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1.
Phys Rev Lett ; 132(22): 226401, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38877910

ABSTRACT

1T-transition metal dichalcogenides (TMDs) have been an exciting platform for exploring the intertwinement of charge density waves and strong correlation phenomena. While the David star structure has been conventionally considered as the underlying charge order in the literature, recent scanning tunneling probe experiments on several monolayer 1T-TMD materials have motivated a new, alternative structure, namely, the anion-centered David star structure. In this Letter, we show that this novel anion-centered David star structure manifestly breaks inversion symmetry, resulting in flat bands with pronounced Rashba spin-orbit couplings. These distinctive features unlock novel possibilities and functionalities for 1T-TMDs, including the giant spin Hall effect, the emergence of Chern bands, and spin liquid that spontaneously breaks crystalline rotational symmetry. Our findings establish promising avenues for exploring emerging quantum phenomena of monolayer 1T-TMDs with this novel noncentrosymmetric structure.

2.
Methods Enzymol ; 694: 109-135, 2024.
Article in English | MEDLINE | ID: mdl-38492948

ABSTRACT

In neuroscience, understanding the mechanics of synapses, especially the function of force-sensitive proteins at the molecular level, is essential. This need emphasizes the importance of precise measurement of synaptic protein interactions. Addressing this, we introduce high-resolution magnetic tweezers (MT) as a novel method to probe the mechanics of synapse-related proteins with high precision. We demonstrate this technique through studying SNARE-complexin interactions, crucial for synaptic transmission, showcasing its capability to apply specific forces to individual molecules. Our results reveal that high-resolution MT provides in-depth insights into the stability and dynamic transitions of synaptic protein complexes. This method is a significant advancement in synapse biology, offering a new tool for researchers to investigate the impact of mechanical forces on synaptic functions and their implications for neurological disorders.


Subject(s)
SNARE Proteins , Synapses , SNARE Proteins/metabolism , Synaptic Transmission , Magnetic Phenomena , Adaptor Proteins, Vesicular Transport/metabolism
4.
Sci Rep ; 13(1): 12445, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37528106

ABSTRACT

Identifying the magnetic state of materials is of great interest in a wide range of applications, but direct identification is not always straightforward due to limitations in neutron scattering experiments. In this work, we present a machine-learning approach using decision-tree algorithms to identify magnetism from the spin-integrated excitation spectrum, such as the density of states. The dataset was generated by Hartree-Fock mean-field calculations of candidate antiferromagnetic orders on a Wannier Hamiltonian, extracted from first-principle calculations targeting BaOsO[Formula: see text]. Our machine learning model was trained using various types of spectral data, including local density of states, momentum-resolved density of states at high-symmetry points, and the lowest excitation energies from the Fermi level. Although the density of states shows good performance for machine learning, the broadening method had a significant impact on the model's performance. We improved the model's performance by designing the excitation energy as a feature for machine learning, resulting in excellent classification of antiferromagnetic order, even for test samples generated by different methods from the training samples used for machine learning.

6.
Adv Mater ; 35(15): e2208833, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36739615

ABSTRACT

Interfaces between dissimilar correlated oxides can offer devices with versatile functionalities, and great efforts have been made to manipulate interfacial electronic phases. However, realizing such phases is often hampered by the inability to directly access the electronic structure information; most correlated interfacial phenomena appear within a few atomic layers from the interface. Here, atomic-scale epitaxy and photoemission spectroscopy are utilized to realize the interface control of correlated electronic phases in atomic-scale ruthenate-titanate heterostructures. While bulk SrRuO3 is a ferromagnetic metal, the heterointerfaces exclusively generate three distinct correlated phases in the single-atomic-layer limit. The theoretical analysis reveals that atomic-scale structural proximity effects yield Fermi liquid, Hund metal, and Mott insulator phases in the quantum-confined SrRuO3 . These results highlight the extensive interfacial tunability of electronic phases, hitherto hidden in the atomically thin correlated heterostructure. Moreover, this experimental platform suggests a way to control interfacial electronic phases of various correlated materials.

