Search results for: Jian Chen

Authors: Abazar Ghorbani, W. M. Wishwajith W. Kandegama, Seyed Mehdi Razavi, Moxian Chen

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The roles of hydrogen sulfide (H₂S) and melatonin (MT) as gasotransmitters in plants are widely recognised. Nevertheless, the precise nature of their involvement in defensive reactions remains uncertain. This study investigates the impact of the ML-H2S interaction on tomato plants exposed to vanadium (V) toxicity, focusing on synthesising secondary metabolites and V metal sequestration. The treatments applied in this study included a control (T1), V stress (T2), MT+V (T3), MT+H2S+V (T4), MT+hypotaurine (HT)+V (T5), and MT+H2S+HT+V (T6). These treatments were administered: MT (150 µM) as a foliar spray pre-treatment (3X), HT treatment (0.1 mM, an H2S scavenger) as root immersion for 12 hours as pre-treatments, and H2S (NaHS, 0.2 mM) and V (40 mg/L) treatments added to the Hoagland solution for 2 weeks. Results demonstrate that ML and H2S+ML treatments alleviate V toxicity by promoting the transcription of key genes (ANS, F3H, CHS, DFR, PAL, and CHI) involved in phenolic and anthocyanin biosynthesis. Moreover, they decreased V uptake and accumulation and enhanced the transcription of genes involved in glutathione and phytochelatin synthesis (GSH1, PCS, and ABC1), leading to V sequestration in roots and protection against V-induced damage. Additionally, ML and H2S+ML treatments optimize chlorophyll metabolism, and increase internal H2S levels, thereby promoting tomato growth under V stress. The combined treatment of ML+H2S shows superior effects compared to ML alone, suggesting synergistic/interactive effects between these two substances. Furthermore, inhibition of the beneficial impact of ML+H2S and ML treatments by HT, an H2S scavenger, underscores the significant involvement of H₂S in the signaling pathway activated by ML during V toxicity. Overall, these findings suggest that ML requires the presence of endogenous H₂S to mitigate V-induced adverse effects on tomato seedlings.

Keywords: vanadium toxicity, secondary metabolites, vanadium sequestration, h2s-melatonin crosstalk

Procedia PDF Downloads 48

Authors: Andy Zhang, Awnik Roy, Trevor B. Chen, Bibik Oleksandar, Subodh Adhikari, Paul S. Hsu

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The durability of a combustor in gas-turbine engines is a strong function of its component temperatures and requires good control of these temperatures. Since the temperature of combustion gases frequently exceeds the melting point of the combustion liner walls, an efficient air-cooling system with optimized flow rates of cooling air is significantly important to elongate the lifetime of liner walls. To determine the effectiveness of the air-cooling system, accurate two-dimensional (2D) surface temperature measurement of combustor liner walls is crucial for advanced engine development. Traditional diagnostic techniques for temperature measurement in this application include the rmocouples, thermal wall paints, pyrometry, and phosphors. They have shown some disadvantages, including being intrusive and affecting local flame/flow dynamics, potential flame quenching, and physical damages to instrumentation due to harsh environments inside the combustor and strong optical interference from strong combustion emission in UV-Mid IR wavelength. To overcome these drawbacks, a compact and small borescope long-wave-infrared (LWIR) sensor is developed to achieve 2D high-spatial resolution, high-fidelity thermal imaging of 2D surface temperature in gas-turbine engines, providing the desired engine component temperature distribution. The compactLWIRborescope sensor makes it feasible to promote the durability of a combustor in gas-turbine engines and, furthermore, to develop more advanced gas-turbine engines.

Keywords: borescope, engine, low-wave-infrared, sensor

Procedia PDF Downloads 136

Authors: M. Chen, H. Lee, D. M. Weary

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China is the world’s largest egg producer, with more than 90% of production occurring in conventional cages. Cage-free housing systems offer the potential for improving hen welfare, but the growth of this system requires consumer demand, making it is important to understand consumers’ willingness to engage with cage-free eggs. Previous survey research indicates that the majority of Chinese consumers have a basic understanding of cage-free eggs and that some are willing to pay a price premium for these eggs. The aim of this research is to understand consumer behaviour, experience, and motivations when purchasing cage-free eggs in China. Purposive sampling will be used to select 20 participants from each of 2 groups: 1) consumers of cage-free eggs and 2) sales representatives who promote these eggs directly to consumers in supermarkets. This 4-month study will use methods of virtual ethnography to interact with participants repeatedly. Consumers will be asked to share their egg shopping, cooking, and eating experiences, and sales representatives will be asked to share their experiences promoting the eggs to consumers. Data collection will involve audio-recorded interviews, informal conversations (casual texts and calls), participant observation (video calling during shopping, cooking, and eating), and informant diaries (written reflections, photos, videos). All data (field notes, transcripts, diaries, photos, and videos) will be analyzed using Thematic Analysis. We expect that these will result in a nuanced understanding of consumer purchasing behaviour and motivation and will thus help identify strategies to promote higher animal welfare and cage-free egg products in China.

Keywords: animal welfare, cage-free eggs, China, consumer behaviour, ethnography

Procedia PDF Downloads 106

Authors: Zixuan Zhao, Lingbin Du, Le Wang, Youqing Wang, Yi Yang, Jingjun Chen, Hengjin Dong

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Objectives: Few results from public attitudes for lung cancer screening are available both in China and abroad. This study aimed to identify preferred lung cancer screening modalities in a Chinese population and predict uptake rates of different modalities. Materials and Methods: A discrete choice experiment questionnaire was administered to 392 Chinese individuals aged 50–74 years who were at high risk for lung cancer. Each choice set had two lung screening options and an option to opt-out, and respondents were asked to choose the most preferred one. Both mixed logit analysis and stepwise logistic analysis were conducted to explore whether preferences were related to respondent characteristics and identify which kinds of respondents were more likely to opt out of any screening. Results: On mixed logit analysis, attributes that were predictive of choice at 1% level of statistical significance included the screening interval, screening venue, and out-of-pocket costs. The preferred screening modality seemed to be screening by low-dose computed tomography (LDCT) + blood test once a year in a general hospital at a cost of RMB 50; this could increase the uptake rate by 0.40 compared to the baseline setting. On stepwise logistic regression, those with no endowment insurance were more likely to opt out; those who were older and housewives/househusbands, and those with a health check habit and with commercial endowment insurance were less likely to opt out from a screening programme. Conclusions: There was considerable variance between real risk and self-perceived risk of lung cancer among respondents, and further research is required in this area. Lung cancer screening uptake can be increased by offering various screening modalities, so as to help policymakers further design the screening modality.

