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Significant Reduction of Unequal Population Exposure to Climate Extremes by Achieving the Carbon Neutrality
No full textClimate extremes, such as hot temperature and heavy precipitation events, have devastating effects on human societies. As the planet gets warmer, they have become more intense and more frequent. To avoid irreversible damages from climate extremes, many countries have committed to achieving net-zero anthropogenic carbon emissions, or carbon neutrality, by the 2050s. Here, we quantify the impact of carbon neutrality on population exposure to climate extremes using multi-model projections from the Coupled Model Intercomparison Project Phase 6 (CMIP6) Shared Socioeconomic Pathway (SSP)1-1.9 and SSP3-7.0 scenarios. It is found that the increasing population exposure to hot-temperature and heavy-precipitation extremes under SSP3-7.0 scenario can be substantially reduced by 87%-98% in the late 21st century by achieving the carbon neutrality based on SSP1-1.9 scenario. The benefits of carbon neutrality are particularly pronounced in Africa and Asia. The potential benefits of carbon neutrality are also significant in North America, Europe, and Oceania, where a reduction in climate extremes is more than twice as important as population decline in reducing population exposure to climate extremes. These results provide important scientific support for ongoing efforts to achieve net-zero carbon emissions by the 2050s to reduce potential climate risk and its inequity across continents. To avoid irreversible damages from climate extremes in a warming climate, net-zero anthropogenic carbon emissions, or carbon neutrality, has been proposed. However, how much damages from climate extremes can be mitigated by achieving the carbon neutrality has not been quantitatively assessed. Here, we show that achieving carbon neutrality could lead to a significant and widespread reduction in population exposure to hot-temperature and heavy-precipitation extremes by 87%-98% in the late 21st century. The benefits of carbon neutrality are particularly large in Africa and Asia. Even in North America, Europe, and Oceania, where the developed countries are concentrated, population exposure to climate extremes is projected to decrease significantly, primarily due to reduced climate extremes with a minor contribution of population decline. This finding underscores the critical importance of ongoing efforts to achieve net-zero carbon emissions by the 2050s to reduce potential climate risk and its inequity across continents. By the 2050s, carbon neutrality reduces population exposure to climate extremes by 87%-98% compared to current global warming rates Africa and Asia are projected to experience the most dramatic reductions in population exposure to climate extremes by carbon neutrality In North America, Europe, and Oceania, climate extreme change plays a more important role in population exposure to climate extremesY
University Students Understanding of the Behavior of Light and Their Reasoning to the Particle-like Nature of Light in the Photoelectric Effect
No full textUniversity students understanding of the photoelectric effect is investigated through semi-structured interviews and a written questionnaire. For the purpose of our study, we distinguish between two kinds of reasoning: the construction of a photon model of light to explain the experimental results of the photoelectric effect and one interpreting the nature of light in the context of the photoelectric effect. It was found that many students only had an energy description for the interaction between light and an electron and did not further elaborate on the physical processes. Students also struggled to explain the experimental results using the concept of the photon. We also investigated students reasoning in linking the photoelectric effect and the particle-like nature of light. Students in the study believed that the effect refuted the classical model, yet, did not sufficiently link the effect to the particle-like nature of light. Furthermore, they did not well describe the particle-like properties of light revealed in the photoelectric effect. Their particle conceptions were not clearly related to the photons properties. Finally, we suggest the implications of this study on the future teaching of the photoelectric effect and how the work relates to previous studies in this area.N
Benzbromarone Induces Targeted Degradation of HSP47 Protein and Improves Hypertrophic Scar Formation
