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This research explores the effects of wear on a 6063 aluminum alloy matrix combined with silicon carbide (SiC) and tungsten disulfide (WS2) particulates. Dry friction wear tests were conducted on three materials: pure 6063 aluminum alloy, a composite with 4 wt% SiC and 4 wt% WS2 reinforcement, and another composite with 6 wt% SiC and 4 wt% WS2 reinforcement. These materials were tested against AISI410 stainless steel discs under varying loads (10N, 20N, and 30N) and sliding rates (0.5, 1.0, and 1.5 ms−1) following a Taguchi L27 orthogonal experimental plan. Main effect graphs (S/N ratios) and ANOVA analysis were utilized to determine optimal parameter combinations, and confirmation tests were carried out to validate the Taguchi results. Scanning electron microscope (SEM) images of wear areas showed that incorporating SiC and WS2 significantly enhanced the wear resistance of the aluminum alloy. This indicates that incorporating SiC and WS2 reinforcement has the potential to enhance the wear resistance of aluminum alloys, making them suitable for applications such as piston rings in internal combustion engines, which is in line with the requirements of engine performance. Furthermore, potentiodynamic polarization studies evaluated the corrosion resistance of the Metal Matrix Composites AA6063 in 3.5% NaCl. Results indicated that the AA6063 + 6 wt% SiC + 4 wt% WS2 composite exhibited superior corrosion resistance compared to AA6063 alone.

Allometric equations are often used to estimate plant biomass allocation to different tissue types from easier-to-measure quantities. Biomass allocation, and thus allometric equations, often differs by species and sometimes varies with nutrient availability. We measured biomass components for five nitrogen-fixing tree species (Robinia pseudoacacia, Gliricidia sepium, Casuarina equisetifolia, Acacia koa, Morella faya) and three non-fixing tree species (Betula nigra, Psidium cattleianum, Dodonaea viscosa) grown in field sites in New York and Hawaii for 4-5 years and subjected to four fertilization treatments. We measured total aboveground, foliar, main stem, secondary stem, and twig biomass in all species, and belowground biomass in Robinia pseudoacacia and Betula nigra, along with basal diameter, height, and canopy dimensions. The individuals spanned a wide size range (

We have investigated the electrical transport properties of nanodevices fabricated from exfoliated flakes of two-dimensional metallic ferromagnets Fe3GeTe2 (FGT) and Fe5Ge2Te2 (FG2T) down to below three layers in thickness. The per-layer anomalous Hall conductivity even in thick FGT and FG2T devices is found to be much smaller than ∼ e 2 h , the approximate value calculated for thick undoped crystals. Moreover, we obtain a power-law scaling relation between the per-layer anomalous Hall and per-layer longitudinal conductivities with an exponent close to 1.6, which agrees with the universal value for poor ferromagnetic conductors. Both FGT and FG2T devices show clear layer-dependent Curie temperatures and layer-dependent perpendicular magnetic anisotropy, with FG2T dominating the former and FGT dominating the latter for all thicknesses. Despite their declining trend as the device thickness decreases, both Curie temperature and magnetic anisotropy retain a significant fraction of their bulk values (>60% and >80% of the bulk values, respectively, even in the thinnest FG2T device), indicating attractive potential for practical applications. [ABSTRACT FROM AUTHOR]

We have investigated the electrical transport properties of nanodevices fabricated from exfoliated flakes of two-dimensional metallic ferromagnets Fe3GeTe2 (FGT) and Fe5Ge2Te2 (FG2T) down to below three layers in thickness. The per-layer anomalous Hall conductivity even in thick FGT and FG2T devices is found to be much smaller than ∼ e 2 h , the approximate value calculated for thick undoped crystals. Moreover, we obtain a power-law scaling relation between the per-layer anomalous Hall and per-layer longitudinal conductivities with an exponent close to 1.6, which agrees with the universal value for poor ferromagnetic conductors. Both FGT and FG2T devices show clear layer-dependent Curie temperatures and layer-dependent perpendicular magnetic anisotropy, with FG2T dominating the former and FGT dominating the latter for all thicknesses. Despite their declining trend as the device thickness decreases, both Curie temperature and magnetic anisotropy retain a significant fraction of their bulk values (>60% and >80% of the bulk values, respectively, even in the thinnest FG2T device), indicating attractive potential for practical applications. [ABSTRACT FROM AUTHOR]