Keywords: lung cancer, screening, China., discrete choice experiment

Procedia PDF Downloads 261

Authors: Yuan-Jye Tseng, Ching-Yen Chen

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In the design cycle, a main design task is to determine the external shape of the product. The external shape of a product is one of the key factors that can affect the customers’ preferences linking to the motivation to buy the product, especially in the case of a consumer electronic product such as a mobile phone. The relationship between the external shape and the customer preferences needs to be studied to enhance the customer’s purchase desire and action. In this research, a design for customer preferences model is developed for investigating the relationships between the external shape and the customer preferences of a product. In the first stage, the names of the geometric features are collected and evaluated from the data of the specified internet web pages using the developed text miner. The key geometric features can be determined if the number of occurrence on the web pages is relatively high. For each key geometric feature, the numerical values are explored using the text miner to collect the internet data from the web pages. In the second stage, a cluster analysis model is developed to evaluate the numerical values of the key geometric features to divide the external shapes into several groups. Several design suggestion cases can be proposed, for example, large model, mid-size model, and mini model, for designing a mobile phone. A customer preference index is developed by evaluating the numerical data of each of the key geometric features of the design suggestion cases. The design suggestion case with the top ranking of the customer preference index can be selected as the final design of the product. In this paper, an example product of a notebook computer is illustrated. It shows that the external shape of a product can be used to drive customer preferences. The presented design for customer preferences model is useful for determining a suitable external shape of the product to increase customer preferences.

Keywords: cluster analysis, customer preferences, design evaluation, design for customer preferences, product design

Procedia PDF Downloads 191

Authors: Chaoyi Sun, Congxin Chen, Yun Zheng, Kaizong Xia, Wei Zhang

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Crest loads are often encountered in hydropower, highway, open-pit and other engineering rock slopes. Toppling failure is one of the most common deformation failure types of anti-dip bedding rock slopes. Analysis on such failure of anti-dip bedding rock slopes subjected to crest loads has an important influence on engineering practice. Based on the step-by-step analysis approach proposed by Goodman and Bray, a geo-mechanical model was developed, and the related analysis approach was proposed for the toppling failure of anti-dip bedding rock slopes subjected to crest loads. Using the transfer coefficient method, a formulation was derived for calculating the residual thrust of slope toe and the support force required to meet the requirements of the slope stability under crest loads, which provided a scientific reference to design and support for such slopes. Through slope examples, the influence of crest loads on the residual thrust and sliding ratio coefficient was investigated for cases of different block widths and slope cut angles. The results show that there exists a critical block width for such slope. The influence of crest loads on the residual thrust is non-negligible when the block thickness is smaller than the critical value. Moreover, the influence of crest loads on the slope stability increases with the slope cut angle and the sliding ratio coefficient of anti-dip bedding rock slopes increases with the crest loads. Finally, the theoretical solutions and numerical simulations using Universal Distinct Element Code (UDEC) were compared, in which the consistent results show the applicability of both approaches.

Keywords: anti-dip bedding rock slope, crest loads, stability analysis, toppling failure

Procedia PDF Downloads 179

Authors: Chia-Chen Hsieh, Fei-Hsiu Hsiao

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Objective: To examine the effects of supportive care interventions on depressive symptoms in patients with lung cancer. Methods: The databases of Cochrane Central Register of Controlled Trials (CENTRAL), Ovid EMBASE, PubMed, and Chinese Electronic Periodical Services (CEPS) were searched from their inception until September 2015. We included the studies with randomized controlled trial design that compared standard care with supportive care interventions using psychotherapeutic or exercises approach. The standardized mean differences (SMD) (Cohen’s d) were calculated to estimate the treatment effects. The Cochrane Risk of Bias Tool was used for quality assessment and subgroup analysis was conducted to identify possible sources of heterogeneity. Results: A total of 1472 patients with lung cancer were identified. Compared with standard care, the overall effects of all supportive care interventions significantly reduced depressive symptoms (SMD = -0.74 with 95% CI = -1.07 to -0.41), and the effect was maintained at the 4th, 8th, and 12th weeks of follow-up. Either psychotherapy combined with psychoeducation or exercise alone produced significant improvements in depressive symptoms, while psychoeducation alone did not. The greater improvements in depressive symptoms occurred in lung cancer patients with severe depressive symptoms at baseline, total duration of interventions of less than ten weeks, and intervention provided through face-to-face delivery. Conclusions: Psychotherapy combined with psychoeducation can help patients manage the causes of depressive symptoms, including both symptom distress and psychological trauma due to lung cancer. Exercise can target the impaired respiratory function that is a cause of depressive symptoms in lung cancer patients.

Keywords: supportive care intervention, depressive symptoms, lung cancer, meta-analysis

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Authors: Yujie Chen , Zhen Li

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In the context of planning transformation, how to promote public participation in the formulation and implementation of collaborative planning has been the focused issue of discussion. However, existing studies have often been case-specific or focused on a specific design field, leaving the role of participatory social media (PSM) in urban collaborative planning generally questioned. A systematic database search was conducted in December 2019. Articles and projects were eligible if they reported a quantitative empirical study applying participatory social media in the collaborative planning process (a prospective, retrospective, experimental, longitudinal research, or collective actions in planning practices). Twenty studies and seven projects were included in the review. Findings showed that social media are generally applied in public spatial behavior, transportation behavior, and community planning fields, with new technologies and new datasets. PSM has provided a new platform for participatory design, decision analysis, and collaborative negotiation most widely used in participatory design. Findings extracted several existing forms of PSM. PSM mainly act as three roles: the language of decision-making for communication, study mode for spatial evaluation, and decision agenda for interactive decision support. Three optimization content of PSM were recognized, including improving participatory scale, improvement of the grass-root organization, and promotion of politics. However, basically, participants only could provide information and comment through PSM in the future collaborative planning process, therefore the issues of low data response rate, poor spatial data quality, and participation sustainability issues worth more attention and solutions.

