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Recently, 27 new half-Heusler compounds XYZ (X=Co, Rh, Fe, Ru, Ni; Y=Sc, Ti, V; Z=P, As, Sb, Si, Ge, Sn, Al, Ga, In) with 18 valence electrons are proposed and their bandgaps span a wide range of 0.10-1.39 eV, which have a great potential of applications in varied areas. Note that the bandgaps are predicted on the gradient-corrected Perdew-Burke-Ernzerhof functional, which underestimates the magnitude of bandgap. To obtain the accurate bandgaps, we recalculate them based on the Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional. Our results show that the nonlocal correction from the HSE06 functional mainly acts on the two lowest conduction bands. The variation in energy separation between these two bands dominates the relative increment of bandgap. More importantly, the band ordering is distinguished in the presence of HSE06 functional, where the dz2 orbital exhibits. When the lattice constant varies, such a band ordering can be inverted, similar to the case of topological insulators. In addition, we find an abnormal behavior of the bandgap related to the Pauling electronegativity difference between the X- and Z-sites, which arises from the delocalization of charge on the Y-site. We expect that our work can provide guidance to the study of bandgap based on the hybrid density functional theory in the half-Heusler semiconductors. [ABSTRACT FROM AUTHOR]

When a laser pulse excites a ferromagnet, its spin undergoes a dramatic change. The initial demagnetization process is very fast. Experimentally, it is found that the demagnetization time is related to the spin moment in the sample. In this study, we employ the first-principles method to directly simulate such a process. We use the fixed spin moment method to change the spin moment in ferromagnetic nickel, and then we employ the Liouville equation to couple the laser pulse to the system. We find that in general the dependence of demagnetization time on the spin moment is nonlinear: It decreases with the spin moment up to a point, after which an increase with the spin moment is observed, followed by a second decrease. To understand this, we employ an extended Heisenberg model, which includes both the exchange interaction and spin-orbit coupling. The model directly links the demagnetization rate to the spin moment itself and demonstrates analytically that the spin relaxes more slowly with a small spin moment. A future experimental test of our predictions is needed. [ABSTRACT FROM AUTHOR]

Based on first-principles calculations, we present a quantum confinement mechanism for the band gaps of blue phosphorene nanoribbons (BPNRs) as a function of their widths. The BPNRs considered have either armchair or zigzag shaped edges on both sides with hydrogen saturation. Both the two types of nanoribbons are shown to be indirect semiconductors. An enhanced energy gap of around 1 eV can be realized when the ribbon's width decreases to ∼10Å . The underlying physics is ascribed to the quantum confinement effect. More importantly, the parameters to describe quantum confinement are obtained by fitting the calculated band gaps with respect to their widths. The results show that the quantum confinement in armchair nanoribbons is stronger than that in zigzag ones. This study provides an efficient approach to tune the band gap in BPNRs. [ABSTRACT FROM AUTHOR]

Understanding the mechanism of ferromagnetism in hexagonal boron nitride nanosheets, which possess only s and p electrons in comparison with normal ferromagnets based on localized d or f electrons, is a current challenge. In this work, we report an experimental finding that the ferromagnetic coupling is an intrinsic property of hexagonal boron nitride nanosheets, which has never been reported before. Moreover, we further confirm it from ab initio calculations. We show that the measured ferromagnetism should be attributed to the localized π states at edges, where the electronelectron interaction plays the role in this ferromagnetic ordering. More importantly, we demonstrate such edge-induced ferromagnetism causes a high Curie temperature well above room temperature. Our systematical work, including experimental measurements and theoretical confirmation, proves that such unusual room temperature ferromagnetism in hexagonal boron nitride nanosheets is edge-dependent, similar to widely reported graphene-based materials. It is believed that this work will open new perspectives for hexagonal boron nitride spintronic devices. [ABSTRACT FROM AUTHOR]

We investigate the electronic properties of bilayer MoS2 exposed to an external electric field by using first-principles calculations. It is found that a larger interlayer distance, referring to that by standard density functional theory (DFT) with respect to that by DFT with empirical dispersion corrections, makes indirect-direct band gap transition possible by electric control. We show that external electric field effectively manipulates the valence band contrast between the K- and Γ-valleys by forming built-in electric dipole fields, which realizes an indirect-direct transition before a semiconductor-metal transition happens. Our results provide a novel efficient access to tune the electronic properties of two-dimensional layered materials. [ABSTRACT FROM AUTHOR]

Aim: We compared the vaccine effectiveness of monovalent and combination hepatitis B vaccine regimens in infants born to chronic hepatitis B carrier mothers.Methods: An observational cohort of neonates was recruited over 78 months from two public hospital maternity units in Singapore. We enrolled term infants, born to chronic hepatitis B surface antigen-positive mothers regardless of their hepatitis Be antigen status, who completed the hepatitis B virus (HBV) vaccination programme in Singapore. Infants born to mothers on antiviral therapy, or with concurrent hepatitis C or human immunodeficiency virus infection were excluded. All infants received hepatitis B immunoglobulin at birth. One group received three doses of monovalent hepatitis B vaccine (0, 1, 6 months) (regimen A). The other group received two doses of monovalent vaccine, followed by one dose combination vaccine DTaP-IPV-Hib-HBV (0, 1, 6 months) (regimen B). Vaccine effectiveness was determined by immunoprophylaxis failure leading to HBV vertical transmission. Immunogenicity was assessed by hepatitis B surface antibody (anti-HBs) levels at 9 months of age.Results: Total of 177 term neonates received regimen A and 115 received regimen B. Immunoprophylaxis failure rate was low, 2.3 and 2.6% (P = 1.00) in regimen A and B, respectively. Mean anti-HBs titres were similar at 643 ± 374 and 561 ± 396 IU/L (P = 0.08) for regimen A and B, respectively.Conclusion: Hepatitis B vaccine regimens using monovalent or combination vaccine for the third dose showed similarly high vaccine effectiveness and low immunoprophylaxis failure rate in term infants born to chronic hepatitis B carrier mothers. [ABSTRACT FROM AUTHOR]

