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Hybrid 2D layered perovskites are solution-processed quantum wells whose optoelectronic properties are tunable by varying the thickness of the inorganic slab. Here Blancon et al. work out a general behavior for dependence of the excitonic properties in layered 2D perovskites.

An approach for nanoscale 3-D tomography of organic carbon (OC) and associated mineral nanoparticles was developed to illustrate their spatial distribution and boundary interplay, using synchrotron-based transmission X-ray microscopy (TXM). The proposed 3-D tomography technique was first applied to in situ observation of a laboratory-made consortium of black carbon (BC) and nanomineral (TiO2, 15 nm), and its performance was evaluated using dual-scan (absorption contrast and phase contrast) modes. This novel tool was then successfully applied to a natural OC–mineral consortium from mountain soil at a spatial resolution of 60 nm, showing the fine structure and boundary of OC, the distribution of abundant nano-sized minerals, and the 3-D organo-mineral association in situ. The stabilization of 3500-year-old natural OC was mainly attributed to the physical protection of nano-sized iron (Fe)-containing minerals (Fe oxyhydroxides including ferrihydrite, goethite, and lepidocrocite), and the strong organo-mineral complexation. In situ evidence revealed an abundance of mineral nanoparticles, in dense thin layers or nano-aggregates/clusters, instead of crystalline clay-sized minerals on or near OC surfaces. The key working minerals for C stabilization were reactive short-range-order (SRO) mineral nanoparticles and poorly crystalline submicron-sized clay minerals. Spectroscopic analyses demonstrated that the studied OC was not merely in crisscross co-localization with reactive SRO minerals; there could be a significant degree of binding between OC and the minerals. The ubiquity and abundance of mineral nanoparticles on the OC surface, and their heterogeneity in the natural environment may have been severely underestimated by traditional research approaches. Our in situ description of organo-mineral interplay at the nanoscale provides direct evidence to substantiate the importance of mineral physical protection for the long-term stabilization of OC. This high-resolution 3-D tomography approach is a promising tool for generating new insight into the interior 3-D structure of micro-aggregates, the in situ interplay between OC and minerals, and the fate of mineral nanoparticles (including heavy metals) in natural environments.

Relativistic electron beams driven by laser wakefield acceleration were utilized to produce ultrashort neutron sources. The experiment was carried out on the 38 fs, ∼0.5 J, 800 nm Ti:Sapphire laser in the 10 TW UT3 laser lab at University of Texas at Austin. The target gas was a high density pulsed gas jet composed of 90% He and 10% N2. The laser pulse with a peak intensity of 1.5 × 1018 W/cm2 interacted with the target to create a cylindrical plasma channel of 60 μm radius (FWHM) and 1.5 mm length (FWHM). Electron beams of ∼80 pC with the Gaussian energy distribution centered at 37 MeV and a width of 30 MeV (FWHM) were produced via laser wakefield acceleration. Neutron fluences of ∼2.4 × 106 per shot with hundreds of ps temporal length were generated through bremsstrahlung and subsequent photoneutron reactions in a 26.6 mm thick tungsten converter. Results were compared with those of simulations using EPOCH and GEANT4, showing agreement in electron spectrum, neutron fluence, neutron angular distribution and conversion rate.

In this paper, we describe the evolution of Toxic Chemical Substances Control Act (TCSCA) regulated by Taiwan Environmental Protection Administration during the past two decades. The TCSCA was originally drafted for the management of utilization and operation of toxic chemical substances from cradle to grave. Following the 921 earthquake in central Taiwan in 1999, the newly issued Disaster Prevention and Mitigation Act further required that the risk management and disaster mitigation from all listed toxic chemicals must also be regulated in TCSCA. Since then, significant modification in the Act and new regulations are added and implemented. In addition, Taiwan EPA is also established information and monitoring centres and seven emergency response teams. These facilities provide 24-hour service and have at least 25 people on duty at all times. The main tools used by these facilities are environmental monitoring equipment, personal protection equipment, and response equipment for leak patching and chemical transfer. The increased regulatory control and response capabilities have greatly reduce the occurrence and potential impact from toxic chemicals incidents as evident from the incident statistics.

