First demonstration of 30 eVee ionization energy resolution with Ricochet germanium cryogenic bolometers

The future Ricochet experiment aims to search for new physics in the electroweak sector by measuring the Coherent Elastic Neutrino-Nucleus Scattering process from reactor antineutrinos with high precision down to the sub-100 eV nuclear recoil energy range. While the Ricochet collaboration is currently building the experimental setup at the reactor site, it is also finalizing the cryogenic detector arrays that will be integrated into the cryostat at the Institut Laue Langevin in early 2024. In this paper, we report on recent progress from the Ge cryogenic detector technology, called the CryoCube. More specifically, we present the first demonstration of a 30 eVee (electron equivalent) baseline ionization resolution (RMS) achieved with an early design of the detector assembly and its dedicated High Electron Mobility Transistor (HEMT) based front-end electronics with a total input capacitance of about 40 pF. This represents an order of magnitude improvement over the best ionization resolutions obtained on similar phonon-and-ionization germanium cryogenic detectors from the EDELWEISS and SuperCDMS dark matter experiments, and a factor of three improvement compared to the first fully-cryogenic HEMT-based preamplifier coupled to a CDMS-II germanium detector with a total input capacitance of 250 pF. Additionally, we discuss the implications of these results in the context of the future Ricochet experiment and its expected background mitigation performance.

Electrolyte Design for Low-Temperature Li-Metal Batteries: Challenges and Prospects

Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation. To get the most energy storage out of the battery at low temperatures, improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases. Herein, this review critically outlines electrolytes' limiting factors, including reduced ionic conductivity, large de-solvation energy, sluggish charge transfer, and slow Li-ion transportation across the electrolyte/electrode interphases, which affect the low-temperature performance of Li-metal batteries. Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding. Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared. Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries.

First Measurement of the Nuclear-Recoil Ionization Yield in Silicon at 100 eV

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

[Low-dose helical CT projection data restoration using noise estimation]

OBJECTIVE

To build a helical CT projection data restoration model at random low-dose levels.

METHODS

We used a noise estimation module to achieve noise estimation and obtained a low-dose projection noise variance map, which was used to guide projection data recovery by the projection data restoration module. A filtering back-projection algorithm (FBP) was finally used to reconstruct the images. The 3D wavelet group residual dense network (3DWGRDN) was adopted to build the network architecture of the noise estimation and projection data restoration module using asymmetric loss and total variational regularization. For validation of the model, 1/10 and 1/15 of normal dose helical CT images were restored using the proposed model and 3 other restoration models (IRLNet, REDCNN and MWResNet), and the results were visually and quantitatively compared.

RESULTS

Quantitative comparisons of the restored images showed that the proposed helical CT projection data restoration model increased the structural similarity index by 5.79% to 17.46% compared with the other restoration algorithms (P < 0.05). The image quality scores of the proposed method rated by clinical radiologists ranged from 7.19% to 17.38%, significantly higher than the other restoration algorithms (P < 0.05).

CONCLUSION

The proposed method can effectively suppress noises and reduce artifacts in the projection data at different low-dose levels while preserving the integrity of the edges and fine details of the reconstructed CT images.

High-precision measurement of the W boson mass with the CDF II detector

The mass of the W boson, a mediator of the weak force between elementary particles, is tightly constrained by the symmetries of the standard model of particle physics. The Higgs boson was the last missing component of the model. After observation of the Higgs boson, a measurement of the W boson mass provides a stringent test of the model. We measure the W boson mass, M_W, using data corresponding to 8.8 inverse femtobarns of integrated luminosity collected in proton-antiproton collisions at a 1.96 tera-electron volt center-of-mass energy with the CDF II detector at the Fermilab Tevatron collider. A sample of approximately 4 million W boson candidates is used to obtain [Formula: see text], the precision of which exceeds that of all previous measurements combined (stat, statistical uncertainty; syst, systematic uncertainty; MeV, mega-electron volts; c, speed of light in a vacuum). This measurement is in significant tension with the standard model expectation.