Abstract: Improving the thermostability of the luciferase from firefly (Photinus pyralis) needs to be solved to broaden its industrial applications. In this paper, molecular dynamic (MD) simulations were used to identify 4 amino acid substitutions (P183V, E325K, Q338V, and E354K) which might have a significant influence on the thermostability of luciferase. Root-mean-square deviation values were calculated to further evaluate the effect of these mutations on thermostability of the enzyme and demonstrated that the thermostability of the corresponding protein variants was in the order E354K > E325K > WT > P183V > Q338V. Following the MD simulation, the enzyme variants were expressed in a recombinant host, and the results showed that the t1/2, T50, and Tm of mutant E354K were increased 2.32-fold, and 4.5 and 3.3°C more compared with the wild type, respectively. MD simulations, as well as circular dichroism and fluorescence spectroscopy were further applied to elucidate the conformational differences between the wild-type and E354K luciferases. The results indicated that a possible explanation for the improved thermostability of E354K enzyme lies in the formation of a salt bridge between Lys354 and Glu311 and alteration of protein conformation. [ABSTRACT FROM AUTHOR]

This case study describes a 25-year-old patient who had a witnessed cardiac arrest in the medical intensive care unit. The patient received 107 minutes of cardiopulmonary resuscitation before the veno-arterial extracorporeal membrane oxygenation was initiated. During extracorporeal life support, the patient's cardiac function improved. The patient was weaned from extracorporeal membrane oxygenation on day 6 and was discharged without physical and neurological complications on day 28. The successful resuscitation in this case attributed to high-quality CCPR and timely ECMO support. [ABSTRACT FROM AUTHOR]

Nearly twenty years ago, Beaurepaire and coworkers showed that when an ultrafast laser impinges on a ferromagnet, its spin moment undergoes a dramatic change, but how it works remains a mystery. While the current experiment is still unable to resolve the minute details of the spin change, crystal momentum-resolved techniques have long been used to analyze the charge dynamics in superconductors and strongly correlated materials. Here we extend it to probe spin moment change in the entire three-dimensional Brillouin zone for fcc Co. Our results indeed show a strong spin activity along the D line, supporting a prior experimental finding. The spin active pockets coalesce into a series of spin surfaces that follow the Fermi surfaces. We predict two largest spin change pockets which have been elusive to experiments: one pocket is slightly below the Δ line and the other is along the Λ line and close to the L point. Our theory presents an opportunity for the time-, spin- and momentum-resolve photoemission technique. [ABSTRACT FROM AUTHOR]

Inspired by a recent pressure experiment in fcc Ni, we propose a simple method to use pressure to investigate the laser-induced femtosecond magnetism. Since the pressure effect on the electronic and magnetic properties can be well controlled experimentally, this leaves little room for ambiguity when compared with theory. Here we report our theoretical pressure results in fcc Ni: Pressure first suppresses the spin moment reduction and then completely diminishes it; further increase in pressure to 40 GPa induces a demagnetization-to-magnetization transition. To reveal its microscopic origin, we slide through the L-U line in the Brillouin zone and find two essential transitions are responsible for this change, where the pressure lowers two valence bands, resulting in an off-resonant excitation and thus a smaller spin moment reduction. In the spin-richest L-W-W' plane, two spin contours are formed; as pressure increases, the contour size retrieves and its intensity is reduced to zero eventually, fully consistent with the spin-dipole factor prediction. These striking features are detectable in time- and spin-resolved photoemission experiments. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has led to significant morbidity and mortality in lung transplant recipients. Respiratory viral infections may be associated with de-novo HLA donor-specific antibody production and impact lung transplant outcome. Since one of the immunomodulation strategies post-SARS-CoV-2 infection in lung transplant recipients include decreasing or holding anti-metabolites, concerns have been raised for higher incidence of de-novo HLA donor specific antibody production in lung transplant recipients. We performed a retrospective chart review of 24 consecutive lung transplant recipients diagnosed with COVID-19 to investigate this concern. We observed no significant differences in the CPRA or MFI levels of HLA class I and II antibodies pre- COVID-19 compared to 1 and 6 months post-COVID-19 diagnosis in 11/24 (45.8 %) LTR (p = 0.98 and p = 0.63 respectively). HLA class I and II DSA were detected in 5/24 LTR pre-COVID-19 diagnosis and persisted with no significant differences in the median MFI levels at 1 and 6 months post-COVID-19 diagnosis (p = 0.89). De-novo HLA class I and II DSA were detected in 1/24 (4.2 %) LTR at one month post-COVID-19 diagnosis and persisted with no significant differences in the median MFI levels at 1 and 6 months post-COVID-19 diagnosis (p = 0.54). Our results suggest that there was no significant association between SARS-CoV-2 infection and immunomodulation on pre-existing or de novo HLA donor specific antibodies. [ABSTRACT FROM AUTHOR]

