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1.
J Vet Med Sci ; 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37704451

RESUMO

To our knowledge, ours is the first case of applying a 3D-printed prosthetic beak to an Oriental stork (Ciconia boyciana). A stork in captivity underwent several surgeries for beak fractures, but the lower-mandible fractures failed to be repaired. Therefore, we applied a patient-specific beak prosthesis of titanium alloy and nylon. Because the prosthetic beak could not be maintained due to mandible and soft-tissue inflammation, the stork was euthanized. Still, we confirmed typical behavior and feeding for ~3 months after surgery. This report highlights some of the challenges we encountered and identifies process improvements required for a more successful surgery.

2.
J Ginseng Res ; 47(5): 638-644, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37720569

RESUMO

Background: The anti-platelet activity of the saponin fraction of Korean Red Ginseng has been widely studied. The saponin fraction consists of the panaxadiol fraction (PDF) and panaxatriol fraction (PTF); however, their anti-platelet activity is yet to be compared. Our study aimed to investigate the potency of anti-platelet activity of PDF and PTF and to elucidate how well they retain their anti-platelet activity via different administration routes. Methods: For ex vivo studies, Sprague-Dawley rats were orally administered 250 mg/kg PDF and PTF for 7 consecutive days before blood collection via cardiac puncture. Platelet aggregation was conducted after isolation of the washed platelets. For in vitro studies, washed platelets were obtained from Sprague-Dawley rats. Collagen and adenosine diphosphate (ADP) were used to induce platelet aggregation. Collagen was used as an agonist for assaying adenosine triphosphate release, thromboxane B2, serotonin, cyclic adenosine monophosphate, and cyclic guanosine monophosphate (cGMP) release. Results: When treated ex vivo, PDF not only inhibited ADP and collagen-induced platelet aggregation, but also upregulated cGMP levels and reduced platelet adhesion to fibronectin. Furthermore, it also inhibited Akt phosphorylation induced by collagen treatment. Panaxadiol fraction did not exert any anti-platelet activity in vitro, whereas PTF exhibited potent anti-platelet activity, inhibiting ADP, collagen, and thrombin-induced platelet aggregation, but significantly elevated levels of cGMP. Conclusion: Our study showed that in vitro and ex vivo PDF and PTF treatments exhibited different potency levels, indicating possible metabolic conversions of ginsenosides, which altered the content of ginsenosides capable of preventing platelet aggregation.

3.
Cancer Res Treat ; 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37475136

RESUMO

Purpose: Precision oncology approach for recurrent and metastatic head and neck squamous cell carcinoma (HNSCC) is necessary due to its dismal prognosis. We performed a genomic profile-based umbrella trial of patients with platinum-refractory HNSCC (KCSG-TRIUMPH). Here, we present an in-depth report of the the nintedanib arm (arm 3) of the current trial. Materials and Methods: The TRIUMPH study was a multicenter, open-label, single-arm phase 2 trial, in which patients were assigned to treatment arms based on NGS-based, matching genomic profiles. Patients whose tumors harbor FGFR alteration were enrolled in the nintedanib arm (arm 3) as part of the TRIUMPH study. The primary endpoint was the overall response rate (ORR), and secondary endpoints included overall survival (OS), progression-free survival (PFS), safety, and biomarker analysis. Results: Between Oct 2017 and Aug 2020, 207 were enrolled in the TRIUMPH study, and 8 were enrolled in the nintedanib arm. ORR and disease control rate were 42.9% and 57.1%, respectively. The median PFS was 5.6 months and the median duration of response was 9.1 months. Median OS was 11.1 months. One patient maintained the PR for 36 months. Overall, the toxicity profiles were manageable. Conclusion: Single-agent nintedanib has demonstrated significant efficacy in FGFR-mutated, recurrent, or metastatic HNSCC patients, with tolerable toxicity profiles. The results from the study have provided the basis for routine NGS screening and FGFR-targeted therapy. Because of small number of patients due to slow accrual in this study, further studies with large cohort are warranted for statistical power.