A120 AUTOMATED BOWEL PREPARATION DETECTION WITH DEEP. CONVOLUTIONAL NEURAL NETWORKS

Background

Introduction: Bowel preparation inadequacy has been shown to increase post-colonoscopy colorectal cancer. As such, the USMSTF recommends repeating colonoscopy within 1 year if bowel preparation is inadequate. However, bowel preparation documentation is variable in clinical practice, and physician recommendations adherent to USMTF guidelines are inconsistent.

Aims

Aims: We present an automated computer assisted method using deep convolutional neural networks to detect bowel preparation and adequacy of bowel preparation with the Boston Bowel Preparation Scale (BBPS).

Methods

Methods: We extracted 38523 images of colonic lumen between 2015 and 2017 from screening colonoscopies. Bowel preparation scores were assessed with BBPS. Adequate bowel preparation was defined as BBPS ≥2, and inadequate bowel preparation was defined as BBPS <2. The dataset was split into 26966 images for training, 7704 for validation, and 3853 for testing. Training data was sampled with replacement from a multinomial distribution to balance subclass distributions in each batch. We developed 2 convoluted neural networks (CNN) using PyTorch with a Densenet-169 backbone pre-trained on ImageNet and fine-tuned on our data for classifying adequacy of bowel preparation (binary) and for subclassification of BBPS (multi-class). We used Adam optimiser with an initial learning rate of 3x10^-4 and a scheduler to decay the learning rate of each parameter group by 0.1 every 7 epochs along with focal loss as our criterion for both classifiers.

Results

Results: The overall accuracy on the test data set for BBPS subclassification was 0.91. The sensitivity for BBPS 0, 1, 2 and 3 were 0.84, 0.91, 0.86, and 0.96, respectively. The specificity for BBPS 0, 1, 2, and 3 were 1.00, 0.98, 0.95, and 0.93, respectively. The overall accuracy of the test data set for adequacy of bowel preparation was 0.97. The sensitivity for adequacy of bowel preparation for BBPS <2 and BBPS ≥2 was 0.92 and 0.99, respectively. The specificity for adequacy of bowel preparation for BBPS <2 and BBPS ≥2 was 0.99 and 0.92, respectively.

Conclusions

Conclusion: We present an automated computer-assisted detection method of bowel preparation with deep convolutional neural networks. The algorithm is capable of accurate classification of adequacy of bowel preparation (97%) and subclassification of bowel preparation (91%) with high sensitivity and specificity. This algorithm can be applied to automate documentation of bowel preparation and adequacy of bowel preparation. Additional studies will need to be conducted to demonstrate its applicability in real-time colonoscopy.

Funding Agencies

None

Constraints on Lightly Ionizing Particles from CDMSlite

The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) achieved efficient detection of very small recoil energies in its germanium target, resulting in sensitivity to lightly ionizing particles (LIPs) in a previously unexplored region of charge, mass, and velocity parameter space. We report first direct-detection limits calculated using the optimum interval method on the vertical intensity of cosmogenically produced LIPs with an electric charge smaller than e/(3×10^{5}), as well as the strongest limits for charge ≤e/160, with a minimum vertical intensity of 1.36×10^{-7}  cm^{-2} s^{-1} sr^{-1} at charge e/160. These results apply over a wide range of LIP masses (5  MeV/c^{2} to 100  TeV/c^{2}) and cover a wide range of βγ values (0.1-10^{6}), thus excluding nonrelativistic LIPs with βγ as small as 0.1 for the first time.

Light Dark Matter Search with a High-Resolution Athermal Phonon Detector Operated above Ground

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst)  eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140  MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Local negative permittivity and topological phase transition in polar skyrmions

Topological solitons such as magnetic skyrmions have drawn attention as stable quasi-particle-like objects. The recent discovery of polar vortices and skyrmions in ferroelectric oxide superlattices has opened up new vistas to explore topology, emergent phenomena and approaches for manipulating such features with electric fields. Using macroscopic dielectric measurements, coupled with direct scanning convergent beam electron diffraction imaging on the atomic scale, theoretical phase-field simulations and second-principles calculations, we demonstrate that polar skyrmions in (PbTiO₃)_n/(SrTiO₃)_n superlattices are distinguished by a sheath of negative permittivity at the periphery of each skyrmion. This enhances the effective dielectric permittivity compared with the individual SrTiO₃ and PbTiO₃ layers. Moreover, the response of these topologically protected structures to electric field and temperature shows a reversible phase transition from the skyrmion state to a trivial uniform ferroelectric state, accompanied by large tunability of the dielectric permittivity. Pulsed switching measurements show a time-dependent evolution and recovery of the skyrmion state (and macroscopic dielectric response). The interrelationship between topological and dielectric properties presents an opportunity to simultaneously manipulate both by a single, and easily controlled, stimulus, the applied electric field.

