Dithiocarbonate‐based non‐hygroscopic polymers with a glass transition temperature (Tg) and polydispersity index (PDI) of ≈4 °C and 1, respectively, are synthesized through living cationic ...ring‐opening polymerization. These liquid‐state polymers are characterized by monodispersity based on the low Tg and PDI, rendering remarkable miscibility with the perovskite precursors without aggregation. Accordingly, these polymers are added to perovskite solar cells (PSCs) to enhance their power conversion efficiency (PCE). The PCE of reference PSCs increases from 19.70% to 23.52% after direct addition of the synthesized polymer. This efficiency improvement is attributed to the considerable increases in short‐circuit current density (JSC) and fill factor (FF), resulting from the augmented size and defect passivation of perovskite crystals induced by added polymers. In fact, the PCE and JSC of the devices measured in the laboratory and the certification center are the highest among the reported polymer‐added PSCs, thanks to the great miscibility of the new polymers leading to the large amount addition which enables more thorough passivation among the grain boundaries. The improvement in open‐circuit voltage falls short as compared to that in JSC and FF, ascribed to the relatively moderate interaction strength between perovskite materials and dithiocarbonate groups.
Liquid‐state dithiocarbonate‐based polymers with monodispersity render exceptionally high performance when used as additives for perovskite solar cells. The dithiocarbonate‐based polymers are synthesized by connecting five‐membered cyclic dithiocarbonates through the living cationic ring opening polymerization. The resulting devices exhibit efficiencies of 23.5% and 22.0% during the laboratory and certified measurement, respectively, which are the highest among the perovskite solar cells containing polymers.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Topotactic phase transformation enables structural transition without losing the crystalline symmetry of the parental phase and provides an effective platform for elucidating the redox reaction and ...oxygen diffusion within transition metal oxides. In addition, it enables tuning of the emergent physical properties of complex oxides, through strong interaction between the lattice and electronic degrees of freedom. In this communication, the electronic structure evolution of SrFeOx epitaxial thin films is identified in real‐time, during the progress of reversible topotactic phase transformation. Using real‐time optical spectroscopy, the phase transition between the two structurally distinct phases (i.e., brownmillerite and perovskite) is quantitatively monitored, and a pressure–temperature phase diagram of the topotactic transformation is constructed for the first time. The transformation at relatively low temperatures is attributed to a markedly small difference in Gibbs free energy compared to the known similar class of materials to date. This study highlights the phase stability and reversibility of SrFeOx thin films, which is highly relevant for energy and environmental applications exploiting the redox reactions.
Topotactic phase transformation coupled with the metal–insulator transition in SrFeOx epitaxial thin films is studied using real‐time optical spectroscopy. The oxygen‐content‐dependent phase transition leads to a pressure–temperature phase diagram of the topotactic transformation. The transformation at relatively low temperatures is ascribed to a markedly small Gibbs' free energy difference between the two structurally distinctive phases.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Perovskite solar cells (PSCs) are considered to be one of the most promising solar energy harvesters owing to their high power conversion efficiency (PCE). To increase their PCE even further, ...additives are used; however, some of these additives pose certain disadvantages, which limit their applications to PSCs. Therefore, in this study, the nature‐inspired ecofriendly M13 bacteriophage is genetically engineered to maximize its performance as a perovskite crystal growth template and as a passivator for PSCs. The genetic manipulation of the M13 bacteriophage enhances the Lewis coordination between the perovskite materials and single‐stranded virus by amplifying a designated amino acid group. Among the 20 types of amino acids, lysine (Lys or K), arginine (Arg or R), and methionine (Aug or M) exhibit the strongest interaction with the perovskite materials. Results suggest that the K‐amplified genetically engineered M13 bacteriophage is the most effective. The K‐type M13 virus‐inoculated PSCs yield a PCE of 23.6% in the laboratory. This device, when taken to a national laboratory for verification, exhibits a certified forward and reverse bias‐combined efficiency (22.3%), which, to the best of the authors’ knowledge, is one of the highest efficiencies reported among the biomaterial‐based PSCs.
Genetic modification of M13 bacteriophages amplifies amino acid K, which functions as a perovskite growth template and a stronger passivator than the wild‐type virus in PSCs. The modified virus‐added PSCs exhibit a higher PCE (23.6%) than wild‐type M13 virus‐added devices (22.8%). The observed enhancement is attributed to slightly larger perovskite grains, stronger grain boundary passivation, and improved hole conductivity.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
To evaluate the performance of the Academia-Government Collaboration for Laboratory Medicine Standardization in Korea (KR-STDZN) based on data from KR-STDZN proficiency testing (KR-STDZN-PT) for ...creatinine over eight years (2015-2022).
We used KR-STDZN-PT data of creatinine tests from 2015 to 2022. Acceptance of the participating institutions' test results was assessed by calculating the acceptance performance as absolute bias (absBias%), total coefficient of variance (tCV%), and total error (TE%) for each sample using six measurements from each institution and true values of each reference material. The test result was considered acceptable when absBias%, tCV%, and TE% were <5.10, <3.20, and <11.40 %, respectively. The proportion of acceptable institutions among all participating institutions in each round was defined as the acceptance rate. Improvements in absBias%, tCV%, and TE% were analyzed using creatinine concentration ranges in samples.