4.
Nano Converg ; 10(1): 32, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37418068

RESUMO

The thermoelectric performance of SnSe strongly depends on its low-energy electron band structure that provides high density of states in a narrow energy window due to the multi-valley valence band maximum (VBM). Angle-resolved photoemission spectroscopy measurements, in conjunction with first-principles calculations, reveal that the binding energy of the VBM of SnSe is tuned by the population of Sn vacancy, which is determined by the cooling rate during the sample growth. The VBM shift follows precisely the behavior of the thermoelectric power factor, while the effective mass is barely modified upon changing the population of Sn vacancies. These findings indicate that the low-energy electron band structure is closely correlated with the high thermoelectric performance of hole-doped SnSe, providing a viable route toward engineering the intrinsic defect-induced thermoelectric performance via the sample growth condition without an additional ex-situ process.

5.
Parasites Hosts Dis ; 61(2): 210-215, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37258269

RESUMO

Toxoplasmosis is a major public health concern, with raw or undercooked meat being the primary source of human infection. Knowledge regarding the molecular epidemiology of Toxoplasma gondii in cattle destined for human consumption in Korea is lacking. The present study aimed to genetically characterize the infectious strains of T. gondii. Overall, 455 cattle blood samples from 84 farms in the Gyeongnam-do (Province) were randomly collected in 2017. Nested PCR analysis revealed that only 3 (0.7%) samples were infected with T. gondii. The B1 gene sequence of T. gondii was observed to be similar (97.3-99.6%) to that of other T. gondii isolates. This is the first study to perform the molecular detection of T. gondii in cattle in Korea. Although the prevalence of infection was low, our findings suggest that cattle present a potential public health issue. It may be crucial to recognize the importance of T. gondii infection in cattle meat.


Assuntos
Toxoplasma , Toxoplasmose Animal , Animais , Humanos , Bovinos , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Epidemiologia Molecular , Carne , República da Coreia/epidemiologia
6.
Acta Trop ; 243: 106934, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37142151

RESUMO

Ticks are widespread in nature and serve as primary vectors for several tick-borne pathogens (TBPs). Ticks and TBPs cause considerable harm to humans and animals and have emerged as a major global public health concern. Domestic dogs are the major reservoirs of zoonotic agents owing to their constant interaction with humans. This study aimed to assess the prevalence and risk factors of canine TBPs, such as Rickettsiales, Coxiella burnetii, hepatozoa, and Borrelia spp., using molecular analyses. A total of 906 dogs were examined and 4 TBPs were identified: Anaplasma phagocytophilum (5; 0.6%), Hepatozoon canis (9; 1.0%), Candidatus Rickettsia longicornii (2; 0.2%), and Rickettsia tamurae (1; 0.1%). Ehrlichia spp., C. burnetii, and Borrelia spp. were not detected. To the best of our knowledge, this is the first study to perform a phylogenetic analysis of Candidatus R. longicornii and R. tamurae in dogs. These findings can help determine the potential public health risks by enhancing our understanding of the geographical and vector distributions of TBPs in Korea.


Assuntos
Borrelia , Doenças do Cão , Rickettsia , Doenças Transmitidas por Carrapatos , Carrapatos , Humanos , Animais , Cães , Carrapatos/microbiologia , Filogenia , Rickettsia/genética , Ehrlichia , República da Coreia/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária , Doenças Transmitidas por Carrapatos/microbiologia , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia
7.
Microorganisms ; 11(4)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37110242

RESUMO

The present study was performed to survey the dominant tick populations and molecularly determine the pathogenic agents of anaplasmosis in ticks from Gyeongsang, Republic of Korea. A total of 3825 questing ticks were collected by the flagging method from 12 sites near animal farms in Gyeongsang from March to October 2021. A molecular genomic study was performed with ticks stored in 70% ethanol to detect Anaplasma genes by the previously described method. The monthly incidence of ticks varied by developmental stages, i.e., nymphs, adults, and larvae, and each of their populations peaked in May, March, and October, respectively. The predominant tick species were Haemaphysalis longicornis, Haemaphysalis sp., Haemaphysalis flava, Ixodes nipponensis, and Amblyomma testudinarium in order. To determine the Anaplasma infection rate, collected ticks were pooled into 395 groups. The minimum infection rate (MIR) of Anaplasma was 0.7% (27 pools). That of A. phagocytophilum was highest (23 pools, MIR 0.6%), followed by A. phagocytophilum-like Anaplasma spp. clade B (2 pools, MIR 0.1%), A. bovis (1 pool, MIR 0.1%), and A. capra (1 pool, MIR 0.1%), respectively. In this study, five species of ticks, including unidentified Haemaphysalis species, were collected in 12 survey sites in Gyeongsang, but their prevalence was somewhat different according to the tick species and survey sites. Further, the incidence rate (6.8%) of 4 Anaplasma spp. was not as high in tick pools. However, the results of this study may offer a basis for future epidemiological research and risk assessment of tick-borne diseases.

