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Due to the easy formation of compact molecular packing arrangements and the favorable photophysical and electrochemical properties, donor-acceptor-donor (D-A-D)-type small molecule hole-transporting materials (HTMs) have been widely synthesized and researched to improve the efficiency and stability of perovskite solar cells (PSCs). The main approach in recent experiments has been to seek good acceptors, whereas the influence of the electron-donating units has been less reported. In this work, six new benzothiadiazole-based D-A-D-type HTMs are tailored by employing the ethyl-substituted phenoxazine (POZ), phenothiazine (PTZ) and carbazole (CZ) as the donors. To obtain an elementary understanding of new HTMs, the electronic, optical, hole-transporting and interfacial properties are simulated with quantum chemistry methods. The results indicate that all tailored HTMs exhibit suitable energy alignment compared with the band structures of the perovskite, and the continuous highest occupied molecular orbital (HOMO) levels will be helpful for interfacial energy regulation. In comparison with the YN1, the maximum absorption wavelengths of the newly designed HTMs are red-shifted due to the decreased excitation energies from the ground-state to the first singlet excited-state. Importantly, the hole mobilities of all designed HTMs are distinctly higher than the referenced YN1, which is contributed by the better planarity of the molecular skeleton and the easier orbital overlapping between adjacent molecules. The interfacial simulations manifest that the FAPbI3/SM37 system displays a more stable adsorption configuration and greater charge redistributions at the interface compared to YN1, which further promotes the separation of photogenerated electron-hole pairs. Moreover, larger Stokes shifts and better solubility are also acquired for the new HTMs. In summary, our calculations not only propose several potential highly efficient HTMs, but also provide useful insights at the atomic level for the experimental synthesis of new D-A-D-type HTMs.
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Among the factors that lead to the reduction of the efficiency of perovskite solar cells (PSCs) the difficulty involved in realizing a high-quality film and the efficient charge transfer that takes place at the interface between electron-transport layer (ETL) and perovskite is worth mentioning. Here, a strategy for planar-type devices by natural bio-functional interfaces that uses a buried electron-transport layer made of cobalamin complexed tin oxide (SnO2 @B12 ) is demonstrated. Having systematically investigated the effects of SnO2 @B12 interfacial layer in perovskite solar cells, it can be concluded that cobalamin can chemically link the SnO2 layer and the perovskite layer, resulting in improved perovskite film quality and interfacial defect passivation. Utilizing SnO2 @B12 improves the efficiency of planar-type PSCs by 20.60 %. Furthermore, after 250â h of exposure to an ambient atmosphere, unsealed PSCs containing SnO2 @B12 degrade by 10 %. This research provides a viable method for developing bio-functional molecules that will increase the effectiveness and durability of planar-perovskite solar cells.
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Microwave (MW) and enzyme catalysis are two emerging processing tools in the field of food industry. Recently, MW has been widely utilized as a novel type of green and safe heating energy. However, the effect of MW irradiation on enzyme activity is not described clearly. The intrinsic mechanisms behind enzyme activation and inactivation remain obscure. To apply better MW to the field of enzyme catalysis, it is essential to gain insights into the mechanism of MW action on enzyme activity. This review summarizes the changes in various enzyme activity during food processing, especially under MW irradiation. The intrinsic mechanism of thermal and nonthermal effects of MW irradiation was analyzed from the perspective of enzyme reaction kinetics and spatial structure. MW irradiation temperature is a vital parameter affecting the catalytic activity of enzymes. Activation of the enzyme activity is achieved even at high MW power when the enzyme is operating at its optimum temperature. However, when the temperature exceeds the optimum temperature, the enzyme activity is inhibited. In addition to MW dielectric heating effect, nonthermal MW effects also alter the microenvironment of reactive system. Taken together, enzyme activity is influenced by both thermal and nonthermal MW effects.
