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Influenza A (H1N1) viruses are prone to antigenic mutations and are more variable than other influenza viruses. Therefore, they have caused continuous harm to human public health since the pandemic in 2009 and in recent times. Influenza A (H1N1) can be prevented and treated in various ways, such as direct inhibition of the virus and regulation of human immunity. Among antiviral drugs, the use of natural products in treating influenza has a long history, and natural medicine has been widely considered the focus of development programs for new, safe anti-influenza drugs. In this paper, we focus on influenza A (H1N1) and summarize the natural product-derived phytochemicals for influenza A virus (H1N1) prevention and treatment, including marine natural products, flavonoids, alkaloids, terpenoids and their derivatives, phenols and their derivatives, polysaccharides, and derivatives of natural products for prevention and treatment of influenza A (H1N1) virus. We further discuss the toxicity and antiviral mechanism against influenza A (H1N1) as well as the druggability of natural products. We hope that this review will facilitate the study of the role of natural products against influenza A (H1N1) activity and provide a promising alternative for further anti-influenza A drug development. [ABSTRACT FROM AUTHOR]

Underwater acoustic metasurfaces have broad application prospects for the stealth of underwater objects. However, problems such as a narrow operating frequency band, poor operating performance, and considerable thickness at low frequencies remain. In this study a reverse design method for ultra-thin underwater acoustic metasurfaces for low-frequency broadband is proposed using a tandem fully connected deep neural network. The tandem neural network consists of a pre-trained forward neural network and a reverse neural network, based on which a set of elements with flat phase variation and an almost equal phase shift interval in the range of 700–1150 Hz is designed. A diffuse underwater acoustic metasurface with 60 elements was designed, showing that the energy loss of the metasurface in the echo direction was greater than 10 dB. Our work opens a novel pathway for realising low-frequency wideband underwater acoustic devices, which will enable various applications in the future. [ABSTRACT FROM AUTHOR]

Defect engineering plays an important role in property modification for piezoelectric materials. In this work, we pay much attention to the effect of Nb nonstoichiometry on structure and properties of typical 0.95(K0.45Na0.55)Nb1+xO3–0.05Bi0.5Na0.5HfO3 ceramics. Large piezoelectric constant (d33 ~ 425 pC/N and d33∗ ~482 pm/V) together with high Curie temperature (TC ~ 315°C) have been achieved in the ceramics with excess Nb content (x = 0.01). However, the ceramics with deficient Nb element have seriously suppressed cryogenic εr‐T curves and deteriorated electrical properties. Multi‐scale characterizations including phase structure, microstructure, defect structure and domain structure have been adopted to explain the corresponding phenomenon. Defect complex VNb″″′-VO·· caused by deficient Nb induces clamped domain wall motion, leading to blocked polarization vector and poor electrical properties. On the contrary, the enhanced properties for the ceramics with excess Nb are attributed to easier domain switching due to the suppressed vacancies. We believe that defect engineering, for example nonstoichiometry, cannot only modulate electrical properties but also help us to understand some fundamental and critical problems about KNN‐based ceramics. [ABSTRACT FROM AUTHOR]

Extranodal natural killer/T‐cell lymphoma (ENKL), nasal‐type is a rare but highly aggressive disease with poor prognosis. Optimal treatment strategies for newly diagnosed localized ENKL have not been fully defined. Here we retrospectively analyzed 72 patients with newly diagnosed stage IE/IIE ENKL treated with gemcitabine, dexamethasone, and cisplatin (GDP) regimen chemotherapy with sandwiched radiotherapy in our department between May 2012 and September 2014. After 2 cycles of GDP induction chemotherapy, the complete response rate (CRR) and overall response rate (ORR) were 30.6% (22/72) and 91.7% (66/72). After whole treatment completion, the CRR and ORR were 81.9% (59/72) and 91.7% (66/72), respectively. With a median follow‐up of 57.8 months (Interquartile Range 54.0‐64.5 months), the 5‐year progression‐free survival rate was 70.9% (95% CI, 60.1% to 81.7%), and the 5‐year overall survival rate was 72.0% (95% CI, 61.6% to 82.4%), respectively. Patients with CRR after treatment had better prognosis than their counterparts. The major adverse events were myelosuppression, liver dysfunction, gemcitabine‐related skin rash, and digestive tract toxicities. Grade 3 to 4 neutropenia and thrombocytopenia were 18.0% (13/72) and 15.3% (11/72), respectively. No treatment related deaths were observed. It is concluded that the GDP regimen with sandwiched radiotherapy was an effective and well‐tolerated treatment for newly diagnosed stage IE/IIE ENKL, nasal‐type. [ABSTRACT FROM AUTHOR]