Phosphorus (P) limits productivity in many ecosystems and has the potential to constrain the global carbon sink. The magnitude of these effects depends on how climate change and rising CO2 affect P cycling. Some effects are well established. First, P limitation often constrains CO2 fertilization, and rising CO2 often exacerbates P limitation. Second, P limitation and P constraints to CO2 fertilization are more common in warmer and wetter sites. Models that couple P cycling to vegetation generally capture these outcomes. However, due largely to differences between short-term and long-term dynamics, the patterns observed across climatic gradients do not necessarily indicate how climate change over years to decades will modify P limitation. These annual-to-decadal effects are not well understood. Furthermore, even for the well-understood patterns, much remains to be learned about the quantitative details, mechanisms, and drivers of variability. The interface between empirical and modeling work is particularly ripe for development. [ABSTRACT FROM AUTHOR]

Allometric equations are often used to estimate plant biomass allocation to different tissue types from easier-to-measure quantities. Biomass allocation, and thus allometric equations, often differs by species and sometimes varies with nutrient availability. We measured biomass components for five nitrogen-fixing tree species (Robinia pseudoacacia, Gliricidia sepium, Casuarina equisetifolia, Acacia koa, Morella faya) and three non-fixing tree species (Betula nigra, Psidium cattleianum, Dodonaea viscosa) grown in field sites in New York and Hawaii for 4–5 years and subjected to four fertilization treatments. We measured total aboveground, foliar, main stem, secondary stem, and twig biomass in all species, and belowground biomass in Robinia pseudoacacia and Betula nigra, along with basal diameter, height, and canopy dimensions. The individuals spanned a wide size range (<1–16 cm basal diameter; 0.24–8.8 m height). For each biomass component, aboveground biomass, belowground biomass, and total biomass, we determined the following four allometric equations: the most parsimonious (lowest AIC) overall, the most parsimonious without a fertilization effect, the most parsimonious without canopy dimensions, and an equation with basal diameter only. For some species, the most parsimonious overall equation included fertilization effects, but fertilization effects were inconsistent across fertilization treatments. We therefore concluded that fertilization does not clearly affect allometric relationships in these species, size classes, and growth conditions. Our best-fit allometric equations without fertilization effects had the following R2 values: 0.91–0.99 for aboveground biomass (the range is across species), 0.95 for belowground biomass, 0.80–0.96 for foliar biomass, 0.94–0.99 for main stem biomass, 0.77–0.98 for secondary stem biomass, and 0.88–0.99 for twig biomass. Our equations can be used to estimate overall biomass and biomass of tissue components for these size classes in these species, and our results indicate that soil fertility does not need to be considered when using allometric relationships for these size classes in these species. [ABSTRACT FROM AUTHOR]

This study examined the impact of a combination of hardened and tempered surface change technologies and AlCrN coating on the tribological characteristics of AISID2 steel. The duplex surface change, such as the combination of a heat treatment at 600°C for 1 hr and a PVD (sputtering), archives the superior wear resistance and mechanical properties. AlCrN coating has been implemented in AISID2 steel after a hardened and tempered treatment. This process was carried out as part of an appropriate thermal treatment cycle in accordance with ASM Vol.2. Subsequently, the AlCrN coating synthesised by PVD (sputtering) improves the adhesion between the coatings and the AISID2 steel. The wear properties according to ASTMG99 have been tested with a typical load of 10N, 20N and 30N for a sliding distance of 6000 m with a constant velocity of 1.256 ms−1 in wet conditions. Tests revealed that the AlCrN coating deposited on the hardened and tempered steel was more resistant to wear than the AlCrN coating applied to the unhardened steel. Therefore, it should be possible to implement the results of this study for forming operations with low COF and a low amount of resulting wear such as drawing and rolling in dies. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is a key nutrient required by all living organisms for growth and development, but is a limiting resource for many organisms. Organisms that feed on material with low N content, such as wood, might be particularly prone to N limitation. In this study, we investigated the degree to which the xylophagous larvae of the stag beetle Ceruchus piceus (Weber) use associations with N-fixing bacteria to acquire N. We paired acetylene reduction assays by cavity ring-down absorption spectroscopy (ARACAS) with 15N2 incubations to characterize rates of N fixation within C. piceus. Not only did we detect significant N fixation activity within C. piceus larvae, but we calculated a rate that was substantially higher than most previous reports for N fixation in insects. While taking these measurements, we discovered that N fixation within C. piceus can decline rapidly in a lab setting. Consequently, our results demonstrate that previous studies, which commonly keep insects in the lab for long periods of time prior to and during measurement, may have systematically under-reported rates of N fixation in insects. This suggests that within-insect N fixation may contribute more to insect nutrition and ecosystem-scale N budgets than previously thought. [ABSTRACT FROM AUTHOR]

