Summary
Modelling cyclic behaviour of granular soils under both drained and undrained conditions with a good performance is still a challenge. This study presents a new way of modelling the cyclic ...behaviour of granular materials using deep learning. To capture the continuous cyclic behaviour in time dimension, the long short‐term memory (LSTM) neural network is adopted, which is characterised by the prediction of sequential data, meaning that it provides a novel means of predicting the continuous behaviour of soils under various loading paths. Synthetic datasets of cyclic loading under drained and undrained conditions generated by an advanced soil constitutive model are first employed to explore an appropriate framework for the LSTM‐based model. Then the LSTM‐based model is used to estimate the cyclic behaviour of real sands, ie, the Toyoura sand under the undrained condition and the Fontainebleau sand under both undrained and drained conditions. The estimates are compared with actual experimental results, which indicates that the LSTM‐based model can simultaneously simulate the cyclic behaviour of sand under both drained and undrained conditions, ie, (a) the cyclic mobility mechanism, the degradation of effective stress and large deformation under the undrained condition, and (b) shear strain accumulation and densification under the drained condition.
Selenocysteine (Sec, pKa 5.8) is genetically encoded 21st amino acid into the active site of selenoproteins, which have broad functions relevant to various diseases, tissues or organs and subcellular ...organelles. However, many selenoproteins involved cellular functions still remains unclear. In addition, since biothiols such as glutathione (GSH, pKa 8.3), possessing similar chemical properties with Sec, commonly exist in living systems at high levels. Thus, it is of great importance and high challenge to identify novel probes for selectively monitoring Sec over biothiols. In this paper, we proposed a smart strategy which allowed us to develop a lysosome targetable probe for specifically sensing Sec. By restricting weak acidic microenvironment, the probe shows a specific detection for Sec with 85-fold fluorescence enhancement owing to the remaining high activity of Sec at pH 5.0. Moreover, being low cytotoxicity to the cells verified by MTS assay, the probe was then successfully applied for imaging exogenous and endogenous Sec in lysosomes, indicating its potential for the biological investigation of Sec in subcellular organelles.
A smart strategy which allowed us to develop a lysosome targetable probe for specifical sensing Sec over biothiols. Display omitted
•Highly selective sensing selenocysteine over biothiols at pH 5.0.•An 85-fold response with a detection limit of 0.38 μM.•Synergetic effect of acid induced ring opening and selenocysteine caused cleavage reaction.•Imaging of the endogenous selenol-containing molecule and exogenous selenocysteine.
Highly efficient multi-resonance thermally activated delayed fluorescence (MR-TADF) emitters with narrowband emissions based on a boron/nitrogen (B/N) framework are crucial for next-generation ...full-color displays with high color purity. In this work, we develop a simple molecular design strategy for MR-TADF materials based on a skeleton of phenoxazine units and amplification at the
para
-position of the boron atom by different electron-donating groups (phenoxazine/
tert
-butylcarbazole). Two novel phenoxazine-fused MR-TADF materials, TPXZBN and DPXZCZBN, show green emissions with sharp peaks at 502 nm and 500 nm, with small full-width at half maximum (FWHM) bandwidths of 33 nm and 32 nm, respectively. TPXZBN and DPXZCZBN also exhibit small singlet-triplet state energy gaps (Δ
E
st
s) of 0.16 eV and 0.13 eV, with high photoluminescence quantum yields (PLQYs) of 91% and 90% in toluene solutions, and 99% and 94% in doped films, respectively. The corresponding organic light-emitting diodes (OLEDs) based on TPXZBN and DPXZCZBN exhibited maximum external quantum efficiencies (EQE
max
s) of 21.3% and 19.8%, respectively, accompanied by small efficiency roll-offs, with EQEs of 17.2% and 18.8% at 100 cd m
−2
, and 17.4% and 19.6% at 1000 cd m
−2
, respectively. Notably, the small electroluminescence FWHMs of the OLEDs still remained at 37 nm and 36 nm, respectively.