The number of participating institutions increased from 2015 to 2017 but remained consistent since 2018. The acceptance rates for absBias% and TE% increased from 52.2 and 77.6 %, in 2015 and to 90.7 and 96.3 %, in 2022, respectively. The acceptance rate for tCV% remained in the 90 % range for eight years. When creatinine <3 mg/dL, mean absBias%, and mean TE% improved significantly in 2021-2022 compared to 2015-2016 (p<0.05). When creatinine >3 mg/dL, acceptance performance did not improve. Mean tCV% remained consistent annually regardless of creatinine concentration. No significant variations in test methods were observed.
The collaboration between academia and the government improved creatinine testing quality. Nevertheless, KR-STDZN must be expanded and refined.
Summary
In this prospective study, serum levels of 12 possible biomarkers were compared between osteonecrosis of the jaw (ONJ) and control groups, before and after dentoalveolar surgery. The results ...suggest that patients with abnormal serum levels of specific biomarkers should be monitored closely for the prevention and early diagnosis of ONJ.
Introduction
Bisphosphonate-related osteonecrosis of the jaw (ONJ) is an adverse effect of long-term bisphosphonate therapy. This study aimed to identify bone biomarkers for ONJ risk assessment and diagnosis.
Methods
This prospective study included patients with histories of bisphosphonate therapy without current ONJ who were in need of dentoalveolar surgery of the jaw area. Serum levels of 12 possible bone markers, selected based on their involvement in ONJ pathogenesis, were compared between ONJ and control groups before dentoalveolar surgery (T0), at 8 postoperative weeks (T1), and at 4 months after diagnosis(T2).
Results
Seventy-six patients who met the inclusion criteria were included in the study; 33 were assigned to the ONJ group, and 43 patients without ONJ signs or symptoms after dentoalveolar surgery were assigned to the control group. In the ONJ group, at both T0 and T1, the mean tartrate-resistant acid phosphatase isoform 5b (TRACP 5b) levels were significantly lower and the mean Dickkopf-related protein 1 (DKK1) levels were significantly higher than the corresponding values for the control group. Linear mixed model analysis revealed significant group effects over time for serum TRACP 5b and DKK1 after adjusting for demographic, pharmacological, and diagnostic variables. Lower serum levels of TRACP 5b under a specified cut-off value (≤ 2.899 U/L) at T0 indicated a 20.40-fold increased risk of ONJ development.
Conclusion
Patients with abnormally low serum levels of TRACP 5b and high serum levels of DKK1 should be monitored closely before and after dentoalveolar surgery for the prevention and early diagnosis of ONJ.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Ultraviolet (UV) radiation stimulates the expression of matrix metalloproteinases (MMPs) and inflammatory cytokines. These signaling pathways participate in the degradation of the extracellular ...matrix and induce inflammatory responses that lead to photoaging. This study evaluated the antioxidant activity and the effect on MMPs and procollagen of putgyul extract in vitro. The anti-photoaging activity of putgyul extracts was estimated in vivo using hairless mice (HR-1). The putgyul extracts reduced MMP-1 production and increased the content of procollagen type I carboxy-terminal peptide in human dermal fibroblasts. Ultravilot-B (UVB)-induced expression of inflammatory cytokines and MMPs was detected in mice, and putgyul extracts suppressed the expression. These results suggest that putgyul extract inhibits photoaging by inhibiting the expression of MMPs that degrade collagen and inhibiting cytokines that induce inflammatory responses. The mouse model also demonstrated that oral administration of putgyul extracts decreased wrinkle depth, epidermal thickness, collagen degradation, and trans-epidermal water loss, and increased β-glucosidase activity on UVB exposed skin. Putgyul extract protects against UVB-induced damage of skin and could be valuable in the prevention of photoaging.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Rice bran, a by-product derived from processing rice, is a rich source of bioactive compounds. Recent studies have suggested that the fermentation can improve their biological activities. This study ...aimed to determined the level of γ-oryzanol, β-glucan and total phenol contents of fermented rice bran from 21 Korean varieties, as well as to evaluate their antioxidant activities. We also assessed the validation of the analytical method for determining γ-oryzanol content in fermented rice brans. Among the fermented rice brans, the Haedam rice bran contained the highest level of total phenol content (156.08 mg gallic acid equivalents/g), DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity (71.30%) and ORAC (Oxygen radical absorbance capacity) value (1101.31 μM trolox equivalents/g). Furthermore, the fermented Migwang rice bran showed the highest level of γ-oryzanol content (294.77 ± 6.74 mg/100 g).
