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We have performed high-resolution angle-resolved photoemission spectroscopy of layered chalcogenide 1T-FexTa1-xS2 which undergoes a superconducting transition in the nearly commensurate charge-density-wave phase (melted Mott phase). We found a single electron pocket at the Brillouin-zone center in the melted Mott phase, which is created by the backfolding of bands due to the superlattice potential of charge-density-wave. This electron pocket appears in the x region where the samples show superconductivity, and is destroyed by the Mott- and Anderson-gap opening. Present results suggest that the melted Mott state and the superconductivity coexist in real space, providing a new insight into the interplay between electron correlation, charge order, and superconductivity. [ABSTRACT FROM AUTHOR]

Abstract: Layered misfit cobaltite Bi2Ca2.4Co2O y has been synthesized by a sol–gel method. This compound exhibits large thermoelectric (TE) power (S 300K∼170μVK−1), low resistivity (ρ 300K∼42mΩcm) and relatively small thermal conductivity (κ 300K∼2.8WK−1 m−1) at room temperature. Furthermore, the resistivity of this compound displays a metallic behavior above T ⁎∼150K with a semiconducting behavior below this temperature. This abnormal behavior in resistivity is analogous to those observed in Sr and Ba based misfit cobaltites. The observed features of the TE have been discussed based on the narrow band model. [Copyright &y& Elsevier]

Abstract: We present the results of a systematic study of thermoelectric power at zero field and applied magnetic field in the nonmagnetic Y- and magnetic Ho-doped manganites La0.9−x Y (Ho) x Te0.1MnO3 (). For samples, an additional positive magnetothermoelectric power (MTEP) is induced by Y and Ho doping below Curie temperature besides a large negative MTEP in the vicinity of . The Ho-doped compounds have larger resistivity and larger compared to the Y-doped compounds in the same concentration. The magnetic disorder introduced by Ho doping can play an important role in affecting the electronic and thermal transport properties of the sample. [Copyright &y& Elsevier]

Abstract: The resistivity , and thermoelectric power (TEP) in the manganite La0.85Te0.15Mn0.9Cu0.1O3 have been investigated systematically in the absence and presence of magnetic fields. A large negative magnetoresistance (MR) appears up to 5 T. In addition, of the sample shows an anomalous peak, which is suggested to be related to the contribution of phonon drag. Particularly, the thermally induced and the field-induced sign change of S below the Curie temperature is observed, implying the importance of spin polarization. In terms of the change of electronic structure, the orbital degree of freedom of the carriers can be responsible for the effective lifting of the degenerate band. Additionally, based on the fitting results of and , the transport mechanism for the sample in the paramagnetic (PM) insulting region and low-temperature ferromagnetic (FM) insulating region below is suggested to be dominated by variable-range-hopping (VRH) conduction. However, in the intermediate-temperature FM metallic region below , the transport mechanism is considered to be dominated mainly electron–magnon scattering. [Copyright &y& Elsevier]

Abstract: A series of the double-doping samples La(2+4 x )/3Sr(1−4 x )/3Mn1– x Cu x O3 with the Mn3+/Mn4+ ratio fixed at 2:1 and the single-doping samples La2/3Sr1/3Mn1– x Cu x O3 have been investigated. For the double-doping samples, though the ratio Mn3+/Mn4+=2:1 has been generally recognized the optimum ratio, the Curie temperature and metallic–insulator transition temperature are more rapidly decreased by Cu substitution than that corresponding to single-doping samples. And the resistivity value for the double doping is larger about two or three orders of magnitude than that corresponding to single doping. At the same time, two resistivity peaks and two magnetoresistance (MR) peaks appear. We suggest that for the double-doping samples the A-site cation size 〈r A〉 and the A-site mismatch factor decreases with increasing doping level, which leads to the system microstructural distortion. This microstructural distortion makes the Mn3+–O–Mn4+ cut off more cluster-spin except for the clusters induced by Cu. These cluster interfaces contribute to , which exceeds far the contribution of eg electron decreasing with doping increasing in the single doping. At the same time, such interface scattering also gives rise to the appearance of second peak for the double-doping samples. The experimental results shows that double doping could be also a potential way in tuning colossal MR (CMR), which can give a guide for the adequate selection of CMR materials. [Copyright &y& Elsevier]