Two phenoxazine fused MR-TADF materials based on a B/N framework show high PLQYs and small FWHMs in toluene solutions, while their OLEDs exhibit EQEs of up to 21.3% with small efficiency roll-offs and narrow EL emissions.
Anlotinib, a novel orally administered multitargeted tyrosine kinase inhibitor, inhibiting tumor angiogenesis and growth, significantly prolonged overall survival, and progression-free survival with ...a manageable safety profile as a third-line therapy among refractory advanced nonsmall cell lung cancer (NSCLC) patients in ALTER 0303 trail (NCT02388919).
Two squamous cell lung cancer patients with mediastinal metastasis undergoing the treatment of anlotinib developed clinical symptom of cough, which was worse upon ingestion.
On the basis of patients' clinical symptoms and radiographic findings, they were diagnosed with acquired esophago-tracheobronchial fistula.
We treated them with fully covered self-expandable metallic stents.
The clinical symptom of cough was immediately relieved after palliative treatment. Both patients elected to discontinue anlotinib treatment.
These 2 cases imply that a close follow-up schedule for esophago-tracheobronchial fistula should be established when squamous cell lung cancer patients with mediastinal metastasis are undergoing anlotinib therapy. Early detection and adequate treatment are essential for patient symptom relief and survival.
In the urgent campaign to develop therapeutics against SARS-CoV-2, natural products have been an important source of new lead compounds.
We herein identified two natural products, ginkgolic acid and ...anacardic acid, as inhibitors using a high-throughput screen targeting the SARS-CoV-2 papain-like protease (PL
). Moreover, our study demonstrated that the two hit compounds are dual inhibitors targeting the SARS-CoV-2 3-chymotrypsin-like protease (3CL
) in addition to PL
. A mechanism of action study using enzyme kinetics further characterized the two compounds as irreversible inhibitors against both 3CL
and PL
. Significantly, both identified compounds inhibit SARS-CoV-2 replication in vitro at nontoxic concentrations.
Our finding provides two novel natural products as promising SARS-CoV-2 antivirals.
Compression index Cc is an essential parameter in geotechnical design for which the effectiveness of correlation is still a challenge. This paper suggests a novel modelling approach using machine ...learning (ML) technique. The performance of five commonly used machine learning (ML) algorithms, i.e. back-propagation neural network (BPNN), extreme learning machine (ELM), support vector machine (SVM), random forest (RF) and evolutionary polynomial regression (EPR) in predicting Cc is comprehensively investigated. A database with a total number of 311 datasets including three input variables, i.e. initial void ratio e0, liquid limit water content wL, plasticity index Ip, and one output variable Cc is first established. Genetic algorithm (GA) is used to optimize the hyper-parameters in five ML algorithms, and the average prediction error for the 10-fold cross-validation (CV) sets is set as the fitness function in the GA for enhancing the robustness of ML models. The results indicate that ML models outperform empirical prediction formulations with lower prediction error. RF yields the lowest error followed by BPNN, ELM, EPR and SVM. If the ranges of input variables in the database are large enough, BPNN and RF models are recommended to predict Cc. Furthermore, if the distribution of input variables is continuous, RF model is the best one. Otherwise, EPR model is recommended if the ranges of input variables are small. The predicted correlations between input and output variables using five ML models show great agreement with the physical explanation.
This paper suggests a novel modelling approach using machine learning (ML) technique. The performance of five commonly used machine learning (ML) algorithms, i.e. back-propagation neural network (BPNN), extreme learning machine (ELM), support vector machine (SVM), random forest (RF) and evolutionary polynomial regression (EPR) in predicting Cc is comprehensively investigated. The results indicate that ML models outperform empirical prediction formulations with lower prediction error. RF yields the lowest error followed by BPNN, ELM, EPR and SVM. If the ranges of input variables in the database are large enough, BPNN and RF models are recommended to predict Cc. Furthermore, if the distribution of input variables is continuous, RF model is the best one. Display omitted
•Novel machine learning based models are proposed for predicting compression index of clays.•The performance of five commonly used machine learning algorithms in predicting Cc is comprehensively investigated.•BPNN and RF models are recommended to predict the compression index of clays.
