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The expectations within higher education to improve online STEM courses have continued to increase. The pressure to do so particularly pertains to the lower-level introductory courses that act as gatekeeping courses to various STEM-related majors. Rather than working alone to improve their courses, more instructors for these courses pair with the respective instructional designers at their institutions to refresh or revise, their online courses. This study examines the revisions of a two-part introduction-to-biology series of online courses with their respective online labs over the span of three years, and from a sampling of 905 students, compares the final scores from the courses and the labs between each iteration. Findings indicate that multiple iterations of a course have the potential to increase student outcomes and to decrease the student dropout rate over time. Additionally, purely online students can perform differently in response to course revisions in comparison to the online students who also enroll in non-online courses, implying that the needs of online-only students may differ from those who have a blended learning experience. [ABSTRACT FROM AUTHOR]

European Public Service Media (PSM) have implemented innovation departments or labs that seem to be useful for experimenting and developing innovative ideas regarding technologies, content, audiences and other areas. We have identified 17 PSM labs. We analyse these units through the lens of the Model of Coordinated Action developed by Lee and Paine (2015) and the concept of "Community of Practice" that describes how a group communicates, learns, participates and transforms their practice, drawing from Wenger's theory (1998). This study addresses how innovative PSM labs are managed, focusing on the cases of BBC News Labs and RTVE Lab. The methodology is based on participant observation in their workplaces, as well as semi-structured interviews with a purposive sample of 23 managers and employees. The results highlight that both teams manage innovation in their functional organization through learning processes among their professionals and transfer their innovations to other areas of their respective corporations. PSM labs encourage their team members to innovate through a collaborative culture that makes it possible to identify them as Communities of Practice that foster coordinated action and learning in their work. Their organizational culture relies on a strategy that seeks to increase their public service function. [ABSTRACT FROM AUTHOR]

Differential equations are widely used tools for modelling the world around us, making a course in differential equations a natural place for students to connect concrete mathematical applications to abstract concepts. Since students grasp the concepts better by applying them, introducing differential equations through modelling becomes essential. However, students often struggle to create and understand these models in the course. The purpose of this article is to share and examine a scaffolded sequence of labs implemented at regular intervals throughout a semester intended to train students in construction and analysis of mathematical models using differential equations. In these labs students learn basic principles of modelling that better prepare them for many of the high-quality modelling projects already available in differential equations. The course in which these activities were developed is taught using the SIMIODE text, Differential Equations: A Toolbox for Modelling the World, by Kurt Bryan. The labs are split into two components, with the first completed during class time and the second as out of class assignments. Furthermore, the course was re-organised to allow for the time needed to introduce the labs in class. We include classroom materials for labs, analysis, results on student perceptions and pedagogical recommendations. [ABSTRACT FROM AUTHOR]

ABSTRACTAgent-based evolutionary, computational systems have been proven to be an efficient concept for solving complex computational problems. This paper is an extension of [Biełaszek, S., Piętak, K., & Kisiel-Dorohinicki, M. (2021). New extensions of reproduction operators in solving LABS problem using EMAS meta-heuristic. Springer, cop. 2021. – Lecture Notes in Artificial Intelligence, Computational collective intelligence 12876 304-316. 13th International Conference, ICCCI 2021: Rhodes, Greece, September 29ŰOctober 1, 2021.] where we proposed new variants of reproduction operators together with new heuristics for the generation of initial population, dedicated to LABS – a hard discrete optimization problem. In this research, we verify if the proposed recombination operators improve EMAS efficiency also with different local optimization techniques such as Tabu Search and Self-avoiding walk, and therefore can be seen as better recombination operators dedicated to LABS problem in general. This paper recalls the definition of new recombination variants dedicated to LABS and verify if they can be successfully used in many different evolutionary configurations.