Keywords: participatory social media, collaborative planning, planning workshop, application mode

Procedia PDF Downloads 136

Authors: Jui-Chen Huang

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The purpose of this study is to explore the effects of telecare on preventing and delaying the quality of disability care in elderly people with portable comfort Bluetooth brainwave devices with remote healthcare functions. Through the teaching videos and remotely teaching the elderly, which had ever learned the care courses of the prevent and delay disability, these elderly did muscle strength training. Then this paper explores the effect of training with the data by SPSS 18.0 statistical software. The data is collected with pre-test, post-test and analyze data from the measure of the Bluetooth brain wave equipment including the pressure index, relaxation index, attention and fatigue index of the elderly. In this study, 30 elderly people who had taken preventive and delayed disability care courses were studied to explore the effect of their care quality improvement. The results showed that the pressure index, relaxation index, attention, and fatigue index of the elderly had statistically significant differences in two months. It can be seen that elderly people who have been treated to prevent and delay disability care courses can significantly improve their care quality if they continue to receive intensive training to prevent and delay disability through remote mode. This telecare is applied to the elderly program that has been used to prevent and delay disability care courses. It is worth continuing to promote, and it is recommended that follow-up studies be conducted in a longer-term manner to explore long-term benefits. It can solve the current insufficiency of long-term care resources, but the demand is urgent.

Keywords: telecare, bluetooth brainwave equipment, prevention and delay of disability, the elderly, care quality

Procedia PDF Downloads 152

Authors: Sheng-Bo Zhang, Huan-Hao Zhang, Zhi-Hua Chen, Chun Zheng

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In this paper, the Richtmyer-Meshkov instability has been studied numerically by using the high-resolution Roe scheme based on the two-dimensional unsteady Euler equation, which was caused by the interaction between shock wave and the helium circular light gas cylinder with different component distributions. The numerical results further discuss the deformation process of the gas cylinder, the wave structure of the flow field and quantitatively analyze the characteristic dimensions (length, height, and central axial width) of the gas cylinder, the volume compression ratio of the cylinder over time. In addition, the flow mechanism of shock-driven interface gas mixing is analyzed from multiple perspectives by combining it with the flow field pressure, velocity, circulation, and gas mixing rate. Then the effects of different initial component distribution conditions on interface instability are investigated. The results show when the diffusion interface transit to the sharp interface, the reflection coefficient gradually increases on both sides of the interface. When the incident shock wave interacts with the cylinder, the transmission of the shock wave will transit from conventional transmission to unconventional transmission. At the same time, the reflected shock wave is gradually strengthened, and the transmitted shock wave is gradually weakened, which leads to an increase in the Richtmyer-Meshkov instability. Moreover, the Atwood number on both sides of the interface also increases as the diffusion interface transit to the sharp interface, which leads to an increase in the Rayleigh-Taylor instability and the Kelvin-Helmholtz instability. Therefore, the increase in instability will lead to an increase the circulation, resulting in an increase in the growth rate of gas mixing rate.

Keywords: shock wave, He light cylinder, Richtmyer-Meshkov instability, Gaussian distribution

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Authors: Michelle Bulawan, Mei-Hua Chen

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Reading comprehension is crucial for acquiring information, analyzing critically, and achieving academic proficiency. However, there is a lack of growth in reading comprehension skills beyond fourth grade. The developmental shift from "learning to read" to "reading to learn" occurs around this stage. Factual knowledge and diverse views in articles enhance reading comprehension abilities. Nevertheless, some face difficulties due to evolving textual requirements, such as expanding vocabulary and using longer, more complex terminology. Most research on reading strategies has been conducted at the tertiary and secondary levels, while few have focused on the elementary levels. Furthermore, the use of character, ask, problem, solution (CAPS) charts in teaching reading has also been hardly explored. Thus, the researcher decided to explore the facilitation of active reading strategies through the CAPS chart and address the following research questions: a) What differences existed in elementary EFL learners' reading competency among those who engaged in active reading strategies and those who did not? b) What are the learners’ metacognitive skills of those who engage in active reading strategies and those who do not, and what are their effects on their reading competency? c) For those participants who engage in active reading activities, what are their perceptions about incorporating active reading activities into their English classroom learning? Two groups of elementary EFL learners, each with 18 students of the same level of English proficiency, participated in this study. Group A served as the control group, while Group B served as the experimental group. Two teachers also participated in this research; one of them was the researcher who handled the experimental group. The treatment lasts for one whole semester or seventeen weeks. In addition to the CAPS chart, the researcher also used the metacognitive awareness of reading strategy inventory (MARSI) and a ten-item, five-point Likert scale survey.

Keywords: active reading, EFL learners, metacognitive skills, reading competency, student’s perception

Procedia PDF Downloads 92

Authors: Ching-Yi Huang, Pi-Fen Cheng, Hui-Zhu Chen, Shi Ting Huang, Heng-Hua Wang

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This is a case of oral cancer after extensive resection and modified right lateral neck lymph node dissection followed by reconstruction with a skin flap. The nursing period lasted From September 25 to October 3, 2017, through observation, interview, physical assessment, and medical record review, the author identified the following nursing problems: acute pain, impaired oral mucous membrane, and body image change. During the nursing period, the author provided individual and overall nursing care and established mutual trust through the use of empathy. Author listened and eased the patient's physical indisposition, such as wound pain, we use medications and acupuncture massage to relieve pain. However, for oral mucosa change caused by surgery, provide continuous and complete oral care and oral exercise training to improve oral mucosal healing and restore swallowing function. In the body-image changes, guided him to express his feeling after the body-image change, and enhanced support and from the family, and encouraged him to attend head and neck cancer survivor alliance which allowed the patient to accept the altered body image and reaffirm self-worth. Hopefully, through sharing this nursing experience will help to the nursing care quality of nursing care for oral cancer patients after extensive resection and modified right lateral neck lymph node dissection followed by reconstruction with a skin flap.