8.
J Vet Med Sci ; 85(5): 584-586, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-36927695

RESUMO

A two-week-old white-tailed eagle presented with an inability to stand and flex its limbs. Despite hatching naturally and owing to lack of parental attention, the bird was raised indoors by zookeepers with no access to sunlight. Palpation and radiographic examination of the bilateral tibiotarsus and femur bone revealed pronounced deformation and curvature, and bilateral decreased bone densities, respectively. The reduced calcium concentration in the blood was treated with calcium gluconate injections and calcium-supplemented feeds. Chopped mouse tails were fed directly, and whole pink-skinned nude mice were fed weekly. The zookeeper also gently massaged the bird and dressed it with a bandage. Sunlight exposure was provided daily. Saliva containing chicken feed was obtained from the mother. The bird could stand properly after four weeks of treatment, and the blood calcium concentration was restored to normal levels.


Assuntos
Águias , Raquitismo , Doenças dos Roedores , Animais , Camundongos , Galinhas , Cálcio , Camundongos Nus , Raquitismo/veterinária
9.
J Vet Med Sci ; 85(4): 528-531, 2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-36878554

RESUMO

Aeromonas hydrophila is a facultative anaerobic gram-negative bacterium regarded as an opportunistic pathogen in animals. A 17-year-old female crab-eating macaque (Macaca fascicularis) died after experiencing anorexia and depression for several days. The carcass was severely emaciated, and the sternum was exposed under subcutaneous lesions in the thorax. Many abnormal pathological lesions were found, including tracheal inflammation, pulmonary inflammatory emphysema, yellowish discoloration of the liver, enlargement of the gall bladder, necrosis of the heart, congested bilateral kidneys, and enlargement of the adrenal glands. The stomach was empty, mucosal ulcerations were found, and the duodenum was congested. Giemsa staining revealed rod-shaped organisms in the whole blood smear and major organs, which were identified as A. hydrophila. The animal had experienced stress, and decreased immune system function possibly contributed to the infection.


Assuntos
Aeromonas hydrophila , Infecções por Bactérias Gram-Negativas , Macaca fascicularis , Animais , Feminino , Aeromonas hydrophila/isolamento & purificação , Morte Súbita/etiologia , Morte Súbita/veterinária , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/veterinária , Macaca fascicularis/microbiologia , Macaca fascicularis/psicologia , Animais de Zoológico/microbiologia , Animais de Zoológico/psicologia , Estresse Psicológico/complicações
10.
Cancer Res Treat ; 55(3): 746-757, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36758955

RESUMO

PURPOSE: We aimed to assess the humoral response to and reactogenicity of coronavirus disease 2019 (COVID-19) vaccination according to the vaccine type and to analyze factors associated with immunogenicity in actively treated solid cancer patients (CPs). Materials and Methods: Prospective cohorts of CPs, undergoing anticancer treatment, and healthcare workers (HCWs) were established. The participants had no history of previous COVID-19 and received either mRNA-based or adenovirus vector-based (AdV) vaccines as the primary series. Blood samples were collected before the first vaccination and after 2 weeks for each dose vaccination. Spike-specific binding antibodies (bAbs) in all participants and neutralizing antibodies (nAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) wild-type, Delta, and Omicron variants in CPs were analyzed and presented as the geometric mean titer. RESULTS: Age-matched 20 HCWs and 118 CPs were included in the analysis. The bAb seroconversion rate and antibody concentrations after the first vaccination were significantly lower in CPs than in HCWs. After the third vaccination, antibody levels in CPs with a primary series of AdV were comparable to those in HCWs, but nAb titers against the Omicron variant did not quantitatively increase in CPs with AdV vaccine as the primary series. The incidence and severity of adverse reactions post-vaccination were similar between CPs and HCWs. CONCLUSION: CPs displayed delayed humoral immune response after SARS-CoV-2 vaccination. The booster dose elicited comparable bAb concentrations between CPs and HCWs, regardless of the primary vaccine type. Neutralization against the Omicron variant was not robustly elicited following the booster dose in some CPs, implying the need for additional interventions to protect them from COVID-19.