Agent-based evolutionary, computational systems have been proven to be an efficient concept for solving complex computational problems. This paper is an extension of [Biełaszek, S., Piętak, K., & Kisiel-Dorohinicki, M. (2021). New extensions of reproduction operators in solving LABS problem using EMAS meta-heuristic. Springer, cop. 2021. – Lecture Notes in Artificial Intelligence, Computational collective intelligence 12876 304-316. 13th International Conference, ICCCI 2021: Rhodes, Greece, September 29ŰOctober 1, 2021.] where we proposed new variants of reproduction operators together with new heuristics for the generation of initial population, dedicated to LABS – a hard discrete optimization problem. In this research, we verify if the proposed recombination operators improve EMAS efficiency also with different local optimization techniques such as Tabu Search and Self-avoiding walk, and therefore can be seen as better recombination operators dedicated to LABS problem in general. This paper recalls the definition of new recombination variants dedicated to LABS and verify if they can be successfully used in many different evolutionary configurations. [ABSTRACT FROM AUTHOR]

• hNa v 1.9_C4 chimera in CHOK-1 cells encompasses the extracellular and transmembrane domain of hNa v 1.9. • Synthetic cannabinoid ACEA blocked hNa v 1.9_C4+ß1 currents causing a hyperpolarizing shift in inactivation. • hNa v 1.9_C4 channels display window currents, significantly reduced by ACEA. • Computationally, ACEA binds the local anaesthetic binding site. • The local anaesthetic profile of ACEA may be involved in cannabinoid analgesia. Cannabinoids regulate analgesia, which has aroused much interest in identifying new pharmacological therapies in the management of refractory pain. Voltage-gated Na+ channels (Na v s) play an important role in inflammatory and neuropathic pain. In particular, Na v 1.9 is involved in nociception and the understanding of its pharmacology has lagged behind because it is difficult to express in heterologous systems. Here, we utilized the chimeric channel hNa v 1.9_C4, that comprises the extracellular and transmembrane domains of hNa v 1.9, co-expressed with the ß1 subunit on CHO-K1 cells to characterize the electrophysiological effects of ACEA, a synthetic surrogate of the endogenous cannabinoid anandamide. ACEA induced a tonic block, decelerated the fast inactivation, markedly shifted steady-state inactivation in the hyperpolarized direction, decreasing the window current and showed use-dependent block, with a high affinity for the inactivated state (k i = 0.84 µM). Thus, we argue that ACEA possess a local anaesthetic-like profile. To provide a mechanistic understanding of its mode of action at the molecular level, we combined induced fit docking with Monte Carlo simulations and electrostatic complementarity. In agreement with the experimental evidence, our computer simulations revealed that ACEA binds Tyr1599 of the local anaesthetics binding site of the hNa v 1.9, contacting residues that bind cannabinol (CBD) in the Na v Ms channel. ACEA adopted a conformation remarkably similar to the crystallographic conformation of anandamide on a non-homologous protein, obstructing the Na+ permeation pathway below the selectivity filter to occupy a highly conserved binding pocket at the intracellular side. These results describe a mechanism of action, possibly involved in cannabinoid analgesia. [ABSTRACT FROM AUTHOR]

Mario Cazzola,1 Paola Rogliani,1 Rossella Laitano,1 Luigino Calzetta,2 Maria Gabriella Matera3 1Unit of Respiratory Medicine, Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy; 2Unit of Respiratory Diseases and Lung Function, Department of Medicine and Surgery, University of Parma, Parma, Italy; 3Unit of Pharmacology, Department of Experimental Medicine, University of Campania Luigi Vanvitelli, Naples, ItalyCorrespondence: Mario Cazzola Email mario.cazzola@uniroma2.itAbstract: Although pharmacological treatment of COPD is codified in different guidelines and strategy documents, there is abundant evidence of discrepancy between what they suggest and what health professionals prescribe, especially in low-risk groups where there is widespread overprescription of triple therapy. It is therefore necessary to clarify when the use of triple therapy is indicated in COPD patients and when it is preferable to maintain treatment with dual bronchodilation. In this article, we discuss our views based on our experience and what is reported in the literature and try to give answers to these two questions. The evidence generated by pivotal RCTs supports the use of triple therapy in patients who present for the first time and have severe airway obstruction, are symptomatic, have had frequent moderate or severe exacerbations in the previous year, and have peripheral eosinophilia. However, it is difficult to determine whether step-up is useful in all other cases because the available data are quite conflicting. It is likely that the inconsistency in the information generated by the various available studies may explain the prescribing behaviour of many physicians who do not adhere to recommendations of guidelines and strategies. However, it is necessary to establish whether and when the addition of an ICS to the LAMA/LABA combination is effective, to determine whether triple therapy can induce an additional clinical benefit over dual bronchodilation, irrespective of a preventive effect on COPD exacerbations, to establish its value, and to examine whether cost differences can support the use of triple therapy over combined LAMA/LABA therapy in real life.Keywords: dual bronchodilation, triple therapy, ICSs, LABs, LAMAs