Keywords: oral cancer, acute pain, impaired oral mucous membrane, body image change

Procedia PDF Downloads 188

Authors: Chen Zhi-Wei, Hsieh Wei-Fang

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Taiwan annual rainfall is global average of 2.5 times, plus city excessive development, green constantly to reduced, instead of is big area of artificial base disc, makes Taiwan rainy season during occurred of storm cannot timely of emissions, led to flood constantly, and rain also cannot was retained again using, led to city hydrological balance suffered damage, and to Regulation city of by brings of negative effect, increased green covered rate became most effective of method, and city land limited, so roof green gradually became a alternative program. Green roofs have become one of the Central and local government policy initiatives for urban development, in foreign countries, such as the United States, and Japan, and Singapore etc. Development of roof greening as an important policy, has become a trend of the times. In recent years, many experts and scholars are also on the roof greening all aspects of research, mostly for green roof for the environmental impact of benefits, such as: carbon reduction, cooling, thermostat, but research on the benefits of green roofs under water cut but it is rare. Therefore, this research literature from green roof in to view and analyze what kind of medium suitable for roof greening and use of green base plate combination simulated green roof structure, via different proportions of the medium with water retention plate and drainage board, experiment with different planting base plate combination of water conservation performance. Research will want to test the effect of roof planting base mix, promotion of relevant departments and agencies in future implementation of green roofs, prompted the development of green roofs, which in the end Taiwan achieve sustainable development of the urban environment help.

Keywords: thin-layer roof greening and planting medium, water efficiency

Procedia PDF Downloads 354

Authors: Yuan-Jye Tseng, Yi-Shiuan Chen

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The paper presented a sustainable design model for integrated evaluation of the design and supply chain of a product for the sustainable objectives. To design a product, there can be alternative ways to assign the detailed specifications to fulfill the same design objectives. In the design alternative cases, different material and manufacturing processes with various supply chain activities may be required for the production. Therefore, it is required to evaluate the different design cases based on the sustainable objectives. In this research, a closed-loop design model is developed by integrating the forward design model and reverse design model. From the supply chain point of view, the decisions in the forward design model are connected with the forward supply chain. The decisions in the reverse design model are connected with the reverse supply chain considering the sustainable objectives. The purpose of this research is to develop a mathematical model for analyzing the design cases by integrated evaluating the criteria in the closed-loop design and the closed-loop supply chain. The decision variables are built to represent the design cases of the forward design and reverse design. The cost parameters in a forward design include the costs of material and manufacturing processes. The cost parameters in a reverse design include the costs of recycling, disassembly, reusing, remanufacturing, and disposing. The mathematical model is formulated to minimize the total cost under the design constraints. In practical applications, the decisions of the mathematical model can be used for selecting a design case for the purpose of sustainable design of a product. An example product is demonstrated in the paper. The test result shows that the sustainable design model is useful for integrated evaluation of the design and the supply chain to achieve the sustainable objectives.

Keywords: closed-loop design, closed-loop supply chain, design evaluation, supply chain management, sustainable design model

Procedia PDF Downloads 426

Authors: Chen Jun

Abstract:

Antonia Susan Byatt’s Possession: A Romance has been misread as a postmodern pastiche novel since its publication because there are epics, epigraphs, lyrics, fairy tales, epistles, and even critical articles swollen in this work. The word ‘pastiche’ suggests messy, disorganized, and chaotic, which buries its artistic excellence while overlooking its subtitle, A Romance. The center of romance is the quest that the hero sets forth to conquer the adversity, hardship, and danger to accomplish a task to prove his identity or social worth. This paper argues that Byatt’s Possession is not a postmodern pastiche novel but rather a postmodern romance in which the characters in the academic world set forth their quest into the Victorian literary past that is nostalgically identified by Byatt as the Golden Age of English literature. In doing so, these five following issues are addressed: first, the origin of the protagonist Roland, and consequently, the nature of his quest; second, the central image of the dragon created by the fictional Victorian poet Henry Ash; third, Melusine as an image of female serpent created by the fictional Victorian poet Christabel LaMotte; fourth, the images of the two ladies; last, the image of water that links the dragon and the serpent. In Possession, the past is reinvented not as an unfortunate fall but as a Golden Age presented in the imaginative academic adventure. The dragon, a stereotypical symbol of evil, becomes the symbol of life in Byatt’s work, which parallels with the image of the mythical phoenix that can resurrect from its own ash. At the same time, the phoenix symbolizes Byatt’s efforts to revive the Victorian poetic art that is supposed to be dead in the post-capitalism society when the novel is the dominating literary genre and poetry becomes the minority. The fictional Victorian poet Ash is in fact Byatt’s own poetic mask through which she breathes life into the lost poetic artistry in the postmodern era.

Keywords: Byatt, possession, postmodern romance, literary past

Procedia PDF Downloads 416

Authors: Laurence Weinberg, Dominic Walpole, Dong-Kyu Lee, Michael D’Silva, Jian W. Chan, Lachlan F. Miles, Bradley Carp, Adam Wells, Tuck S. Ngun, Siven Seevanayagam, George Matalanis, Ziauddin Ansari, Rinaldo Bellomo, Michael Yii

Abstract:

Background: There have been multiple recent advancements in the selection, optimization and management of cardiac surgical patients. However, there is limited data regarding the outcomes of nonagenarians undergoing cardiac surgery, despite this vulnerable cohort increasingly receiving these interventions. This study describes the patient characteristics, management and outcomes of a group of nonagenarians undergoing cardiac surgery in the context of contemporary peri-operative care. Methods: A retrospective observational study was conducted of patients 90 to 99 years of age (i.e., nonagenarians) who had undergone cardiac surgery requiring a classic median sternotomy (i.e., open-heart surgery). All operative indications were included. Patients who underwent minimally invasive surgery, transcatheter aortic valve implantation and thoracic aorta surgery were excluded. Data were collected from four hospitals in Victoria, Australia, over an 8-year period (January 2012 – December 2019). The primary objective was to assess six-month mortality in nonagenarians undergoing open-heart surgery and to evaluate the incidence and severity of postoperative complications using the Clavien-Dindo classification system. The secondary objective was to provide a detailed description of the characteristics and peri-operative management of this group. Results: A total of 12,358 adult patients underwent cardiac surgery at the study centers during the observation period, of whom 18 nonagenarians (0.15%) fulfilled the inclusion criteria. The median (IQR) [min-max] age was 91 years (90.0:91.8) [90-94] and 14 patients (78%) were men. Cardiovascular comorbidities, polypharmacy and frailty, were common. The median (IQR) predicted in-hospital mortality by EuroSCORE II was 6.1% (4.1-14.5). All patients were optimized preoperatively by a multidisciplinary team of surgeons, cardiologists, geriatricians and anesthetists. All index surgeries were performed on cardiopulmonary bypass. Isolated coronary artery bypass grafting (CABG) and CABG with aortic valve replacement were the most common surgeries being performed in four and five patients, respectively. Half the study group underwent surgery involving two or more major procedures (e.g. CABG and valve replacement). Surgery was undertaken emergently in 44% of patients. All patients except one experienced at least one postoperative complication. The most common complications were acute kidney injury (72%), new atrial fibrillation (44%) and delirium (39%). The highest Clavien-Dindo complication grade was IIIb occurring once each in three patients. Clavien-Dindo grade IIIa complications occurred in only one patient. The median (IQR) postoperative length of stay was 11.6 days (9.8:17.6). One patient was discharged home and all others to an inpatient rehabilitation facility. Three patients had an unplanned readmission within 30 days of discharge. All patients had follow-up to at least six months after surgery and mortality over this period was zero. The median (IQR) duration of follow-up was 11.3 months (6.0:26.4) and there were no cases of mortality observed within the available follow-up records. Conclusion: In this group of nonagenarians undergoing cardiac surgery, postoperative six-month mortality was zero. Complications were common but generally of low severity. These findings support carefully selected nonagenarian patients being offered cardiac surgery in the context of contemporary, multidisciplinary perioperative care. Further, studies are needed to assess longer-term mortality and functional and quality of life outcomes in this vulnerable surgical cohort.

Keywords: cardiac surgery, mortality, nonagenarians, postoperative complications

Procedia PDF Downloads 121

Authors: Yi-Ling Chen, Dung-Ying Lin

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In the manufacturing process, computer numerical control (CNC) machining plays a crucial role. CNC enables precise machinery control through computer programs, achieving automation in the production process and significantly enhancing production efficiency. However, traditional CNC production lines often require manual intervention for loading and unloading operations, which limits the production line's operational efficiency and production capacity. Additionally, existing CNC automation systems frequently lack sufficient intelligence and fail to achieve optimal configuration efficiency, resulting in the need for substantial time to reconfigure production lines when producing different products, thereby impacting overall production efficiency. Using the NSGA-II algorithm, we generate production line layout configurations that consider field constraints and select robotic arm specifications from an arm list. This allows us to calculate loading and unloading times for each job order, perform demand allocation, and assign processing sequences. The NSGA-II algorithm is further employed to determine the optimal processing sequence, with the aim of minimizing demand completion time and maximizing average machine utilization. These objectives are used to evaluate the performance of each layout, ultimately determining the optimal layout configuration. By employing this method, it enhance the configuration efficiency of CNC production lines and establish an adaptive capability that allows the production line to respond promptly to changes in demand. This will minimize production losses caused by the need to reconfigure the layout, ensuring that the CNC production line can maintain optimal efficiency even when adjustments are required due to fluctuating demands.

Keywords: evolutionary algorithms, multi-objective optimization, pareto optimality, layout optimization, operations sequence

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Authors: Xiangxiang Chen

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This paper explores a recent online trending activity in metropolitan China. Originating from Jane Jacob's walking tour, 'citywalk' has gradually developed into a wanghong (social media trending) activity, contributing to a revitalized mode of urbanism in post-modernized China. Former researchers have dug into the walking patterns in everyday cities, but few have looked into the short trip activities conducted by local residents and people nearby. Although some Chinese researchers have focused on wanghong economy and the related wanghong urbanism, they have linked it to the 'check-in' activities but not the 'citywalk', which connects several spots for 'checking in' and usually take place in a historic while cultural neighborhood. Besides, many research articles have focused on gentrification, but few have explored a gentrification pattern that differs from that in developed countries. This research uses short semi-structured interviews, which range from 3 to 5 minutes, combining a comparison model to find out the reasons and the feelings of people to go on the 'citywalk' and the economic development influenced by it. The research location was in Foshan's most historic area -the Chuihong neighborhood, which is situated in the metropolitan area of the Guangdong province. The paper finds out that social media in China has heavily influenced urban revitalization, leading to a new kind of gentrification mode. This suggests that the government should give historical and cultural neighborhoods enough freedom to develop independently. This paper aims to provide urban revitalization strategies to build a 'citywalk' friendly and aesthetically attractive neighborhood in China.

Keywords: tourism development, urban revitalization, social media, wanghong urbanism, city walk, China

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Authors: Zhenyi Chen

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With the rise of China and the escalation of tension between China and the United States, European countries led by Great Britain, France, and Germany pay increasing attention to the regional situation in the Asia-Pacific (now known as "Indo-Pacific"). Among them, the South China Sea (SCS) is one of the main areas disputed by China, the United States, Southeast Asian countries and some European countries. Western countries are worried that the rise of China's military power will break the stability of the situation in SCS and alter the balance of power among major powers. Therefore, they tried to balance China's rise through alliance. In France's Indo-Pacific strategy, France aims to build a regional order with the alliance of France, India and Australia as the core, and regularly carry out military exercises targeting SCS with the United States, Japan and Southeast Asian countries. For China, the instability of the situation in SCS could also threaten the security of the southeast coastal areas and Taiwan, affect China's peaceful development process, and pose a threat to China's territorial sovereignty. This paper aims to study the activities and motivation of France in the South China Sea, and put the situation in SCS under the perspective of Balance of Power Theory, focusing on China, America and France. To be more specific, this paper will first briefly introduce Balance of Power Theory, then describe the new trends of France in recent years, followed with the analysis on the motivation of the increasing trend of France's involvement in SCS, and finally analyze the situation in SCS from the perspective of "balance of power" theory. It will be argued that great powers are carefully maintaining the balance of military power in SCS, and it is highly possible that this trend would still last in the middle and long term, particularly via military deployment and strategic alliances.