[Application of portable electroencephalograph in patients with epilepsy and establishment of medical platform]

Objective: To provide a portable electroencephalograph that can facilitate long-term monitoring of epilepsy patients outside the hospital, and establish a medical platform for epilepsy data monitoring and treatment. Methods: From June 2018 to October 2019, twenty-nine patients from Huashan Hospital (superior hospital) and Jing'an District Central Hospital (subordinate hospital) of Fudan University were enrolled in the study. Among them, twenty-eight cases were diagnosed with epilepsy and 1 case was epileptic seizure. Electroencephalogram (EEG) was collected by portable electroencephalograph once a week and followed up for three months. The seizure frequency, seizure form, medication type, EEG lead number and positive rate were recorded. Patients' medical records and EEG data were uploaded to the cloud database to build a medical alliance platform. Doctors of different levels of hospitals couldobtain diagnosis and achieve resource sharing based on the platform. The data was statistically analyzed using SPSS 18.0. Results: The EEG data collected by the portable electroencephalograph hadfewer artifacts, complete sleep cycle, and could record the interictaldischarges. Twenty-nine patientsunderwent a total of 148 EEG monitoring during the three-month follow-up. Eighty-five cases of epileptic discharges were detected, and the EEG positive rate was 57.4%. The positive rate of EEG in patients with generalized seizures (84.9%) was higher than that in patients with focal seizures (42.1%) (P<0.01); the positive rate of EEG in patients with 2-3 antiepileptic drugs and patients with frequent seizures within three months were also higher (P<0.05). Doctors in the superior hospital in the platform make diagnosis and treatment suggestions according to the above data. Elevenseizure-free patients and four patients with fewer seizures and discharges were diverted to the community hospital for follow-up. Fourteen patients with poor seizure control and/or continuous epileptic discharges were diverted to the superior hospitalto adjust the medication. Doctors of subordinate hospital acquired the diagnosis and treatment suggestions through the platform, and then strengthened the daily care and follow-up. Conclusion: Combined with a portable electroencephalograph, the current study establishs a medical platform for patients with epilepsy to achieve long-term monitoring and rational use of medical resources.

Synthesis of porous Ag2S-NiCo2S4 hollow architecture as effective electrode material with high capacitive performances

Fabrication of highly reactive and cost-effective electrode materials is a key to efficient functioning of green energy technologies. Decorating redox-active metal sulfides with conductive dopants is one of the most effective approaches to enhance electric conductivity and consequently boost capacitive properties. Herein, hierarchically hollow Ag₂S-NiCo₂S₄ architectures are designed with an enhanced conductivity by a simple solvothermal approach. With the favorable porous characteristics and composition, the optimized Ag₂S-NiCo₂S₄-5 electrode exhibits higher specific capacitance (276.5 mAh g^-1 at a current density of 1 A g^-1), a good rate performance (56.3% capacity retention at 50 A g^-1), and an improved cycling stability (92.4% retention after 2000 cycles). This finding originates from the enhanced charge transportation ability within the hierarchical structure, abundant electroactive sites, and low contact resistance. In addition, a battery supercapacitor device constructed with the Ag₂S-NiCo₂S₄-5 as a positive electrode displays a maximum energy density of 63.3Wh kg^-1 at an energy density of 821.8 W kg^-1 with an excellent cycling stability (89.4% capacity retention after 10 000 cycles). Therefore, the present work puts forward new possibility to develop composite electrodes for energy storage battery-supercapacitor.