Symbiotic nitrogen fixation (SNF) is a key ecological process whose impact depends on the strategy of SNF regulation—the degree to which rates of SNF change in response to limitation by N versus other resources. SNF that is obligate or exhibits incomplete downregulation can result in excess N fixation, whereas a facultative SNF strategy does not. We hypothesized that tree‐based SNF strategies differed by latitude (tropical vs. temperate) and symbiotic type (actinorhizal vs. rhizobial). Specifically, we expected tropical rhizobial symbioses to display strongly facultative SNF as an explanation of their success in low‐latitude forests. In this study we used 15N isotope dilution field experiments in New York, Oregon, and Hawaii to determine SNF strategies in six N‐fixing tree symbioses. Nitrogen fertilization with +10 and +15 g N m−2 year−1 for 4–5 years alleviated N limitation in all taxa, paving the way to determine SNF strategies. Contrary to our hypothesis, all six of the symbioses we studied sustained SNF even at high N. Robinia pseudoacacia (temperate rhizobial) fixed 91% of its N (%Ndfa) in controls, compared to 64% and 59% in the +10 and +15 g N m−2 year−1 treatments. For Alnus rubra (temperate actinorhizal), %Ndfa was 95%, 70%, and 60%. For the tropical species, %Ndfa was 86%, 80%, and 82% for Gliricidia sepium (rhizobial); 79%, 69%, and 67% for Casuarina equisetifolia (actinorhizal); 91%, 42%, and 67% for Acacia koa (rhizobial); and 60%, 51%, and 19% for Morella faya (actinorhizal). Fertilization with phosphorus did not stimulate tree growth or SNF. These results suggest that the latitudinal abundance distribution of N‐fixing trees is not caused by a shift in SNF strategy. They also help explain the excess N in many forests where N fixers are common. [ABSTRACT FROM AUTHOR]

Light and soil nitrogen availability can be strong controls of plant nitrogen (N) fixation, but data on how understory N‐fixing plants respond to these drivers are limited despite their important role in ecosystem N cycling. Furthermore, ecosystem N cycling can be altered by the introduction of species with nutrient use patterns that differ from natives. We assessed how N fixation of two exotic, understory species responded to varying light and soil N environments.We sampled leaf tissue from Mimosa pudica L., Desmodium triflorum (L.) DC., and a nonfixing reference plant (Axonopus) growing in control and two N fertilization treatments under either N‐fixing or non‐N‐fixing trees, which may alter local soil nutrient cycling, across a range of light conditions. We measured N fixation with 15N isotope dilution, and ensured that N‐fixing neighbour trees were in fact fixing N. All understory plants were wild‐growing species not native to the study location.Desmodium and Mimosa acquired 82.6% and 71.6% of their nitrogen from fixation (%Ndfa) in the control, compared to 66.8% and 58.1% in the +10 g N m−2 year−1 treatment and 73.1% and 64.7% in the +15 g N m−2 year−1 treatment. These subtle %Ndfa differences across fertilization treatments were more apparent at low light availability and disappeared at high light availability. The amount of N fixed by neighbouring trees did not influence %Ndfa in the understory species.Synthesis. Our study shows some differences in N fixation across different nutrient environments at low light for two N‐fixing species, though the changes were small, and both species derived most of their N from fixation. These findings imply that introduced N‐fixing species could exacerbate ecosystem N enrichment, particularly under high soil N conditions. [ABSTRACT FROM AUTHOR]

