Mitogen-activated protein (MAP) kinases can be grouped into three structural families, ERK, JNK, and p38, which are thought to carry out unique functions within cells. We demonstrate that ERK, JNK, and p38 are activated by distinct combinations of stimuli in T cells that simulate full or partial activation through the T cell receptor. These kinases are regulated by reversible phosphorylation on Tyr and Thr, and the dual specific phosphatases PAC1 and MKP-1 previously have been implicated in the in vivo inactivation of ERK or of ERK and JNK, respectively. Here we characterize a new MAP kinase phosphatase, MKP-2, that is induced in human peripheral blood T cells with phorbol 12-myristate 13-acetate and is expressed in a variety of nonhematopoietic tissues as well. We show that the in vivo substrate specificities of individual phosphatases are unique. PAC1, MKP-2, and MKP-1 recognize ERK and p38, ERK and JNK, and ERK, p38, and JNK, respectively. Thus, individual MAP kinase phosphatases can differentially regulate the potential for cross-talk between the various MAP kinase pathways. A hyperactive allele of ERK2 (D319N), analogous to the Drosophila sevenmaker gain-of-function mutation, has significantly reduced sensitivity to all three MAP kinase phosphatases in vivo

Age-related differences in risk factors, clinical characteristics, and outcomes for intracerebral hemorrhage

Background and purposeIntracerebral hemorrhage (ICH) is a severe form of stroke that remains understudied in the young adults. We aimed to investigate the clinical presentation, and risk factors associated with ICH in this age group and compare them to older patients.MethodsOur study included ICH patients admitted between March 2016 and December 2021 in the First Affiliated Hospital of Chongqing Medical University from our ongoing prospective cohort database. Demographic characteristics, etiology, risk factors, and clinical outcomes were compared between elderly and young patients. Furthermore, logistic regression analysis was employed to explore risk factors associated with the functional outcome at 3-months.ResultsWe selected 1,003 patients (mean age, 59.9 ±13.8 years old), 746 (74.4%) patients were aged >50 years. The logistic regression analysis showed young patients have a higher proportion of secondary ICH, higher white blood cell count and higher body mass index (BMI), but less diabetes mellitus. Of all patients, predictors of 3-month functional independence was first-ever ICH and age ≤50 years. The history of nephropathy and stroke, higher baseline NIHSS score, larger hematoma volume, and the presence of hydrocephalus were associated with poor outcomes. And the white blood cell count could significantly influence the prognosis among young ICH patients. Three-month functional outcome based on modified Rankin scale score was better in young patients than the elderly (OR, 1.232; 95% CI, 1.095–1.388; p < 0.001).ConclusionsThe highest incidence of ICH occurs in the age groups of 50–59 and 60–69. ICH in young adults had higher white blood cell and BMI compared to the elderly, and differs in etiological distribution. The young patients also had similar short-term mortality but more favorable functional outcomes than the elderly. Furthermore, NIHSS score and larger hematoma volumes were associated with poor outcome in all patients

Identification of Sequence Variants in Genetic Disease-Causing Genes Using Targeted Next-Generation Sequencing

Identification of gene variants plays an important role in research on and diagnosis of genetic diseases. A combination of enrichment of targeted genes and next-generation sequencing (targeted DNA-HiSeq) results in both high efficiency and low cost for targeted sequencing of genes of interest.To identify mutations associated with genetic diseases, we designed an array-based gene chip to capture all of the exons of 193 genes involved in 103 genetic diseases. To evaluate this technology, we selected 7 samples from seven patients with six different genetic diseases resulting from six disease-causing genes and 100 samples from normal human adults as controls. The data obtained showed that on average, 99.14% of 3,382 exons with more than 30-fold coverage were successfully detected using Targeted DNA-HiSeq technology, and we found six known variants in four disease-causing genes and two novel mutations in two other disease-causing genes (the STS gene for XLI and the FBN1 gene for MFS) as well as one exon deletion mutation in the DMD gene. These results were confirmed in their entirety using either the Sanger sequencing method or real-time PCR.Targeted DNA-HiSeq combines next-generation sequencing with the capture of sequences from a relevant subset of high-interest genes. This method was tested by capturing sequences from a DNA library through hybridization to oligonucleotide probes specific for genetic disorder-related genes and was found to show high selectivity, improve the detection of mutations, enabling the discovery of novel variants, and provide additional indel data. Thus, targeted DNA-HiSeq can be used to analyze the gene variant profiles of monogenic diseases with high sensitivity, fidelity, throughput and speed