Abstract: The magnetization, resistivity ρ, thermoelectric power (TEP) S, and thermal conductivity κ in perovskite cobalt oxide Gd0.7Sr0.3CoO3 have been investigated systematically. Based on the temperature dependence of susceptibility χ g(T) and Seebeck coefficient S(T), a combination of the intermediate-spin (IS) state for Co3+ and the low-spin (LS) state for Co4+ can be suggested. A metal–insulator transition (MIT) caused by the hopping of σ* electrons (localized or delocalized e g electrons) from the IS Co3+ to the LS Co4+ is observed. Meanwhile, S(T) curve also displays an obvious phonon drag effect. In addition, based on the analysis of the temperature dependence of S(T) and ρ(T), the high-temperature small polaron conduction and the low-temperature variable-range-hopping conduction are suggested, respectively. As to thermal conduction κ(T), rather low κ values in the whole measured temperature range is attributed to unusually large local Jahn–Teller (JT) distortion of Co3+O6 octahedra with IS state. [Copyright &y& Elsevier]

Abstract: Systematic studies of resistivity, thermoelectric power, and thermal conductivity have been performed on polycrystalline bilayered manganites LaSr2Mn2−x Cr x O7 (0≤x≤0.2). It is found that the temperature dependence of both Seebeck coefficient S(T) and resistivity ρ(T) in the high temperature region follows the small polaron transport mechanism for all the samples. But in the low temperature region, variable-range-hopping (VRH) model matches the experimental data better. In addition, the maximum of absolute S(T) at low temperatures is gradually suppressed for the sample with Cr-doping level of x>0.04, implying that a new FM order probably arises. With decreasing the temperatures further, S(T) has a sign change and becomes positive for the sample with Cr-doping level of x>0.04, indicating that there may occur a variation of the type of charge carrier. As to thermal conduction κ(T), the low-temperature peak is suppressed due to Cr-doping. The variation of κ(T) is analyzed based on the combined effect due to the suppression of local Mn3+O6 Jahn–Teller (JT) lattice distortion because of the substitution of Cr3+ ions for Mn3+ ions, which results in the increase in thermal conduction, and the introduction of the disorder due to Cr-doping, which contributes to the decrease in thermal conduction. [Copyright &y& Elsevier]

Land use and land cover (LULC) changes that occurred during 1992–2011 in Sagarmatha National Park, a United Nations Educational, Scientific, and Cultural Organization World Heritage Site in the Himalayas of eastern Nepal, were evaluated using multitemporal satellite imagery in combination with land use data and sociological information gathered from semistructured interviews and workshops. We asked study participants about LULC changes, the causes of each change, and the likely duration of its effects, and used this information to produce high-resolution maps of local perceptions of LULC change. Satellite image analysis revealed that above 6000 m there has been a decrease in the area covered by snow and ice and a consequent expansion of glacial lakes and areas covered by rock and soil. Between 3000 and 6000 m, forest and farmland are decreasing, and areas under grazing, settlement, and shrubland are increasing. Such LULC changes within the protected area clearly indicate the prevailing danger of land degradation. Results from the interviews and workshops suggest that people tended to detect LULC change that was acute and direct, but were less aware of slower changes that could be identified by satellite imagery analysis. Most study participants said that land use changes were a result of rapid economic development and the consequent pressure on natural resources, especially in the tourism industry and especially below 6000 m elevation, as well as limitations to protected area management and a period of civil war. Human influence coupled with climate change may explain the changes at higher elevations, whereas anthropogenic activities are solely responsible in lower areas. Although global factors cannot be mitigated locally, many of the local drivers of LULC change could be addressed with improved management practices that aid local conservation and development in this high mountain ecosystem. A broader interdisciplinary approach to LULC change should include a mix of satellite image analysis and local observations.

Introduction: Ensuring correct medications are prescribed for all patients admitted with neck of femur fractures is essential for presurgical optimisation, analgesia and perioperative care. This quality improvement project examines patients over the age of 65 who were managed following the orthogeriatric pathway for all neck of femur fractures at Queen Elizabeth Hospital, Woolwich. Guidelines exist that include a list of medications that should be prescribed for all of such patients on admission, including VTE prophylaxis, analgesia, antiemetics, laxatives, IV fluids and preload. The aim is to improve the rate of following this guidance on prescription by clerking doctors on admission. Method: Data was collected retrospectively for all patients admitted to Queen Elizabeth Hospital between 03.12.19–15.01.20 with a neck of femur fracture. Interventions were then introduced to improve medication prescriptions and took place at the start of February 2020. This involved tutorial sessions and raising awareness through posters. Data collection for cycle 1 following interventions took place from 03.02.20–14.03.20 and can be compared with the original baseline data set. Results: Data was collected from 34 patients for the baseline population and 28 patients in Cycle 1. Baseline data suggests that certain medications, such as preload and TEDs stockings were often missed by the admissions team, with only 8.82% of patients receiving 9 pm preload, 17.6% receiving 6 am preload and 38.2% prescribed TED stockings. Following interventions, medication prescriptions by the clerking doctors improved in all parameters, with significant improvements seen with VTE prophylaxis. Conclusion: Induction sessions and accessible guidelines are essential to ensure guidelines are followed and patients receive correct medications on admission. Improving medication prescriptions is vital for medical optimisation prior to surgery and to lower rates of perioperative complications. Clerking doctors responsible for this task should receive correct training and support to ensure this is done correctly. [ABSTRACT FROM AUTHOR]

