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The Zintl compound Mg3Sb2 is a promising thermoelectric material with Earth-abundant components. Compared to its n-type counterpart, p-type Mg3Sb2 reveals lower dimensionless figure of merit (zT), ...

BACKGROUND: An increased focus on patient-reported outcome measures (PROMs) has led to a proliferation of these measures in orthopaedic surgery. Mandating a single PROM in clinical and research orthopaedics is not feasible given the breadth of data already collected with older measures and the emergence of psychometrically superior measures. Creating crosswalk tables for scores between measures allows providers to maintain control of measure choice. Furthermore, crosswalk tables permit providers to compare scores collected with older outcome measures with newly collected ones. Given the widespread use of the newer Patient-reported Outcome Measure Information System Physical Function (PROMIS PF) and the established Knee Outcome and Osteoarthritis Score (KOOS), it would be clinically useful to link these two measures.QUESTION/PURPOSE: Can the KOOS Function in Activities of Daily Living (ADL) subscale be robustly linked to the PROMIS PF to create a crosswalk table of equivalent scores that accurately reflects a patient's reported physical function level on both scales?METHODS: We sought to establish a common standardized metric for collected responses to the PROMIS PF and the KOOS ADL to develop equations for converting a PROMIS PF score to a score for the KOOS-ADL subscale and vice versa. To do this, we performed a retrospective, observational study at two academic medical centers and two community hospitals in an urban and suburban healthcare system. Patients 18 years and older who underwent TKA were identified. Between January 2017 and July 2020, we treated 8165 patients with a TKA, 93% of whom had a diagnosis of primary osteoarthritis. Of those, we considered patients who had completed a full KOOS and PROMIS PF 10a on the same date as potentially eligible. Twenty-one percent (1708 of 8165) of patients were excluded because no PROMs were collected at any point, and another 67% (5454 of 8165) were excluded because they completed only one of the required PROMs, leaving 12% (1003 of 8165) for analysis here. PROMs were collected each time they visited the health system before and after their TKAs. Physical function was measured by the PROMIS PF version 1.0 SF 10a and KOOS ADL scale. Analyses to accurately create a crosswalk of equivalent scores between the measures were performed using the equipercentile linking method with both unsmoothed and log linear smoothed score distributions.RESULTS: Crosswalks were created, and adequate validation results supported their validity; we also created tables to allow clinicians and clinician scientists to convert individual patients' scores easily. The mean difference between the observed PROMIS PF scores and the scores converted by the crosswalk from the KOOS-ADL scores was -0.08 ± 4.82. A sensitivity analysis was conducted, confirming the effectiveness of these crosswalks to link the scores of two measures from patients both before and after surgery.CONCLUSION: The PROMIS PF 10a can be robustly linked to the KOOS ADL measure. The developed crosswalk table can be used to convert PROMIS PF scores from KOOS ADL and vice versa.CLINICAL RELEVANCE: The creation of a crosswalk table between the KOOS Function in ADL subscale and PROMIS PF allows clinicians and researchers to easily convert scores between the measures, thus permitting greater choice in PROM selection while preserving comparability between patient cohorts and PROM data collected from older outcome measures. Creating a crosswalk, or concordance table, between the two scales will facilitate this comparison, especially when pooling data for meta-analyses.

BACKGROUND CONTEXT: When different health care providers use different patient-reported outcome (PRO) instruments, it is challenging to integrate findings that describe particular patient groups or to establish treatment effectiveness across studies. It is therefore critical to develop accurate ways to convert scores between various instruments for clinicians and researchers to make comparisons across health outcomes.PURPOSE: To develop a common metric so that scores on the Oswestry Disability Index (ODI) and scores on the PROMIS Physical Function can be converted interchangeably.STUDY DESIGN/SETTING: Data were collected from a prospective study. A single-group linking design was used.PATIENT SAMPLE: The study population included 9020 patients presented to an orthopedic spine clinic from November 2013 to March 2019.OUTCOME MEASURES: Patients completed the ODI and the PROMIS Pain Interference scale delivered by Computerized Adaptive Testing (CAT) at the same time prior to their visit with a spine clinician.METHODS: Equipercentile linking methods based on log-linear smoothing approach and non-smoothing approach were used to establish a common metric across the two measures.RESULTS: The two measures assess the similar contruct of pain. The correlation between the scores of the ODI and the PROMIS PI was 0.81. The standardized Root Expected Mean Square Difference (REMSD) values for gender, ethnic, and racial groups ranged from 3.55% to 4.81%. Hence, the assumptions for the equipercentile linking method were met. The crosswalk derived linked scores based on the log-linear smoothing method yielded small deviations (Δ = 0.09) from the observed scores. We then identified linked PROMIS-PI scores corresponding to the benchmark ODI scores for the five disability levels and for various categories of patients.CONCLUSIONS: This study is the first to create crosswalks to interchangeably convert scores between the ODI to the PROMIS-PI in a large population of spine patients using the equipercentile linking method. The results of this study provide confidence in the validity and usefulness of the derived crosswalks based on the equipercentile linking approach. The crosswalks are helpful for comparing new and old studies on the two measures and identifying benchmark scores for various diseases and disability levels.