7.
Medicina (Kaunas) ; 59(1)2023 Jan 11.
Article in English | MEDLINE | ID: mdl-36676768

ABSTRACT

Background and objectives: As is well known, cancer patients require extensive medical attention as they undergo surgery, chemotherapy, radiotherapy, and supportive care. The importance of high-quality cancer-directed nursing, combined with precision medicine, to maximize their survival outcomes and help them achieve a better quality of life cannot be overemphasized. In this context, we offered a new cancer-oriented comprehensive nursing system to our inpatients and reviewed its clinical outcomes in comparison with those from the preexisting general cancer ward. Materials and Methods: From March 2019 to February 2020, a total of 102 cancer patients and 42 nurses were enrolled in this pilot study. We aimed to analyze their performance in three main categories: structure, process, and patient/nurse outcomes. Results: First, structural (nurse staffing and environment) upgrades were installed in the cancer-oriented comprehensive nursing ward, including an improved nurse-patient ratio (1:8 in the comprehensive ward as compared with 1:14 in the general ward), wider space between beds (1.5 m versus 1.0 m), fully automatic beds with fall prevention sensors, etc. Second, the nursing process was improved (missed care 0.1 event/month vs. 1.3 event/month). Third, both patient and nurse outcomes showed preferable results in the comprehensive ward. The patient satisfaction level was higher in the comprehensive nursing ward than in the general ward (willing to revisit: 91.7% and 78.4%, respectively; willing to recommend to others: 95.0% and 76.8%, respectively). Pressure ulcers, as a patient safety indicator, were also decreased (0.3 events/month vs. 0.8 events/month). However, the fall incidence was similar in both groups (1.6 events/month vs. 1.5 events/month). In terms of nurse outcomes, turnover intention was stabilized and nurses' job satisfaction in the comprehensive ward was superior to that of their counterparts. Conclusions: Our study was a pilot study to demonstrate that cancer patient-oriented comprehensive nursing services can be helpful in improving the quality of cancer treatment and nurses' job satisfaction. Continued interest in and efforts to improve nursing care delivery are also crucial in achieving and maintaining the best possible cancer patient care.


Subject(s)
Neoplasms , Oncologists , Humans , Pilot Projects , Quality of Life , Patient Satisfaction , Republic of Korea , Surveys and Questionnaires , Neoplasms/therapy
8.
Matern Child Nutr ; 18(4): e13378, 2022 10.
Article in English | MEDLINE | ID: mdl-35726357

ABSTRACT

Investments in social assistance programmes (SAPs) have accelerated alongside interest in using SAPs to improve health and nutrition outcomes. However, evidence of how design features within and across programme types influence the effectiveness of SAPs for improving diet and nutrition outcomes among women and children is limited. To address this, we reviewed evaluations of cash, in-kind and voucher programmes conducted between 2010 and 2020 among women and children, and examined associations between design features (targeting, including household and individual transfers, fortified foods and behaviour change communication) and positive impacts on diet (diet diversity, micronutrient intake) and nutrition (anthropometric indicators, haemoglobin, anaemia) outcomes. Our review has several key findings. First, SAPs improve dietary diversity and intake of micronutrient-rich foods among women and children, as well as improve several nutrition outcomes. Second, SAPs were more likely to impact diet and nutrition outcomes among women compared with children (23/45 [51%] vs. 52/144 [36%] of outcomes measured). Third, in-kind (all but one of which included fortified foods) compared with cash transfer programmes were more likely to significantly increase women's body mass index and children's weight-for-height/length Z-score, and both women's and children's haemoglobin and anaemia. However, there is limited evidence on the effectiveness of SAPs for improving micronutrient status and preventing increased prevalence of overweight and obesity for all populations and for improving diet and nutrition outcomes among men, adolescents and the elderly. Further research in these areas is urgently needed to optimize impact of SAPs on diet and nutrition outcomes as countries increase investments in SAPs.