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Indústria de Processamento de Alimentos , Micro-Ondas , TemperaturaRESUMO
Perovskite oxides are widely used in electrochemical cells, profiting from their excellent accommodation of different elements and structure stability. Here, it is reported that when rapidly exceeding the electrochemical stability window of a perovskite oxide through electrochemical treatment, nanoparticles can dynamically exsolve from the perovskite lattice, yielding a nanoparticle decorated material (NDM) with fascinating particle population and distribution. It is reported that as compared to the NDM produced by chemical gas reduction, electrochemical treatment fabricated NDM shows much better electrochemical performance. At 900 °C, a peak power density (PPD) of 896 mW cm-2 (more than tenfold enhancement) is obtained for a yttrium stabilized zirconia (YSZ) electrolyte-supported symmetrical cell with La0.43 Ca0.37 Ti0.8 Co0.1 Fe0.1 O3- δ (LCTCF) electrode after electrochemical treatment for several minutes, while it only reaches to 210 mW cm-2 after chemical gas treatment for tens of hours using humidified hydrogen as fuel. The study establishes a new fairyland for tuning the performance of-but not limited to-the electrochemical cells.
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Most tumors have more severe hypoxia levels than normal tissue; tumor hypoxia is thus a useful target for cancer treatment. Here, we develop an effective oxygen delivery vehicle of polydopamine-nanoparticle-stabilized oxygen microcapsules by interfacial polymerization. The oxygen microcapsules have excellent biocompatibility. Oxygen could easily diffuse out from the microcapsules, thus increasing and maintaining the microenvironment at an oxygen-rich state. In vitro cell cultures confirm that oxygen microcapsules could effectively improve the hypoxia microenvironment, showing the lowest fluorescent intensity of hypoxia-green-labeled cells. When injected subcutaneously in vivo, oxygen microcapsules could also improve the tumor's hypoxia microenvironment, thus suppressing the growth of tumor. Synergetic therapy using oxygen microcapsules and gemcitabine drugs is an effective way for tumor treatment, showing the best performance in suppressing the tumor's growth.
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Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Indóis/química , Nanopartículas/química , Oxigênio/química , Polímeros/química , Cápsulas , Indóis/síntese química , Estrutura Molecular , Tamanho da Partícula , Polimerização , Polímeros/síntese químicaRESUMO
The design of new molecules with theoretical chemistry methods and further obtaining a fundamental understanding of the structure-property relationship are important for the development of high-efficiency hole-transporting materials (HTMs). Herein, the effect of semi-locked and fully-locked cores was systematically investigated based on two conformation-tunable tetrathienylethene (TTE) and tetraphenylethylene (TPE) units. Our results show that the highest occupied molecular orbital (HOMO) levels of the locked TTE-2 and TTE-3 are clearly down-shifted compared with that of the unlocked TTE-1, which is due to the decreased electronic conjugation between the locked cores and the triphenylamine (TPA) arms, whereas the same situation is not found for TPE-3 due to the twisted core configuration. Compared with the TTE-series, the TPE-series exhibits less optical absorption in the visible light region and enhanced stability. Meanwhile, the hole mobility of the designed HTMs displays an increased trend from the unlocked core to the semi-locked and fully-locked cores due to the gradually increasing hole transfer integral with enhanced molecular planarity. In addition, we also found that the reorganization energy of the locked TTE cores is obviously lowered compared to that of the unlocked one, which plays an important role in increasing the hole mobility. In summary, this work can provide some useful clues for designing high-efficiency two-dimensional HTMs, and two potential promising candidates (TTE-3 and TPE-3) are proposed.
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Poly(3,4-ethylenedioxythiophene) (PEDOT) has aroused great interest in organic electrics because of its high electrical conductivity and mechanical flexibility. To improve the charge transport, it can act as an ionic liquid (IL) additive due to its ion characteristics and high electrical conductivity. Herein, we investigated the hole-transport performance of PEDOT treated by ILs featuring specific ion ratios (4 : 1, 3 : 1, 2 : 1, 1 : 1, 1 : 2, 1 : 3, and 1 : 4) of the cation and anion through classical dynamics simulations and quantum mechanics computations. The hole mobility of the amorphous PEDOT, constituting nine EDOT monomers, could be improved to 16.81, 18.03, and 10.14 cm2 V-1 s-1 when synergistically regulating the ion ratio to 2 : 1, 3 : 1, and 4 : 1. Consequently, these ratios potentially achieved nearly a 100-fold improvement in the electrical conductivity with respect to the pristine system. The improvements mainly stemmed from the fact that decreasing the amount of anions in ILs and prolonging the chain length of PEDOT yielded an ordered face-to-face π-π stacking. The electronic coupling and charge excitation further confirmed that the anions play an active role in tunneling the hole transport in ILs/heterogeneous PEDOT, and the highest occupied molecular orbital (HOMO) energy level of PEDOT was up-shifted significantly after treatment by the ratios of 2 : 1, 3 : 1, and 4 : 1, which favored the electron-donating ability and was in line with the extraordinary enhancement of the hole mobility. Our results imply that regulating the ion ratio in ILs is a novel strategy for modulating the electronic properties and π-stacked morphology of PEDOT.