Assuntos
COVID-19 , Neoplasias , Vacinas , Humanos , Estudos Prospectivos , Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , SARS-CoV-2 , Neoplasias/terapia , Anticorpos
11.
J Vet Sci ; 24(1): e17, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36726282

RESUMO

To our knowledge, this is the first case of concurrent diaphyseal left coracoid and left femoral fractures in a Eurasian eagle owl and its post-release survival in Korea. The femur was surgically repaired using an external skeletal fixator-intramedullary (IM) pin tie-in method, and the coracoid was repaired solely with an IM pin on day 6 after femur surgery. The eagle owl underwent a gradual rehabilitation process. The bird was successfully rehabilitated and released 101 d after initial presentation. The bird was monitored using a wildlife tracking device and was confirmed to have survived for over 5 mon in the wild.


Assuntos
Fraturas Ósseas , Estrigiformes , Animais , Fraturas Ósseas/veterinária , Animais Selvagens , Fêmur/cirurgia
12.
J Phys Condens Matter ; 34(47)2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36174545

RESUMO

We report the magnetic phase transitions of a spin-5/2, 2-dimensional triangular lattice antiferromagnet (AFM) Na2BaMn(PO4)2. From specific heat measurements, we observe two magnetic transitions at temperatures 1.15 and 1.30 K at zero magnetic field. Detailed AC magnetic susceptibility measurements reveal multiple phases including the↑↑↓(up-up-down)-phase between 1.9 and 2.9 T at 47 mK when magnetic field is applied along thecaxis, implying that Na2BaMn(PO4)2is a classical 2dTL Heisenberg AFM with easy-axis anisotropy. However, it deviates from an ideal model as evidenced by a hump region with hysteresis between the↑↑↓andV-phases and weak phase transitions. Our work provides another experimental example to study frustrated magnetism in 2dTL AFM which also serves as a reference to understand the possible quantum spin liquid behavior and anomalous phase diagrams observed in sibling systems Na2BaM(PO4)2(M= Co, Ni).

13.
J Am Acad Dermatol ; 87(5): 989-996, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36068115

RESUMO

BACKGROUND: Limited data are available to assist the selection between immune checkpoint inhibitors and BRAF/mitogen-activated protein kinase kinase inhibitors as first-line treatment for patients with BRAF-mutant advanced malignant melanoma. OBJECTIVE: To investigate the outcomes associated with first-line pembrolizumab or dabrafenib/trametinib treatment for advanced melanoma with activating BRAF V600 mutation. METHODS: Data of patients with BRAF V600-mutant melanoma who were treated with first-line pembrolizumab (n = 40) or dabrafenib/trametinib (n = 32) were analyzed. Tumor response, progression-free survival, and overall survival were evaluated. Immune evasion accompanied with emerging resistance to BRAF/mitogen-activated protein kinase kinase inhibitors was assessed. RESULTS: A longer overall survival was observed after first-line pembrolizumab treatment than after first-line dabrafenib/trametinib treatment (hazard ratio = 2.910, 95% CI: 1.552-5.459), although there were no significant differences in progression-free survival (P = .375) and response rate (P = .123). Emergence of resistance to dabrafenib/trametinib co-occurred with immune evasion, enabling melanoma cells to escape recognition and killing by Melan-A-specific CD8+ T cells. LIMITATIONS: Analysis was conducted in a retrospective manner. CONCLUSION: Pembrolizumab may be recommended over BRAF/mitogen-activated protein kinase kinase inhibitors as the first-line treatment in patients with advanced BRAF V600-mutant melanoma.


Assuntos
Melanoma , Neoplasias Cutâneas , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfócitos T CD8-Positivos/patologia , Humanos , Imidazóis , Inibidores de Checkpoint Imunológico , Antígeno MART-1 , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno , Mutação , Oximas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Piridonas/efeitos adversos , Pirimidinonas , Estudos Retrospectivos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
14.
Korean J Parasitol ; 60(4): 289-293, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36041491