Subject(s)
Anemia , Nutritional Status , Adolescent , Aged , Child , Diet , Female , Food, Fortified , Humans , Male , Micronutrients
9.
J Glob Health ; 12: 08001, 2022.
Article in English | MEDLINE | ID: mdl-35198152

ABSTRACT

BACKGROUND: Low-quality diets contribute to the burden of malnutrition and increase the risk of children not achieving their developmental potential. Nutrition-sensitive agriculture programs address the underlying determinants of malnutrition, though their contributions to improving diets do not factor into current nutrition impact modeling tools. OBJECTIVE: To synthesize the evidence on the effectiveness of nutrition-sensitive agriculture programs in improving dietary diversity in young children (6-23.9 months and 6-60 months). METHODS: A literature search was conducted for published trials through existing systematic reviews and individual database search of the ISI Web of Science. All dietary diversity measures in the studies selected to be in the analysis were extracted. Estimation of main pooled effects were conducted on outcomes of minimum diet diversity (MDD) and diet diversity score (DDS) using random-effects meta-regression models. We report pooled effect sizes as standardized mean differences (SMDs) or odds ratios (ORs). RESULTS: Nutrition-sensitive agricultural interventions have a significant positive impact on the diet diversity scores of children aged 6-23.9 months (SMD = 0.22, 95% confidence interval (CI) = 0.09-0.36) and on the odds of reaching minimum diet diversity (OR = 1.45, 95% CI = 1.20, 1.76). Similar impacts are found when analyses are expanded to include studies for children aged 6-60 months (DDS SMD = 0.22, 95% CI = 0.12-0.32) (MDD OR = 1.64, 95% CI: = 1.38-1.94). CONCLUSION: Nutrition-sensitive agriculture interventions consistently have a positive impact on child dietary diversity. Incorporating this evidence in nutrition modeling tools can contribute to decision-making on the relative benefits of nutrition-sensitive interventions as compared with other maternal, newborn, child health and nutrition (MNCHN) interventions.


Subject(s)
Diet , Malnutrition , Agriculture , Child , Child, Preschool , Humans , Infant , Infant, Newborn , Nutritional Status
10.
Nat Commun ; 13(1): 323, 2022 Jan 14.
Article in English | MEDLINE | ID: mdl-35031621

ABSTRACT

Quantum spin liquids realize massive entanglement and fractional quasiparticles from localized spins, proposed as an avenue for quantum science and technology. In particular, topological quantum computations are suggested in the non-abelian phase of Kitaev quantum spin liquid with Majorana fermions, and detection of Majorana fermions is one of the most outstanding problems in modern condensed matter physics. Here, we propose a concrete way to identify the non-abelian Kitaev quantum spin liquid by magnetic field angle dependence. Topologically protected critical lines exist on a plane of magnetic field angles, and their shapes are determined by microscopic spin interactions. A chirality operator plays a key role in demonstrating microscopic dependences of the critical lines. We also show that the chirality operator can be used to evaluate topological properties of the non-abelian Kitaev quantum spin liquid without relying on Majorana fermion descriptions. Experimental criteria for the non-abelian spin liquid state are provided for future experiments.

11.
Antioxidants (Basel) ; 9(10)2020 Oct 07.
Article in English | MEDLINE | ID: mdl-33036328

ABSTRACT

Infertility, a couple's inability to conceive after one year of unprotected regular intercourse, is an important issue in the world. The use of natural products in the treatment of infertility has been considered as a possible alternative to conventional therapies. The present study aimed to investigate the effects and the mechanisms of various natural products on infertility. We collected articles regarding infertility and natural products using the research databases PubMed and Google Scholar. Several natural products possess antioxidant properties and androgenic activities on productive factors and hormones. Antioxidants are the first defense barrier against free radicals produced by oxidative stress (OS). They remove reactive oxygen stress (ROS), reducing insulin resistance, total cholesterol, fat accumulation, and cancer growth. Moreover, various natural products increase endometrial receptivity and fertility ability showing androgenic activities on productive factors and hormones. For example, Angelica keiskei powder and Astragalus mongholicus extract showed anti-infertility efficacies in males and females, respectively. On the other hand, adverse effects and acute toxicity of natural products were also reported. Tripterygium glycoside decreased fertility ability both in males and females. Results indicate that management of infertility with natural products could be beneficial with further clinical trials to evaluate the safety and effect.