Achieving high thermoelectric power factor in thin film heterostructures is essential for integrated and miniaturized thermoelectric device applications. In this work, we demonstrate a mechanism to enhance thermoelectric power factor through coupling the interfacial confined two-dimensional electron gas (2DEG) with thin film conductivity in a transition metal dichalcogenides-SrTiO3 heterostructure. Owing to the formed conductive interface with two-dimensional electron confinement effect and the elevated conductivity, the ZrTe2/SrTiO3 (STO) heterostructure presents enormous thermoelectric power factor as high as 4×10^5 μW cm^(-1) K^(-2) at 20 K and 4800 μW cm^(-1) K^(-2) at room temperature. Interfacial reaction induced degradation of Ti cations valence number from Ti4+ to Ti3+ is attributed to be responsible for the formation of the quasi-two-dimensional electrons at the interface which results in very large Seebeck coefficient; and the enhanced electrical conductivity is suggested to be originated from the charge transfer induced doping in the ZrTe2. By taking the thermal conductivity of STO substrate as a reference, the effective zT value of this heterostructure can reach 15 at 300 K. This superior thermoelectric property makes this heterostructure a promising candidate for future thermoelectric device, and more importantly, paves a new pathway to design promising high-performance thermoelectric systems.

Intense, polarization controllable, and single-cycle terahertz pulses as light source are important tools to investigate physical and biological properties of materials. In this paper, we have detected efficient terahertz emission from layered transition-metal pentatelluride ZrTe5 excited by femtosecond laser pulse due to its strong anisotropy and high mobility of electrons. The physical mechanism of terahertz generation from this material is studied and the absolute predominance of diffusion current induced by photo-Dember effect is proved. In addition, we have achieved the modulation of terahertz polarization by adjusting the polarization states of the pump pulse. The generated elliptically polarized THz pulse is crucial for the investigation of vibration modes of chiral biological molecules, such as proteins and DNAs. Our findings indicate that strong and polarization-controllable THz emission can be generated by ZrTe5.

SnSe single crystals have been demonstrated to possess excellent thermoelectric properties. In this work, we demonstrate a grain size control method in growing nanocrystalline SnSe thin films through a glancing angle pulsed-laser deposition approach. Structural characterization reveals that the SnSe film deposited at a normal angle has a preferred orientation along a axis, while by contrast, the SnSe film deposited at an 80° glancing angle develops a nanopillar structure with the growth direction towards the incident atomic flux. The glancing angle deposition greatly reduces the grain size of the thin film due to a shadowing effect to the adatoms, resulting in significantly increased power factor for more than 100%. The maximum Seebeck coefficient and power factor are 498.5 μ V / K and 18.5 μ W c m − 1 K − 2 , respectively. The enhancement of thermoelectric property can be attributed to the potential barrier scattering at grain boundaries owing to the reduced grain size and increased grain boundaries in the film. Given this enhanced power factor, and considering the fact that the nanopillar structure should have much lower thermal conductivity than a plain film, the zT value of such made SnSe film could be significantly larger than the corresponding single crystal film, making it a good candidate for thin film-based thermoelectric device.