N2 plasma-activated NiO nanosheet arrays with enhanced water splitting performance

NiO is a promising electrocatalyst for electrochemical energy conversion due to its rich redox sites, low cost, and ease of synthesis. However, hindered by low electrical conductivity and limited electrocatalytic active sites, bare NiO usually exhibits poor electrochemical performance towards hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we develop an N2 plasma activation approach to simultaneously improve both HER and OER activity of NiO by constructing heterostructured Ni/Ni3N/NiO nanosheet arrays on Ni foam. The optimized N2 plasma-activated NiO nanosheet arrays for HER and OER (denoted as P-NiO-HER and P-NiO-OER) only need an overpotential of 46 and 294 mV, respectively, to achieve 10 mA cm-2. Moreover, for overall water splitting, the assembled electrolysis cell with P-NiO-HER and P-NiO-OER as the cathode and anode, respectively, only requires a small voltage of 1.57 V to deliver 10 mA cm-2. Remarkably, the plasma-activated NiO nanosheet arrays exhibit excellent stability for up to 50 h for HER, OER, and full water electrolysis. The strategy developed here to activate the electrocatalytic performance of metal oxides opens a new door for water splitting.

Electrospinning metal Phosphide/Carbon nanofibers from Phytic Acid for hydrogen evolution reaction catalysts

This paper reports a general electrospinning method to prepare various metal phosphide/carbon nanofibers composite for electrochemical hydrogen evolution reaction (HER) catalysts. An earth-abundant organic acid-phytic acid is successfully incorporated into a conventional electrospinning precursor as the phosphorus source, and continuous nanofibers can be obtained through spinning. After heat treatment, metal phosphide/carbon composite nanofibers can be obtained, with fine phosphide nanoparticles well dispersed on the surface of an interconnected carbon backbone network. Such fibrous structures offer fast charge transfer pathways and enlarged active surface area, which are beneficial for electrocatalysts. As a result, enhance HER catalytic activity can be achieved.

Rational Design of Porous Structured Nickel Manganese Sulfides Hexagonal Sheets-in-Cage Structures as an Advanced Electrode Material for High-Performance Electrochemical Capacitors

The design of hierarchical electrodes comprising multiple components with a high electrical conductivity and a large specific surface area has been recognized as a feasible strategy to remarkably boost pseudocapacitors. Herein, we delineate hexagonal sheets-in-cage shaped nickel-manganese sulfides (Ni-Mn-S) with nanosized open spaces for supercapacitor applications to realize faster redox reactions and a lower charge-transfer resistance with a markedly enhanced specific capacitance. The hybrid was facilely prepared through a two-step hydrothermal method. Benefiting from the synergistic effect between Ni and Mn active sites with the improvement of both ionic and electric conductivity, the resulting Ni-Mn-S hybrid displays a high specific capacitance of 1664 F g^-1 at a current density of 1 A g^-1 and a capacitance of 785 F g^-1 is maintained at a current density of 50 A g^-1 , revealing an outstanding capacity and rate performance. The asymmetric supercapacitor device assembled with the Ni-Mn-S hexagonal sheets-in-cage as the positive electrode delivers a maximum energy density of 40.4 Wh kg^-1 at a power density of 750 W kg^-1 . Impressively, the cycling retention of the as-fabricated device after 10 000 cycles at a current density of 10 A g^-1 reaches 85.5 %. Thus, this hybrid with superior capacitive performance holds great potential as an effective charge-storage material.

Prospects for observing and localizing gravitational-wave transients with Advanced LIGO, Advanced Virgo and KAGRA