12.
Phys Rev Lett ; 125(9): 096403, 2020 Aug 28.
Article in English | MEDLINE | ID: mdl-32915631

ABSTRACT

Effects of electron many-body interactions amplify in an electronic system with a narrow bandwidth opening a way to exotic physics. A narrow band in a two-dimensional (2D) honeycomb lattice is particularly intriguing as combined with Dirac bands and topological properties but the material realization of a strongly interacting honeycomb lattice described by the Kane-Mele-Hubbard model has not been identified. Here we report a novel approach to realize a 2D honeycomb-lattice narrow-band system with strongly interacting 5d electrons. We engineer a well-known triangular lattice 2D Mott insulator 1T-TaS_{2} into a honeycomb lattice utilizing an adsorbate superstructure. Potassium (K) adatoms at an optimum coverage deplete one-third of the unpaired d electrons and the remaining electrons form a honeycomb lattice with a very small hopping. Ab initio calculations show extremely narrow Z_{2} topological bands mimicking the Kane-Mele model. Electron spectroscopy detects an order of magnitude bigger charge gap confirming the substantial electron correlation as confirmed by dynamical mean field theory. It could be the first artificial Mott insulator with a finite spin Chern number.

13.
Food Nutr Bull ; 41(1): 18-37, 2020 03.
Article in English | MEDLINE | ID: mdl-31542962

ABSTRACT

BACKGROUND: Nutrition-sensitive programs can accelerate progress in addressing malnutrition. However, evidence gaps exist related to their effectiveness and how to optimize program design and implementation. OBJECTIVE: We present the process the International Food Policy Research Institute and the World Food Programme (WFP) used to develop nutrition-sensitive program guidance and plans for improving program effectiveness and contributing to the evidence base through rigorous evaluations. METHODS: A 5-step process, using principles of design thinking (a systematic, iterative analytical approach to problem solving), was used to develop, test, and refine WFP's nutrition-sensitive guidance. The guidance focuses on improving nutrition outcomes for nutritionally vulnerable groups across the life cycle: women and children in the first 1000 days, preschoolers, schoolchildren, and adolescents. RESULTS: Through iterative consultations, we created WFP's nutrition-sensitive guidance that includes harmonized theories of change across WFP's programs; 7 opportunities to enhance the programs' nutrition-sensitivity; and mapping of these opportunities to WFP programs and key evidence gaps. This guidance has been rolled out to WFP's offices worldwide to support improved nutrition outcomes. Finally, several evaluation designs have been proposed to fill identified evidence gaps. CONCLUSIONS: By leveraging our implementation-research partnership, we expect that WFP's programs will be more effective and cost effective for improving nutrition. This can be assessed through coupling newly designed nutrition-sensitive programs with rigorous evaluations. Evaluation results will be used to refine WFP's nutrition-sensitive guidance and improve their programs globally. This guidance, and creation process, could be useful for others interested in designing nutrition-sensitive programs and increasing program effectiveness for nutrition.


Subject(s)
Implementation Science , International Cooperation , Malnutrition , Program Evaluation/methods , Transtheoretical Model , Adolescent , Adult , Child , Child, Preschool , Female , Global Health , Humans , Infant , Infant, Newborn , Male , Middle Aged , Nutrition Policy , Young Adult
14.
Phys Rev Lett ; 122(14): 147203, 2019 Apr 12.
Article in English | MEDLINE | ID: mdl-31050444