Keywords: South China Sea, France, China, balance of power theory, Indo-Pacific

Procedia PDF Downloads 176

Authors: Ying Han, Yuanxiang Chen, Yongtao Huang, Jia Fu, Kaile Li, Shangjing Lin, Jianguo Yu

Abstract:

In long-haul and high-speed optical transmission system, the orthogonal frequency division multiplexing (OFDM) signal suffers various linear and non-linear impairments. In recent years, researchers have proposed compensation schemes for specific impairment, and the effects are remarkable. However, different impairment compensation algorithms have caused an increase in transmission delay. With the widespread application of deep neural networks (DNN) in communication, multi-impairment compensation based on DNN will be a promising scheme. In this paper, we propose and apply DNN to compensate multi-impairment of 16-QAM coherent optical OFDM signal, thereby improving the performance of the transmission system. The trained DNN models are applied in the offline digital signal processing (DSP) module of the transmission system. The models can optimize the constellation mapping signals at the transmitter and compensate multi-impairment of the OFDM decoded signal at the receiver. Furthermore, the models reduce the peak to average power ratio (PAPR) of the transmitted OFDM signal and the bit error rate (BER) of the received signal. We verify the effectiveness of the proposed scheme for 16-QAM Coherent Optical OFDM signal and demonstrate and analyze transmission performance in different transmission scenarios. The experimental results show that the PAPR and BER of the transmission system are significantly reduced after using the trained DNN. It shows that the DNN with specific loss function and network structure can optimize the transmitted signal and learn the channel feature and compensate for multi-impairment in fiber transmission effectively.

Keywords: coherent optical OFDM, deep neural network, multi-impairment compensation, optical transmission

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Authors: An Chengrui, Yin Zi, Wu Bingbing, Ma Yuanzhu, Jin Kaixiu, Chen Xiao, Ouyang Hongwei

Abstract:

Single cell RNA sequence (scRNA-seq) is one of the effective tools to study transcriptomics of biological processes. Recently, similarity measurement of cells is Euclidian distance or its derivatives. However, the process of scRNA-seq is a multi-variate Bernoulli event model, thus we hypothesize that it would be more efficient when the divergence between cells is valued with relative entropy than Euclidian distance. In this study, we compared the performances of Euclidian distance, Spearman correlation distance and Relative Entropy using scRNA-seq data of the early, medial and late stage of limb development generated in our lab. Relative Entropy is better than other methods according to cluster potential test. Furthermore, we developed KL-SNE, an algorithm modifying t-SNE whose definition of divergence between cells Euclidian distance to Kullback–Leibler divergence. Results showed that KL-SNE was more effective to dissect cell heterogeneity than t-SNE, indicating the better performance of relative entropy than Euclidian distance. Specifically, the chondrocyte expressing Comp was clustered together with KL-SNE but not with t-SNE. Surprisingly, cells in early stage were surrounded by cells in medial stage in the processing of KL-SNE while medial cells neighbored to late stage with the process of t-SNE. This results parallel to Heatmap which showed cells in medial stage were more heterogenic than cells in other stages. In addition, we also found that results of KL-SNE tend to follow Gaussian distribution compared with those of the t-SNE, which could also be verified with the analysis of scRNA-seq data from another study on human embryo development. Therefore, it is also an effective way to convert non-Gaussian distribution to Gaussian distribution and facilitate the subsequent statistic possesses. Thus, relative entropy is potentially a better way to determine the divergence of cells in scRNA-seq data analysis.

Keywords: Single cell RNA sequence, Similarity measurement, Relative Entropy, KL-SNE, t-SNE

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Authors: Ming-Hong Chen

Abstract:

In the study, the mechanical and financial feasibility for the compressed air energy storage (CAES) system in the porous media reservoir in Taiwan is evaluated. In 2035, Taiwan aims to install 16.7 GW of wind power and 40 GW of photovoltaic (PV) capacity. However, renewable energy sources often generate more electricity than needed, particularly during winter. Consequently, Taiwan requires long-term, large-scale energy storage systems to ensure the security and stability of its power grid. Currently, the primary large-scale energy storage options are Pumped Hydro Storage (PHS) and Compressed Air Energy Storage (CAES). Taiwan has not ventured into CAES-related technologies due to geological and cost constraints. However, with the imperative of achieving net-zero carbon emissions by 2050, there's a substantial need for the development of a considerable amount of renewable energy. PHS has matured, boasting an overall installed capacity of 4.68 GW. CAES, presenting a similar scale and power generation duration to PHS, is now under consideration. Taiwan's geological composition, being a porous medium unlike salt caves, introduces flow field resistance affecting gas injection and extraction. This study employs a program analysis model to establish the system performance analysis capabilities of CAES. The finite volume model is then used to assess the impact of porous media, and the findings are fed back into the system performance analysis for correction. Subsequently, the financial implications are calculated and compared with existing literature. For Taiwan, the strategic development of CAES technology is crucial, not only for meeting energy needs but also for decentralizing energy allocation, a feature of great significance in regions lacking alternative natural resources.