Aim: β-amyloid peptides (Aβs) have been shown to block cerebral nitrergic neurogenic vasodilation by blocking sympathetic α7-nAChRs, and that oestrogen prevents Aβ-induced neurotoxicity. We examined whether Aβ-inhibition of α7-nAChR-mediated cerebral nitrergic vasodilation was prevented by oestrogen. Methods: Effects of Aβ and 17β-oestradiol on neurogenic nitrergic vasodilation in isolated porcine basilar arteries were examined using wire-myography. Drug effects on nicotine- and choline-induced calcium influx and inward currents in porcine cultured superior cervical ganglion (SCG) were investigated using confocal microscopy and patch-clamp techniques respectively. Results: Precontracted endothelium-denuded basilar arteries relaxed exclusively upon transmural nerve stimulation (TNS, 8 Hz), and applications of nicotine (100 μ m) or choline (1 m m), which was sensitive to nitro-L-arginine (L-NNA, 30 μ m) and tetrodotoxin (0.3 μ m). The relaxation induced by nicotine and choline but not that by TNS was blocked reversibly by Aβ1-40 in a concentration-dependent manner. Aβ1-40 also reversibly blocked nicotine- and choline-induced increase of calcium influx and inward currents in the SCG neurons. Aβ inhibition of nicotine- and choline-induced α7-nAChR-mediated nitrergic vasodilation and inward currents was prevented by 17β-oestradiol (10 μ m), but not by α-oestradiol (10 μ m) or testosterone (10 μ m). Conclusion: These results provide further evidence supporting that Aβ is an antagonist for the α7-nAChR found on post-ganglionic sympathetic adrenergic nerve terminals originating in the SCG. Aβ can cause constriction of cerebral arteries with possible decreased regional cerebral blood flow by blocking sympathetic nerve-mediated release of nitric oxide from the perivascular nitrergic nerves. This effect of Aβ can be prevented by endogenous oestrogen but not testosterone. [ABSTRACT FROM AUTHOR]

ETHNOPHARMACOLOGICAL RELEVANCE: The radix of Acorus calamus L. (AC) is widely used in the therapy of diabetes in traditional folk medicine of America and Indonesia, and we previously reported the insulin sensitizing activity of the ethyl acetate fraction of AC (ACE). AIM OF THE STUDY: To investigate the insulin releasing and alpha-glucosidase inhibitory activity of ACE in vitro and in vivo. MATERIALS AND METHODS: Insulin releasing and alpha-glucosidase inhibitory effects of different fractions from AC were detected in vitro using HIT-T15 cell line and alpha-glucosidase enzyme. Furthermore, effects of ACE orally on serum glucose were detected in fasted and glucose/amylum challenged normal mice. RESULTS: AC and ACE increased insulin secretion in HIT-T15 cells as gliclazide did. As in vivo results, ACE (400 and 800 mg/kg) significantly decreased fasting serum glucose, and suppressed the increase of blood glucose levels after 2g/kg glucose loading in normal mice. In addition, ACE as a mixed-type inhibitor inhibited alpha-glucosidase activity in vitro with an IC(50) of 0.41 microg/ml, and 100mg/kg of it clearly reduced the increase of blood glucose levels after 5 g/kg amylum loading in normal mice. CONCLUSIONS: Apart from its insulin sensitizing effect, ACE may have hypoglycemic effects via mechanisms of insulin releasing and alpha-glucosidase inhibition, and thus improves postprandial hyperglycemia and cardiovascular complications. [ABSTRACT FROM AUTHOR]

Alteration of VSMC (vascular smooth-muscle cell) physiology is associated with the development of atherosclerosis and restenosis. We hypothesize that aging up-regulates the expression of p16INK4a in VSMCs, which may increase the susceptibility of blood vessels to vascular occlusive diseases. Aortic VSMCs were obtained from young and aged mice. Cells from aged mice grew more slowly than those from their younger counterparts. Progression of cell cycle in response to serum stimulation was significantly inhibited in those cells with aging, as determined by FACS after propidium iodide staining. A significant up-regulation of p16INK4a (2.5-fold, P=0.0012) was found in VSMC from aged animals using gene arrays. The up-regulation of this gene was further confirmed by quantitative RT--PCR (reverse transcription--PCR) and Western-blot experiments. Immunostaining for p16INK4a confirmed that aortas from aged mice contained more p16INK4a+ SMA (smooth-muscle cell actin)+ cells than aortas from young animals (26.79±2.45 versus 7.06±1.44, P=0.00027, n=4). In conclusion, we have shown that aging up-regulates the expression of p16INK4a in VSMC in both cultures and arteries. The increase in p16INK4a in the vasculature with aging may modify VSMC's response to post-injury stress and therefore accelerate the development of age-related cardiovascular diseases. [ABSTRACT FROM AUTHOR]

The soluble guanylyl cyclases (sGC), the receptor for nitric oxide, are heterodimers consisting of an α- and β-subunit. This study aimed to investigate the translational mechanism of the sGC β2-subunit. Two mRNA species for sGC β2 were isolated from human kidney. These transcripts had dissimilar 5′-untranslated regions (5′-UTRs). The most abundant sGC β2 mRNA showed numerous upstream open reading frames (ORFs) and stable secondary structures that inhibited in vivo and in vitro translation . To evaluate whether these 5′-UTRs harbored an internal ribosome entry site (IRES) that allows translation by an alternative mechanism, we inserted these regions between the two luciferase genes of a bicistronic vector. Transfection of those genetic constructs into HeLa cells demonstrated that both sGC β2 leaders had IRES activity in a cell-type dependent manner. Finally, the secondary structural model of the sGC β2 5′-UTR predicts a Y-type pseudoknot that characterizes the IRES of cellular mRNAs. In conclusion, our findings suggest that sGC β2 5′-UTRs have IRES activity that may permit sGC β2 expression under conditions that are not optimal for scanning-dependent translation. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are ∼22 nucleotide non-coding RNA molecules that regulate gene expression post-transcriptionally. Although aberrant expression of miRNAs in various human cancers suggests a role for miRNAs in tumorigenesis, it remains largely unclear as to whether knockdown of a specific miRNA affects tumor growth. In this study, we profiled miRNA expression in matched normal breast tissue and breast tumor tissues by TaqMan real-time polymerase chain reaction miRNA array methods. Consistent with previous findings, we found that miR-21 was highly overexpressed in breast tumors compared to the matched normal breast tissues among 157 human miRNAs analysed. To better evaluate the role of miR-21 in tumorigenesis, we transfected breast cancer MCF-7 cells with anti-miR-21 oligonucleotides and found that anti-miR-21 suppressed both cell growth in vitro and tumor growth in the xenograft mouse model. Furthermore, this anti-miR-21-mediated cell growth inhibition was associated with increased apoptosis and decreased cell proliferation, which could be in part owing to downregulation of the antiapoptotic Bcl-2 in anti-miR-21-treated tumor cells. Together, these results suggest that miR-21 functions as an oncogene and modulates tumorigenesis through regulation of genes such as bcl-2 and thus, it may serve as a novel therapeutic target.Oncogene (2007) 26, 2799–2803. doi:10.1038/sj.onc.1210083; published online 30 October 2006 [ABSTRACT FROM AUTHOR]