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Multiple absorbers that function in different absorption regions (near infra-red (NIR) and UV-Visible (UV-Vis)) have been widely used in solar cell applications to enhance the light-harvesting. Herein, two special co-sensitizing Models 1 and 2, which feature either saturated dye IQ21 or saturated co-sensitizer S2, have been added to a TiO2 surface to explore the effect of the altered sensitizing sequence, namely the co-sensitizing ratio of IQ21/S2 and S2/IQ21 on the electrostatic potential variation (ΔV), electron injection efficiency (ηinj'), and Förster resonance energy transfer (FRET), using density functional theory and first-principle molecular dynamics simulations. The ΔV related to the open-circuit voltage (Voc) is insensitive in both Models 1 and 2. However, the absorption (λabs) and ηinj' associated with the short-circuit density (Jsc) display a significant deviation (the λabs for 1 is red-shifted compared to that of 2, and the ηinj' for 1 is improved by 56%). Meanwhile, Model 1 manifests a suppressed FRET and potentially favors co-sensitizer S2 functioning as the electron-injector and not the energy-donor. Another two possible Models 3 and 4 that feature a reduced adsorption of IQ21 and S2 relative to 1 and 2 were considered further, and the result mirrors the main trend in 1 and 2, except for the ηinj'. Overall, it implies that sensitizing a larger absorber with NIR features to saturate it first, then introducing a smaller absorber with UV-Vis features, can potentially improve the electron injection and diminish electron-hole recombination considerably. Our results provide a comprehensive analysis of the active role of an optimized sensitizing sequence to improve the conversion efficiency.
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Molecular-surfactant-stabilized emulsions are susceptible to coalescence and Ostwald ripening. Amphiphilic particles, which have a much stronger anchoring strength at the interface, could effectively alleviate these problems to form stable Pickering emulsions. Herein, we describe a versatile method to fabricate biocompatible amphiphilic dimer particles through controlled coprecipitation and phase separation. The dimer particles consist of a hydrophobic PLA bulb and a hydrophilic shellac-PEG bulb, thus resembling nonionic molecular surfactants. The size and diameter ratio of the dimer particles are readily tunable, providing flexible control over the water/oil interfacial curvature and thus the type of emulsion. The particle-stabilized emulsions were stable for a long period of time and could be destabilized through a pH-triggered response. The biocompatible amphiphilic dimer particles with tunable morphology and functionality are thus ideal colloidal surfactants for various applications.
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Materiais Biocompatíveis/química , Tensoativos/química , Coloides , Dimerização , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Poliésteres/química , Polietilenoglicóis/químicaRESUMO
Thiophene/benzene-fused π-conjugated systems are normally employed as the core units of two- and three-dimensionally expanded small molecule hole-transporting materials (HTMs) to improve their electronic and charge transport properties, whereas comparison studies between two-dimensional and three-dimensional core conformations are less reported. To further find useful clues for the design of highly-efficient small molecule HTMs and to find new core units, in this work, four HTM molecules are designed by employing triphenylene, benzotrithiophene, triptycene, and thiophenetriptycene as the core units, and simulated with density functional theory combined with the Marcus hopping model. Our results show that all the considered HTMs display appropriate molecular energy levels, less optical absorption in the visible light region and large Stokes shifts, and high hole mobilities (9.80 × 10-2 cm2 V-1 s-1). Compared with the two-dimensional core structures, the three-dimensional cores exhibit evident superiorities with the same chemical components. Meanwhile, we also find that the quasi-degenerate HOMO energy levels will be helpful to enlarge the transfer integrals between adjacent molecules, and further to promote the hole transport in HTMs. By considering the various elements simultaneously, these investigated HTMs (S-1-S-4) with thiophene- and benzene-fused cores can be expected as potential promising candidates to help create more efficient solar cells.