Introduction: Myelodysplastic syndrome (MDS) is a heterogeneous constellation of myeloid neoplasms originating from the clonal proliferation of aberrant hematopoietic stem cells (HSC). The human kinome, which comprises over five hundred kinases, plays a critical role in regulating numerous cellular functions. Although the dysregulation of kinases has been observed in various human cancers, the characterization and clinical implications of kinase expressions in MDS have not been investigated before. Methods: Overall, 341 patients diagnosed with primary MDS according to the 2016 WHO classification, who had adequate cryopreserved diagnostic unsorted bone marrow (BM) samples for DNA and RNA sequencing, were recruited. The normalized gene expressions of a total of 517 kinase gene were studied. We first identified those kinases whose expressions were higher in MDS patients than in healthy controls, and then used LASSO-regularized Cox proportional hazards regression to identify prognostically significant kinases to construct the KInase Stratification Score (KISS). Results: We discovered that the expression levels of seven kinases (PTK7, KIT, MAST4, NTRK1, PAK6, CAMK1D, PRKCZ) could predict patient outcome, and we used these kinases to construct the KISS; we further validated its prognostic significance in two external MDS cohorts. A higher KISS was associated with older age, higher BM blast percentage, higher IPSS-R risk, complex karyotype, and mutations in several adverse-risk genes in MDS. In the multivariate analysis, a higher KISS was proved to be an independent unfavorable risk factor. Conclusions: Altogether, our findings suggest that KISS holds the potential to improve the current prognostic scheme of MDS, and inform novel therapeutic opportunities.

Retinal vasoproliferative tumors (RVPTs) are rare benign retinal lesions typically located in the inferotemporal peripheral retina. Several treatment options exist for the management of RVPTs, but no consensus has been proposed. There are only a few reports on the use of anti-vascular endothelial growth factor with bevacizumab to treat exudative or neovascular retinal changes secondary to RVPTs. This report describes a 68-year-old female with a history of systemic hypertension that presented with a 2-week history of gradual loss of visual acuity in the right eye. Fundoscopic examination showed a RVPTs with atypical location that had a favorable response to two-intravitreal aflibercept injections 1 month apart, with resulting subretinal fluid absorption and tumor regression.

Here, we report a case of bilateral cystoid macular edema (CME) in a woman with phakic eyes after 22 years of latanoprost use. Optical coherence tomography revealed multiple intraretinal cysts, and fluorescein angiography revealed characteristic petaloid dye leakage from the perifoveal capillaries. A cause-effect relationship was suspected when CME resolved after switching from latanoprost to dorzolamide, as confirmed by positive rechallenge and dechallenge tests. Since prostaglandin analog-induced CME has only been reported in patients with pseudophakic, aphakic, or phakic eyes with retinal conditions predisposing to macular edema, this seems to be the first reported case of latanoprost-induced CME in a patient with phakic eyes without retinal risk factors.

Indirect ophthalmoscopy and handheld retinal imaging are the most common and traditional modalities for the evaluation and documentation of the pediatric fundus, especially for pre-verbal children. Optical coherence tomography (OCT) allows for in vivo visualization that resembles histology, and optical coherence tomography angiography (OCTA) allows for non-invasive depth-resolved imaging of the retinal vasculature. Both OCT and OCTA were extensively used and studied in adults, but not in children. The advent of prototype handheld OCT and OCTA have allowed for detailed imaging in younger infants and even neonates in the neonatal care intensive unit with retinopathy of prematurity (ROP). In this review, we discuss the use of OCTA and OCTA in various pediatric retinal diseases, including ROP, familial exudative vitreoretinopathy (FEVR), Coats disease and other less common diseases. For example, handheld portable OCT was shown to detect subclinical macular edema and incomplete foveal development in ROP, as well as subretinal exudation and fibrosis in Coats disease. Some challenges in the pediatric age group include the lack of a normative database and the difficulty in image registration for longitudinal comparison. We believe that technological improvements in the use of OCT and OCTA will improve our understanding and care of pediatric retina patients in the future.

Background Obstructive sleep apnoea (OSA) is a common chronic condition that is associated with significant morbidity and economic cost. Prolonged wait times are increasingly being recognised as a barrier to diagnosis and treatment of many chronic diseases; however, no study to date has prospectively evaluated the impact of wait times on health outcomes in OSA. Objective The purpose of this study is to determine whether treatment outcomes for individuals with OSA differ between patients managed using an expedited versus standard pathway. Methods A pragmatic randomised controlled trial design will be used with a target sample size of 200 adults. Participants with clinically significant uncomplicated OSA will be recruited through referrals to a large tertiary care sleep centre (Calgary, AB, Canada) and randomised to either early management (within 1 month) or usual care (∼6 months) with a 1:1 allocation using a concealed computer-generated randomisation sequence. The primary outcome will be adherence to positive airway pressure (PAP) therapy at 3 months after treatment initiation. Secondary outcomes will include change in sleepiness, quality of life, patient satisfaction, and patient engagement with therapy from baseline to 3 months after PAP initiation, measured using validated questionnaires and qualitative methods. Anticipated results This study will determine whether expedited care for OSA leads to differences in PAP adherence and/or patient-reported outcomes. More broadly, the findings of this study may improve the understanding of how wait time reductions impact health outcomes for other chronic diseases.