We present an effective direct extraction method for particle size distribution based on Bayesian inference theory with a free-form model. We give an example of the application to the particle size distribution analysis in ferrofluid consisting of cobalt particles in toluene. The method gives a unique solution to the distribution without assuming the shape of the distribution of the particle size. [ABSTRACT FROM AUTHOR]

Soluble guanylyl cyclase (sGC) is the only known receptor for nitric oxide (NO) and is downregulated in aging and hypertension. Little is known about sGC gene transcriptional regulation. In order to characterize the sGC transcriptional system, we cloned and sequenced the 5′ flanking region of mouse sGC α1 gene (AY116663). Structurally, it is a non-canonical TATA-less promoter that we mapped to chromosome 3 with many putative regulation sites for Sp-1, NF-κB, and AP-1 transcription factors amongst others, and two (TG:CA)n dinucleotide microsatellites near the transcriptional start point. The cloned upstream sequence produced a 5-fold increase in luciferase activity in Cos7, HeLa, NIH3T3, and 293 cells as well as in mouse VSMC-like kidney mesangial cells. In the latter cell type, we showed that sGC α1 promoter activity was dependent on the presence of its 5′ unstranslated region (5′UTR). [Copyright &y& Elsevier]

Severe primary graft dysfunction (PGD) is a major cause of early mortality after heart transplant, but the impact of donor organ preservation conditions on severity of PGD and survival has not been well characterized. Data from US adult heart-transplant recipients in the Global Utilization and Registry Database for Improved Heart Preservation-Heart Registry (NCT04141605) were analyzed to quantify PGD severity, mortality, and associated risk factors. The independent contributions of organ preservation method (traditional ice storage vs controlled hypothermic preservation) and ischemic time were analyzed using propensity matching and logistic regression. Among 1,061 US adult heart transplants performed between October 2015 and December 2022, controlled hypothermic preservation was associated with a significant reduction in the incidence of severe PGD compared to ice (6.6% [37/559] vs 10.4% [47/452], p = 0.039). Following propensity matching, severe PGD was reduced by 50% (6.0% [17/281] vs 12.1% [34/281], respectively; p = 0.018). The Kaplan-Meier terminal probability of 1-year mortality was 4.2% for recipients without PGD, 7.2% for mild or moderate PGD, and 32.1%, for severe PGD (p < 0.001). The probability of severe PGD increased for both cohorts with longer ischemic time, but donor hearts stored on ice were more likely to develop severe PGD at all ischemic times compared to controlled hypothermic preservation. Severe PGD is the deadliest complication of heart transplantation and is associated with a 7.8-fold increase in probability of 1-year mortality. Controlled hypothermic preservation significantly attenuates the risk of severe PGD and is a simple yet highly effective tool for mitigating post-transplant morbidity. [ABSTRACT FROM AUTHOR]

Introduction: The present study aimed to compare the clinical outcomes of heart transplant patients whose donor hearts were preserved with the SherpaPak controlled cold organ system versus the conventional ice storage technique. Methods: All patients undergoing heart transplantation at our center between January 2019 and April 2021 were divided into two groups according to the technique used during donor heart preservation and transport. The first group consisted of 34 SherpaPak controlled temperature preservation patients, and the second group consisted of 47 patients where the conventional three bags and ice technique was utilized during organ transportation. The two groups were compared based on demographics, operative details, and postoperative outcomes. Results: There were no significant differences between the groups regarding Vasoactive Inotropic Score (VIS), Primary Graft Dysfunction (PGD), and the need for a transient pacer. However, the VIS, PGD, and pacing trends were lower in the SherpaPak patients even though the total ischemic and cardiopulmonary bypass times were significantly longer. Furthermore, SherpaPak patients exhibited a shorter stay in the ICU with no severe PGD and mortality. Conclusion: The SherpaPak donor heart preservation provides safe outcomes in heart transplant patients. Further research is needed to utilize this method for longer durations of ischemic time and expand travel distances for organ transportation. [ABSTRACT FROM AUTHOR]

Background: We aimed to investigate the short‐term outcomes of heart transplant patients who underwent SherpaPak™ donor organ preservation. Method: We prospectively collected the data of patients who underwent heart transplantation using SherpaPak™ system for donor organ transportation from February 2020 to March 2021. Donor and recipient demographic data, preoperative and postoperative echocardiographic and hemodynamic parameters, total ischemic time and SherpaPak temperatures, vasoactive inotropic scores (VIS), primary graft dysfunction (PGD) status, intensive care unit stay, complications, and mortality during follow‐up were assessed. Results: A total of 39 consecutive heart transplant patients with SherpaPak system were included in the study. The mean donor age was 32.2 ± 6.7 (range: 16–46). The mean recipient age was 57.5 ± 12 (range: 19–73). The mean preoperative ejection fraction (EF) was 23.7 ± 15.4 (range: 5–75). All recipients underwent a standard bicaval technique for orthotopic heart implantation. The mean total ischemic time was 230.1 ± 41 (range: 149–342) min. The mean Sherpa temperature was 5.6 ± 0.8°C (range: 3.7–7.5). The mean VIS was 10.2 ± 6.5 (range: 2–32). The number of mild PGD was 5 (14.7%), and moderate PGD was 4 (11.8%). There was no severe PGD. The postoperative EF was 64.3 ± 5.5 (range: 50–78). Mean intubation time was 47.4 ± 64 (range: 8–312, median: 22) h. The mean time of intensive care unit stay was 6.3 ± 5 (range: 2–31, median: 5) days. Two patients required chest revision (5.8%), two patients had lung infection (5.8%). Two patients had a stroke (5.8%). There was no mortality. Conclusion: Using the SherpaPak system during heart transplantation is safe and not associated with significant recipient morbidity. None of the recipients experienced significant PGD and mortality. [ABSTRACT FROM AUTHOR]