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OBJECTIVE: To study the effects of rutin on myocardial enzyme in serum and myocardial morphology in diabetic mice induced by streptozotocin (STZ). METHODS: A model of type 1 diabetic mice was established in 48 male kunming mice with daily intraperitoneal injection of streptozotocin (STZ) 62.5 mg/kg for 5 consecutive days. 12 male Kunming mice were selected as normal group randomly. The established successfully diabetic mice were randomly divided into the model group, irbesartan group [45 mg/ (kg?d)], low-, high-dose rutin groups [50, 100 mg/ (kg?d)]. The mice in the normal and the model groups were given sodium carboxymethyl cellulose solution (CMC-Na, 1 g/L) by intragastric administration respectively. After administration for 8 weeks, the levels of creatine kinase (CK), creatine kinase isoenzymes (CK-MB), hydroxybutyrate dehydrogenase (HBDH), and lactate dehydrogenase (LDH) in serum were detected by blood biochemical analyzer. The cardiac myocardial morphology was observed by HE staining, Masson trichrome staining and electron microscope. RESULTS: Compare to the normal group, the levels of the myocardial enzyme in serum evidently increased in the model group (P<0.01); Compare to the model group, the levels of the myocardial enzyme in serum decreased in low-, high-dose rutin groups; The levels of HBDH and LDH declined remarkably in the high-dose rutin group relative to the low-dose group (P<0.05); Compared to the high-dose group, the level of LDH increased in the irbesartan group (P<0.05).Moreover, relative to the model group, the morphology of myocardial tissue, the degree of fibrosis and the ultrastructure of myocardial tissue in mice were significantly improved in low-, high-dose rutin groups, and the effects were more significant in the high-dose rutin group. CONCLUSION: Rutin could decrease the levels of myocardial enzyme in serum in diabetic mice, improve the cardiac cell morphology and alleviate myocardial injury.
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Diabetes Mellitus Experimental , Coração/efeitos dos fármacos , Miocárdio/enzimologia , Rutina/farmacologia , Animais , Creatina Quinase/sangue , Hidroxibutirato Desidrogenase/sangue , L-Lactato Desidrogenase/sangue , Masculino , Camundongos , Miocárdio/patologiaRESUMO
To design efficient dyes for dye-sensitized solar cells (DSSCs), using a Zn-coordinated phthalocyanine (TT7) as the prototype, a series of phthalocyanine dyes (Pcs) with different metal ions and peripheral/axial groups have been investigated by means of density functional theory (DFT) and time-dependent DFT (TDDFT) methods. Computational results show that the iodinated Al-based dye with a peripheral amino group (Al-I-NH2-Pc) exhibits the largest redshift in the maximum absorbance (λ(max)). In addition, Al-based dyes have appropriate energy-level arrangements of frontier orbitals to keep excellent balance between electron injection and regeneration of oxidized dyes. Further, it has been found that the intermolecular π-staking interaction in Al-I-Pc molecules is weaker than the other metal-based Pcs, which may effectively reduce dye aggregation on the semi-conductor surface. All these results suggest iodinated Al-based Pcs (Al-I-Pcs) to be potentially promising sensitizers in DSSCs.
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The structural and electronic properties of an organic dye C258 before and after being adsorbed onto a TiO2(101) surface by two adsorption modes, monodentate (Mha) and bidentate bridging (BBH), have been investigated in detail. The combination of density functional tight-binding (DFTB), density functional theory (DFT), and time-dependent DFT (TDDFT) approaches have been employed. DFT calculations show that C258 has remarkable charge-transfer characteristics, which favors fast electron injection from the excited dye to the conduction band of TiO2. A detailed analysis of the adsorbate contributions of the dye molecule to band states of TiO2 shows a strong coupling of the adsorbate orbitals with the substrate orbitals. Significant electronic transfer characteristics across the interface reveal a direct electron injection mechanism arising from the electronic excitation of the anchoring group of C258 to the conduction bands of TiO2. The adsorption energy and the electron density distribution demonstrate that the BBH structure is more stable and has a stronger coupling with TiO2 than the Mha pattern, which is able to better promote the electron injection to increase the efficiency of dye-sensitized solar cells (DSSCs).
