Sub-Nanometer Channels Embedded in Two-Dimensional Materials

Two-dimensional (2D) materials are among the most promising candidates for next-generation electronics due to their atomic thinness, allowing for flexible transparent electronics and ultimate length scaling. Thus far, atomically-thin p-n junctions, metal-semiconductor contacts, and metal-insulator barriers have been demonstrated. While 2D materials achieve the thinnest possible devices, precise nanoscale control over the lateral dimensions is also necessary. Here, we report the direct synthesis of sub-nanometer-wide 1D MoS2 channels embedded within WSe2 monolayers, using a dislocation-catalyzed approach. The 1D channels have edges free of misfit dislocations and dangling bonds, forming a coherent interface with the embedding 2D matrix. Periodic dislocation arrays produce 2D superlattices of coherent MoS2 1D channels in WSe2. Using molecular dynamics simulations, we have identified other combinations of 2D materials where 1D channels can also be formed. The electronic band structure of these 1D channels offer the promise of carrier confinement in a direct-gap material and charge separation needed to access the ultimate length scales necessary for future electronic applications.Comment: 22 pages main manuscript and methods, 4 main figures, 30 pages supplementary materials, 16 extended figure

Clinical characteristics of two patients with neuronal intranuclear inclusion disease and literature review

BackgroundNeuronal intranuclear inclusion disease (NIID) is a rare chronic progressive neurodegenerative disease, with complex and diverse clinical manifestations and pathological eosinophilic hyaline intranuclear inclusions in the central and peripheral nervous systems and visceral organs. Improvements in diagnostic methods such as skin biopsy and gene testing are helpful in revealing the clinical and genetic characters of NIID.Materials and methodsWe presented two cases of NIID diagnosed by using NOTCH2NLC gene testing and skin biopsy. Diffusion weighted imaging (DWI) showed high linear intensity in corticomedullary junction. We also reviewed all the published NIID cases with positive NOTCH2NLC GGC repeat expansion and skin biopsy results in PubMed.ResultsPatient 1 was a 63-year-old male who carried 148 GGC repeats and presented with progressive tremor and limb weakness. Patient 2 was a 62-year-old woman who carried 131 GGC repeats and presented with tremors, memory loss and headaches. The most common clinical manifestation of 63 NIID patients in this study was cognitive impairment, followed by tremors. In our study, almost all the patients were from East Asia, the male to female ratio was 1:1.26, with an age of onset of 54.12 ± 14.12 years, and an age of diagnosis of 60.03 ± 12.21 years. Symmetrical high signal intensity at the corticomedullary junction on DWI were revealed in 80.96% of the patients. For the GGC repeat numbers, the majority of GGC repeats were in the 80–119 intervals, with few GGC repeats above 160. The number of GGC repetitions was significantly higher in patients presented with muscle weakness than in other clinical manifestations.ConclusionNIID is a neurodegenerative disease caused by aberrant polyglycine (polyG) protein aggregation. NIID mostly occurs in the elderly population in East Asia, with cognitive dysfunction as the most common symptom. Staging NIID based on clinical presentation is inappropriate because most patients with NIID have overlapping symptoms. In our study, there was no significant correlation between the number of GGC repeats and different phenotypes except for muscle weakness. Abnormal trinucleotides repeat and PolyG protein aggregation maybe common pathogenic mechanism in neurodegenerative diseases and cerebrovascular diseases, which needs to be confirmed by more studies

Janus monolayers of transition metal dichalcogenides.

Structural symmetry-breaking plays a crucial role in determining the electronic band structures of two-dimensional materials. Tremendous efforts have been devoted to breaking the in-plane symmetry of graphene with electric fields on AB-stacked bilayers or stacked van der Waals heterostructures. In contrast, transition metal dichalcogenide monolayers are semiconductors with intrinsic in-plane asymmetry, leading to direct electronic bandgaps, distinctive optical properties and great potential in optoelectronics. Apart from their in-plane inversion asymmetry, an additional degree of freedom allowing spin manipulation can be induced by breaking the out-of-plane mirror symmetry with external electric fields or, as theoretically proposed, with an asymmetric out-of-plane structural configuration. Here, we report a synthetic strategy to grow Janus monolayers of transition metal dichalcogenides breaking the out-of-plane structural symmetry. In particular, based on a MoS2 monolayer, we fully replace the top-layer S with Se atoms. We confirm the Janus structure of MoSSe directly by means of scanning transmission electron microscopy and energy-dependent X-ray photoelectron spectroscopy, and prove the existence of vertical dipoles by second harmonic generation and piezoresponse force microscopy measurements

Design and optimization of an advanced time-of-flight neutron spectrometer for deuterium plasmas of the large helical device