We present our current best estimate of the plausible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next several years, with the intention of providing information to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals for the third (O3), fourth (O4) and fifth observing (O5) runs, including the planned upgrades of the Advanced LIGO and Advanced Virgo detectors. We study the capability of the network to determine the sky location of the source for gravitational-wave signals from the inspiral of binary systems of compact objects, that is binary neutron star, neutron star-black hole, and binary black hole systems. The ability to localize the sources is given as a sky-area probability, luminosity distance, and comoving volume. The median sky localization area (90% credible region) is expected to be a few hundreds of square degrees for all types of binary systems during O3 with the Advanced LIGO and Virgo (HLV) network. The median sky localization area will improve to a few tens of square degrees during O4 with the Advanced LIGO, Virgo, and KAGRA (HLVK) network. During O3, the median localization volume (90% credible region) is expected to be on the order of 10 5 , 10 6 , 10 7 Mpc 3 for binary neutron star, neutron star-black hole, and binary black hole systems, respectively. The localization volume in O4 is expected to be about a factor two smaller than in O3. We predict a detection count of 1 - 1 + 12 ( 10 - 10 + 52 ) for binary neutron star mergers, of 0 - 0 + 19 ( 1 - 1 + 91 ) for neutron star-black hole mergers, and 17 - 11 + 22 ( 79 - 44 + 89 ) for binary black hole mergers in a one-calendar-year observing run of the HLV network during O3 (HLVK network during O4). We evaluate sensitivity and localization expectations for unmodeled signal searches, including the search for intermediate mass black hole binary mergers.

Progress and Challenges Toward the Rational Design of Oxygen Electrocatalysts Based on a Descriptor Approach

Oxygen redox catalysis, including the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), is crucial in determining the electrochemical performance of energy conversion and storage devices such as fuel cells, metal-air batteries,and electrolyzers. The rational design of electrochemical catalysts replaces the traditional trial-and-error methods and thus promotes the R&D process. Identifying descriptors that link structure and activity as well as selectivity of catalysts is the key for rational design. In the past few decades, two types of descriptors including bulk- and surface-based have been developed to probe the structure-property relationships. Correlating the current descriptors to one another will promote the understanding of the underlying physics and chemistry, triggering further development of more universal descriptors for the future design of electrocatalysts. Herein, the current benchmark activity descriptors for oxygen electrocatalysis as well as their applications are reviewed. Particular attention is paid to circumventing the scaling relationship of oxygen-containing intermediates. For hybrid materials, multiple descriptors will show stronger predictive power by considering more factors such as interface reconstruction, confinement effect, multisite adsorption, etc. Machine learning and high-throughput simulations can thus be crucial in assisting the discovery of new multiple descriptors and reaction mechanisms.

Recent Trends in Synthesis and Investigation of Nickel Phosphide Compound/Hybrid-Based Electrocatalysts Towards Hydrogen Generation from Water Electrocatalysis

Sustainable and high performance energy devices such as solar cells, fuel cells, metal-air batteries, as well as alternative energy conversion and storage systems have been considered as promising technologies to meet the ever-growing demands for clean energy. Hydrogen evolution reaction (HER) is a crucial process for cost-effective hydrogen production; however, functional electrocatalysts are potentially desirable to expedite reaction kinetics and supply high energy density. Thus, the development of inexpensive and catalytically active electrocatalysts is one of the most significant and challenging issues in the field of electrochemical energy storage and conversion. Realizing that advanced nanomaterials could engender many advantageous chemical and physical properties over a wide scale, tremendous efforts have been devoted to the preparation of earth-abundant transition metals as electrocatalysts for HER in both acidic and alkaline environments because of their low processing costs, reasonable catalytic activities, and chemical stability. Among all transition metal-based catalysts, nickel compounds are the most widely investigated, and have exhibited pioneering performances in various electrochemical reactions. Heterostructured nickel phosphide (Ni_xP_y) based compounds were introduced as promising candidates of a new category, which often display chemical and electronic characteristics that are distinct from those of non-precious metals counterparts, hence providing an opportunity to construct new catalysts with an improved activity and stability. As a result, the library of Ni_xP_y catalysts has been enriched very rapidly, with the possibility of fine-tuning their surface adsorption properties through synergistic coupling with nearby elements or dopants as the basis of future practical implementation. The current review distils recent advancements in Ni_xP_y compounds/hybrids and their application for HER, with a robust emphasis on breakthroughs in composition refinement. Future perspectives for modulating the HER activity of Ni_xP_y compounds/hybrids, and the challenges that need to be overcome before their practical use in sustainable hydrogen production are also discussed.

MicroRNA 34b inhibits cell proliferation in pediatric acute myeloid leukemia via regulating LDHA

OBJECTIVE

To elucidate the regulatory effect of microRNA-34b on the occurrence of pediatric acute myeloid leukemia and the underlying mechanism.