Robert Edward Ang, Rosalie Mae M Reyes, Maria Luisa P Solis Asian Eye Institute, Rockwell Center, Makati City, Philippines Abstract: We report on a 72 year-old pseudophakic patient who had been implanted with a monofocal intraocular lens, and who underwent a unilateral Supracor laser-assisted in-situ keratomileusis (LASIK) procedure to correct presbyopia and hyperopia. Uncorrected near visual acuity was improved, but the patient complained of glare, halo, reduced distance vision, and poor night driving vision due to treatment decentration. One year following the surgery, a reversal procedure was conducted with a wavefront-guided aspheric treatment to reverse the presbyopic correction while still maintaining the hyperopic correction. This resulted in 20/25 uncorrected distance visual acuity, and it eliminated the dysphotopsia symptoms. We believe that this is the first reported case demonstrating the ability to reverse the Supracor LASIK presbyopic procedure using wavefront-guided treatment in a case of an unsatisfactory outcome. Keywords: presbyopic, Supracor, LASIK, reversal

Anti-pollution flashover of insulator is important for power systems. In recent years, haze-fog weather occurs frequently, which makes discharge occurs easily on the insulator surface and accelerates insulation aging of insulator. In order to study the influence of haze-fog on the surface discharge of room temperature vulcanized silicone rubber, an artificial haze-fog lab was established. Based on four consecutive years of insulator contamination accumulation and atmospheric sampling in haze-fog environment, the contamination configuration appropriate for RTV-coated surface discharge test under simulation environment of haze-fog was put forward. ANSYS Maxwell was used to analyze the influence of room temperature vulcanized silicone rubber surface attachments on electric field distribution. The changes of droplet on the polluted room temperature vulcanized silicone rubber surface and the corresponding surface flashover voltage under alternating current (AC), direct current (DC) positive polar (+), and DC negative polar (−) power source were recorded by a high speed camera. The results are as follows: The main ion components from haze-fog atmospheric particles are NO3−, SO42−, NH4+, and Ca2+. In haze-fog environment, both the equivalent salt deposit density (ESDD) and non-soluble deposit density (NSDD) of insulators are higher than that under general environment. The amount of large particles on the AC transmission line is greater than that of the DC transmission line. The influence of DC polarity power source on the distribution of contamination particle size is not significant. After the deposition of haze-fog, the local conductivity of the room temperature vulcanized silicone rubber surface increased, which caused the flashover voltage reduce. Discharge is liable to occur at the triple junction point of droplet, air, and room temperature vulcanized silicone rubber surface. After the deformation or movement of droplets, a new triple junction point would be formed, which would seriously reduce the dielectric strength of room temperature vulcanized silicone rubber.

Detection and localization of partial discharge are very important in condition monitoring of power cables, so it is necessary to build an accurate recognizer to recognize the discharge types. In this paper, firstly, a power cable model based on FDTD simulation is built to get the typical discharge signals as training samples. Secondly, because the extraction of discharge signal features is crucial, fractal characteristics of the training samples are extracted and inputted into the recognizer. To make the results more accurate, multi-SVM recognizer made up of six Support Vector Machines (SVM) is proposed in this paper. The result of the multi-SVM recognizer is determined by the vote of the six SVM. Finally, the BP neural networks and ELM are compared with multi-SVM. The accuracy comparison shows that the multi-SVM recognizer has the best accuracy and stability, and it can recognize the discharge type efficiently.