A time-of-flight neutron spectrometer based on the Time-Of-Flight Enhanced Diagnostic (TOFED) concept has been designed and is under development for the Large Helical Device (LHD). It will be the first advanced neutron spectrometer to measure the 2.45 MeV D–D neutrons (DDNs) from helical/stellarator plasmas. The main mission of the new TOFED is to study the supra-thermal deuterons generated from the auxiliary heating systems in helical plasmas by measuring the time-of-flight spectra of DDN. It will also measure the triton burnup neutrons (TBNs) from the d+t reactions, unlike the original TOFED in the EAST tokamak. Its capability of diagnosing the TBN ratios is evaluated in this work. This new TOFED is expected to be installed in the basement under the LHD hall and shares the collimator with one channel of the vertical neutron camera to define its line of sight. The distance from its primary scintillators to the equatorial plane of LHD plasmas is about 15.5 m. Based on Monte Carlo simulation by a GEANT4 model, the resolution of the DDN energy spectra is 6.6%. When projected onto the neutron rates that are typically obtained in LHD deuterium plasmas (an order of 1015 n/s with neutral beam injection), we expect to obtain the DDN and TBN counting rates of about 2.5 · 105 counts/s and 250 counts/s, respectively. This will allow us to analyze the DDN time-of-flight spectra on time scales of 0.1 s and diagnose the TBN emission rates in several seconds with one instrument, for the first time in helical/stellarator plasmas

Investigation on solar assisted liquid desiccant dehumidifier and evaporative cooling system for fresh air treatment.

The widely used semi-centralized air conditioning (A/C) system consisting of independent fresh air system and fan coil system suffers from huge energy consumption, especially for fresh air treatment. Therefore, a liquid desiccant dehumidifier and regenerative indirect evaporative cooling (LDD-RIEC) system is proposed for fresh air treatment. The fresh air is handled by the LDD-RIEC system in which no electricity-intensive compressor involves. The hot and humid fresh air is firstly dehumidified by LDD and then sensibly cooled by RIEC. The thermal energy captured by solar collectors is used for desiccant solution regeneration. Indoor return air is cooled by fan coils of a mechanical cooling system. The system performance is analyzed by solving the heat and mass transfer equations of each component integrally in a closed loop. Focus is placed on discussing the influences of solar collector area and inlet air conditions, and optimizing the extraction air ratio of RIEC. The energy saving ratio is quantitatively evaluated with respect to a conventional A/C system. Results reveal that the optimal extraction ratio is 0.3 considering the interacted influence of dehumidifier, regenerator, RIEC and solar collector. The energy saving ratio ranges from 22.4% to 53.2% under various inlet air conditions

How Do Online Reviews Affect App Performance? From the Perspective of Sentiment Analysis

With the prevalence of mobile applications (Apps), it is of significance to investigate the critical factors affecting their performance among customers, such as their rankings in the App store. This research investigates the effects of online reviews’ sentiment (i.e., sentiment valence and intensity) on App performance. What makes this study unique is that we also consider the influence of App updates on the relationship between online review sentiment and App performance. With the data acquired from the App store, we test our research model. We found that the proportion of positive reviews has a negative correlation with App performance, while the proportion of negative reviews has an inverted U-shape relationship with App performance. In addition, for negative reviews with high sentiment intensity, we found that App updates mask the relationship between sentiment intensity and App performance. Theoretical contribution and managerial implications of this research are discussed

Risk preferences in self-other decisions: The effect of payoff allocation framing

The effect of framing is well established: Decision makers&#39; preferences are influenced by how outcomes or attributes are phrased. In the financial domain, individuals often make decisions for themselves and for others. Therefore, decisions in a two-person context with the outcome equally allocated can be framed in two ways defined as theallocation framing: (1) self-allocation frame: making a decision for oneself, with half the payoffs shared by another person; and (2) other-allocation frame: making a decision for the other person and sharing half the payoffs. The results of six studies provided consistent evidence that people are more risk seeking in the self-allocation frame than in the other-allocation frame, and the effect was only noteworthy in the gain domain-not the loss domain. Our findings on allocation framing provide a meaningful contribution to studies of self-other decision making.</p

Investigation on the Regeneration and Corrosion Characteristics of an Anodized Aluminum Plate Regenerator

The traditional vapor compression cooling system (VCS) has been criticized for its heavy reliance on electricity consumption and limited control ability of humidity. Compared with the VCS, the liquid desiccant cooling system (LDCS) is more efficient by handling the sensible and latent load separately. The present study investigated the regeneration and corrosion characteristics of an anodized aluminum plate regenerator for the first time. Comparative tests were conducted to present the regeneration and corrosion characteristics of the normal and anodized regenerator. The influence of internal heating on the regeneration performance was also identified. The results showed that the corrosion rate was reduced from 0.0005218 mm/year for normal aluminum to 0.000011 m/year for anodized one under the same operating conditions. However, pitting corrosion was observed at operating conditions with high solution temperature, as the anodized layer of anodized aluminum was damaged due to the high temperature. Compared with the normal aluminum regenerator, the anodized one had an average enhancement of 24% and 23.7% in terms of regeneration rate and effectiveness, respectively. It was attributed to the increment of surface energy from 26.4 mN/m for normal aluminum to 47.6 mN/m for anodized plate. Besides, it was found that, compared with adiabatic one, the internally-heated regenerator improved the regeneration rate by 6.0%~38% and the regeneration effectiveness by 6.3%~32% depending on the operating conditions. The advantage of present study is that it can guide the design of anodized aluminum regenerator for LDCS