PATIENTS AND METHODS

The expression of microRNA-34b in the bone marrow of 72 children with newly diagnosed acute myeloid leukemia (AML) was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The relationship between microRNA-34b expression and pathological characteristics was analyzed. Kaplan-Meier curve was introduced for evaluating the prognostic value of microRNA-34b in pediatric AML. The regulatory effects of microRNA-34b on proliferation, cell cycle, and apoptosis of leukemia cells were accessed by cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. Bioinformatics prediction and dual-luciferase reporter gene assay were conducted to evaluate the binding between microRNA-34b and lactate dehydrogenase A (LDHA). LDHA expression after overexpression of microRNA-34b was determined by qRT-PCR and Western blot. Rescue experiments were conducted to verify whether microRNA-34b could regulate proliferative and apoptotic behaviors of leukemia cells by suppressing LDHA expression.

RESULTS

MicroRNA-34b was markedly downregulated in AML children. Low expression of microRNA-34b was correlated to FAB typing, cytogenetic abnormality, and day 7 response to the treatment of pediatric AML. By collecting the follow-up data, it was found that low expression of microRNA-34b was correlated to the poor prognosis of AML. Overexpression of microRNA-34b inhibited proliferative ability and cell cycle progression, but accelerated apoptosis of AML cells. Dual-luciferase reporter gene assay verified that microRNA-34b could bind to LDHA, thereafter inhibiting LDHA expression. Overexpression of LDHA reversed the regulatory effects of microRNA-34b on proliferation, cell cycle, and apoptosis of AML cells.

CONCLUSIONS

We found that microRNA-34b is lowly expressed in pediatric AML patients, and low expression of microRNA-34b may serve as an indicator of malignant progression and poor prognosis of pediatric AML. MicroRNA-34b may affect the proliferation and apoptosis of leukemia cells by regulating the expression of LDHA.

Sponge Effect Boosting Oxygen Reduction Reaction at the Interfaces between Mullite SmMn2O5 and Nitrogen-Doped Reduced Graphene Oxide

Exploring the effect of interfacial structural properties on catalytic performance of hybrid materials is essential in rationally designing novel electrocatalysts with high stability and activity. Here, in situ growth of mullite SmMn₂O₅ on nitrogen-doped reduced graphene oxide (SMO@NrGO) is achieved for highly efficient oxygen reduction reaction (ORR). Combining X-ray photoelectron spectroscopy and density functional theory calculations, interfacial chemical interactions between Mn and substrates are verified. Interestingly, as revealed by charge density difference, the interfacial Mn-N(C) bonds display a sponge effect to store and compensate electrons to boost the ORR process. In addition, bidentate adsorption of oxygen intermediates instead of monodentate ones is observed in hybrid materials, which facilitates the interactions between intermediates and active sites. Experimentally, the hybrid catalyst SMO@NrGO exhibits a half-wave potential as high as 0.84 V, being comparable to benchmark Pt/C and higher than that of the pure SMO (0.68 V). The Zn-air battery assembled with SMO@NrGO shows a high discharge peak power density of 244 mW cm^-2 and superior cycling stability against noble metals.

Optical creation of a supercrystal with three-dimensional nanoscale periodicity

Stimulation with ultrafast light pulses can realize and manipulate states of matter with emergent structural, electronic and magnetic phenomena. However, these non-equilibrium phases are often transient and the challenge is to stabilize them as persistent states. Here, we show that atomic-scale PbTiO₃/SrTiO₃ superlattices, counterpoising strain and polarization states in alternate layers, are converted by sub-picosecond optical pulses to a supercrystal phase. This phase persists indefinitely under ambient conditions, has not been created via equilibrium routes, and can be erased by heating. X-ray scattering and microscopy show this unusual phase consists of a coherent three-dimensional structure with polar, strain and charge-ordering periodicities of up to 30 nm. By adjusting only dielectric properties, the phase-field model describes this emergent phase as a photo-induced charge-stabilized supercrystal formed from a two-phase equilibrium state. Our results demonstrate opportunities for light-activated pathways to thermally inaccessible and emergent metastable states.