This paper conducts a theoretical review of meaningful work at the individual level, organizational level, and society contribution by identifying the limitations of previous research. The Systematic literature review (SLR) was used in this research design using the PRISMA protocol, which systematizes various conceptualizations of meaningful work into a coherent business, management and accounting and psychology study in the 2000-2020 period from 57 relevant articles. The research findings are the first body of literature in this field, the second is the antecedent and consequences variables in previous research and the third is the perspectives harmonization of meaningful work at multi levels that are formed among individual level, organizational levels and contribution to society. The research implication is to identify important issues that can be used in future research about meaningful work studies by replicating new or existing variables. This study is expected to provide a basis consideration for future researchers regarding the antecedents and consequences variables of meaningful work by developing concepts at different levels of analysis but interrelated to provide an in-depth and complementary perspective on the phenomenon of meaningful work with regard to benefits to society. [ABSTRACT FROM AUTHOR]

Carbon nanotubes are good candidates to promote communication between paramagnetic centers at large distances through a highly delocalized π system. Our research uses ab initio methods to predict the equilibrium configuration and magnetic properties of dinuclear iron metal molecular complexes connected by carbon nanotubes. The results show that the presence of surprisingly strong exchange coupling at very large distances for this kind of system and the coupling is ferromagnetic. [ABSTRACT FROM AUTHOR]

α-graphdiyne is a novel predicted Dirac cone material, which is similar to graphene. But the absence of a band gap significantly limits its practical applications. In order to extend this limitation, an opening of energy gap is needed. To this end, we resort to the nanoribbon structure of α-graphdiyne. This is a conventional proposal to open up the energy gaps in nanomaterials. The results show that both the armchair and the zigzag α-graphdiyne nanoribbons do generate energy gaps, which are width-dependent. In addition, the underlying mechanism of this opening is explored. The former is ascribed to the combination of quantum confinement and edges' effect, while the latter arises from the edge magnetic ordering. These novel nanoribbons with opening energy gaps would be potentially used in electronic devices. [ABSTRACT FROM AUTHOR]

The magnetic dipole moment and the electric quadrupole moment are the nuclear moments that provide us with key information about the proton and neutron configurations in a nucleus and the shape of a nucleus, respectively. In the study of nuclear structure through the measurement of the nuclear moments, a technique to produce spin orientation of rare-isotope beams has played important roles. Recently, a scheme of the two-step projectile fragmentation was developed to produce high spin alignment in RI beams and was applied to the frontier of the study for nuclear structure of neutron-rich nuclei, such as 75 Cu and 99 Zr. The recent activities of the nuclear-moment measurements using highly spin-aligned beams at RIKEN RIBF are reported. [ABSTRACT FROM AUTHOR]

Quadricuspid aortic valve is a rare congenital cardiac anomaly with an incidence of 0.008% to 0.043%. Its clinical course varies depending on cusp anatomy, function, and associated cardiac malformations. It frequently progresses to aortic valve regurgitation that may require surgical valve replacement. Detection has shifted from incidental discovery during autopsies or cardiac surgeries in the early 20th century to various cardiac imaging methods in recent decades. In addition to contributing to the literature, this report supports the use of transesophageal echocardiography more liberally to detect aortic valve abnormalities. The case presents a 48-year-old female patient with an incidentally discovered quadricuspid aortic valve. [ABSTRACT FROM AUTHOR]

Diaminoguanidinium and triaminoguanidinium Schiff bases of 1,3‐bis(3,5‐di‐tert‐butyl‐2‐hydroxyphenylmethylideneamino)guanidine hydrochloride (H5saldagtBu2 ⋅ HCl) and tris(3,5‐di‐tert‐butyl‐2‐hydroxybenzylidene)‐triaminoguanidinium chloride (H5saltagtBu2 ⋅ HCl) are synthesized. Treatment of H5saldagtBu2 ⋅ HCl with Na2MoO4 ⋅ 2H2O or (NH4)6Mo7O24 ⋅ 4H2O under different molar ratios afforded mono‐ and di‐nuclear molybdenum(VI) complexes of [(MoO2)(MeOH)(H3saldagtBu2)] (1), [(MoO2)2(MeOH)2(HsaldagtBu2)] ⋅ 2DMF (2 ⋅ 2DMF), and [(MoO2)2(HsaldagtBu2)] ⋅ ‐[(MoO2)2(H2O)2(HsaldagtBu2)] (3). Interactions of H5saltagtBu2 ⋅ HCl with Na2MoO4 ⋅ 2H2O or (NH4)6Mo7O24 ⋅ 4H2O under different reaction conditions resulted mono‐, di‐, and tetra‐nuclear molybdenum(VI) complexes of [(MoO2)(MeOH)(H3saltagtBu2)] (4), [(MoO2)(H2O)(H3saltagtBu2)] (5), [(MoO2)2(H2O)(DMF)(HsaltagtBu2)] ⋅ 3DMF (6) (Ref [31]), and [(MoO2)4(DMF)2(HsaltagtBu2)2] ⋅ 2H2O (7 ⋅ 2H2O). Complexes 1–7 were characterized by IR, 1H NMR and UV/vis spectroscopies. Molecular structures of H5saltagtBu2 ⋅ MeOH, 1, 2 ⋅ 2DMF, 3–5 and 7 ⋅ 2H2O are confirmed by single crystal X‐ray diffraction ananlysis, which shows that the diaminoguanidinium and triaminoguanidinium Schiff bases are coordinated to the cis‐{MoO2}2+ moieties via ONN atoms to form five‐ and six‐membered rings, sharing one Mo−N bond. The catalytic properties of these cis‐dioxo‐molybdenum(VI) complexes for epoxidation of cyclohexene were also investigated. [ABSTRACT FROM AUTHOR]