No full textFibrotic diseases are characterized by the abnormal accumulation of collagen in the extracellular matrix, leading to the functional impairment of various organs. In the skin, excessive collagen deposition manifests as hypertrophic scars and keloids, placing a substantial burden on patients and the healthcare system worldwide. HSP47 is essential for proper collagen assembly and contributes to fibrosis. However, identifying clinically applicable HSP47 inhibitors has been a major pharmaceutical challenge. In this study, we identified benzbromarone (BBR) as an HSP47 inhibitor for hypertrophic scarring treatment. BBR inhibited collagen production and secretion in fibroblasts from patients with keloid by binding to HSP47 and inhibiting the interaction between HSP47 and collagen. Interestingly, BBR not only inhibits HSP47 but also acts as a molecular glue degrader that promotes its proteasome-dependent degradation. Through these molecular mechanisms, BBR effectively reduced hypertrophic scarring in mini pigs and rats with burns and/or excisional skin damage. Thus, these findings suggest that BBR can be used to clinically treat hypertrophic scars and, more generally, fibrotic diseases.Y
Long-term ozone exposure and mortality in patients with chronic kidney disease: a large cohort study
No full textBackground: Epidemiologic studies on the effects of long-term exposure to ozone (O3) have shown inconclusive results. It is unclear whether to O3 has an effect on chronic kidney disease (CKD). We investigated the effects of O3 on mortality and renal outcome in CKD. Methods: We included 61,073 participants and applied Cox proportional hazards models to examine the effects of ozone on the risk of end-stage renal disease (ESRD) and mortality in a two-pollutants model adjusted for socioeconomic status. We calculated the concentration of ozone exposure one year before enrollment and used inverse distance weighting (IDW) for interpolation, where the exposure was evenly distributed. Results: In the single pollutant model, O3 was significantly associated with an increased risk of ESRD and all-cause mortality. Based on the O3 concentration from IDW interpolation, this moving O3 average was significantly associated with an increased risk of ESRD and all-cause mortality. In a two-pollutants model, even after we adjusted for other measured pollutants, nitrogen dioxide did not attenuate the result for O3. The hazard ratio (HR) value for the district-level assessment is 1.025 with a 95% confidence interval (CI) of 1.014–1.035, while for the point-level assessment, the HR value is 1.04 with a 95% CI of 1.035–1.045. The impact of ozone on ESRD, hazard ratio (HR) values are, 1.049(95%CI: 1.044–1.054) at the district unit and 1.04 (95%CI: 1.031–1.05) at the individual address of the exposure assessment. The ozone hazard ratio for all-cause mortality was 1.012 (95% confidence interval: 1.008–1.017) for administrative districts and 1.04 (95% confidence interval: 1.031–1.05) for individual addresses. Conclusions: This study suggests that long-term ambient O3 increases the risk of ESRD and mortality in CKD. The strategy to decrease O3 emissions will substantially benefit health and the environment.Y
Compliance with new drug use and the effect of discrepant drug susceptibility testing on MDR/RR-TB treatment
No full textBACKGROUND: Following the WHO???s announcement in 2018, the use of new drugs was recommended for all patients with multidrug-resistant TB (MDR-TB) in Korea. This study aimed to evaluate adherence to new anti-TB drug regimens and implementation of molecular drug susceptibility testing (mDST) in Korea.METHODS: Nationwide, 560 patients were reported as having MDR-TB in 2021. The implementation of mDST and new anti-TB drug use were analysed. The discrepancy between mDST and phenotypic DST (pDST) results and their implications on the use of new anti-TB drugs were also analysed. The use of novel anti-TB drugs has been approved by the National TB Expert Committee.RESULTS: The non-adherence rate in MDR-TB patients was 14.3%. The mDST implementation rate was 96.1%. Of the 459 patients who underwent both mDST and pDST, the discordance rate for rifampicin (RIF) resistance was 22.6% (n = 104), of which 72.1% (n = 75) were resistant on mDST but susceptible on pDST. The discrepancy in mDST and pDST results related to RIF resistance was found to be the main cause of non-adherence to new drug regimen.CONCLUSION: Comprehensive training on how to interpret conflicting results between mDST and pDST could enhance the utilisation of new drugs in the treatment of MDR/RIF-resistant TB.N