Kinetic control of tunable multi-state switching in ferroelectric thin films

Deterministic creation of multiple ferroelectric states with intermediate values of polarization remains challenging due to the inherent bi-stability of ferroelectric switching. Here we show the ability to select any desired intermediate polarization value via control of the switching pathway in (111)-oriented PbZr_0.2Ti_0.8O₃ films. Such switching phenomena are driven by kinetic control of the volume fraction of two geometrically different domain structures which are generated by two distinct switching pathways: one direct, bipolar-like switching and another multi-step switching process with the formation of a thermodynamically-stable intermediate twinning structure. Such control of switching pathways is enabled by the competition between elastic and electrostatic energies which favors different types of ferroelastic switching that can occur. Overall, our work demonstrates an alternative approach that transcends the inherent bi-stability of ferroelectrics to create non-volatile, deterministic, and repeatedly obtainable multi-state polarization without compromising other important properties, and holds promise for non-volatile multi-state functional applications.

The use of ferroeletric materials for multi-state device applications is still challenging. Here, the authors present a mechanism to stabilize non-volatile polarization states by populating volume fractions of two domain structures in PbZr_0.2Ti_0.8O₃ via kinetic control of switching pathways.

Erratum: First Dark Matter Constraints from a SuperCDMS Single-Charge Sensitive Detector [Phys. Rev. Lett. 121, 051301 (2018)]

This corrects the article DOI: 10.1103/PhysRevLett.121.051301.

Fe ions modulated formation of hollow NiFe oxyphosphide spheres with enhanced oxygen evolution performance

Hollow NiFe oxyphosphide spheres are synthesized based on a facile template-engaged strategy with different Fe ions as modulators and exhibit excellent alkaline OER performance.

Synthesis of 3D hierarchical porous Ni–Co layered double hydroxide/N-doped reduced graphene oxide composites for supercapacitor electrodes

In this work, three-dimensional porous Ni–Co layered double hydroxide nanosheets are vertically decorated on N-doped reduced graphene oxide via a simple one-step microwave-assisted hydrothermal process.

MiR-410 regulates malignant biological behavior of pediatric acute lymphoblastic leukemia through targeting FKBP5 and Akt signaling pathway

OBJECTIVE

The aim of this study was to investigate the role of miR-410 in regulating the proliferation and apoptosis of pediatric acute lymphoblastic leukemia (ALL) cells and to explore the possible underlying mechanism.

PATIENTS AND METHODS

The expression level of miR-410 in ALL cases and cells was detected by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR). Luciferase reporter gene assay was performed to evaluate the interaction between miR-410 and FKBP5. MTT and colony formation assay were used to determine the effect of miR-410 on the proliferation and colony formation ability of ALL cells. The effect of miR-410 on cell apoptosis was measured by Annexin V-fluorescein isothiocyanate 1 (FITC) and propidium iodide (PI). Western blot was used to analyze the effect of miR-410 on the protein expression levels of phosphorylated Akt (p-Akt) and cleaved caspase-3.

RESULTS

In our investigation, miR-410 was significantly up-regulated in ALL cases and cells. We searched three public databases to predict the potential target of miR-410, and found that FKBP5 was a direct target of miR-410. Meanwhile, Luciferase reporter gene assay confirmed our hypothesis. The overexpression of miR-410 accelerated the proliferation and colony formation ability of ALL cells, whereas remarkably decreased cell apoptosis rate. Western blotting showed that miR-410 inhibited the activation of Akt signaling pathway. However, FKBP5 could reverse the effects of miR-410.

CONCLUSIONS

MiR-410 regulated the proliferation, colony formation and apoptosis of ALL cells through targeting FKBP5 and Akt signal pathway, indicating that miR-410 might be a potential therapeutic target for the treatment of ALL.

First Dark Matter Constraints from a SuperCDMS Single-Charge Sensitive Detector

We present the first limits on inelastic electron-scattering dark matter and dark photon absorption using a prototype SuperCDMS detector having a charge resolution of 0.1 electron-hole pairs (CDMS HVeV, a 0.93 g CDMS high-voltage device). These electron-recoil limits significantly improve experimental constraints on dark matter particles with masses as low as 1  MeV/c^{2}. We demonstrate a sensitivity to dark photons competitive with other leading approaches but using substantially less exposure (0.49 g d). These results demonstrate the scientific potential of phonon-mediated semiconductor detectors that are sensitive to single electronic excitations.