To elucidate the mechanisms of fruit body development in H. marmoreus, a total of 43609521 high-quality RNA-seq reads were obtained from four developmental stages, including the mycelial knot (H-M), mycelial pigmentation (H-V), primordium (H-P) and fruiting body (H-F) stages. These reads were assembled to obtain 40568 unigenes with an average length of 1074 bp. A total of 26800 (66.06%) unigenes were annotated and analyzed with the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Eukaryotic Orthologous Group (KOG) databases. Differentially expressed genes (DEGs) from the four transcriptomes were analyzed. The KEGG enrichment analysis revealed that the mycelium pigmentation stage was associated with the MAPK, cAMP, and blue light signal transduction pathways. In addition, expression of the two-component system members changed with the transition from H-M to H-V, suggesting that light affected the expression of genes related to fruit body initiation in H. marmoreus. During the transition from H-V to H-P, stress signals associated with MAPK, cAMP and ROS signals might be the most important inducers. Our data suggested that nitrogen starvation might be one of the most important factors in promoting fruit body maturation, and nitrogen metabolism and mTOR signaling pathway were associated with this process. In addition, 30 genes of interest were analyzed by quantitative real-time PCR to verify their expression profiles at the four developmental stages. This study advances our understanding of the molecular mechanism of fruiting body development in H. marmoreus by identifying a wealth of new genes that may play important roles in mushroom morphogenesis.

Equivalent salt deposit density (ESDD) and non-soluble deposit density (NSDD) measurements are a basic requirement of power systems. In order to predict the site pollution severity (SPS) of insulators, a new method based on random forests (RFs) is proposed. Using mutual information (MI) theory and RFs, the weights of factors related to the SPS of insulators are analyzed. The samples of contaminated insulators are extracted from the transmission lines of high voltage alternating current (HVAC) and high voltage direct current transmission (HVDC). The regression models of RFs and support vector machines (SVM) are constructed and compared, which helps to support the lack of information in predicting NSDD in previous works. The results are as follows: according to the mean decrease accuracy (MDA), mean decrease Gini, (MDG), and MI, the types of the insulators (including surface area, surface orientation, and total length) as well as the hydrophobicity are the main factors affecting both ESDD and NSDD. Compared with NSDD, the electrical parameters have a significant effect on ESDD. For the influence factors of ESDD, the weights of the insulator type, hydrophobicity, and meteorological factors are 52.94%, 6.35%, and 21.88%, respectively. For the influence factors of NSDD, the weights of the insulator type, hydrophobicity, and meteorological factors are 55.37%, 11.04%, and 14.26%, respectively. The influence voltage level (vl), voltage type (vt), polarity/phases (pp) exerted on ESDD are 1.5 times, 3 times, and 4.5 times of NSDD, respectively. The influence that distance from the coastline (d), wind velocity (wv), and rainfall (rf) exert on NSDD are 1.5 times, 2 times, and 2.5 times that of ESDD, respectively. Compared with the natural contamination test and the SVM regression model, the RFs regression model can effectively predict the contamination degree of insulators, and the relative error of the predicted ESDD and NSDD is 8.31% and 9.62%, respectively.

Ganoderma lucidum is a mushroom with traditional medicinal properties that has been widely used in China and other countries in Eastern Asia. Ganoderic acids (GA) produced by G. lucidum exhibit important pharmacological activities. Previous studies have demonstrated that methyl jasmonate (MeJA) is a potent inducer of GA biosynthesis and the expression of genes involved in the GA biosynthesis pathway in G. lucidum. To further explore the mechanism of GA biosynthesis, cDNA-Amplified Fragment Length Polymorphism (cDNA-AFLP) was used to identify genes that are differentially expressed in response to MeJA. Using 64 primer combinations, over 3910 transcriptionally derived fragments (TDFs) were obtained. Reliable sequence data were obtained for 390 of 458 selected TDFs. Ninety of these TDFs were annotated with known functions through BLASTX searching the GenBank database, and 12 annotated TDFs were assigned into secondary metabolic pathways by searching the KEGGPATHWAY database. Twenty-five TDFs were selected for qRT-PCR analysis to confirm the expression patterns observed with cDNA-AFLP. The qRT-PCR results were consistent with the altered patterns of gene expression revealed by the cDNA-AFLP technique. Additionally, the transcript levels of 10 genes were measured at the mycelium, primordia, and fruiting body developmental stages of G. lucidum. The greatest expression levels were reached during primordia for all of the genes except cytochrome b2 reached its highest expression level in the mycelium stage. This study not only identifies new candidate genes involved in the regulation of GA biosynthesis but also provides further insight into MeJA-induced gene expression and secondary metabolic response in G. lucidum.