Keywords: compressed-air energy storage, efficiency, porous media, financial feasibility

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Authors: Saeid Seddegh, Xiaolin Wang, Alan D. Henderson, Dong Chen, Oliver Oims

Abstract:

The main objective of this research is to study the heat transfer processes and phase change behaviour of a phase change material (PCM) in shell and tube latent heat thermal energy storage (LHTES) systems. The thermal behaviour in a vertical and horizontal shell-and-tube heat energy storage system using a pure thermal conduction model and a combined conduction-convection heat transfer model is compared in this paper. The model is first validated using published experimental data available in literature and then used to study the temperature variation, solid-liquid interface, phase distribution, total melting and solidification time during melting and solidification processes of PCMs. The simulated results show that the combined convection and conduction model can better describe the energy transfer in PCMs during melting process. In contrast, heat transfer by conduction is more significant during the solidification process since the two models show little difference. Also, it was concluded that during the charging process for the horizontal orientation, convective heat transfer has a strong effect on melting of the upper part of the solid PCM and is less significant during melting of the lower half of the solid PCM. However, in the vertical orientation, convective heat transfer is the same active during the entire charging process. In the solidification process, the thermal behavior does not show any difference between horizontal and vertical systems.

Keywords: latent heat thermal energy storage, phase change material, natural convection, melting, shell and tube heat exchanger, melting, solidification

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Authors: Asad Iqbal, Feixiang Zan, Xiaoming Liu, Guang-Hao Chen

Abstract:

Water, food, and energy nexus is a vital subject to achieve sustainable development goals worldwide. Wastewater (WW) and food waste (FW) from municipal sources are primary contributors to their respective wastage sum from a country. Along with the loss of these invaluable natural resources, their treatment systems also consume a lot of abiotic energy and resources input with a perceptible contribution to global warming. Hence, the global paradigm has evolved from simple pollution mitigation to a resource recovery system (RRS). In this study, the prospects of six alternative FW treatment scenarios are quantitatively evaluated for Hong Kong in terms of energy use and greenhouse emissions (GHEs) potential, using life cycle assessment (LCA). Considered scenarios included: aerobic composting, anaerobic digestion (AD), combine AD and composting (ADC), co-disposal, and treatment with wastewater (CoD-WW), incineration, and conventional landfilling as base-case. Results revealed that in terms of GHEs saving, all-new scenarios performed significantly better than conventional landfilling, with ADC scenario as best-case and incineration, AD alone, CoD-WW ranked as second, third, and fourth best respectively. Whereas, composting was the worst-case scenario in terms of energy balance, while incineration ranked best and AD alone, ADC, and CoD-WW ranked as second, third, and fourth best, respectively. However, these results are highly sensitive to boundary settings, e.g., the inclusion of the impact of biogenic carbon emissions and waste collection and transportation, and several other influential parameters. The study provides valuable insights and policy guidelines for the decision-makers locally and a generic modelling template for environmental impact assessment.

Keywords: food waste, resource recovery, greenhouse emissions, energy balance

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Authors: Kuo-Wei Hsu, Jen-Chih, Chao, Pei-Chen, Wu

Abstract:

With the rapid development of global economy, the increasing population, the highly industrialization, greenhouse gas emission and the ozone layer damage, the Global Warming happens. Facing the impact of global warming, the issue of “green transportation” began to be valued and promoted in each city. Taichung has been elected as the model of low-carbon city in Taiwan. To comply with international trends and the government policy, we tried to promote the energy saving and carbon reduction to create a “low-carbon Taichung with green life and eco-friendly economy”. To cooperate with the “green transportation” project, Taichung has promoted a number of public transports constructions and traffic policy in recent years like BRT, MRT, etc. The elevated railway is one of those important constructions. Cooperating with the green transport policy, elevated railway could help to achieve the carbon reduction for this low-carbon city. The current studies of the carbon emissions associated with railways and roads are focusing on the assessment on paving material, institutional policy and economic benefit. Except for changing the mode of transportation, elevated railways/roads also create space under the bridge. However, there is no research about the carbon emissions of the space underneath the elevated section up until now. This study investigated the effect of railway track elevation project in Taichung based on the carbon emissions and the factors that affect carbon emissions by research related theory and literature analysis. This study concluded that : railway track elevation increased the public transit, the bike lanes, the green areas and walking spaces. In the other hand it reduced the traffic congestions, the use of motorcycles as well as automobiles for carbon emissions.

Keywords: low-carbon city, green transportation, carbon emissions, Taichung, Taiwan

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Authors: Jyh-Yi Shih, Chie-Bein Chen, Kuang-Yi Lin, Yu-Wei Huang

Abstract:

Because of the trend toward globalization, Taiwanese companies have gradually focused more on overseas market operations. Overseas market performance has gradually increased as a proportion of Taiwanese companies’ total business revenues. Existing international investment theories cannot explain numerous new phenomena in this domain. Opinions are inconsistent, and contradictory positions exist regarding the antecedents of multinational enterprise (MNE) performance. This study applied contemporary internalization theory to establish and extend approaches adopted by previous relevant studies. In the context of the overseas market, the influence that MNE investment in research and development (R&D) and marketing has on enterprise performance was investigated from the firm-specific advantages (FSAs) and country-specific advantages (CSAs) perspectives. CSAs and internationalization speed were addressed as moderators, and hypotheses regarding how internationalization and performance were achieved through MNE overseas market operation were explored to ensure the completeness of the investigation. The list of enterprises was sourced from the Taiwan Economic Journal. After examining the relevant data, the following conclusions were obtained: (a) The relationship between the level of FSAs in R&D and enterprise performance exhibited an S-shaped curve. (b) The relationship between the level of FSAs in marketing and enterprise performance displayed a U-shaped curve. (c) The extent to which potential CFAs were obtained positively moderated the relationship between enterprise investment in R&D to gain FSAs and MNE performance. (d) Internationalization speed positively moderated the relationship between MNEs and enterprise investment in R&D and marketing to gain FSAs.