Oxygen Nanobubble-Loaded Biochars Mitigate Copper Transfer from Copper-Contaminated Soil to Rice and Improve Rice Growth

13 Pág.Copper (Cu)-contaminated paddy soil has caused substantial concerns for human health through biomagnification in the soil-rice-human chain. In this study, oxygen nanobubble-loaded biochars (ONBC), including pyrochars (NPC) and hydrochars (NHC), were used to amend Cu-contaminated paddy soils and reduce rice Cu toxicity. The ONBC amendment improved the rhizospheric redox potential and dissolved oxygen concentration via slow, continuous oxygen release, promoting root iron plaque formation and effectively inhibiting root Cu influx. Moreover, the ONBC amendment improved soil microbial diversity. The abundance of bacterial genes involved in cytosolic Cu complexation and Cu export to the periplasm space for Cu stabilization markedly improved. The sequestered Cu in root iron plaque and soil bacteria inhibited Cu influx into the shoots to avoid Cu overaccumulation in the edible parts. This was reflected by the Cu content decreasing by 1.91-fold and 2.38-fold in shoots under NPC and NHC treatments, respectively. Furthermore, the improved oxygen-enriched rhizosphere environment via the ONBC amendment promoted root activity and the abundance of bacterial genes involved in nutrients mineralization, further promoting shoot biomass by 1.46-fold and 2.29-fold under NPC and NHC treatments, respectively. This study proposes an environmentally friendly strategy to mitigate Cu transfer from soil to crops and improve crop productivity.This work was supported by the National Key Research and Development Program of China (021YFD1700805), Natural Science Foundation of Jiangsu Province (BK20221428), Agriculture Research System of Shanghai, China (202203), Yunnan Branch of China National Tobacco Corporation (2022530000241022), 333 High-level Talents Training Project of Jiangsu Province (2022-3-23-083). and USDA Hatch program (MAS 00549).Peer reviewe

Recent Advances on the Strategies to Stabilize the α-Phase of Formamidinium Based Perovskite Materials

Perovskite solar cells (PSC) are considered promising next generation photovoltaic devices due to their low cost and high-power conversion efficiency (PCE). The perovskite material in the photovoltaic devices plays the fundamental role for the unique performances of PSC. Formamidinium based perovskite materials have become a hot-topic for research due to their excellent characteristics, such as a lower band gap (1.48 V), broader light absorption, and better thermal stability compared to methylammonium based perovskite materials. There are four phases of perovskite materials, named the cubic α-phase, tetragonal β-phase, orthorhombic γ-phase, and δ-phase (yellow). Many research focus on the transition of α-phase and δ-phase. α-Phase FA-based perovskite is very useful for photovoltaic application. However, the phase stability of α-phase FA-based perovskite materials is quite poor. It transforms into its useless δ-phase at room temperature. This instability will lead the degradation of PCE and the other optoelectronic properties. For the practical application of PSC, it is urgent to understand more about the mechanism of this transformation and boost the stability of α-Phase FA-based perovskite materials. This review describes the strategies developed in the past several years, such as mixed cations, anion exchange, dimensions controlling, and surface engineering. These discussions present a perspective on the stability of α-phase of FA-based perovskite materials and the coming challenges in this field

Hydrogen Bonds in Precursor Solution: The Origin of the Anomalous J–V Curves in Perovskite Solar Cells

Perovskite Solar Cells are a promising solar energy harvesting technology due to their low cost and high-power conversion efficiency. A high-quality perovskite layer is fundamental for a highly efficient perovskite Solar Cell. Utilizing a gas quenching process (GQP) can eliminate the need for toxic, flammable, and expensive anti-solvents in the preparation of perovskite layers. It is a promising candidate technology for large scale preparation of perovskite layers, as it can be easily integrated in a production line by coupling up-scalable techniques. The GQP removes the need for polar solvents in the precursor solution layer by using nitrogen flow, rather than extracting them with non-polar solvents. The crystallization dynamics in this process can be significantly different. In this study, we found that the quality of perovskite crystal from GQP is much more sensitive to Lewis base molecules (LBMs) in the precursor solution than it is in anti-solvents technology. Thus, the processing parameters of the LBMs in anti-solvents technology cannot be directly transferred to the GQP. An XRD and 1H NMR study explains the origin of the S-shaped J–V curves and how these LBMs hinder the reaction between PbI2 and monovelent cations