Ganoderma lucidum is one of the most important medicinal mushrooms; however, molecular genetics research on this species has been limited due to a lack of reliable reverse genetic tools. In this study, the endogenous orotidine 5'-monophosphate decarboxylase gene (URA3) was cloned as a silencing reporter, and four gene-silencing methods using hairpin, sense, antisense, and dual promoter constructs, were introduced into G. lucidum through a simple electroporation procedure. A comparison and evaluation of silencing efficiency demonstrated that all of the four methods differentially suppressed the expression of URA3. Our data unequivocally indicate that the dual promoter silencing vector yields the highest rate of URA3 silencing compared with other vectors (up to 81.9%). To highlight the advantages of the dual promoter system, we constructed a co-silencing system based on the dual promoter method and succeeded in co-silencing URA3 and laccase in G. lucidum. The reduction of the mRNA levels of the two genes were correlated. Thus, the screening efficiency for RNAi knockdown of multiple genes may be improved by the co-silencing of an endogenous reporter gene. The molecular tools developed in this study should facilitate the isolation of genes and the characterization of the functions of multiple genes in this pharmaceutically important species, and these tools should be highly useful for the study of other basidiomycetes.

We have performed the temperature dependence of resistivity ρ(T) and thermoelectric power S(T) by a series of doping in layered cobaltites Bi2Sr2Co2Oy. For all samples, a metallic ρ(T) behavior and a large temperature-independent S is observed at higher temperatures, while we found a upturning ρ(T) but without corresponding variation of S(T) at lower temperatures. The present results strongly demonstrate the contribution of narrow band. Moreover, the doping could effectively modulate the thermoelectric performance. Especially for Bi2Sr1.9Ca0.1Co2Oy, it may provide an excellent platform to be a promising candidate of thermoelectric materials. [ABSTRACT FROM AUTHOR]

We have performed the temperature dependence of resistivity ρ(T) and thermoelectric power S(T) by a series of doping in layered cobaltites Bi2Sr2Co2Oy. For all samples, a metallic ρ(T) behavior and a large temperature-independent S is observed at higher temperatures, while we found a upturning ρ(T) but without corresponding variation of S(T) at lower temperatures. The present results strongly demonstrate the contribution of narrow band. Moreover, the doping could effectively modulate the thermoelectric performance. Especially for Bi2Sr1.9Ca0.1Co2Oy, it may provide an excellent platform to be a promising candidate of thermoelectric materials. [ABSTRACT FROM AUTHOR]

The structure, magnetization M, resistivity ?, thermoelectric power S, and thermal conductivity ? in La0.9Te0.1Mn1-xCoxO3 (0 ? x ? 1) have been investigated systematically. The samples with x = 0 and x = 1 have a rhombohedral lattice with space group R-3C, while the samples with x = 0.25, 0.50, and 0.75 have an orthorhombic lattice with space group Pbnm. The samples of 0 ? x ? 0.75 undergo the paramagnetic-ferromagnetic (PM-FM) phase transition. Based on the temperature dependence of susceptibility, a combination of the high-spin (HS) state for Co2+ and the low-spin (LS) state for Co3+ can be determined. The metal-insulator transitions (MIT) observed for x = 0 sample are completely suppressed with Co-doping, and ?(T) displays semiconducting behavior within the measured temperature region for x > 0 samples. As x ? 0.25, the huge magnitude of Seebeck coefficient at low temperatures is observed, which is suggested to originate from the spin-state transition of Co3+ ions from intermediate-spin (IS) state or (HS) state to (LS) state and the configurational entropy of charge carriers enhanced by their spin and orbital degeneracy between Co2+ and Co3+ sites. Particularly, S(T) of x = 0.50 and 0.75 samples appears an anomalous peak, which is suggested to be related to the contribution of phonon drag. Similar to M(T) and ?(T), all results of S(T) are discussed according to the variations of the structure parameters and magnetic exchange interaction caused by Co-doping. In addition, based on the analysis of the temperature dependence of S(T) and ?(T), the transport mechanism can be determined in the different temperature region. As to thermal conduction ?(T), the changes of ? with Co-doping is suggested to come from the combined effect due to the suppression of local Mn3+O6 Jahn-Teller (JT) lattice distortion because of the substitution of non JT Co3+ ions with LS and HS states for JT Mn3+ ions, which results in the increase of ?, and the introduction of the disorder due to Co-doping, which contributes to the decrease of ?. [ABSTRACT FROM AUTHOR]