The strategy of modulating polarization rotation of potassium sodium-niobate ((K 0.5 Na 0.5)NbO 3 , KNN) lead-free piezoelectric materials was reported to boost piezoelectric properties and resultant piezocatalytic activities. The effectiveness of modulating polarization rotation was proved by degrading Rhodamine B (RhB) using three KNN-based samples with different phase structures (i.e., orthorhombic (O) phase, orthorhombic-tetragonal (O-T) coexistence phase, and rhombohedral-orthorhombic-tetragonal (R-O-T) coexistence phase). Poled samples with the R-O-T coexistence phase show a reaction rate constant of 0.091 min−1 owing to the easiest polarization rotation, 2.12 times more than that of poled O-phase featured samples with the most difficult polarization rotation. Enhanced piezocatalytic activities primarily originate from the easier polarization rotation and improved carrier concentration, accompanied by the trace of the mechano-charge generation. Therefore, modulating polarization rotation effectively boosts piezocatalysis of KNN-based materials, promising for harnessing natural energy and disease treatment. [Display omitted] • lead-free (K, Na)NbO 3 materials are eco-friendly piezocatalyst. • Proposing a new strategy to enhance there piezocatalysis. • Obtaining a high k value of 0.091 min−1, much superior to those of other materials. • Unveiling the physical mechanisms of the superior piezocatalytic activities. [ABSTRACT FROM AUTHOR]

Although the composition-driven multi-phase coexistence strategy has been widely used to modify the piezoelectric properties of potassium sodium niobate ((K, Na)NbO 3 , KNN) based ceramics, the trade-off between long-range ferroelectric ordering and chemical additives-induced disorder hinders the further improvement of piezoelectricity and makes the electric field-induced strain temperature-dependent. Herein, to resolve two issues, we proposed a new concept, that is, manipulating defect dipoles and local stress of a pre-constructed multi-phase coexistence through controlling zirconium (Zr) content. We validated the new concept by designing 0.96(K 0.4 Na 0.6)Nb 0.955 Sb 0.045 O 3 -0.04(Bi 0.5 Na 0.5)Zr (1+ x) O 3 ceramics. In samples with Zr deficiency (i.e., x =-0.1), we obtained high retention of 91% in normalized unipolar strain (S uni) over the temperature range of 30-160 °C, even under low electric fields of 10-20 kV/cm, superior to those of other representative KNN-based ceramics. In samples with slight Zr excess (i.e., x =0.07), we achieved an increase in direct piezoelectric coefficient (d 33) and converse piezoelectric coefficient (d 33 *) by 12% and 25%, respectively, in comparison with that at x =0. The enhanced temperature stability stems from the released domain walls that are pinned by defect dipoles, and the increased d 33 (and d 33 *) originates from the synergetic contributions of the multi-phase coexistence, increased grain size, and stabilization of the ZrO 2 secondary phase. Therefore, our new concept would benefit the composition design and performance improvement of KNN-based ceramics in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

Different types of defect dipoles form, F e A.. − V A ′ for A-site and F e N b ″ − V O.. for B-site according to the dopant sites [Fig. 1(a)]. Both of the temperature stable miniatured domain [Fig. 1(b)] and active defect dipole F e N b ″ − V O.. [Fig. 1(c)] in the B-site 0.05 leads to the preferable temperature stability, that is, the remnant polarization (P r) and unipolar strain (S) vary less than 10% and 15% in the temperature range of 20-140 °C, which is superior to other systems [Fig. 1(d)]. We believe that the strategy of designed defect dipoles is helpful for improving electrical properties and further promoting the development of KNN-based ceramics. [Display omitted] The designed defect-engineering has been proved to be an effective way to promote properties in potassium sodium niobate (KNN)-based ceramics. Here, we focus on the introduction of Fe element into different sites of KNN-based ceramics to form defects and optimize properties. Two types of defect dipoles can be formed, F e A.. − V A ′ for A-site and F e N b ″ − V O.. for B-site. Compared with the defect dipoles of A-site, the defect dipoles of B-site are sensitive to both electric field and temperature. So that, the B-site defect dipoles switch easily under the thermo-electric treatment, and share the same behavior with spontaneous polarization after removing the electric field, which compensates the remnant polarization. In addition, the domain miniaturizes as the Fe ions doping. Both of the defect dipole behavior and nanodomain lead to the preferable temperature stability: remnant polarization (P r) and unipolar strain (S) of the B-site engineered ceramics vary less than 10% and 15% in the temperature range of 20-140 °C. We hope that the strategy of designed defect dipoles is helpful for improving electrical properties and further promoting the development of KNN-based ceramics. [ABSTRACT FROM AUTHOR]