Lung transplant recipients are at higher risk of developing COVID-19 infection compared to other solid organ transplants. The risk further increases in the unvaccinated patients. We present a case of a 43-year-old male who underwent bilateral sequential lung transplantation for pulmonary alveolar microlithiasis (PAM) and had an uneventful recovery. However, two years post-transplantation, the patient developed chronic lung allograft dysfunction (CLAD) with bronchiolitis obliterans syndrome and two episodes of COVID-19 infection. During the second episode of COVID-19 infection, the patient developed sepsis and multi-organ dysfunction ultimately resulting in death. Our case report highlights the increased susceptibility of PAM patients' post-lung transplant to COVID-19 infection. Continuous follow-up of PAM patients' post-lung transplantation is necessary to prevent unfavorable outcomes. [ABSTRACT FROM AUTHOR]

The structural stabilities of the monoclinic and tetragonal phases of Si-doped HfO2 at finite temperatures were analyzed using a computational scheme to assess the effects of impurity doping. We proposed a method that the finite temperature effects, i.e., lattice vibration and impurity configuration effects, are considered. The results show that 6% Si doping stabilizes the tetragonal phase at room temperature, although a higher concentration of Si is required to stabilize the tetragonal phase at zero temperature. These data indicate that lattice vibration and impurity configuration effects are important factors determining structural stability at finite temperatures. [ABSTRACT FROM AUTHOR]

Congestive heart failure is highly prevalent in the elderly population and left ventricular assist device (LVAD) has been increasingly used in this population. LVAD therapy is more costly than medical treatment but it increases the survival and quality of life of the elderly patients with low disease acuity. Therefore careful selection of candidates and implementation of LVAD therapy earlier in the course of the disease is crucial to improve outcomes. With the technical advances and improvement in clinical management, the financial burden of LVAD therapy in the elderly will become less, making this therapy more economically feasible. [ABSTRACT FROM AUTHOR]

Information technology depends on how one can control and manipulate signals accurately and quickly. Transistors are at the core of modern technology and are based on electron charges. But as the device dimension shrinks, heating becomes a major problem. The spintronics explores the spin degree of electrons and thus bypasses the heat, at least in principle. For this reason, spin-based technology offers a possible solution. In this review, we survey some of the latest developments in all-optical switching (AOS), where ultrafast laser pulses are able to reverse spins from one direction to the other deterministically. But AOS only occurs in a special group of magnetic samples and within a narrow window of laser parameters. Some samples need multiple pulses to switch spins, while others need a single-shot pulse. To this end, there are several models available, but the underlying mechanism is still under debate. This review is different from other prior reviews in two aspects. First, we sacrifice the completeness of reviewing existing studies, while focusing on a limited set of experimental results that are highly reproducible in different labs and provide actual switched magnetic domain images. Second, we extract the common features from existing experiments that are critical to AOS, without favoring a particular switching mechanism. We emphasize that given the limited experimental data, it is really premature to identify a unified mechanism. We compare these features with our own model prediction, without resorting to a phenomenological scheme. We hope that this review serves the broad readership well. [ABSTRACT FROM AUTHOR]

We report a case of iatrogenic acute type A aortic dissection (ATAAD) during a combined heart-liver transplant in a patient with amyloid-associated cardiac and hepatic failure. The patient developed ATAAD of the recipient's aorta during the heart transplantation. Because there was no sign of malperfusion or proximal extension into the donor aorta, we proceeded with the liver transplantation and continued medical management for ATAAD. The patient was discharged uneventfully 30 days after the transplant, and computed tomography coronary angiogram after 4 months showed stable dissection. During a heart transplant, ATAAD of the native aorta without malperfusion syndrome can be managed conservatively with close progress monitoring. [ABSTRACT FROM AUTHOR]

Background: Coronavirus (COVID‐19) infection exposes patients with heart failure specially who are on mechanical support to a higher risk of morbidity and mortality. Aims: To investigate the impact of COVID‐19 infection on left ventricular assist device (LVAD) thrombosis in heart failure patients. Materials & Methods: We searched the medical electronic records, Medline, PubMed and Cochrane databases for; (LVAD) AND (thrombosis)) AND (covid‐19)) AND (heart failure). We divided cases reported into, LVAD thrombosis with COVID‐19 infection and compare them with LVAD thrombosis without COVID‐19 infection. Demographic data, LVAD device, presentation, treatment and outcomes were reviewed in all the LVAD thrombosis patients. Results: In addition to our case, 8 other cases of LVAD thrombosis associated with COVID and 9 cases of LVAD thrombosis without covid infection were found. Patients with Covid infection had worse presentation and outcomes (3 deaths VS. 1 death in non‐covid group). Discussion: In LVAD patients, pump malfunction due to thrombus development in the inflow cannula, device body, or outflow graft can result in hemodynamic instability, hemolysis and other life‐threatening complications. COVID infection significantly increases the risk of mortality in LVAD patient by accelerating the pump thrombosis due to elevated levels of endothelial protein C receptor and thrombomodulin along with procoagulants such as factor VIII, P‐selectin, and von Willebrand factor. Conclusion: Significant morbidity and mortality are attributed to LVAD thrombosis, which are exasperated by prothrombotic conditions created in COVID‐19 infections. [ABSTRACT FROM AUTHOR]