Abstract: Cr-doped manganites Sr0.9Ce0.1Mn1−y Cr y O3 (y=0, 0.05, and 0.10) have been systematically investigated by X-ray, magnetic, transport, and elastic properties measurements. For parent compound Sr0.9Ce0.1MnO3, it undergoes a metal–insulator (M–I) transition at 318K, which is suggested to originate from a first-order structural transition accompanied by Jahn–Teller (JT) transition. With increasing Cr doping content, the JT transition temperature decreases. The Cr doping suppresses the antiferromagnetic (AFM) state and makes the system spin-glass (SG) behavior at low temperatures. In the vicinity of JT transition temperatures, the softening of Young''s modulus originating from the coupling of the orbital (quadrupolar) moment of the eg orbital of Mn3+ ion to the elastic strain has been observed. The anomalous Young''s modulus properties imply the electron–phonon coupling due to the JT effect may play an important role in the system. [Copyright &y& Elsevier]

Abstract: Electron-doped manganite Sr0.8Ce0.2MnO3 has been systematically investigated by X-ray diffraction, electronic transport, magnetic, internal friction, and Young''s modulus experiments. The X-ray diffraction result indicates that the compound remains tetragonal (I4/mcm) structure at room temperature. Due to the strong Jahn–Teller (JT) distortion, the ground state is antiferromagnetic (AFM) insulator. Below 20 K, a spin-glass (SG) state dominates at low temperatures. In the paramagnetic (PM) region, an internal friction peak at around 250 K, which is characteristic of relaxation, has been observed. Under applied magnetic field, the internal friction peak moves to higher temperature, which is suggested to originate from the formation of ferromagnetic (FM) clusters in PM region. In addition, the softening of Young''s modulus in the vicinity of AFM transition temperature is interpreted in terms of the strong electron–phonon interaction. [Copyright &y& Elsevier]

Abstract: The samples with the Mn3+/Mn4+ ratio fixed at 2:1 La(2+x)/3Sr(1−x)/3Mn1−x Cr x O3 (0≤x≤0.20) have been prepared. The magnetic, electrical transport, and magnetoresistance properties have been investigated. Remarkable transport and colossal magnetoresistance (CMR) effect, as well as cluster glass (CG) behaviors have been clearly observed in the samples studied. It was found that the Curie temperature T c and insulator−metal transition temperature T p1 are strongly affected by Cr substitution. The experiment observations are discussed by taking into account the variety of tolerance factors t; the effects of A-site radius 〈r A〉 and the A-site mismatch effect (σ 2). [Copyright &y& Elsevier]

The transition-metal dichalcogenides provided a good platform for the investigation of superconductivity and charge-density-wave (CDW) order. A series of high quality 6R-TaS2-xSex (0≤x≤1.6) single crystals were fabricated by the chemical-vapor-transport method and systematically investigated. The CDW becomes more stable with more S being replaced by Se, which causes expansion of the lattice, and produces a negative chemical pressure in the system. The x dependence of the onset of superconductivity (Tconset) shows a dome-like shape with a maximum of Tconset=2.7K at x=0.8. The magnetic susceptibility (4πχ) of x=0.8 under the hydrostatic pressure P=1.0 GPa was also measured, which showed a small increase of Tc and superconducting volume fraction. A pronounced peak effect was observed in the isothermal hysteresis with magnetic field (H) parallel to c-axis, which may arise from the quenching inhomogeneity and/or the stacking disorder. Finally, the evolution of the electronic states tuned by Se-doping was summarized in the phase diagram. [ABSTRACT FROM AUTHOR]

Abstract: The effect of K doping on structural, electronic transport, magnetic and specific heat properties in 4d perovskites Ba1− x K x MoO3 (0≤ x ≤0.2) has been investigated. Partial substitution of K+ ions for Ba2+ ions does not change the space group, but decreases the lattice parameter a monotonously. All samples exhibit metallic behavior in the whole measured temperature range. The K doping does not change the Pauli-paramagnetic behavior in high temperature region, but a weak ferromagnetic (FM) transition is induced at about 50K, which can be related to the deficiency of Mo. With K-doping content increasing, the resistivity increases, while the magnetic susceptibility and electronic specific heat coefficient decrease. The results are discussed according to the electron localization due to the disorder effect induced by dopants and the decrease in the density of state (DOS) at Fermi surface. [Copyright &y& Elsevier]