Long-term exposure to high perceived temperature and risk of mortality among patients with chronic kidney disease
No full textHealth risks due to climate change are emerging, particularly from high-temperature exposure. The perceived temperature is an equivalent temperature based on the complete heat budget model of the human body. Therefore, we aimed to analyze the effect of perceived temperature on overall mortality among patients with chronic kidney disease. In total, 32,870 patients with chronic kidney disease in Seoul participated in this retrospective study (2001–2018) at three medical centers. The perceived temperature during the summer season was calculated using meteorological factors, including the air temperature near the automated weather station, dew point temperature, wind velocity, and total cloud amount. We assessed the association between perceived temperature using Kriging spatial interpolation and mortality in patients with CKD in the time-varying Cox proportional hazards model that was adjusted for sex, age, body mass index, hypertension, diabetes mellitus, estimated glomerular filtration rate, smoking, alcohol consumption, and educational level. During the 6.14 ± 3.96 years of follow-up, 3863 deaths were recorded. In multivariable analysis, the average level of perceived temperature and maximum level of perceived temperature demonstrated an increased risk of overall mortality among patients with chronic kidney disease. The concordance index for mortality of perceived temperature was higher than temperature, discomfort index, and heat index. When stratified by age, diabetes mellitus, and estimated glomerular filtration rate, patients with chronic kidney disease with young age (age <65 years) showed higher hazard ratio for mortality (interaction P = 0.049). Moreover, the risk of death in the winter and spring seasons was more significant compared to that of the summer and autumn seasons. Therefore, long-term exposure to high perceived temperature during summer increases the risk of mortality among patients with chronic kidney disease.Y
Group I pharmaceuticals of IARC and associated cancer risks: systematic review and meta-analysis
No full textWe aimed to summarize the cancer risk among patients with indication of group I pharmaceuticals as stated in monographs presented by the International Agency for Research on Cancer working groups. Following the PRISMA guidelines, a comprehensive literature search was conducted using the PubMed database. Pharmaceuticals with few studies on cancer risk were identified in systematic reviews; those with two or more studies were subjected to meta-analysis. For the meta-analysis, a random-effects model was used to calculate the summary relative risks (SRRs) and 95% confidence intervals (95% CIs). Heterogeneity across studies was presented using the Higgins I square value from Cochrans Q test. Among the 12 group I pharmaceuticals selected, three involved a single study [etoposide, thiotepa, and mustargen + oncovin + procarbazine + prednisone (MOPP)], seven had two or more studies [busulfan, cyclosporine, azathioprine, cyclophosphamide, methoxsalen + ultraviolet (UV) radiation therapy, melphalan, and chlorambucil], and two did not have any studies [etoposide + bleomycin + cisplatin and treosulfan]. Cyclosporine and azathioprine reported increased skin cancer risk (SRR = 1.32, 95% CI 1.07–1.62; SRR = 1.56, 95% CI 1.25–1.93) compared to non-use. Cyclophosphamide increased bladder and hematologic cancer risk (SRR = 2.87, 95% CI 1.32–6.23; SRR = 2.43, 95% CI 1.65–3.58). Busulfan increased hematologic cancer risk (SRR = 6.71, 95% CI 2.49–18.08); melphalan was associated with hematologic cancer (SRR = 4.43, 95% CI 1.30–15.15). In the systematic review, methoxsalen + UV and MOPP wereassociated with an increased risk of skin and lung cancer, respectively. Our results can enhance persistent surveillance of group I pharmaceutical use, establish novel clinical strategies for patients with indications, and provide evidence for re-categorizing current group I pharmaceuticals into other groups. © 2024, The Author(s).N
Risk of clinically significant cardiovascular disease associated with postoperative radiotherapy in non-small cell lung cancer patients receiving surgical resection followed by adjuvant chemotherapy: A Korean nationwide cohort study