An investigation into photocatalysts mainly focuses on inorganic powders, and their fixation, recycle, and repair in an open and flowing environment remains a problem. Herein, the photocatalytic property of polyvinylidene fluoride (PVDF) is utilized to solve this problem. It can be facilely recycled and repaired because of the form of membrane, and porous structure ensures its sufficient contact with pollutants. In addition, its photocatalytic activity can be effectively modified by compositing TiO2 nanopowder, which performs better photocatalytic activity than equivalent content TiO2 powder, originated from the enhanced separation efficiency of electron and hole resulting from the extra driving force maybe generated by PVDF's ferroelectric spontaneous polarization and heterojunction structure, which reduces the recombination of charge carriers. In addition, the pore structure with large density and small size provides more reaction area for the composite structure, which also benefits for the enhancement of photocatalytic activities. Tight combination between PVDF and TiO2 guarantees the stable activity of the composites under flowing environment, and so PVDF/TiO2 composite can sustain its initial photocatalytic activity after at least 10 times cycles. More importantly, when the membrane is damaged, it can be easily repaired by the cost of a small quantity of solvent and can maintain its initial photocatalytic activity. This work would promote the understanding of physical mechanisms of enhanced photocatalytic activities, and recycle and repair properties in PVDF‐xTiO2 composites. [ABSTRACT FROM AUTHOR]

Background: There is a scarcity of data about the prognostic value of orbital invasion in esthesioneuroblastoma (ENB), as well as about its management strategies. Indications for the preservation of orbital contents remain controversial, and the evaluation of orbital invasion has been ill defined.Methods: This retrospective analysis contained 60 ENB patients with orbital invasion who underwent radiotherapy with or without surgery over the past 14 years. Orbital invasion was classified into three grades.Results: There were 52 patients at stage C and 8 at stage D, according to Foote classifications. Grade I, grade II and grade III orbital invasion was detected in 12, 23, and 25 patients, respectively. The median follow-up was 57 months (IQR 32-95 months). Fourteen patients received radical radiotherapy, with a 5-year overall survival (OS) of 63.5%; 46 received surgery plus radiation, with a 5-year OS of 70.7%; and the difference was not statistically significant (p = 0.847). Orbital preservation was feasible in 100% of cases, including 18 cases that extended to extraocular muscles or the eye globe. Five-year locoregional relapse-free survival was 100% in patients with prophylactic elective neck irradiation (PENI) and 58.1% in patients without PENI (p = 0.004). Univariate analysis showed that grade II/III orbital invasion was associated with poorer OS and progression-free survival. Neck metastasis (with a Foote stage of D) was independently associated with shorter OS and distant metastasis-free survival in multivariate analysis.Conclusions: Our data suggested that primary radiotherapy achieved comparable survival to surgery plus radiotherapy in advanced ENB. Invasion of either the extraocular muscles or the eye globe is not a contraindication for eye-sparing surgery. Orbital invasion in grade II/III was significantly associated with adverse survival outcomes. Prophylactic radiotherapy to the neck with N0 significantly reduces the risk of regional recurrence. [ABSTRACT FROM AUTHOR]

This paper proposes a metal artifact reduction method of using MV-CBCT images to correct metal artifacts in kV-CT images, especially for the complex metal artifacts caused by multi-metal interaction of patients with head and neck tumors. The different tissue regions are segmented in the MV-CBCT images to obtain template images and the metal region is segmented in the kV-CT images. Forward projection is performed to get sinogram of the template images, kV-CT images and metal region images. Artifact images can be reconstructed through those sonograms. Corrected images is generated by subtracting the artifact images from the original kV-CT images. After the first correction, the template images are generated again and brought into the previous step for iteration to get better correction result. CT data set of 7 patients are used in this study, compared with linear interpolation metal artifact (LIMAR) and normalized metal artifact reduction method, mean relative error of CT value is reduced by 50.5% and 63.3%, noise is reduced by 56.2% and 58.9%. The Identifiability Score of the tooth, upper/lower jaw, tongue, lips, masseter muscle and cavity in the corrected images by the proposed method have significantly improved (P < 0.05) than original images. The artifacts correction method proposed in this paper can effectively remove the metal artifacts in the images and greatly improve the CT value accuracy, especially in the case of multi-metal and complex metal implantation. [ABSTRACT FROM AUTHOR]