Layered van der Waals (vdW) crystals with intrinsic magnetic properties such as high Curie temperature (TC) and large perpendicular magnetic anisotropy (PMA) are key to the development and application of spintronic devices. The ferromagnetic vdW metal Fe3−xGeTe2 (FGT) has gained prominence recently due to its high TC (220 K) and strong PMA. Herein, a new metallic vdW ferromagnet, Fe5−xGe2Te2 or FG2T, is introduced, which is successfully synthesized and fully characterized. FG2T is a metal that orders ferromagnetically with a very sharp transition at 250 K (bulk and single‐crystal thin flakes) and shows large PMA, as found by both experimental and computational studies. Novel heterostructure devices with near‐room‐temperature capabilities using FG2T as a spin injector are enabled by this work. [ABSTRACT FROM AUTHOR]

This study conducted to find out the electronic information/resources access and seeking behavior of engineering college students in Vellore district. Objective- of the paper is to identify the availability of e-resources, awareness, usage level, level of satisfaction and barriers during access of the students. Methodology-a systematic questionnaire designed and distributed among the Engineering College library users. After data collection analysis of the study done. Findings - It is observed from the data analysis most of the UG Students are using Google as their search engine and they prefer DELNET also on the other hand PG students and faculty prefer all subscribed resources for their teaching and learning. There is a less awareness about the commercial resources among the students. Suggestions were given to improve the infrastructure and need orientation programme for all category of users. [ABSTRACT FROM AUTHOR]

Ultrasonic velocity (U), viscocity (η) and density (ρ) of L - ascorbic acid, dextrose and sucrose in aqueous guanidine hydrochloride (0.3 m) have been measured at 298.15 K. The derived acoustical parameters namely adiabatic compressibility (β), apparent molal compressibility (φK) apparent molal volume (φv) limiting apparent molal compressibility ((φ0K) limiting apparent molal volume (φ0v) and their constants (SK, SV) and viscosity Bcoefficient and hydration number (nH) have been computed from the experimental data. The variation of these parameters with respect to the molality of solutes have been explained on the basis of solute-solvent interaction and structure making tendency of the solutes in solvents. [ABSTRACT FROM AUTHOR]

Hemangiomas are common vascular tumors occurring in children. Though most of the lesions present in infants and young children with a typical appearance, it is important to understand that they all do not behave in the same way. Rather, they are a group of vascular lesions with different clinico-pathological subtypes, with their clinical behavior varying with the stage of the tumor as well. As such, they can and do have a varied clinical, imaging and pathological appearance according to the location of the tumor and also the stage at which the patient is seen. In this pictorial essay, the classification, pathogenesis, clinical appearance, natural history and imaging characteristics of hemangiomas are reviewed and illustrated. [ABSTRACT FROM AUTHOR]

Hemangiomas, although benign tumors, can when located in particular regions threaten vital structures or in certain clinical circumstances be associated with other abnormalities, carrying significant morbidity and mortality. We review these endangering hemangiomas. We also discuss briefly the treatment with emphasis on the recent use of propranolol. [ABSTRACT FROM AUTHOR]

Ultrasonic velocity (U), density (ρ) and viscosity (η) for the ternary liquid mixtures of water + propylene glycol + tetrahydrofuran, water + propylene glycol + dimethylformamide, water + propylene glycol + dimethylsulphoxide and water + propylene glycol + 1,4-dioxane have been measured as a function of the composition at 303, 308 and 313 K. The experimental data have been used to calculate some excess thermodynamical parameters such as excess viscosity (ηE), excess free volume ( [image omitted]), excess Gibb's free energy (ΔGE) and interaction parameter (d). The results are discussed and interpreted in terms of structural and specific interaction predominated by hydrogen bonding. [ABSTRACT FROM AUTHOR]