An artificial synapse, such as a memristive electronic synapse, has caught world-wide attention due to its potential in neuromorphic computing, which may tremendously reduce computer volume and energy consumption. The introduction of layered two-dimensional materials has been reported to enhance the performance of the memristive electronic synapse. However, it is still a challenge to fabricate large-area layered two-dimensional films by scalable methods, which has greatly limited the industrial application potential of two-dimensional materials. In this work, a scalable pulsed laser deposition (PLD) method has been utilized to fabricate large-area layered SnSe films, which are used as the functional layers of the memristive electronic synapse with dual modes. Both long-term memristive behaviour with gradually changed resistance (Mode 1) and short-term memristive behavior with abruptly reduced resistance (Mode 2) have been achieved in this SnSe-based memristive electronic synapse. The switching between Mode 1 and Mode 2 can be realized by a series of voltage sweeping and programmed pulses. The formation and recovery of Sn vacancies were believed to induce the short-term memristive behaviour, and the joint action of Ag filament formation/rupture and Schottky barrier modulation can be the origin of long-term memristive behaviour. DFT calculations were performed to further illustrate how Ag atoms and Sn vacancies diffuse through the SnSe layer and form filaments. The successful emulation of synaptic functions by the layered chalcogenide memristor fabricated by the PLD method suggests the application potential in future neuromorphic computers.

The coming Big Data Era requires progress in storage and computing technologies. As an emerging memory technology, Resistive RAM (RRAM) has shown its potential in the next generation high-density storage and neuromorphic computing applications, which extremely demand low switching voltage and power consumption. In this work, a 10 nm-thick amorphous GeS2 thin film was utilized as the functional layer of RRAM in a combination with Ag and Pt electrodes. The structure and memory performance of the GeS2-based RRAM device was characterized — it presents high on/off ratio, fast switching time, ultralow switching voltage (0.15 V) and power consumption (1.0 pJ and 0.56 pJ for PROGRAM and ERASE operations, respectively). We attribute these competitive memory characteristics to Ag doping phenomena and subsequent formation of Ag nano-islands in the functional layer that occurs due to diffusion of Ag from electrode into the GeS2 thin film. These properties enable applications of GeS2 for low energy RRAM device.

Cr2Ge2Te6-based compounds with a layered structure and high symmetry hold a great promise for thermoelectric applications. Our studies have been committed to improve their electrical properties considering the low power factor of only ∼0.23 mW/mK2 in pristine samples. In this work, various doping contents on the site that has less influence on the charge-conducting band have been investigated to enhance the power factor. The results show that Fe-doping is the most favorable among elements we applied. According to the first-principles calculation, the Fe doping on the Cr site leads to the increment of the density of states around the Fermi level. By tuning the carrier concentration via Fe doping, the peak power factor rises from 0.23 mW/mK2 to 0.37 mW/mK2 and zT rises from 0.3 to 0.4 at 830 K for Cr1.9Fe0.1Ge2Te6 along the pressing direction. These results shed lights for designing high performance thermoelectric materials.

MTHFR C677T and A1298C have been associated with the risk of preeclampsia (PE), but with conflicting results. We performed this meta-analysis to derive a more precise estimation of the association between MTHFR polymorphisms and PE. An electronic search of PubMed and Chinese Biomedicine database was conducted to select studies for meta-analysis. 54 case controlled studies containing MTHFR C677T and A1298C gene polymorphisms were chosen, and odds ratio (OR) with confidence interval (CI) was used to assess the strength of this association. These studies evaluated 7398 cases and 11230 controls for MTHFR C677T. The overall results suggested that MTHFR C677T was associated with the risk of PE. (T vs. C: OR = 1.157, 95 % CI: 1.057-1.266, p=0.002; TT+CT vs. CC: OR=1.165, 95 % CI : 1.049-1.293, P = 0.004; TT vs. CT + CC: OR = 1.371, 95 % CI: 1.153-1.63, p < 0.001). We also evaluated 1103 cases and 988 controls for MTHFR A1298C but could not demonstrate an increased risk of PE for this polymorphism (p=0.667). A symmetric funnel plot, the Egger’s test (p = 0.819) suggested a lack of publication bias. This meta-analysis supports the idea that MTHFR C677T genotype is associated with increased risk for PE, especially in the case of Asians and Caucasians.

Projectors have become very popular in school classrooms in China. However traditional lighting design does not consider lighting influence on the visibility of projection screen. The aim of this study was to investigate the current lighting conditions in classrooms when watching a projection screen, and then to search for lighting conditions providing better visibility. A survey was carried out to collect desk illuminance, projection screen luminance and contrast from eight schools in four cities in China. Based on the survey, an experiment was designed and performed with three ambient illumination conditions (i.e., 0lux, 300lux, daylight), five different projection screen luminance levels (i.e., 50, 100, 150, 200, 260 cd/m2), and five seating positions. The results indicate that the ambient illumination, the projection screen luminance, and the seating position all have a significant influence on the visibility of gratings on the projection.