•Modeling methods of frost heave models for the past 50 years were deconstructed.•Error sources of each coupling components of the models were analyzed.•Regarding freezing soil as porous medium ...causes water migration error.•Error sources of the model can be hidden by coupling components error.
Frost heave models are important tools to study engineering damage in cold regions. However, multi-physical-field-coupling and different methods of coupling components bring difficulties to compare the models and to optimize their error sources. Therefore, classifying and deconstructing of different frost heave models and further evaluating them are significant for model development. We reviewed frost heave models for the past 50 years and built frost heave model families to show the classification and inheritance relationships. Then, the models were deconstructed by the thermal–hydraulic framework (THF) and frost heave quantification method (FHQM). Finally, based on simulated and experimental data in cited papers, the model errors caused by different THFs and FHQMs were analyzed. The results show: (a) Present frost heave models can be classified as porosity increase based (P) and ice lens increase based (I) models and they are tending to merge with each other; (b) THFs of P models regarding freezing soil as porous medium are the main reason for water migration error in the region of multi-ice layers, which also results high uncertainty of hydraulic parameters under different simulation conditions; (c) The most used two FHQMs of P models cause error exceeding 20 % because inaccurate relationship between pore strain and frost heave displacement; (d) The errors of THFs and FHQMs offset each other, which will hidden the error sources of the models. This paper can provide a reference for the improvement of frost heave models used in engineering.
To characterize the clinical and pathological features and survival of patients with human epidermal growth factor receptor 2 (HER2)-low breast cancer in China.
The China National Cancer Center ...database was used to identify 1,433 metastatic breast cancer patients with HER2-negative disease diagnosed between 2005 and 2015. Clinicopathological features, survival, and prognosis information were extracted. Overall survival (OS) was estimated using the Kaplan-Meier method and compared using the log-rank test. Prognostic factors associated with OS were analyzed using Cox regression model with 95% confidence interval (95% CI).
There were 618 (43.1%) and 815 (56.9%) HER2-low and HER2-zero tumors out of 1,433 tumors, respectively. The proportion of hormone receptor (HR)-positive tumors was significantly higher in HER2-low tumors than in those with HER2-zero tumors (77.8% vs. 69.2%,
< 0.001). Patients with HER2-low tumors survived significantly longer than those with HER2-zero tumors in the overall population (48.5 months vs. 43.0 months,
= 0.004) and HR-positive subgroup (54.9 months vs. 48.1 months,
= 0.011), but not in the HR-negative subgroup (29.5 months vs. 29.9 months,
= 0.718). Multivariate regression analysis revealed that HER2-low tumors were independently associated with increased OS in HER2-negative population (HR: 0.85, 95% CI: 0.73-0.98,
= 0.026).
Our findings demonstrate that HER2-low tumors could be identified as a more distinct clinical entity from HER2-zero tumors, especially for the HR-positive subgroup. A more complex molecular landscape of HER2-low breast cancer might exist, and more precise diagnostic algorithms for HER2 testing could be investigated, thus offering new therapeutic targets for breast cancer treatment.