Rechargeable lithium-oxygen (Li-O 2 ) batteries are being considered as the next-generation energy storage systems due to their higher theoretical energy density. However, the practical application of Li-O 2 batteries is hindered by slow kinetics and the formation of side products during the oxygen reduction and evolution reactions on the cathode. These reactions lead to high overpotentials during charging and discharging. To address these challenges, we propose a simple ultrasonic method for synthesizing cobalt nanoclusters embedded in nitrogen-doped graphene nanosheets (GrZnCo) derived from metal-organic frameworks (MOFs). The resulting material, due to the retention of metallic cobalt structure, exhibits better electronic conductivity. Additionally, the GrZnCo catalyst shows vigorous catalytic activity, which can improve reaction kinetics and suppress side reactions, thus lowering the charging overpotential. We have investigated the impact of different catalyst compositions (GrZnCo x ; x  = 1, 3, 5) by varying the amounts of cobalt and zinc. The optimum catalyst, GrZnCo 3 , contains high cobalt-N active components, graphitic-N, pyridinic-N, pyrrolic-N, and abundant defect structures, which enhance the electrochemical performance. The defect-rich GrZnCo 3 catalyst enables Li-O 2 batteries to achieve a high discharge capacity of 13500 mAh·g -1 at 50 mA·g -1 and a remarkable long-term cycling performance of over 400 cycles at 100 mA·g -1 with a limited capacity of 500 mAh·g -1 . This work demonstrates an effective approach to fabricate cost-effective electrocatalysts for various energy storage systems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Neuroendocrine hyperplasia of infancy is a rare form of pediatric interstitial lung disease presenting with hypoxemia, tachypnea, retractions, and persistent pulmonary crackles in the first year of life. As these children frequently require supplemental oxygen therapy and demonstrate nighttime hypoxemia, there is a concern for an increased prevalence of sleep-disordered breathing in this population, including obstructive sleep apnea. As untreated sleep-disordered breathing is associated with adverse developmental outcomes for children, it is essential to promptly diagnose and treat. However, treatment of obstructive sleep apnea is often challenging in children. In this report, we describe a case of a child diagnosed with neuroendocrine hyperplasia of infancy at 12 months of age who was subsequently found to have severe obstructive sleep apnea that persisted despite adenotonsillectomy. As continuous positive airway pressure was not well tolerated, the patient was initiated on a high-flow nasal cannula at nighttime, which resulted in improvement of his sleep apnea and daytime functioning with better adherence to treatment. Our case illustrates the importance of screening for sleep-disordered breathing in patients with neuroendocrine hyperplasia of infancy, as well as the utility of a high-flow nasal cannula as a novel, effective treatment for pediatric obstructive sleep apnea., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Feller et al.)

Study Objectives: Recurrent/residual adenoid hypertrophy after adenotonsillectomy in children can result in obstructive sleep apnea (OSA). We aimed to assess the role of soft tissue neck X-ray (STN-XR) in evaluating recurrent/residual adenoid tissue hypertrophy., Methods: This was a single-center retrospective study that included children with sleep study-confirmed OSA and a known history of adenotonsillectomy who underwent STN-XR to evaluate for recurrent/residual adenoid tissue hypertrophy. STN-XR nasopharyngeal obliteration and baseline polysomnographic data were analyzed. Multiple linear regression was used to assess the independent relationship between the results of STN-XR and the total apnea-hypopnea index, while controlling for relevant characteristics., Results: The study included 160 participants with a median age of 10 years (quartile [Q] 1 = 7, Q3 = 12.25). More than half of the children were male (59.4%) and the median body mass index z -score was 2.11 (Q1 = 1.23, Q3 = 2.54). STN-XR was normal in 39.4%, and it showed mild, moderate, and complete nasopharyngeal obliteration in 20.6%, 32.5%, and 7.5% of the participants, respectively. Multiple regression analysis showed that moderate and complete nasopharyngeal obliteration was associated with an increase in the mean total apnea-hypopnea index by 109% ( P = .0002) and 185% ( P = .001), respectively, when compared with children without nasopharyngeal obliteration. However, mild nasopharyngeal obliteration, body mass index z -score, age, sex, and race were not significantly associated with an increase in the total apnea-hypopnea index., Conclusions: STN-XR was useful in assessing recurrent/residual adenoid tissue hypertrophy in children with OSA and a history of adenotonsillectomy. Moderate and complete nasopharyngeal obliteration were associated with significantly increased apnea-hypopnea index. Pediatric sleep physicians may consider STN-XR in the evaluation of children with OSA and previous history of adenotonsillectomy., Citation: Senthilvel E, Nguyen QL, Gunaratnam B, Feygin YB, Palani R, El-Kersh K. Role of neck radiography in assessing recurrent/residual adenoid hypertrophy in children with OSA and history of adenotonsillectomy: a sleep physician perspective. J Clin Sleep Med . 2023;19(6):1027-1033., (© 2023 American Academy of Sleep Medicine.)