ABSTRACT

We investigate signatures of topological quantum phase transitions (TQPTs) between the Z_{2} quantum spin liquids (QSLs). In two spatial dimensions, Z_{2} QSLs and their TQPTs are only well defined at zero temperature (T=0), and it is imperative to clarify their observable signatures under nonzero temperatures. Here, we present the vestiges of TQPTs between Z_{2} QSLs with Majorana fermions in terms of thermal Hall conductivity κ_{xy} at nonzero temperatures. The κ_{xy}/T shows characteristic temperature dependences around TQPTs. We argue that an exponential upturn near T=0 and the peak of κ_{xy}/T around massive excitation energy are observable smoking-gun signals of the TQPTs. Quantum critical fan-shape temperature dependences are uncovered across TQPTs. We also perform the parton mean-field analysis on a modified Kitaev model with next-nearest neighbor interactions finding TQPTs between the phases with different Chern numbers and their vestiges self-consistently. We discuss the implication of our results to the recent experiments in α-RuCl_{3}.

15.
Eur J Med Chem ; 166: 65-74, 2019 Mar 15.
Article in English | MEDLINE | ID: mdl-30684871

ABSTRACT

Immunomodulatory drugs (IMiDs) exert anti-myeloma activity by binding to the protein cereblon (CRBN) and subsequently degrading IKZF1/3. Recently, their ability to recruit E3 ubiquitin ligase has been used in the proteolysis targeting chimera (PROTAC) technology. Herein, we design and synthesize a novel IMiD analog TD-106 that induces the degradation of IKZF1/3 and inhibits the proliferation of multiple myeloma cells in vitro as well as in vivo. Moreover, we demonstrate that TD-428, which comprises TD-106 linked to a BET inhibitor, JQ1 efficiently induce BET protein degradation in the prostate cancer cell line 22Rv1. Consequently, cell proliferation is inhibited due to suppressed C-MYC transcription. These results, therefore, firmly suggest that the newly synthesized IMiD analog, TD-106, is a novel CRBN modulator that can be used for targeted protein degradation.


Subject(s)
Immunologic Factors/pharmacology , Peptide Hydrolases/metabolism , Proteolysis/drug effects , Adaptor Proteins, Signal Transducing , Animals , Cell Line, Tumor , Female , Humans , Immunologic Factors/chemical synthesis , Immunologic Factors/chemistry , Mice , Piperidones/chemical synthesis , Piperidones/chemistry , Piperidones/pharmacology , Ubiquitin-Protein Ligases , Xenograft Model Antitumor Assays
16.
Phys Rev Lett ; 114(1): 016402, 2015 Jan 09.
Article in English | MEDLINE | ID: mdl-25615484

ABSTRACT

A recently proposed configuration-interaction-based impurity solver is used in combination with the single-site and four-site cluster dynamical mean field approximations to investigate the three-band copper oxide model believed to describe the electronic structure of high transition temperature copper-oxide superconductors. Use of the configuration interaction solver enables verification of the convergence of results with respect to the number of bath orbitals. The spatial correlations included in the cluster approximation substantially shift the metal-insulator phase boundary relative to the prediction of the single-site approximation and increase the predicted energy gap of the insulating phase by about 1 eV above the single-site result. Vertex corrections occurring in the four-site approximation act to dramatically increase the value of the optical conductivity near the gap edge, resulting in better agreement with the data. The calculations reveal two distinct correlated insulating states: the "magnetically correlated insulator," in which nontrivial intersite correlations play an essential role in stabilizing the insulating state, and the strongly correlated insulator, in which local physics suffices. Comparison of the calculations to the data places the cuprates in the magnetically correlated Mott insulator regime.

17.
J Biomed Mater Res A ; 102(10): 3609-17, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24248774

ABSTRACT

The current study was designed to investigate the chemical and physical properties of porcine-derived xenografts of different crystallinity (low and high) and to evaluate their osteogenic potential. Porcine femur bone underwent a heat treatment process at 400°C (P400) and 1200°C (P1200) and was then milled into particles of 1 mm or less. In X-ray diffraction, P400 exhibited a low crystallinity compared with that of P1200, as indicated by the relatively wide diffraction peaks. Brunauer-Emmett-Teller analysis revealed that P400 also had a wider surface area than P1200. In micro-CT scan analysis of specimens in a rat calvarial defect model, bone mineral density of the P400 group was significantly higher than that of the P1200 group (p < 0.01). New bone formation was also remarkably higher at 8 weeks in the P400 group, which showed more new osteocytes in the lacuna compared with the P1200 group. In this study, low crystalline bone particles were obtained at low processing temperature (at temperature of 400°C) and achieved superior new bone formation compared with the high crystalline bone particles created at a higher process temperature (1200°C). It can be concluded that lower process temperature bone particles might provide a more effective graft material for enhancing bone formation. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3609-3617, 2014.