No full textBackground: There are no large-scale datasets that analyze the relationship between postoperative radiotherapy (PORT) and various cardiovascular diseases (CVDs) in patients with locally advanced non-small cell lung cancer (NSCLC). Therefore, we aimed to investigate the incidences of CVDs with PORT using a national populationbased database. Methods: Patients diagnosed with NSCLC who underwent curative surgery followed by adjuvant chemotherapy were included from 2007 to 2017. Patients with a prior diagnosis of heart failure (HF), atrial fibrillation (AFib), or heart surgery were excluded. A total of 11,141 patients were included in the final analysis. PORT was used in 1334 patients. Most patients received lobectomy with mediastinal lymph node dissection. Results: Major adverse cardiac events mostly occurred within 3-4 years from the diagnosis. After the median follow-up duration of 70.6 months, HF was the most diagnosed disease (5.3 %), followed by AFib (4.5 %), stroke (4.1 %), and pulmonary embolism (3.5 %). All the incidences of clinically significant CVDs did not differ by PORT. This result remained unchanged after the propensity score matching comparison. Age >= 65, underlying hypertension, and history of ischemic heart disease were the most related factors to the occurrence of HF and AFib. No significant difference in CVD-free survivals according to PORT status was observed. When stratified by proposed scoring, there were no subgroups showed increased incidence by PORT. Conclusions: These results suggest that PORT had no significant impact on various CVD occurrences in NSCLC patients without underlying heart disease.N
Bone regeneration using activin A/BMP2 chimera (AB204) with collagen membrane in rats with calvarial defects
No full textPurpose: Collagen has long been recognized as an excellent carrier for growth factors, and membrane-type collagen has been widely applied in dentistry for guided bone regeneration. This study was conducted to examine the effects of an activin A/BMP2 chimera (AB204) combined with a collagen membrane (CM) on bone repair in a rat calvarial defect model. Methods: A unilateral calvarial defect measuring 5.0 mm was surgically created in 32 Sprague-Dawley rats. The rats were then randomly assigned to 1 of 4 groups, each consisting of 8 animals: control (untreated), CM (treated with a CM only), CM/bone morphogenetic protein 2 (BMP2) (treated with a CM and 1.0 μg of BMP2), and CM/AB204 (treated with a CM and 1.0 μg of AB204). Bone regeneration was evaluated using micro-computed tomography (CT) and histological analysis at 2 and 4 weeks following surgery. Results: Micro-CT analysis revealed that bone formation in the CM/BMP2 and CM/AB204 groups was superior to that observed in the control and CM groups at both 2 and 4 weeks postoperatively. BMP2 induced greater bone regeneration than AB204 at 2 weeks; however, AB204 resulted in a greater bone volume at 4 weeks, achieving the highest values recorded. No significant differences were found between the CM/BMP2 and CM/AB204 groups at either time point (P>0.05). On histological examination, new bone formation was evident in both CM/BMP2 and CM/AB204 groups. Conclusions: Within the limitations of this study, the findings indicate that AB204 may enhance osteogenic potential when used in combination with CM for bone regeneration.N
Heavily phosphorus doped germanium with local strain compensation effect by Co-implantation and rapid thermal process
No full textThis study explored the effects and mechanisms of phosphorus (P), tin (Sn), and yttrium (Y) co-implantation in germanium (Ge). A series of dopant concentration measurements and electrical evaluations showed that the co-implantation process significantly enhanced P concentration in Ge, resulting in heavily doped regions. While P/Sn co-implantation showed limited advantages under low-temperature rapid thermal process (RTP), and P/Y co-implantation proved the effect of local strain compensation, the combined P/Sn/Y co-implantation achieved the highest concentration of P in Ge. At a RTP at 700 °C, we attained the remarkably high peak P concentration of 4.14×1020 atoms/cm3. This represents a 40-fold increase in P concentration compared to the conventional P single implantation method, using complementary metal-oxide semiconductor (CMOS)-compatible processes, and resulted in enhanced contact behavior. Geometric phase analysis (GPA) allowed visualization of the applied strains and stresses among the dopants and Ge atoms at nanometer resolution. The formation of strain-stress clusters by the large atomic radius Y was analyzed using GPA, and found to impact dopant distribution.N