• Tricuspid regurgitation (TR) improved overall after lung transplant without tricuspid valve repair. • Forgoing tricuspid valve repair during lung transplant, and thus possible TR posttransplant, can be safe. • Severe TR with pulmonary hypertension and other conditions may need surgical repair. Although tricuspid regurgitation (TR) is common in candidates for lung transplant, no data or established guidelines exist regarding the need for surgical repair at the time of transplant. We aimed to evaluate the natural course of TR by assessing the incidence and extent of TR regression among patients who did not undergo tricuspid valve repair (TVR) concomitantly with lung transplant. We retrospectively identified adult patients who underwent lung transplant without TVR at our institution from 2001 through 2017. Pretransplant and posttransplant echocardiograms were reviewed to assess severity of TR, tricuspid annular plane systolic excursion, central venous pressure, mean pulmonary arterial pressure, and right ventricular size and function. Among 553 included patients, 324 (58.7%) were men, the mean (SD) age was 61.9 years (12.7), and 417 (75.4%) had a double lung transplant. TR before transplant was reported as trivial in 265 patients (47.9%), mild in 235 (42.5%), moderate in 40 (7.2%), and severe in 13 (2.4%). After transplant, TR improved significantly overall (P <.001). TR improved in 193 patients: 158 patients (81.9%) by 1 grade and 35 patients (18.1%) by 2 or more grades. Additionally, of 53 patients with pretransplant moderate or severe TR, 44 (83%) had improvement to mild, trivial, or no TR. After transplant, 12 patients (2.2%) had no remaining TR. The severity of TR improved or showed no change in most patients after lung transplant, which obviates the need for TVR among most lung transplant recipients. [ABSTRACT FROM AUTHOR]

The role of oxidative stress and leukocyte activation has not been elucidated in developing systemic inflammatory response syndrome ( SIRS) in heart failure ( HF) patients after continuous-flow left ventricular assist device ( CF-LVAD) implantation. The objective of this study was to investigate the change of plasma redox status and leukocyte activation in CF-LVAD implanted HF patients with or without SIRS. We recruited 31 CF-LVAD implanted HF patients (16 SIRS and 15 non- SIRS) and 11 healthy volunteers as the control. Pre- and postimplant blood samples were collected from the HF patients. Plasma levels of oxidized low-density lipoprotein ( oxLDL), malondialdehyde ( MDA), total antioxidant capacity ( TAC), superoxide dismutase ( SOD) in erythrocyte, myeloperoxidase ( MPO), and polymorphonuclear elastase ( PMN-elastase) were measured. The HF patients had a preexisting condition of oxidative stress than healthy controls as evident from the higher oxLDL and MDA levels as well as depleted SOD and TAC. Leukocyte activation in terms of higher plasma MPO and PMN-elastase was also prominent in HF patients than controls. Persistent oxidative stress and reduced antioxidant status were found to be more belligerent in HF patients with SIRS after the implantation of CF-LVAD when compared with non- SIRS patients. Similar to oxidative stress, the activation of blood leukocyte was significantly highlighted in SIRS patients after implantation compared with non- SIRS. We identified that the plasma redox status and leukocyte activation became more prominent in CF-LVAD implanted HF patients who developed SIRS. Our findings suggest that plasma biomarkers of oxidative stress and leukocyte activation may be associated with the development of SIRS after CF-LVAD implant surgery. [ABSTRACT FROM AUTHOR]

The carbon fiber reinforced silicon carbide matrix (C/SiC) composites were prepared by using precursor infiltration and pyrolysis method. Fracture characteristics of C/SiC materials were studied by single edge notched beam with the aid of digital image correlation (DIC) technique. It was found that DIC played an important role in in-situ monitoring full/local strain evolution and cracking growth during bending tests, which was useful for revealing potential failure micro-mechanisms of C/SiC composites. The results showed that the average fracture toughness KIC and fracture strength of C/SiC were estimated as 7.81±0.12 MPa m1/2 and 223.23±3.5 MPa, respectively. Moreover, the crack extension resistance curves (R-curve) in terms of stress intensity (KR-curves) were determined on the basis of the crack initiation toughness KIC. The values varied from 4.68 MPa m1/2 to 16.83 MPa m1/2 during the R-curve tests. [ABSTRACT FROM AUTHOR]

This Part 3 of the paper series on jack-up model tests describes the model test design and selected results for transit conditions. As part of the summary for the paper series, uncertainty analysis for the entire jack-up model tests was also conducted and presented. Operating scenarios were simulated, covering jack-up model with legs extended above the hull as well as legs partially submerged into the water. Soft moorings were used to provide horizontal restraint onto the jack-up model. Long-crested waves without and with co-linear uniform current were used throughout the tests, with current meant to simulate sea-keeping and wet towing conditions. Reduced motions in surge and pitch were observed for the jack-up with legs partially submerged into the water, demonstrating additional damping to be gained, but at the expense of increased towing drag forces. Additional measurements in terms of bending moment at the leg-to-hull connection as well as shear forces on the starboard leg were also compared. Uncertainty analysis was conducted for the entire jack-up model test to quantify the errors and confidence level of the presented results. • Jack-up platform was tested for transit conditions. • Two scenarios: legs all above the hull & legs partially into the water. • Soft-mooring system was used to prevent the jack-up from drifting. • Reduced motions for legs partially into the water due to additional fluid damping. • Uncertainty analysis was done to quantify errors & confidence level of the results. [ABSTRACT FROM AUTHOR]

Transesophageal echocardiography (TEE) has become an indispensable part of cardiac surgery, but its potential for assessing coronary anatomy and blood flow remains underutilised. This case report presents a case of acute iatrogenic left main coronary artery obstruction following re-operative aortic valve replacement that was promptly diagnosed by intraoperative TEE and managed successfully by Bentall operation. We also emphasise the technique of TEE for coronary evaluation, its caveats and its clinical application during cardiac surgery. [ABSTRACT FROM AUTHOR]