Subject(s)
Cold Temperature , Femur/chemistry , Osteogenesis , Skull/pathology , Animals , Bone Density , Bone Regeneration , Calcium/analysis , Disease Models, Animal , Femur/transplantation , Imaging, Three-Dimensional , Male , Phosphates/analysis , Porosity , Rats, Sprague-Dawley , Skull/diagnostic imaging , Sus scrofa , X-Ray Diffraction , X-Ray Microtomography
18.
Enzyme Microb Technol ; 53(3): 154-8, 2013 Aug 15.
Article in English | MEDLINE | ID: mdl-23830455

ABSTRACT

The enzymatic coproduction of biodiesel and glycerol carbonate by transesterification of soybean oil and dimethyl carbonate (DMC) has been studied in a solvent-free system. The effects on biodiesel and glycerol carbonate conversion of reaction conditions including the kind of enzyme, the amount of enzyme, the molar ratio of DMC to soybean oil, the reaction temperature, and water addition were investigated. The optimal conditions for biodiesel and glycerol carbonate were 20% Novozym 435, 10:1 molar ratio of DMC to soybean oil, and 0.7% water addition. Under these conditions, the conversions of 96.4% biodiesel and 92.1% glycerol carbonate have been achieved after 48h.


Subject(s)
Biofuels , Glycerol/analogs & derivatives , Soybean Oil/metabolism , Biotechnology , Carbonates/metabolism , Enzymes, Immobilized , Esterification , Formates , Fungal Proteins , Glycerol/metabolism , Lipase , Solvents , Temperature , Water
19.
Phys Rev Lett ; 109(6): 066401, 2012 Aug 10.
Article in English | MEDLINE | ID: mdl-23006286

ABSTRACT

Topological phases of quantum matter defy characterization by conventional order parameters but can exhibit a quantized electromagnetic response and/or protected surface states. We examine such phenomena in a model for three-dimensional correlated complex oxides, the pyrochlore iridates. The model realizes interacting topological insulators, with and without time-reversal symmetry, and topological Weyl semimetals. We use cellular dynamical mean-field theory, a method that incorporates quantum many-body effects and allows us to evaluate the magnetoelectric topological response coefficient in correlated systems. This invariant is used to unravel the presence of an interacting axion insulator absent within a simple mean-field study. We corroborate our bulk results by studying the evolution of the topological boundary states in the presence of interactions. Consequences for experiments and for the search for correlated materials with symmetry-protected topological order are given.

20.
J Ginseng Res ; 35(3): 360-7, 2011 Sep.
Article in English | MEDLINE | ID: mdl-23717081

ABSTRACT

In this study, we investigated the effects of total ginseng saponin (TGS) on the cutaneous wound healing process using histological analysis. A total of 24 ICR mice, 5-weeks-old, were used for all in vivo experiments. Mice were divided into control and TGS-treated groups and four equidistant 1-cm full-thickness dorsal incisional wounds were created. The wounds were extracted at days 1, 3, 5, and 7 post-injury for histomorphometrical analysis including wound area and contracture measurements, keratinocyte migration rate, and calculation of infiltrating inflammatory cells. The results showed that the wound area was smaller and keratinocyte migration rate was higher in the TGS-treated group than that of the control group from days 3 to 7. Inflammatory cells in the TGS-treated group at days 1 and 3 were reduced compared to the control group. Wound contraction in the TGS-treated group was greater than in the control group on days 3 to 5, and collagen deposition in the TGS-treated group was higher than in the control group during wound healing. The results indicate a beneficial effect of TGS when used to treat skin wounds.

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