Low-cost X-ray detectors with high performance, durability, and flexibility, are required for a wide range of applications in several fields, such as medical (diagnostic radiology, imaging, etc.), nondestructive testing (radioscopic inspections, radiography testing, etc.), security and defence (baggage/body scanning systems, paper mail, etc.), nuclear and radiation industries (nuclear power plants, research reactors, users of nuclear gauges, etc.), and research and development. [1] X-ray detection using semiconductors, based on the direct generation of electrical signals by X-rays (i.e., direct scheme), offers better spatial resolution and a simpler route than indirect schemes, in which X-rays are converted into photons by scintillating phosphors before detection by photodiode arrays. [2] Currently, the conventional materials used for direct conversion of X-rays include stabilized amorphous Se (α-Se), PbI 2 , HgI 2 , CdTe, and CdZnTe. [3] Metal halide perovskites represent a family of the most promising materials for fascinating photovoltaic and photodetector applications due to their unique optoelectronic properties and much needed simple and low-cost fabrication process. The high atomic number (Z) of their constituents and significantly higher carrier mobility also make perovskite semiconductors suitable for the detection of ionizing radiation. By taking advantage of that, the direct detection of soft-X-ray-induced photocurrent is demonstrated in both rigid and flexible detectors based on all-inorganic halide perovskite quantum dots (QDs) synthesized via a solution process. Utilizing a synchrotron soft-X-ray beamline, high sensitivities of up to 1450 µC Gy air −1 cm −2 are achieved under an X-ray dose rate of 0.0172 mGy air s −1 with only 0.1 V bias voltage, which is about 70-fold more sensitive than conventional α-Se devices. Furthermore, the perovskite film is printed homogeneously on various substrates by the inexpensive inkjet printing method to demonstrate large-scale fabrication of arrays of multichannel detectors. These results suggest that the perovskite QDs are ideal candidates for the detection of soft X-rays and for large-area flat or flexible panels with tremendous application potential in multidimensional and different architectures imaging technologies.

For superficial skin tumors (SST) with high incidence, surgery and systemic therapy are relatively invasive and possible to cause severe side effect, respectively. Yet, topical therapy is confronted with the limited transdermal capacity because of the stratum corneum barrier layer of skin. Therefore, it is crucial to develop a highly effective and minimally invasive alternative transdermal approach for treating SST. Here, we developed gold nanocage (AuNC)- and chemotherapeutic drug doxorubicin (DOX)-loaded hyaluronic acid dissolving microneedle (MN) arrays. The loaded AuNCs are not only reinforcers to enhance the mechanical strength of the MNs, but also effective agents for photothermal therapy to obtain effective transdermal therapy for SST. The resultant MNs can effectively penetrate the skin, dissolve in the skin and release cargoes within the tumor site. Photothermal effect of AuNCs initiated by near-infrared laser irradiation combined with the chemotherapy effect of DOX destroyed tumors synergistically. Moreover, we verified the potent antitumor effects of the DOX/AuNC-loaded MNs after four administrations to SST-bearing mice without obvious side effects. Therefore, the drug/AuNC-loaded dissolving MN system provides a promising platform for effective, safe, minimally invasive combined treatment of SST.

No abstract

The composition of the intestinal microbiome varies considerably between individuals and is correlated with health 1 . Understanding the extent to which, and how, host genetics contributes to this variation is essential yet has proved to be difficult, as few associations have been replicated, particularly in humans 2 . Here we study the effect of host genotype on the composition of the intestinal microbiota in a large mosaic pig population. We show that, under conditions of exacerbated genetic diversity and environmental uniformity, microbiota composition and the abundance of specific taxa are heritable. We map a quantitative trait locus affecting the abundance of Erysipelotrichaceae species and show that it is caused by a 2.3 kb deletion in the gene encoding N -acetyl-galactosaminyl-transferase that underpins the ABO blood group in humans. We show that this deletion is a ≥3.5-million-year-old trans-species polymorphism under balancing selection. We demonstrate that it decreases the concentrations of N -acetyl-galactosamine in the gut, and thereby reduces the abundance of Erysipelotrichaceae that can import and catabolize N -acetyl-galactosamine. Our results provide very strong evidence for an effect of the host genotype on the abundance of specific bacteria in the intestine combined with insights into the molecular mechanisms that underpin this association. Our data pave the way towards identifying the same effect in rural human populations.

No abstract

Psoriasis is a common autoimmune and chronic inflammatory skin disorder globally affecting 0.51–11.43% of adults. Inflammation-associated cell death in keratinocytes plays a key role in the process of integrate inflammatory cascade in psoriasis. Necroptosis is a regulated necrotic cell death mediated by receptor interacting protein kinase 1 (RIPK1), RIPK3, and mixed lineage kinase domain-like pseudokinase (MLKL), which participates in many human inflammatory diseases. However, the mechanism and function of programmed necrosis in psoriasis is not well-illustrated. In the current study, we provide evidence for the involvement of necroptosis in psoriasis. RIPK1 and MLKL were significantly upregulated and localized in all layers of the epidermis in human psoriatic lesions, while RIPK3 and phosphorylated MLKL were mainly expressed in keratinocytes, which located in the upper layers. Increased tendency of necroptosis was also found in IMQ-induced psoriasiform skin of mice. Further, we discovered that both the inhibitor of RIPK1 R-7-Cl-O-Necrostatin-1 (Nec-1s) and MLKL-inhibitor necrosulfonamide (NSA) suppressed necroptosis in HaCaT cells and IMQ mouse models, powerfully blocked IMQ-induced inflammatory responses in vivo, and significantly downregulated the production of inflammatory factors like IL-1β, IL-6, IL-17A, IL-23a, CXCL1, and CCL20. These findings promote the development of new therapies for the treatment of necroptosis-activated pathologies for psoriasis.

Metamaterials attain their behavior due to resonant interactions among their subwavelength components and thus show specific designer features only in a very narrow frequency band. There is no simple way to dynamically increase the operating bandwidth of a narrowband metamaterial, but it may be possible to change its central frequency, shifting the spectral response to a new frequency range. In this paper, we propose and experimentally demonstrate a metamaterial absorber that can shift its central operating frequency by using mechanical means. The shift is achieved by varying the gap between the metamaterial and an auxiliary dielectric slab parallel to its surface. We also show that it is possible to create multiple absorption peaks by adjusting the size and/or shape of the dielectric slab, and to shift them by moving the slab relative to the metamaterial. Specifically, using numerical simulations we design a microwave metamaterial absorber and experimentally demonstrate that its central frequency can be set anywhere in a 1.6 GHz frequency range. The proposed configuration is simple and easy to make, and may be readily extended to THz frequencies.

No abstract