In the circular economy, a closed-loop supply chain is essential to guarantee the logistics of raw materials to the correct destination of the end-of-life (EOL) product. This is magnified by hazardous products that can contaminate the environment, such as lead, as well as the people involved in their production processes. Through an exploratory study of multiple cases, we analyzed the Brazilian lead-based vehicle battery chain by investigating two main manufacturers, two recycling companies, and eight distributors/retailers. The aim of the study was to analyze the relationships between the actors in the lead acid battery chain and identify the mechanisms that induce recycling programs, and to propose an explanatory framework. The results indicate that although the sustainability strategies of OEMs are implemented by regulatory mechanisms, the impacts of these strategies cascade among all agents in the supply chain, promoting a convergence between actions and relationships between actors from the perspective of the triple bottom line, highlighting variables for each dimension (economic, social, and environmental). The study contributes to the consolidation of the triple bottom line concepts in the lead acid battery production chain and presents managerial implications for sustainability management. [ABSTRACT FROM AUTHOR]

This essay aims to provide an overview of the festivals dedicated to the analog films and performance practices of filmmakers and artist-run laboratories that posit themselves as media counter-culture and analog 'resistance'. Such events offer the films' material quality as a contrast to the planned obsolescence common in the IT industry. Currently, many filmmakers, artists and collectives create spaces, cooperatives, and independent labs to construct a media archaeology approach that is based on the experimental, hands-on re-enactment of traditional and obsolete practices. These film performance events thus exhibit the counter-cultural research performatively pursued by filmmakers, artists and collectives in an attempt to attract a perceptive audience capable of fully understanding this complex fruitive experience. [ABSTRACT FROM AUTHOR]

• We distinguish how sustainability-oriented labs approach sustainability in practice. • An empirically grounded typology is developed based on a prior systematic review. • Six types are identified, ranging from 1) Fix and control to 6) Explore and shape. • We present similarities between labs in each type, as well as differences across types. • The typology may function as a heuristic and frame for sustainability transitions praxis. Sustainability is high on the political agenda, with its analytical and practical importance underscored in the field of sustainability transitions. Experiments, arenas, and laboratories are frequently highlighted as real-world objects to investigate sustainability in place. Despite existing lab studies, attempts at comparison at the empirical level remain unconvincing. Here, sustainability remains oversimplified, warranting further investigation to unpack how labs compare in their orientation towards sustainability. This article presents a rigorous and transparent empirically grounded typology, intended to discern ways to engage with sustainability. We outline and elaborate upon six distinctive types entitled: 1) Fix and control, 2) (Re-)Design and optimize, 3) Make and relate, 4) Educate and engage, 5) Empower and govern, and 6) Explore and shape. This study highlights similarities and differences between labs, and across different types. These findings are discussed with reference to ongoing conceptualizations on directionality, providing a fruitful point of departure for ongoing transitions research. [ABSTRACT FROM AUTHOR]