Circularly polarized organic light-emitting diodes (CP-OLEDs) have received considerable attention due to their promising applications in 3D displays. However, up to now, CP-OLEDs using iridium(
iii
...) phosphors as emissive dopants exhibited low brightness, insufficient efficiency, serious efficiency roll-off, and especially low electroluminescence dissymmetry factors (
g
EL
). In this study, a blue Ir(
iii
) complex Ir(dfppy)
2
(sdpp) (dfppy is 2-(2,4-difluorophenyl)pyridine, sdpp is pyridinylphosphorothioate) peaking at 466 nm was synthesized, and two pairs of enantiomers containing the λ or δ isomer together with a chiral phosphine center (
R
or
S
) were separated into λ-Ir(dfppy)
2
(
S
-sdpp), δ-Ir(dfppy)
2
(
R
-sdpp), λ-Ir(dfppy)
2
(
R
-sdpp) and δ-Ir(dfppy)
2
(
S
-sdpp), respectively. It is the first example to investigate phosphine chirality in an Ir(
iii
) complex, and the electron cloud distribution in the chiral conjugated ancillary ligand and λ/δ chirality of the Ir(
iii
) center induced Ir(dfppy)
2
(sdpp) to exhibit decent circularly polarized luminescence (CPL) activities with a dissymmetry factor (|
g
PL
|) around 1.4 × 10
−3
. The OLEDs based on Ir(dfppy)
2
(sdpp) exhibited a maximum external quantum efficiency of 13.8% with mild efficiency roll-off. Notably, the CP-OLEDs based on λ-Ir(dfppy)
2
(
S
-sdpp), δ-Ir(dfppy)
2
(
R
-sdpp), λ-Ir(dfppy)
2
(
R
-sdpp) and δ-Ir(dfppy)
2
(
S
-sdpp) showed obvious circularly polarized electroluminescence (CPEL) signals with a
g
EL
of −2.1 × 10
−3
, 2.4 × 10
−3
, −2.1 × 10
−3
and 1.9 × 10
−3
, respectively, thus affording an efficient strategy for the design of chiral blue Ir(
iii
) emitters and their CP-OLEDs.
A blue Ir(
iii
) complex with double chiral centers based on the λ or δ isomer together with a chiral phosphine center (
R
or
S
) can be separated into four isomers, which can show obvious CPL intensity and CPEL properties.
In this work, two cyclometalated ligands 2-(pyridin-2-yl)indolo3,2,1-
jk
carbazole (pyidcz) and 2-(4-(trifluoromethyl)pyridin-2-yl)indolo3,2,1-
jk
carbazole (tfpyidcz) containing an indolo3,2,1-
jk
...carbazole unit were synthesized for achieving highly efficient iridium(
iii
) complexes (pyidcz)
2
Ir(tmd) and (tfpyidcz)
2
Ir(tmd) (tmd = 2,2,6,6-tetramethyl-3,5-heptanedione). The two Ir(
iii
) complexes exhibit emissions peaking at 499 and 554 nm, respectively, with narrow full width at half maximum (FWHM) values of 35 and 53 nm, respectively, short phosphorescence lifetimes less than 1 μs and high photoluminescence quantum yields of up to 90% in CH
2
Cl
2
solution. The organic light-emitting diodes (OLEDs) with (pyidcz)
2
Ir(tmd) and (tfpyidcz)
2
Ir(tmd) emitters show good performances. The (pyidcz)
2
Ir(tmd)-based device shows a turn-on voltage (
V
on
) of 3.6 V with a maximum brightness (
L
max
) of 39123 cd m
−2
, a maximum current efficiency (
η
c,max
) of 69.2 cd A
−1
, a maximum power efficiency (
η
p,max
) of 36.8 lm W
−1
and a maximum external quantum efficiency (EQE
max
) of 21.2%. In particular, the FWHM bandwidth of the electroluminescence spectrum is only 33 nm, which was rarely reported for Ir(
iii
) complex-based OLEDs. The performance of the (tfpyidcz)
2
Ir(tmd)-based device is slightly better with a
V
on
of 3.3 V, a
L
max
of 31714 cd m
−2
, a
η
c,max
of 78.4 cd A
−1
, a
η
p,max
of 54.7 lm W
−1
and an EQE
max
of 24.0%. Furthermore, the efficiency roll-offs of both devices are small, and the
η
c
values at 10 000 cd m
−2
brightness are still maintained at 60.0 and 71.4 cd A
−1
, respectively, which provide a powerful reference for developing indolo3,2,1-
jk
carbazole-based Ir(
iii
) complexes for efficient OLEDs.
OLEDs based on iridium(
iii
) complexes containing an indolo3,2,1-
jk
carbazole unit exhibit good emission performances with a narrow full width at half maximum of 33 nm, good efficiency and low efficiency roll-off.
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