RESUMO

Blastocystis is a genus of unicellular heterokont parasites belonging to a group of organisms known as Stramenopiles, which includes algae, diatoms, and water molds. Blastocystis includes several species that habitat in the gastrointestinal tracts of organisms as diverse as humans, farm animals, birds, rodents, reptiles, amphibians, fish, and cockroaches. It is important to public health and distributed globally, but its prevalence in dogs in Korea has not been reported to date. Here, we collected 787 canine fecal samples and assessed Blastocystis infection by age, sex, region, season, and diarrhea symptoms. We determined Blastocystis subtypes using phylogenetic analyses based on 18S rRNA gene sequences. We identified, 10 Blastocystis positive samples (1.3%). A higher proportion of infected dogs was asymptomatic; however, infection rates did not significantly differ according to region, age, sex, and season. Phylogenetic analysis showed that the Blastocystis sp. identified belonged to 4 subtypes (STs), ST1, ST5, ST10, and ST14, thus revealed the genetic diversity of Blastocystis sp. in dogs Korean. This is first report on the presence of Blastocystis sp. in dogs Korean. This study revealed a lower infection rate than expected and differed from previous studies in STs. Further studies are warranted to observe the national infection status of Blastocystis in dogs and the genetic characteristics of this genus.


Assuntos
Infecções por Blastocystis , Blastocystis , Animais , Blastocystis/genética , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , Infecções por Blastocystis/veterinária , Cães , Fezes/parasitologia , Variação Genética , Humanos , Filogenia , Prevalência
15.
Adv Mater ; 34(38): e2204579, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35902365

RESUMO

The spontaneous formation of electronic orders is a crucial element for understanding complex quantum states and engineering heterostructures in 2D materials. A novel 19 $\sqrt {19} $ × 19 $\sqrt {19} $ charge order in few-layer-thick 1T-TaTe2 transition metal dichalcogenide films grown by molecular beam epitaxy, which has not been realized, is report. The photoemission and scanning probe measurements demonstrate that monolayer 1T-TaTe2 exhibits a variety of metastable charge density wave orders, including the 19 $\sqrt {19} $ × 19 $\sqrt {19} $ superstructure, which can be selectively stabilized by controlling the post-growth annealing temperature. Moreover, it is found that only the 19 $\sqrt {19} $ × 19 $\sqrt {19} $ order persists in 1T-TaTe2 films thicker than a monolayer, up to 8 layers. The findings identify the previously unrealized novel electronic order in a much-studied transition metal dichalcogenide and provide a viable route to control it within the epitaxial growth process.

16.
J Med Econ ; 25(1): 274-281, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35125049

RESUMO

AIM: To evaluate the cost utility of adjunct racecadotril and oral rehydration solution (R + ORS) versus oral rehydration solution (ORS) alone for the treatment of diarrhoea in children under five years with acute watery diarrhoea in four low-middle income countries. METHOD: A cost utility model, previously developed and independently validated, has been adapted to Egypt, Morocco, Philippines and Vietnam. The model is a decision tree, cohort model programmed in Microsoft Excel. The model structure represents the country-specific clinical pathways. The target population is children under the age of five years presenting with symptoms of acute watery diarrhea to an outpatient clinic or general physician practice. A healthcare payer perspective has been analysed with the model parameterised with local data, where available. Most recent cost data has been used to inform the drug, outpatient and inpatient costs. Uncertainty has been explored with univariate deterministic sensitivity. RESULTS: According to the base case models, R + ORS is dominant (cost-saving, more effective) versus ORS alone in Egypt, Morocco, Philippines and Vietnam. The incremental cost-effectiveness ratios in each country fall in the southeast (cost-saving, more effective) quadrant and represent a cost savings of -304,152 EGP per QALY gain in Egypt; -6,561 MAD per QALY gain in Morocco; -428,612 PHP per QALY gain in Philippines and -113,985,734 VND per QALY gain in Vietnam. Univariate deterministic sensitivity analysis shows that the three most influential parameters across all country adaptations are the utility of children without diarrhea; the utility of inpatient children with diarrhea and the cost of one night of inpatient care. CONCLUSION: In keeping with similar findings in upper-middle and high-income countries, the cost utility of R + ORS versus ORS is favourable in low-middle income countries for the treatment of children under five with acute watery diarrhoea.


PLAIN LANGUAGE SUMMARYDecision-makers rely on cost utility models to inform decisions about whether to publicly fund treatments as part of Universal Health Care. In low-middle income countries, the capacity to prepare cost utility models may be limited and using existing validated models is a practical solution to assist decision making. This study uses a cost utility model developed and independently validated for the United Kingdom, and adapts it to Philippines, Egypt, Morocco and Vietnam. The model evaluates the clinical benefit and economic impact of using racecadotril in addition to rehydration solution to treat diarrhoea in children. The results show that racecadotril is cost-saving and improves the quality of life for children in Philippines, Egypt, Morocco and Vietnam.