Abstract: Sr2FeMoO6 samples with different grain sizes were prepared by the sol–gel method. X-ray diffraction (XRD) patterns and field-emission scanning electron microscopy (FE-SEM) of the Sr2FeMoO6 samples show that the samples are in the nanometer range. The average grain sizes for these samples are 34.5, 39.7 and 44.3 nm, increasing with the sintering temperature. The transport measurements show that the Sr2FeMoO6 samples behave like semiconductors at low temperatures, dominated by the carrier scattering at the grain boundaries (GBs). And the resistivities of the samples are 1.6, 1.2 and 0.5 mΩ cm at 10 K, respectively, increasing with decreasing grain size. The temperature dependences of the magnetization and resistance clearly demonstrate the coexistence of ferromagnetic metal and antiferromagnetic (or paramagnetic) insulator, which is believed to induce a metal–insulator transition at the Curie temperature . [Copyright &y& Elsevier]

Abstract: The structure, resistivity, thermopower, and magnetization of the sample La0.9Te0.1MnO3 were investigated. The sample with a rhombohedral structure (R3¯C) undergoes the paramagnetic–ferromagnetic (PM–FM) transition accompanied by an insulator–metal (I–M) transition. Above the I–M transition temperature, a significant difference between the resistivity activation energy (E ρ =128.3 meV) and the thermopower activation energy (E S =14.7 meV), a characteristic of small polarons, is observed. In the PM region, the inverse magnetic susceptibility, 1/ χ m, is well described by the Curie–Weiss law indicating the absence of the short-range magnetic correlations, which further confirm that the conductivity above the I–M transition temperature for La0.9Te0.1MnO3 is indeed dominated by hopping of the lattice ‘small-polaron’ rather than hopping of the magnetic ‘small-polaron’. [Copyright &y& Elsevier]

Abstract: The structural and magnetic properties of the series compounds with nominal composition AlC x Ni3 (x=0, 0.025, 0.05, 0.075, 0.1, 0.2) have been investigated. All samples share the same space group Pm3m, while the lattice parameter a is found to increase monotonously with x. Both the Curie temperature T C and the spontaneous magnetic moment per Ni atom at 5K, μ Ni, decrease with increasing x. As x>0.05, the long-range ferromagnetic order disappears and the samples become exchange-enhanced Pauli paramagnets. It may be attributed to the reduction of the density of states (DOS) at the Fermi level, N(E F), due to the increasing Ni 3d–C 2p hybridization. [Copyright &y& Elsevier]

Abstract: The magnetism and transport properties of the samples LaMn1−x Ti x O3 (0≤x≤0.2) were investigated. All samples show a rhombohedral structure () at room temperature. The sample with x=0 undergoes the paramagnetic–ferromagnetic (PM–FM) transition accompanied by an insulator–metal (I–M) transition due to the oxygen excess. The doped samples show ferromagnetism and cluster behavior at low temperatures. Though no I–M transition associated with the PM–FM transition appears, the magnetoresistance (MR) effect was observed especially at low temperatures under the applied fields of 0.5T. Due to the fact that the oxygen content in the Ti-doped samples is nearly stochiometry (3.01) and the Hall resistivity at room temperature is negative, the ferromagnetism in LaMn1−x Ti x O3 (0.05≤x≤0.2) is believed to be consistent with the Mn2+–O–Mn3+ double exchange (DE) mechanism. These results suggest that DE can be obtained by direct Mn-site doping. [Copyright &y& Elsevier]