There are many different guidelines on illumination level for work with VDTs. Most of the previous work put their focus on professional spaces with high desktop illuminance. For low illuminance environment, it is not fully studied on VDTs. For example, many home lighting conditions have illuminance below 100lux, comparing with 500lux in office. The adaptation condition for visual comfort may yield different preference. It is in general understood that offering a certain amount of background light could be a solution to help relieve eye fatigue. However home background may become very different from the background defined in previous experiments with the assumption of a wall close to the display. It is not clear by having a wall in distance from the display, whether or not same level of visual comfort as having a wall close by can still be realized with back lighting. In this study we investigated the background influence on visual comfort levels by comparing illuminated VDT background ‘with wall’ and ‘without wall’ at home, using no back lighting as the control condition. The results suggest that even with a wall in distance, back lighting can still be effective to improve visual comfort and relieve eye fatigue for computer use at home.

Background & Aims Acetaminophen (APAP) is widely used as an antipyretic agent which is safe at therapeutic doses. However, overdose of APAP induces fatal and non-fatal hepatic necroses. The chemical reactive metabolites of APAP initiate toxicity and inflammatory response within the liver and lead to acute liver failure. However, the mechanism underlying APAP-induced liver injury is unknown. Thioredoxin-1 (TRX-1) is an important redox regulator, which plays roles in resisting oxidative stress, regulating inflammation and inhibiting apoptosis. Panaxatriol saponin (PTS) is one of the biologically active fractions of Panax notoginseng which is a traditional Chinese medicine. The aim of this study was to investigate the mechanism on PTS protecting liver from APAP hepatotoxicity. Methods Mice were divided into three groups, control group, APAP group and APAP combined with PTS group. Alanine aminotransferase (ALT) and tumour necrosis factor-alpha (TNF-α) were detected by ELISA. TRX-1 and pro-caspase-12 were examined by Western blotting. Results Our results showed PTS inhibited the levels of ALT and TNF-α by APAP. Pretreatment with PTS ameliorated liver injury induced by APAP. The decrease in TRX-1 expression was restored by PTS, as well as decreased pro-caspase-12 expression was inhibited by PTS. These data suggest that PTS has roles in suppressing the hepatotoxicity by APAP. Conclusion Panaxatriol saponin ameliorated liver injury by APAP through restoring the expression TRX-1 and inhibiting pro-caspase-12 decrease.

Background The aim of this study is to expand existing knowledge about the CRC-associated microbiome among Han Chinese, and to further discover the variation pattern of the human CRC microbiome across all population. Findings Using pyrosequencing-based molecular monitoring of bacterial 16S rRNA gene from eight tumor/normal tissue pairs of eight Chinese CRC patients, we analyzed and characterized the basic features of the CRC-associated microbiome. Firstly, we discovered an increasing diversity among tumor-associated bacterial communities. Secondly, in 50% of Chinese CRC patients, we found a significant increase of Roseburia (P = 0.017), and a concurrent decrease of both Microbacterium (P = 0.009) and Anoxybacillus (P = 0.009) in tumor tissue. Conclusions We discovered a novel CRC microbiome pattern in Chinese. Both the over-represented Roseburia bacteria at tumor sites and the over-represented Microbacterium and Anoxybacillus bacteria away from tumor sites were both closely related in Chinese CRC patients. Across several populations reported in this study and previously, we observed both common and distinctive patterns of human CRC microbiome’s association with a high-risk of CRC.

Background Both genetic and epigenetic alterations have been reported to act as driving forces of tumorigenesis in colorectal cancer (CRC), but a growing body of evidence suggests that intestinal microbiota may be an aetiological factor in the initiation and progression of CRC. Recently, the “driver-passenger” model for CRC has connected these different factors, but little has been done to characterize the CRC gut microbiome. Findings Building on the driver-passenger model, we used 454 pyrosequencing of bacterial 16S rRNA genes associated with 10 normal, 10 adenoma, and 8 tumor biopsy samples, and found 7 potential driver bacterial genera and 12 potential passenger bacterial genera (7 being pro-inflammatory and 5 anti-inflammatory). Further analysis also showed certain co-expression patterns among different clusters of bacteria that may potentially be related to the promotion or progression of gut cancers. Conclusions The present findings provide preliminary experimental evidence supporting the proposition of bacterial “driver-passenger model” for CRC, and identified potentially novel microbial agents that may be connected to risk of CRC in a Han Chinese population.