Assuntos
Antidiarreicos , Países em Desenvolvimento , Diarreia , Soluções para Reidratação , Tiorfano , Antidiarreicos/economia , Antidiarreicos/uso terapêutico , Criança , Pré-Escolar , Diarreia/tratamento farmacológico , Diarreia/economia , Egito/epidemiologia , Hidratação , Humanos , Lactente , Marrocos , Filipinas , Soluções para Reidratação/economia , Soluções para Reidratação/uso terapêutico , Tiorfano/análogos & derivados , Tiorfano/economia , Tiorfano/uso terapêutico , Vietnã
17.
Nat Commun ; 13(1): 906, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35173153

RESUMO

Monolayers of two-dimensional van der Waals materials exhibit novel electronic phases distinct from their bulk due to the symmetry breaking and reduced screening in the absence of the interlayer coupling. In this work, we combine angle-resolved photoemission spectroscopy and scanning tunneling microscopy/spectroscopy to demonstrate the emergence of a unique insulating 2 × 1 dimer ground state in monolayer 1T-IrTe2 that has a large band gap in contrast to the metallic bilayer-to-bulk forms of this material. First-principles calculations reveal that phonon and charge instabilities as well as local bond formation collectively enhance and stabilize a charge-ordered ground state. Our findings provide important insights into the subtle balance of interactions having similar energy scales that occurs in the absence of strong interlayer coupling, which offers new opportunities to engineer the properties of 2D monolayers.

18.
Small ; 18(9): e2106053, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35038218

RESUMO

Interlayer coupling between individual unit layers is known to be critical in manipulating the layer-dependent properties of two-dimensional (2D) materials. While recent studies have revealed that several 2D materials with significant degrees of interlayer interaction (such as black phosphorus) show strongly layer-dependent properties, the origin based on the electronic structure is drawing intensive attention along with 2D materials exploration. Here, the direct observation of a highly dispersive single electronic band along the interlayer direction in puckered 2D PdSe2 as an experimental hallmark of strong interlayer couplings is reported. Remarkably large band dispersion along the kz -direction near Fermi level, which is even wider than the in-plane one, is observed by the angle-resolved photoemission spectroscopy measurement. Employing X-ray absorption spectroscopy and density functional theory calculations, it is revealed that the strong interlayer coupling in 2D PdSe2 originates from the unique directional bonding of Pd d orbitals associated with unexpected Pd 4d9 configuration, which consequently plays a decisive role for the strong layer-dependency of the band gap.

19.
J Phys Condens Matter ; 34(27)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35073534

RESUMO

First-principles band structure theory on the basis of the density functional theory (DFT) plays an essential role in the investigation of topological properties of weakly-correlated systems. DFT band structures show clear bulk band crossings for Weyl and Dirac semimetals, and surface band crossings for topological insulators and topological-crystalline insulators. In contrast, for strongly-correlatedf-electron systems, their topological properties are relatively less explored because the simple DFT does not work properly in describing the electronic structures of strongly-correlatedfelectrons. In this perspective, we examine the band theoretical approaches to topological properties of strongly-correlatedf-electron Kondo systems. We recapitulate current status of understanding of electronic structures and topological properties of strongly-correlated 4f-electron systems, such as Ce, SmB6, and g-SmS, and also a 5f-electron system PuB4, the electronic structures of which were investigated by the DFT combined with the dynamical mean-field theory (DFT + DMFT). Finally, we provide future directions and perspectives of improving theoretical band approaches to search for new topologicalf-electron systems, as an outlook.

20.
Pers Soc Psychol Bull ; 48(12): 1651-1666, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34657498

RESUMO

Power has long been associated with dishonesty. Here, we examined the contributions of personal and structural factors associated with power. Across five studies (N = 1,366), we tested the hypothesis that being dominant, more than having power and felt prestige, predicts dishonesty in incentivized tasks, moral disengagement, and breaking of Covid-19 containment rules. Dominance and dishonesty were positively associated (Study 1). Furthermore, dominance contributed to the positive relationship between occupational power and dishonesty in natural settings (Studies 2 and 5). Different types of power had inconsistent effects on dishonesty (Studies 3 and 4). Prestige was unrelated to dishonesty. Dominant individuals were overrepresented at the top, suggesting that the association between power and dishonesty may derive from self-selection processes, rather than power itself.


Assuntos
COVID-19 , Humanos , Enganação , Princípios Morais , Poder Psicológico , Emoções
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