Background: With ventilatory support, boys with Duchenne Muscular Dystrophy (DMD) now live longer. The emerging adulthood offers unanticipated opportunities for identity exploration. Existing literature has raised issues around transitions and implicit obligations within structural and sociological domains; intrinsic challenges are posed, while concurrently engendering possibilities in an uncertain future., Objective: Reveal lived experience and meaning making among men with advanced DMD living outside the western context., Methods: Secondary data, essentially transcripts of semi-structured interviews with five young men with DMD, age ranging from 23 to 37 years, conducted as part of a larger study were analysed iteratively in depth. Given their underlying vulnerability associated with significant physical dependencies, all respondents were receiving palliative care from the local hospice, and lived with family caregivers at home., Results: Three themes encapsulated the essence of their lifeworld at this juncture. Each shared poignant stories of having survived adverse circumstances in the past, learning to live with themselves in the current state of disabilities and disconnection with peers. Yet, moments of yearning surface, to make new friends and find gainful employment like everyone else. Ambivalence notwithstanding, they navigated societal marginalization through digital media, or found meaning in family bonding and existential dimensions. Faced with uncertainty, most embraced the status quo in silent resignation, to minimise disappointment or as pragmatic responses to enduring systemic and personal barriers., Conclusions: Study findings expounded challenges men with advanced DMD grappled that ultimately shaped self-identity. Healthcare professionals could support this group of precarious survivors even better through individualised person-centred care., Competing Interests: Declaration of competing interest The corresponding author and co-authors do not have any conflict of interest (financial or otherwise) in relation to this manuscript to declare. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Involvement of authors in the research study., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: To date, there are no randomized, double-blinded clinical trials comparing catheter ablation to DC cardioversion (DCCV) with medical therapy in patients with persistent atrial fibrillation (PersAF). Conducting a large-scale trial to address this question presents considerable challenges, including recruitment, blinding, and implementation. We conducted a pilot study to evaluate the feasibility of conducting a definitive placebo-controlled trial., Methods: This prospective trial was carried out at Barts Heart Centre, United Kingdom, employing a randomized, double-blinded, placebo-controlled design. Twenty patients with PersAF (duration <2 years) were recruited, representing 10% of the proposed larger trial as determined by a power calculation. The patients were randomized in a 1:1 ratio to receive either PVI ± DCCV (PVI group) or DCCV + Placebo (DCCV group). The primary endpoint of this feasibility study was to evaluate patient blinding. Patients remained unaware of their treatment allocation until end of study., Results: During the study, 35% of patients experienced recurrence of PersAF prior to completion of 12 months follow-up. Blinding was successfully maintained amongst both patients and medical staff. The DCCV group had a trend to higher recurrence and repeat procedure rate compared to the PVI group (recurrence of PersAF 60% vs 30%; p = .07 and repeat procedure 70% vs 40%; p = .4). The quality of life experienced by individuals in the PVI group showed improvement, as evidenced by enhanced scores on the AF specific questionnaire (AF PROMS) (3 [±4] vs 21 [±8]) and SF-12 mental-component raw score (51.4 [±7] vs 43.24 [±15]) in patients who maintained sinus rhythm at 12 months., Conclusion: This feasibility study establishes the potential for conducting a blinded, placebo-controlled trial to evaluate the efficacy of PVI versus DCCV in patients with PersAF., Competing Interests: Disclosures Professor Schilling has received speaker and travel grants from Biosense Webster and research grants from Biosense Webster. Dr. Finlay has received research support from Abbott and Chief Medical Officer, founder and shareholder of Echopoint Medical Ltd. Other authors: No disclosures., (Copyright © 2023. Published by Elsevier Inc.)

Na doping strategy provides an effective avenue to upgrade the thermoelectric performance of PbTe-based materials by optimizing electrical properties. However, the limited solubility of Na inherently restricts the efficiency of doping, resulting in a relatively low average ZT , which poses challenges for the development and application of subsequent devices. Herein, to address this issue, the introduced spontaneous Pb vacancies and additional Mn doping synergistically promote Na solubility with a further modified valence band structure. Furthermore, the induced massive point defects and multiscale microstructure greatly strengthen the scattering of phonons over a wide frequency range, leading to a remarkable ultralow lattice thermal conductivity of ∼0.42 W m -1 K -1 . As a result, benefiting from the significantly enhanced Seebeck coefficient and superior thermal transports, a high peak ZT of ∼2.1 at 773 K and an excellent average ZT of ∼1.4 between 303 and 823 K are simultaneously achieved in Pb 0.93 Na 0.04 Mn 0.02 Te. This work proposes a simple and constructive method to obtain high-performance PbTe-based materials and is promising for the development of thermoelectric power generation devices.

The primary objective of this study is to investigate and develop a rapid and effective method for the immobilization of Sr in the event of a nuclear leakage incident. Coal gangue, an underutilized form of solid waste from the coal industry, can be used as a raw material for curing Sr due to its high content of silica-alumina oxides. In the present study, Sr was successfully solidified in cancrinite synthesized using a hydrothermal method with coal gangue as raw material. A stable cancrinite phase was formed at a relative alkali concentration of more than 6 M. When the Sr/Al(Si) ratio was <1/6, cancrinite was the only stable phase that varied with the hydrothermal temperature and time. When the Sr/Al(Si) ratio increased to 1/2, the cancrinite phase completely disappeared, and a new strontium feldspar phase (SrAl 2 Si 2 O 8 ) appeared. PCT leaching experiments showed that when Sr/Al(Si) < 1/6, the Sr leaching rate of Sr-cancrinite samples obtained by hydrothermal synthesis at 180 °C for 24 h was very low.