Lilium lancifolium is native to Northeast Asia and its bulbs have been used for medicinal treatment. Moreover, Japan has been using L. lancifolium bulbs more actively as food ingredients than Korea. ...Therefore, this study was to investigate the characteristics of Korean L. lancifolium bulbs, with respect to food component and functionality. As a result of proximate composition analysis, L. lancifolium bulbs have an abundant carbohydrate content. HPLC analysis indicated p‐coumaric acid and ferulic acid contents of Korean L. lancifolium extract were 1.14 ± 0.01, 1.46 ± 0.00 mg/g, but only p‐coumaric acid was less detected in Japanese extract. Also, Korean L. lancifolium bulbs extract exhibited significant antioxidant effects, as evaluated with antioxidant activity and compound, than Japanese extract. Furthermore, Korean L. lancifolium bulbs extract significantly inhibited pro‐inflammatory protein expressions through MyD88 dependent pathway. Therefore, these results suggested Korean L. lancifolium bulbs have the potential to being functional food ingredients.
Practical applications
Lilium lancifolium is a perennial plant belonging to the Liliaceae family. The storage organ of L. lancifolium is surrounded by several fleshy nodes at the base of the stem, called the bulb, which has been used as food or medicine to treat pneumonia and bronchitis. L. lancifolium is widely found in countries of Northeast Asia, such as Korea, Japan, and China, and its bulbs have been studied for presence of bioactive compounds that have important functional activities. The bioactive compounds in the L. lancifolium bulbs may vary from region to region. In this study, the difference observed in the contents of different bioactive compounds and the efficacy of anti‐inflammatory effects of L. lancifolium bulbs from different regions were consistent in this regard. As a comparative study of food materials by region, these L. lancifolium bulbs have the potential to be used as a food material for preventing inflammatory diseases.
Antioxidant and anti‐inflammatory effects of Lilium lancifolium bulbs extract
Wan‐Sup Sim, Sun‐Il Choi, Tae‐Dong Jung, Bong‐Yeon Cho, Seung‐Hyun Choi, Sung‐Min Park, Ok‐Hwan Lee
p‐Coumaric acid and ferulic acid contents of Korean L. lancifolium extract were higher than Japanese extract. Korean L. lancifolium bulbs extract exhibited significant antioxidant effects, compared to Japanese extract. Korean L. lancifolium bulbs extract significantly inhibited pro‐inflammatory protein expressions through MyD88 dependent pathway, compared to Japanese extract.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Chronic cerebral hypoperfusion is considered as a pivotal factor of cognitive impairment that occurs in cerebrovascular diseases. This study investigated the ameliorating effect of scutellarin (SCT) ...on spatial cognitive impairment and β-amyloid (Aβ) formation in rats with chronic cerebral hypoperfusion induced by permanent bilateral common carotid artery occlusion (pBCAO). SCT is a flavonoid in medicinal herb of Erigeron breviscapus (vant.) Hand. Mazz. known to have neuroprotective, antioxidative and anti-inflammatory effects. However, the beneficial effect and pivotal mechanism of SCT on cognitive impairment are still unclear. SCT was treated orally with two doses (10 or 30 mg/kg) for 4 weeks. Results of Morris water maze test performed on the ninth week after pBCAO revealed that SCT (30 mg/kg)-treated rats had significantly shortened escape latencies in acquisition training trials, significantly prolonged swimming time at the platform and its surrounding zone, significant increase in memory score, significant reduction in the number of target heading, and significant reduction in the time required for the first target heading during the retention trial compared to rats in the sham-control group. SCT significantly inhibited the production of A<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">β<mml:mo stretchy="false">(</mml:mo>1–40<mml:mo stretchy="false">)</mml:mo></mml:math> and A<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">β<mml:mo stretchy="false">(</mml:mo>1–42<mml:mo stretchy="false">)</mml:mo></mml:math> in brain tissues. However, SCT significantly upregulated the expression levels of amyloid precursor protein and β-site APP-converting enzyme-1 in the hippocampus. In addition, SCT significantly inhibited the activation of Iba1-expressing microglia in brain tissues. The results suggest that SCT can exert ameliorating effect on spatial cognitive impairment caused by chronic cerebral hypoperfusion through suppressing Aβ formation and microglial activation in brain tissues. Therefore, SCT can be used as a beneficial drug for vascular dementia and Alzheimer's disease.
Antioxidants are used to prevent the oxidation of foods. When used for food additive purposes, the dosage should be regulated and the functionality evaluated to ensure stability. In this study, we ...performed a method validation for the quantitative analysis of rosemary extract residues and evaluated the antioxidant activity of rosemary extract in food matrices. The validated method was able to determine rosemary extract under the optimized high-performance liquid chromatography-photodiode array (HPLC-PDA) conditions. Furthermore, the antioxidant activity was evaluated by peroxide value, acid value, and in terms of the residual antioxidant levels in lard oil. For HPLC-PDA analysis, the limit of detection and quantification of rosemary extracts was ranged from 0.22 to 1.73 μg/mL, 0.66 to 5.23 μg/mL and the recoveries of the rosemary extracts ranged from 70.6 to 114.0%, with relative standard deviations of between 0.2% and 3.8%. In terms of antioxidant activity, carnosic acid performed better than carnosol. Furthermore, by evaluation of the residual antioxidant level using HPLC, we found that carnosic acid is more stable in lard oil than carnosol. These results indicate that rosemary extract can be used as an antioxidant and that the analytical method is suitable for the determination of rosemary extract in various food samples.
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