Assessment of left atrial function and dyssynchrony by real time three-dimensional echocardiography predicts recurrence of paroxysmal atrial fibrillation after radiofrequency ablation

OBJECTIVE

Left atrial volume and function are associated with recurrence of paroxysmal atrial fibrillation (AF) after radiofrequency ablation. A relationship between left atrial mechanical dyssynchrony and AF recurrence is presently unclear. The aim of this study was to investigate whether left atrial volume, function, and dyssynchrony were associated with AF recurrence in patients with normal left ventricular function, and normal or mildly enlarged left atrium, if assessed by the Real-time three-dimensional echocardiography (3DE).

PATIENTS AND METHODS

We included 88 patients with AF who had their first pulmonary vein isolation. There were 67 patients without and 21 patients with AF recurrence after radiofrequency ablation. Real-time 3DE was performed in the sinus rhythm the day before radiofrequency ablation. Left atrial volumes (maximum, minimum and preA), functions (passive, active and reservoir) and dyssynchrony were calculated. The latter was quantified by the standard deviation of time to minimum systolic volume (Tmsv-SD) from the end-diastole.

RESULTS

There was no difference between left atrial volume and function in patients with or without AF recurrence. However, significant differences in left atrial Tmsv-SD were observed in patients with AF recurrence.

CONCLUSIONS

In patients with normal left ventricular function, and normal/mildly enlarged left atrium, left atrial Tmsv-SD assessment by Real-time 3DE is a useful predictor of AF recurrence after radiofrequency ablation.

Cobalt sulfide aerogel prepared by anion exchange method with enhanced pseudocapacitive and water oxidation performances

This work introduces the anion exchange method into the sol-gel process for the first time to prepare a metal sulfide aerogel. A porous Co₉S₈ aerogel with a high surface area (274.2 m² g^-1) and large pore volume (0.87 cm³ g^-1) has been successfully prepared by exchanging cobalt citrate wet gel in thioacetamide and subsequently drying in supercritical ethanol. Such a Co₉S₈ aerogel shows enhanced supercapacitive performance and catalytic activity toward oxygen evolution reaction (OER) compared to its oxide aerogel counterpart. High specific capacitance (950 F g^-1 at 1 A g^-1), good rate capability (74.3% capacitance retention from 1 to 20 A g^-1) and low onset overpotential for OER (220 mV) were observed. The results demonstrated here have implications in preparing various sulfide chalcogels.

Search for the Exotic Meson X(5568) with the Collider Detector at Fermilab

A search for the exotic meson X(5568) decaying into the B_{s}^{0}π^{±} final state is performed using data corresponding to 9.6  fb^{-1} from pp[over ¯] collisions at sqrt[s]=1960  GeV recorded by the Collider Detector at Fermilab. No evidence for this state is found and an upper limit of 6.7% at the 95% confidence level is set on the fraction of B_{s}^{0} produced through the X(5568)→B_{s}^{0}π^{±} process.

Nano Titanium Monoxide Crystals and Unusual Superconductivity at 11 K

Nano TiO₂ is investigated intensely due to extraordinary photoelectric performances in photocatalysis, new-type solar cells, etc., but only very few synthesis and physical properties have been reported on nanostructured TiO or other low valent titanium-containing oxides. Here, a core-shell nanoparticle made of TiO core covered with a ≈5 nm shell of amorphous TiO_1+x is newly constructed via a controllable reduction method to synthesize nano TiO core and subsequent soft oxidation to form the shell (TiO_1+x ). The physical properties measurements of electrical transport and magnetism indicate these TiO@TiO_1+x nanocrystals are a type-ІІ superconductor of a recorded T_c^onset = 11 K in the binary Ti-O system. This unusual superconductivity could be attributed to the interfacial effect due to the nearly linear gradient of O/Ti ratio across the outer amorphous layer. This novel synthetic method and enhanced superconductivity could open up possibilities in interface superconductivity of nanostructured composites with well-controlled interfaces.