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OBJECTIVE: To evaluate the association between acute kidney injury (AKI) and long-term survival in lung transplant patients. METHODS: Clinical data of 88 patients who underwent lung transplantation (LTx) were retrospectively analyzed at our institution from September 2002 to December 2011. Postoperative AKI was defined and divided into three groups based on creatinine criteria from the Acute Kidney Injury Net (AKIN) classification. A multivariable logistic regression model evaluated risk factors for AKI. Primary outcome was 5-year mortality. Risk adjusted multivariable COX proportional hazards regression examined the association of AKI with mortality. RESULTS: A total of 47 (53.40%) patients developed AKI (27 with AKIN1, 20 with AKIN2-3) in the first week after LTx. Multivariate analysis showed pre-LT (pre-lung transplant) hypertension (OR 1.37 [0.06-2.68], p=0.041) and mechanical ventilation (OR 0.05 [0.01-0.09], p=0.022) were risk factors for postoperative AKI. Five-year survival rates in the non-AKI, AKIN1, and AKIN2-3 groups were 48.8%, 37.0%, 30.0%, respectively (p=0.041). Adjusted for age, sex, type and cause of LT, hypertension and diabetes, the hazard ratio for death was 1.481 ([1.040-2.107]) for AKI. CONCLUSIONS: The occurrence of AKI after LTx is common. Severe AKI would increase long-term mortality risk. Several variables, including pre-LT hypertension and mechanical ventilation, are associated with AKI after LTx.
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Injúria Renal Aguda/etiologia , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/mortalidade , Injúria Renal Aguda/epidemiologia , Adulto , Idoso , Creatinina/sangue , Cuidados Críticos , Oxigenação por Membrana Extracorpórea , Feminino , Taxa de Filtração Glomerular , Humanos , Hipertensão/complicações , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Respiração Artificial , Estudos Retrospectivos , Fatores de RiscoRESUMO
Developing renewable energy (RE) is the inevitable choice for China to achieve its climate goals. However, financing RE investments remains challenging. Meanwhile, China's digital finance (DF) is profoundly influencing the trajectory of the energy transition. This study empirically investigates the role of DF on the growth of RE, what aspects of DF matter, and its geographical attenuation process, taking both spatial and temporal dimensions into consideration. The empirical results show that DF and its coverage breadth and usage depth can facilitate RE development in both local and neighboring regions, with a comparatively limited effect of digitalization level. The impact of DF on the growth of RE is heterogeneous and has been declining over time. Specifically, this effect is observable only in the eastern regions. The spillover effects of DF on RE development vary in different spatial thresholds, which has clear boundary effects and geographical decay characteristics.
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Clima , Investimentos em Saúde , China , Geografia , Energia Renovável , Desenvolvimento EconômicoRESUMO
The influence of oat lipids on the structural, thermal, rheological, and in vitro digestibility properties of oat starch under heat processing conditions was investigated. X-ray diffraction, fourier infrared spectroscopy, and differential scanning calorimetry revealed the formation of a V-shaped crystal structure between starch and lipid, resulting in enhanced orderliness and enthalpy. Oat lipids decreased the final viscosity and gel strength of oat starch while weakening the trend towards gel network formation. Additionally, oat lipids exhibited enhanced resistance to starch hydrolase, leading to elevated contents of slowly digestible starch and resistant starch. Consequently, this leads to an augmentation in the rate constants for the rapid digestion fraction (k1) and the slow digestion fraction (k2). When the lipid content reached 7.50 %, a significant increase of 42.20 % was observed in the maximum digestibility of slow digestion fraction (C∞2), while a notable decrease of 44.06 % was noted in the maximum digestibility of rapid digestion fraction (C∞1). The correlation analysis revealed that lipid content, final viscosity, and enthalpy exerted significant influences on in vitro starch digestion. These results demonstrate the substantial impact of lipid content on oat starch structure, subsequently affecting its thermal, rheological, and digestive properties.
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Avena , Digestão , Lipídeos , Reologia , Amido , Amido/química , Amido/metabolismo , Avena/química , Viscosidade , Lipídeos/química , Difração de Raios X , Varredura Diferencial de Calorimetria , TemperaturaRESUMO
Oat rice with great sensory acceptance was developed based on the combination method of milling and defatting (petroleum ether) treatment. In this study, the effect of milling and defatting treatment on the texture and digestion properties of oat rice was investigated. Results showed that milling and defatting treatment enhanced stickiness, enthalpy, and starch digestibility. The pasting temperature and hardness of oat rice were reduced. The lipid content of oat rice was significantly reduced by milling and defatting treatment, leading to a decrease in the formation of starch-lipid complex. Fourier transform infrared spectroscopy and X-ray diffraction analyses revealed that the application of milling and defatting treatments led to a reduction in the content of starch-lipid complexes in oats during the cooking process. Milling and defatting significantly enhanced both the rapid and slow digestion rates of oat rice. Specifically, the rapid digestion rate was found to be 2.5 times higher than the slow digestion rate. The nutritive components of oat rice were properly preserved, and the viscosity and elasticity of oat rice reached the maximum when milling for 40 s and defatting. This study provides a theoretical basis for oat products.