Keywords: multinational corporation, firm-specific advantages, country-specific advantages, international speed

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Authors: Yi-Lin Chen, Sheng-Jou Hung, Tsunglin Liu

Abstract:

Adaptive immune system recognizes a wide range of antigens via expressing a large number of structurally distinct T cell and B cell receptor genes. The distinct receptor genes arise from complex rearrangements called V(D)J recombination, and constitute the immune repertoire. A common method of profiling immune repertoire is via amplifying recombined receptor genes using multiple primers and high-throughput sequencing. This multiplex-PCR approach is efficient; however, the resulting repertoire can be distorted because of primer bias. To eliminate primer bias, 5’ RACE is an alternative amplification approach. However, the application of RACE approach is limited by its low efficiency (i.e., the majority of data are non-regular receptor sequences, e.g., containing intronic segments) and lack of the convenient tool for analysis. We propose a computational tool that can correctly identify non-regular receptor sequences in RACE data via aligning receptor sequences against the whole gene instead of only the exon regions as done in all other tools. Using our tool, the remaining regular data allow for an accurate profiling of immune repertoire. In addition, a RACE approach is improved to yield a higher fraction of regular T-cell receptor sequences. Finally, we quantify the degree of primer bias of a multiplex-PCR approach via comparing it to the RACE approach. The results reveal significant differences in frequency of VJ combination by the two approaches. Together, we provide a new experimental and computation pipeline for an unbiased profiling of immune repertoire. As immune repertoire profiling has many applications, e.g., tracing bacterial and viral infection, detection of T cell lymphoma and minimal residual disease, monitoring cancer immunotherapy, etc., our work should benefit scientists who are interested in the applications.

Keywords: immune repertoire, T-cell receptor, 5' RACE, high-throughput sequencing, sequence alignment

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Authors: Yuekun Chen, Yousef Sardahi, Salam Hajjar, Christopher Greer

Abstract:

This paper presents a multi-objective optimal design of a cascade control system for an underactuated mechanical system. Cascade control structures usually include two control algorithms (inner and outer). To design such a control system properly, the following conflicting objectives should be considered at the same time: 1) the inner closed-loop control must be faster than the outer one, 2) the inner loop should fast reject any disturbance and prevent it from propagating to the outer loop, 3) the controlled system should be insensitive to measurement noise, and 4) the controlled system should be driven by optimal energy. Such a control problem can be formulated as a multi-objective optimization problem such that the optimal trade-offs among these design goals are found. To authors best knowledge, such a problem has not been studied in multi-objective settings so far. In this work, an underactuated mechanical system consisting of a rotary servo motor and a ball and beam is used for the computer simulations, the setup parameters of the inner and outer control systems are tuned by NSGA-II (Non-dominated Sorting Genetic Algorithm), and the dominancy concept is used to find the optimal design points. The solution of this problem is not a single optimal cascade control, but rather a set of optimal cascade controllers (called Pareto set) which represent the optimal trade-offs among the selected design criteria. The function evaluation of the Pareto set is called the Pareto front. The solution set is introduced to the decision-maker who can choose any point to implement. The simulation results in terms of Pareto front and time responses to external signals show the competing nature among the design objectives. The presented study may become the basis for multi-objective optimal design of multi-loop control systems.

Keywords: cascade control, multi-Loop control systems, multiobjective optimization, optimal control

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Authors: Chen Jun-Hong, He Pu, Tao Wen-Quan

Abstract:

Proton exchange membrane fuel cell (PEMFC) is the most promising future energy source owing to its low operating temperature, high energy efficiency, high power density, and environmental friendliness. In this paper, a comprehensive PEMFC system control-oriented model is developed in the Matlab/Simulink environment, which includes the hydrogen supply subsystem, air supply subsystem, and thermal management subsystem. Besides, Improved Artificial Bee Colony (IABC) is used in the parameter identification of PEMFC semi-empirical equations, making the maximum relative error between simulation data and the experimental data less than 0.4%. Operation temperature is essential for PEMFC, both high and low temperatures are disadvantageous. In the thermal management subsystem, water pump and fan are both controlled with the PID controller to maintain the appreciate operation temperature of PEMFC for the requirements of safe and efficient operation. To improve the control effect further, fuzzy control is introduced to optimize the PID controller of the pump, and the Radial Basis Function (RBF) neural network is introduced to optimize the PID controller of the fan. The results demonstrate that Fuzzy-PID and RBF-PID can achieve a better control effect with 22.66% decrease in Integral Absolute Error Criterion (IAE) of T_st (Temperature of PEMFC) and 77.56% decrease in IAE of T_in (Temperature of inlet cooling water) compared with traditional PID. In the end, a novel thermal management structure is proposed, which uses the cooling air passing through the main radiator to continue cooling the secondary radiator. In this thermal management structure, the parasitic power dissipation can be reduced by 69.94%, and the control effect can be improved with a 52.88% decrease in IAE of T_in under the same controller.

Keywords: PEMFC system, parameter identification, temperature control, Fuzzy-PID, RBF-PID, parasitic power

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Authors: Masoud Irannezhad, Sirpa Rasmus, Saghar Ahmadian, Deliang Chen, Bjorn Klove

Abstract:

Variability and changes in thermal conditions play a crucial role in functioning of human society, particularly over cold climate regions like Finland. Accordingly, the frost-free season (FFS) parameters in terms of start (FFSS), end (FFSE) and length (FFSL) have substantial effects not only on natural environment (e.g. flora and fauna), but also on human requirements (e.g. agriculture, forestry and energy generation). Applying the 0°C threshold of minimum temperature (Tmin), the FFS was defined as the period between the last spring frost as FFSS and the first fall frost as FFSE. For this study, gridded (10 x 10 km2) daily minimum temperature datasets throughout Finland during 1961-2011 was used to investigate recent spatio-temporal variations and trends in frost-free season (FFS) parameters and their relationships with the well-known large-scale climate teleconnections (CTs). The FFS in Finland naturally increases from north (~60 days) to south (~190 days), in association with earlier FFSS (~24 April) and later FFSE (~30 October). Statistically significant (p<0.05) trends in FFSL were all positive (increasing) ranged between 0 and 13.5 (days/decade) and mainly observed in the east, upper west, centre and upper north of Finland. Such lengthening trends in FFS were attributable to both earlier FFSS and later FFSE mostly over central and upper northern Finland, while only to later FFSE in eastern and upper western parts. Variations in both FFSL and FFSS were significantly associated with the Polar (POL) pattern over northern Finland, while with the East Atlantic (EA) pattern over eastern and upper western areas. However, the POL and Scandinavia (SCA) patterns were most influential CTs for FFSE variability over northern Finland.

Keywords: climate teleconnections, Finland, frost-free season, trend analysis

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