Background: Donation after circulatory death is the donation after cardiac arrest. This technique has been employed and adopted by clinicians to overcome the shortage of available hearts for transplant. Warm ischemia time plays a pivotal role in the survival outcome of the heart recipients. Aim of the study: To assess the efficacy of using the Foley catheter to flush the heart during procurement from donation after circulatory death donors. Methods: We utilized a 2‐WAY Foley catheter to flush the heart during procurement. The catheter was prepared and modified on the back table. Results: We were successfully able to flush the heart within 3 minutes from skin incision with a good recipient outcome. Conclusions: Using the Foley catheter to flush the heart during recovery from donation after circulatory death donors was both efficient and fast. [ABSTRACT FROM AUTHOR]

Ultrafast spin dynamics in Tbx(FeCo)1-x films is studied using the time-resolved magneto-optical Kerr effect. At pump fluence of 1.0 mJ/cm^2 the ultrafast demagnetization processes are accomplished by one-step and two-step decays (the first fast and second slow decays) for low and high Tb contents, respectively. For the low Tb contents (x < 0.08), the demagnetization time is almost a constant (\sim 600 fs), which is similar with the demagnetization time (\tau_1) of the first fast decay for the high Tb contents due to bleaching effect. However, the following slow demagnetization time (\tau_2) for the high Tb contents strongly depends on the Tb contents. It increases with increasing Tb contents, and reaches a maximum of 3.0 ps at x=0.21, then decreases with Tb content further increasing. The distinguished slow decay process is suggested to ascribe to the Gilbert damping factor. [ABSTRACT FROM AUTHOR]

Background and Purpose: Modulation of K(v)7/M channel function represents a relatively new strategy to treat neuronal excitability disorders such as epilepsy and neuropathic pain. We designed and synthesized a novel series of pyrazolo[1,5-a] pyrimidin-7(4H)-one compounds, which activate K(v)7 channels. Here, we characterized the effects of the lead compound, QO-58, on K(v)7 channels and investigated its mechanism of action.Experimental Approach: A perforated whole-cell patch technique was used to record K(v)7 currents expressed in mammalian cell lines and M-type currents from rat dorsal root ganglion neurons. The effects of QO-58 in a rat model of neuropathic pain, chronic constriction injury (CCI) of the sciatic nerve, were also examined.Key Results: QO-58 increased the current amplitudes, shifted the voltage-dependent activation curve in a more negative direction and slowed the deactivation of K(v)7.2/K(v)7.3 currents. QO-58 activated K(v)7.1, K(v)7.2, K(v)7.4 and K(v)7.3/K(v)7.5 channels with a more selective effect on K(v)7.2 and K(v)7.4, but little effect on K(v)7.3. The mechanism of QO-58's activation of K(v)7 channels was clearly distinct from that used by retigabine. A chain of amino acids, Val(224)Val(225)Tyr(226), in K(v)7.2 was important for QO-58 activation of this channel. QO-58 enhanced native neuronal M currents, resulting in depression of evoked action potentials. QO-58 also elevated the pain threshold of neuropathic pain in the sciatic nerve CCI model.Conclusions and Implications: The results indicate that QO-58 is a potent modulator of K(v)7 channels with a mechanism of action different from those of known K(v)7 openers. Hence, QO-58 shows potential as a treatment for diseases associated with neuronal hyperexcitability. [ABSTRACT FROM AUTHOR]

Abstract: Background and aims: In-stent restenosis (ISR) is the major complication that occurs after percutaneous coronary interventions to facilitate coronary revascularization. Herein we described a simple and cost-effective model, which reproduces important features of ISR in the mouse. Methods and results: Microvascular bare metal stents were successfully implanted in the abdominal aorta of atherosclerotic ApoE-null mice. Patency of implanted stents was interrogated using ultrasound biomicroscopy. Aortas were harvested at different time points after implantation and processed for histopathological analysis. Thrombus formation was histologically detected after 1 day. Leukocyte adherence and infiltration were evident after 7 days and decreased thereafter. Neointimal formation, neointimal thickness and luminal stenosis simultaneously increased up to 28 days after stent implantation. Using multichannel fluorescence molecular tomography (FMT) for spatiotemporal resolution of MMP activities, we observed that MMP activity in the stented aorta of Apo-E null mice was 2-fold higher than that of wild-type mice. Finally, we compared neointimal formation in response to stenting in two genetically different mouse strains. In-stent neointimas in FVB/NJ mice were 2-fold thicker than in C57BL/6J mice (p =0.002). Conclusion: We have developed a model that can take advantage of the multiple genetic resources available for the mouse to study the mechanisms of in-stent restenosis. [Copyright &y& Elsevier]

The use of VADs as a BTT in children with heart failure has increased due to enhanced device design and reliability, leading to improved survival, functional capacity, and quality of life. However, the use of VADs in patients with Fontan physiology as a BTT is rare with few case reports. Here, we describe a case of implantation of the Berlin VAD as a BTT for 179 days, one of the longest reported periods of mechanical support, in a child with failing single ventricle. [ABSTRACT FROM AUTHOR]

Current-induced spin–orbit torque (SOT) allows for highly efficient control of magnetization for the magnetic memory and the logic application, but its high critical current density Jc limits its applications. Here, we report that the surface acoustic wave (SAW) presents a promising approach for reducing Jc in Pt/Co/Ta heterostructures with perpendicular anisotropy. By the second harmonic Hall measurements, we find that the damping-like SOT effective field is almost the same with or without SAW, implying that the reduction of Jc does not originate from the enhancement of the SOT. However, the current-induced domain wall velocity v under SAW is greatly enhanced. By fitting with the creep law under SAW, we find that lnv is linear with SAW power (P), which reveals that the effective pinning barrier is reduced linearly with increasing P. This feature can be well described by the time average of the periodically accumulated nucleation probability under SAW. The results shed light on the application of SAW-assisted SOT devices for low consumption storage. [ABSTRACT FROM AUTHOR]