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BACKGROUND: In Traditional Chinese Medicine (TCM), tongue diagnosis has been an important diagnostic method for the last 3000 years. Tongue diagnosis is a non-invasive, simple and valuable diagnostic tool. TCM treats the tongue coating on a very sensitive scale that reflects physiological and pathological changes in the organs, especially the spleen and stomach. Tongue coating can diagnose disease severity and determine the TCM syndrome ("Zheng" in Chinese). The biological bases of different tongue coating appearances are still poorly understood and lack systematic investigation at the molecular level. METHODS: Tongue coating samples were collected from 70 chronic gastritis patients and 20 normal controls. 16S rRNA denatured gradient gel electrophoresis (16S rRNA-DGGE) and liquid chromatography and mass spectrometry (LC-MS) were designed to profile tongue coatings. The statistical techniques used were principal component analysis and partial least squares-discriminate analysis. RESULTS: Ten potential metabolites or markers were found in chronic gastritis patients, including UDP-D-galactose, 3-ketolactose, and vitamin D2, based on LC-MS. Eight significantly different strips were observed in samples from chronic gastritis patients based on 16S rRNA-DGGE. Two strips, Strips 8 and 10, were selected for gene sequencing. Strip 10 sequencing showed a 100% similarity to Rothia mucilaginosa. Strip 8 sequencing showed a 96.2% similarity to Moraxella catarrhalis. CONCLUSIONS: Changes in glucose metabolism could possibly form the basis of tongue coating conformation in chronic gastritis patients. The study revealed important connections between metabolic components, microecological components and tongue coating in chronic gastritis patients. Compared with other diagnostic regimens, such as blood tests or tissue biopsies, tongue coating is more amenable to, and more convenient for, both patients and doctors.
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Gastrite/metabolismo , Gastrite/microbiologia , Língua/metabolismo , Língua/microbiologia , Adulto , Estudos de Casos e Controles , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Eletroforese em Gel de Gradiente Desnaturante , Feminino , Humanos , Análise dos Mínimos Quadrados , Masculino , Metaboloma , Pessoa de Meia-Idade , RNA Ribossômico 16S , Língua/químicaRESUMO
Deep reinforcement learning (DRL) policies have been shown to be deceived by perturbations (e.g., random noise or intensional adversarial attacks) on state observations that appear at test time but are unknown during training. To increase the robustness of DRL policies, previous approaches assume that explicit adversarial information can be added into the training process, to achieve generalization ability on these perturbed observations as well. However, such approaches not only make robustness improvement more expensive but may also leave a model prone to other kinds of attacks in the wild. In contrast, we propose an adversary agnostic robust DRL paradigm that does not require learning from predefined adversaries. To this end, we first theoretically show that robustness could indeed be achieved independently of the adversaries based on a policy distillation (PD) setting. Motivated by this finding, we propose a new PD loss with two terms: 1) a prescription gap maximization (PGM) loss aiming to simultaneously maximize the likelihood of the action selected by the teacher policy and the entropy over the remaining actions and 2) a corresponding Jacobian regularization (JR) loss that minimizes the magnitude of gradients with respect to the input state. The theoretical analysis substantiates that our distillation loss guarantees to increase the prescription gap and hence improves the adversarial robustness. Furthermore, experiments on five Atari games firmly verify the superiority of our approach compared to the state-of-the-art baselines.
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The uncertain check-ins bring challenges for current static next point-of-interest (POI) recommendation methods. Fortunately, the conversation-based recommendation has been shown the merit of integrating immediate user preference for more accurate recommendations. We, therefore, propose a conversation-based adaptive relational translation (CART) approach for the next POI recommendation over uncertain check-ins. It is equipped with recommender and conversation modules to interactively acquire users' immediate preferences and make dynamic recommendations. Specifically, the recommender built upon the adaptive relational translation method performs location prediction via modeling both users' historical sequential behaviors and the immediate preference received from conversations; the conversation module aims to achieve successful recommendations in fewer conversation turns by learning a conversational strategy, whereby the recommender can be updated via the user response. Extensive experiments on four real-world datasets show the superiority of our proposed CART over the state of the arts.