Growth factors (GF) are critical cytokines in wound healing. However, the direct delivery of these biochemical cues into a wound site significantly increases the cost of wound dressings and can lead to a strong immunological response due to the introduction of a foreign source of GFs. To overcome this challenge, we designed a poly(ethylene glycol) diacrylate (PEGDA) hydrogel with the potential capacity to sequester autologous GFs directly from the wound site. We demonstrated that synthetic peptide sequences covalently tethered to PEGDA hydrogels physically retained human transforming growth factor beta 1 (hTGFβ1) and human vascular endothelial growth factor (hVEGF) at 3.2 and 0.6 ng/mm2, respectively. In addition, we demonstrated that retained hTGFβ1 and hVEGF enhanced human dermal fibroblasts (HDFa) average cell surface area and proliferation, respectively, and that exposure to both GFs resulted in up to 1.9-fold higher fraction of area covered relative to the control. After five days in culture, relative to the control surface, non-covalently bound hTGFβ1 significantly increased the expression of collagen type I and hTGFβ1 and downregulated vimentin and matrix metalloproteinase 1 expression. Cumulatively, the response of HDFa to hTGFβ1 aligns well with the expected response of fibroblasts during the early stages of wound healing.

This paper demonstrates a predictive method for the spatially explicit and periodic in situ monitoring of surface water quality in a small lake using an unmanned aerial vehicle (UAV), equipped with a multi-spectrometer. According to the reflectance of different substances in different spectral bands, multiple regression analyses are used to determine the models that comprise the most relevant band combinations from the multispectral images for the eutrophication assessment of lake water. The relevant eutrophication parameters, such as chlorophyll a, total phosphorus, transparency and dissolved oxygen, are, thus, evaluated and expressed by these regression models. Our experiments find that the predicted eutrophication parameters from the corresponding regression models may generally exhibit good linear results with the coefficients of determination (R2) ranging from 0.7339 to 0.9406. In addition, the result of Carlson trophic state index (CTSI), determined by the on-site water quality sampling data, is found to be rather consistent with the predicted results using the regression model data proposed in this research. The maximal error in CTSI accuracy is as low as 1.4% and the root mean square error (RMSE) is only 0.6624, which reveals the great potential of low-altitude drones equipped with multispectrometers in real-time monitoring and evaluation of the trophic status of a surface water body in an ecosystem.

A new tandem mass spectrometer is constructed and applied to kinetic and spectroscopic investigation of charged water clusters. The results of the thermochemical measurements for H(super +1)(H2O)(sub 4-10) and OH(super -1)(H2O)(sub 3-7) at well-defined cluster temperatures are presented.

The results of crosstalk investigations and microlens (mu-lens) scan experiments in a color CMOS image sensor with active pixel structure are described. The spectral characteristics measured at different relative apertures (f-number) are discussed.

Spectroscopic ellipsometry and Raman scattering measurements of single-crystal Li _x CoO _2 ( x = 0.33, 0.43, 0.50, 0.53, 0.72, and 0.87) are reported. The room temperature optical absorption spectra for x values in the range of 0.33–0.72 exhibit three bands near 1.60, 3.35, and 5.20 eV. On the basis of first-principles calculations, the observed optical excitations were appropriately assigned. The charge-transfer absorption bands shift to higher energies in Li _0.87 CoO _2 because of symmetry-breaking-induced distortions of the hybridized Co-O orbitals with shifted oxygen 2 p states. Furthermore, two Raman-active phonon modes, which display E _g and A _1 _g symmetry, are sensitive to lithium doping. Upon cooling across 200 K, which is the antiferromagnetic phase transition temperature of Li _0.50 CoO _2 , large splitting of the E _g mode and a discontinuous change in the frequency of the A _1 _g mode were observed. These results highlight the importance of spin-phonon coupling in Li _0.50 CoO _2 .

The monomeric nature of the inactive Stat-91, a 91 kd protein that functions as a signal transducer and activator of transcription, in the cytoplasm of untreated cells is confirmed. A stable homodimer results from interferon gamma-induced phosphorylation. SH2-phosphotyrosyl peptide interactions mediate dimerization of Stat-91.

An integrated piecewise thermal equilibrium approach based on the first-principles calculation method was developed to calculate bias dependent electronic structures and current- and differential conductance-voltage characteristics of the gold-benzene-1,4-dithiol-gold molecular junction. The results obtained provide insight into the bias induced electron transfer between the two electrodes which causes the local electronic structures in the two electrodes to be different.

Dysregulation of cell surface proteolysis has been strongly implicated in tumorigenicity and metastasis. In this study, we delineated the role of hepatocyte growth factor activator inhibitor-2 (HAI-2) in prostate cancer (PCa) cell migration, invasion, tumorigenicity and metastasis using a human PCa progression model (103E, N1, and N2 cells) and xenograft models. N1 and N2 cells were established through serial intraprostatic propagation of 103E human PCa cells and isolation of the metastatic cells from nearby lymph nodes. The invasion capability of these cells was revealed to gradually increase throughout the serial isolations (103E