Despite the expanding applications of dynamic nuclear polarization (DNP) to problems in biological and materials science, there remain unresolved questions concerning DNP mechanisms. In this paper, we investigate the Zeeman DNP frequency profiles obtained with trityl radicals, OX063 and its partially deuterated analog OX071, in two commonly used glassing matrices based on glycerol and dimethyl sulfoxide (DMSO). When microwave irradiation is applied in the neighborhood of the narrow EPR transition, we observe a dispersive shape in the 1 H Zeeman field and the effects are larger in DMSO than in glycerol. With the help of direct DNP observations on 13 C and 2 H nuclei, we investigate the origin of this dispersive field profile. In particular, we observe a weak nuclear Overhauser effect between 1 H and 13 C in the sample, which, when irradiating at the positive 1 H solid effect (SE) condition, results in a negative enhancement of 13 C spins. This observation is not consistent with thermal mixing (TM) being the mechanism responsible for the dispersive shape in the 1 H DNP Zeeman frequency profile. Instead, we propose a new mechanism, resonant mixing, involving mixing of nuclear and electron spin states in a simple two-spin system without invoking electron-electron dipolar interactions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Long-acting somatostatin analogues (SSAs) are the most commonly used drugs in the management of neuroendocrine tumours (NETs) because of their ability to control symptoms and prolong survival. SSA use is associated with changes in glucose metabolism. However, the impacts on glycaemic control and body mass index (BMI) caused by SSAs in NETs are largely unknown. In the present study, we evaluated the effects of SSA treatment on BMI and glycated haemoglobin (HbA1c) in our cohort of patients with NETs. We also assessed changes in glycaemic control and BMI before and after SSA treatment. In addition, we assessed the incidence of new diabetes or whether there was worsening of glycaemic control for patients with pre-existing diabetes. The study comprised a retrospective study of 279 patients with NETs who were treated with SSAs between January 2014 and January 2019. Glycaemic control was assessed by measuring changes in Hba1c. A number needed to harm analysis was used to look at new cases of diabetes within the study population. Treatment with SSAs was associated with a mean increase in HbA1c of 3.35 ± 6.30 mmol mol -1 despite a mean decrease in BMI of -1.04 ± 2.79 kg m -2 . There were 19 new cases of type 2 diabetes mellitus (T2DM) in the population of 209 with a number needed to harm of 12.5. Of the 34 patients with pre-existing T2DM, five had worsening of their mean HbA1c. Treatment with SSAs for NETs is associated with an increase in HbA1c, despite a reduction in BMI and, importantly, a risk of developing T2DM with a number needed to harm of 12.5. This project was registered with the National Health Service Clinical Audit and Registries. It has a CARMS number - 17666., (© 2021 British Society for Neuroendocrinology.)

This paper presents a simple strategy for manufacturing bifunctional electrocatalysts-graphene nanosheets (GNS) coated with an ultrafine NiCo-MOF as nanocomposites (denoted NiCo-MOF@GNS) having a N-doped defect-rich and abundant cavity structure through one-pool treatment of metal-organic frameworks (MOFs). The precursors included N-doped dodecahedron-like graphene nanosheets (GNS), in which the NiCo-MOF was encompassed within the inner cavities of the GNS (NiCo-MOF@GNS) at the end or middle portion of the tubular furnace with several graphene layers. Volatile imidazolate N x species were trapped by the NiCo-MOF nanosheets during the pyrolysis process, simultaneously inserting N atoms into the carbon matrix to achieve the defect-rich porous nanosheets and the abundantly porous cavity structure. With high durability, the as-prepared nanomaterials displayed simultaneously improved performance in the oxygen reduction reaction (ORR), the oxygen evolution reaction (OER), and photocatalysis. In particular, our material NiCo-MOF@GNS-700 exhibited excellent electrocatalytic activity, including a half-wave potential of 0.83 V ( E ORR, 1/2 ), a low operating voltage of 1.53 V ( E OER, 10 ) at 10 mA cm -2 , a potential difference (Δ E ) of 1.02 V between E OER, 10 and E ORR, 1/2 in 0.1 M KOH, and a low band gap of 2.61 eV. This remarkable behavior was due to the structure of the defect-rich porous carbon nanosheets and the synergistic impact of the NPs in the NiCo-MOF, the N-doped carbon, and NiCo-N x . Furthermore, the hollow structure enhanced the conductivity and stability. This useful archetypal template allows the construction of effective and stable bifunctional electrocatalysts, with potential for practical viability for energy conversion and storage., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Among van der Waals (vdW) layered ferromagnets, Fe 3 GeTe 2 (FGT) is an excellent candidate material to form FGT/heavy metal heterostructures for studying the effect of spin-orbit torques (SOT). Its metallicity, strong perpendicular magnetic anisotropy built in the single atomic layers, relatively high Curie temperature ( T c ∼ 225 K), and electrostatic gate tunability offer a tantalizing possibility of achieving the ultimate high SOT limit in monolayer all-vdW nanodevices. In this study, we fabricate heterostructures of FGT/Pt with 5 nm of Pt sputtered onto the atomically flat surface of ∼15-23 nm exfoliated FGT flakes. The spin current generated in Pt exerts a damping-like SOT on FGT magnetization. At ∼2.5 × 10 11 A/m 2 current density, SOT causes the FGT magnetization to switch, which is detected by the anomalous Hall effect of FGT. To quantify the SOT effect, we measure the second harmonic Hall responses as the applied magnetic field rotates the FGT magnetization in the plane. Our analysis shows that the SOT efficiency is comparable with that of the best heterostructures containing three-dimensional (3D) ferromagnetic metals and much larger than that of heterostructures containing 3D ferrimagnetic insulators. Such large efficiency is attributed to the atomically flat FGT/Pt interface, which demonstrates the great potential of exploiting vdW heterostructures for highly efficient spintronic nanodevices.

Two different boron layers, flat (graphene-like) and puckered (phosphorene-like), found in the crystal structure of Mo 2 B 4 show drastically different activities for hydrogen evolution, according to Gibbs free energy calculations of H-adsorption on Mo 2 B 4 . The graphene-like B layer is highly active, whereas the phosphorene-like B layer performs very poorly for hydrogen evolution. A new Sn-flux synthesis permits the rapid single-phase synthesis of Mo 2 B 4 , and electrochemical analyses show that it is one of the best hydrogen evolution reaction active bulk materials with good long-term cycle stability under acidic conditions. Mo 2 B 4 compensates its smaller density of active sites if compared with highly active bulk MoB 2 (which contains only the more active graphene-like boron layers) by a 5-times increase of its surface area.

Over the past decade, we have witnessed significant advances in knowledge of the biology and treatment of chronic myeloid leukaemia (CML). The development of molecular-targeted therapy with tyrosine kinase inhibitors (TKIs) has fundamentally changed the outcome of this disease. Treatment with TKIs is now the standard of care in patients with CML and has dramatically improved long-term survival in the majority of patients. Patients who achieve major molecular response (MMR) after 2 years of treatment with imatinib have survival rates comparable to those of the general population. The success of TKIs has led to durable molecular response and possibility of normal life expectancies, such that it is now timely to address quality of life aspects such as fertility, pregnancy and family planning. Pregnancy in CML presents specific management and therapeutic challenges for the patient and the physician. Despite the recent treatment advances, we still have limited data on the safety of TKIs in pregnancy and its effect on fertility. However, there is a cause for concern and heightened awareness following the occurrence of a constellation of rare congenital malformations and spontaneous abortions in association with imatinib therapy. When a patient becomes pregnant whilst receiving TKI therapy, the difficulty lies in balancing the risk to the foetus of continuing therapy versus the risk to the patient of treatment interruption and potentially losing optimal disease response. All couples should be counselled on the risks associated with pregnancy whilst receiving TKI therapy. This is an essential aspect in patient care and frequently not emphasized enough by physicians. At the time of diagnosis, fertility preservation should be discussed with both male and female patients of childbearing potential. They should be made aware of fertility options which are available such as semen cryopreservation, ovarian or oocyte retrieval and storage and embryo cryopreservation in view of the potential detrimental effect of TKIs on fertility and gonadal function. The recommendation given to patients planning pregnancy differs according to their disease response to TKI therapy, which is the most important prognostic factor in CML.

Various diseases in the pediatric age group can present as an intrathoracic rounded opacity on a chest radiograph. The purpose of this pictorial essay is to emphasize the imaging appearance of round pneumonia, an entity that occurs especially in the pediatric population. Additional pathologies with similar chest radiographic appearances are also presented. The diagnosis of round pneumonia should be made in children who have the typical clinical presentation along with chest radiographs demonstrating the characteristic findings.