Technological advancements in virtual reality have opened the door for widespread dissemination and application in engineering education. In surveying engineering, outdoor labs are essential, because they offer great means for experiential learning and preparation for real applications. However, challenges related to weather, inaccessibility to sites, transportation costs, and liability reduce time spent with instruments, and limit comprehension of surveying procedures and preparedness for the job market. Through virtual reality, we can create realistic surveying scenarios that are difficult to implement in practice, such as surveying in cities, at construction sites, and in different terrain scenarios. In addition, virtual reality can be used to support remote and online learning. This paper presents the thorough implementation of virtual reality labs in a surveying engineering first-year class. Technical feedback showed that surveying labs were recreated with a high level of fidelity, which is important to transfer skills learned in virtual reality to the real environment. Students stated that virtual reality gave them more incentives to learn, added to the fun of learning, and improved their overall learning experience. Furthermore, students indicated that virtual reality labs helped them understand surveying procedures and the operation of instruments, and they considered virtual labs to be a useful tool for preparation for physical labs. Pedagogical assessments using grades from previous years showed that the virtual reality labs enhanced student learning. Barriers of virtual reality, such as nausea and motion sickness, limit their extensive use. Despite a few negatives, virtual reality offers viable solutions to challenges in surveying engineering education, with the potential for further development and integration in other surveying courses. [ABSTRACT FROM AUTHOR]

This study investigates the emergence and the rise of Creative Hubs (CHs) in Istanbul, which as Turkey’s economic capital contains most of its creative workforce and the largest number of its CHs. In the last 10 years, the number of co-working spaces (CWSs), incubation centres (ICs), labs, and makerspaces in the city has rapidly increased, following a global trend. This study aims to better understand the changing working forms of the city by investigating the motivations behind the emergence of CHs. 46 CH examples, consisting of CWSs, ICs, makerspaces, and labs, have been examined for this purpose. The study is structured around the four main categories that highlight the different aspects of CHs: structure (establishment structure and community structure), focus (sectors and professions), services (physical and social facilities), and values (motivation). The findings of the study demonstrate that members of CHs are mostly freelancers, entrepreneurs, micro SMSs, and start-ups, consisting mostly of members of Generation Y. They work predominantly in creative sectors and tend to look for flexible and cost-saving solutions, support mechanisms, and new connections for their work. The research revealed that CHs are distinguished through the services that they provide. Having emerged as new forms to respond to the distinctive needs of emerging jobs in the creative economy era, they can be considered a new landscape of the post-industrial city.

Pain and obesity are frequently co-morbid health conditions; thus, it is unsurprising that pain is commonly experienced by individuals seeking bariatric surgery. While pain is generally reduced in the short-term after surgery, there is also variability in pain outcomes and less is known about how unresolved or recurring pain may relate to long-term weight loss and weight loss maintenance. This study evaluated trajectories of pain scores through 7 years following bariatric surgery and whether higher pain levels related to poorer weight loss and greater weight regain. Data were collected from 3 university hospitals, 1 private not-for-profit research institute, and 1 community hospital. Self-report measures of pain and weight change data were utilized for 1702 adults seeking Roux-en-Y gastric bypass surgery from the Longitudinal Assessment for Bariatric Surgery (LABS) cohort. A series of linear mixed models examined trajectories of pain scores and the concurrent predictive relationship between pain and weight outcomes from pre-surgery through 7 years post-surgery. Overall bodily-, hip-, and knee-pain improved through 2 years, deteriorated from 2–5 years, and then slightly improved from 5–7 years following surgery (P <.001). Greater pain was concurrently associated with less weight loss and greater weight regain over time (P ≤.006). Pain is evident in the long-term following bariatric surgery and associated with suboptimal weight outcomes. More research is needed to identify mechanisms underlying this relationship, which may ultimately help develop appropriate pain assessment and treatment strategies to ensure optimal post-surgery outcomes. • Pain is evident in the long term following bariatric surgery • Trajectories of pain show varying levels of improvement and deterioration over time • Greater pain is concurrently associated with less weight loss following surgery • Greater pain is concurrently associated with greater weight regain [ABSTRACT FROM AUTHOR]

We present here an evidence-based review of the utility, timing, and indications for laboratory test use in the domains of inflammation, cardiology, hematology, nephrology and co-infection for clinicians managing the care of hospitalized COVID-19 patients. Levels of IL-6, CRP, absolute lymphocyte count, neutrophils and neutrophil-to-lymphocyte ratio obtained upon admission may help predict the severity of COVID-19. Elevated lactate dehydrogenase, ferritin, aspartate aminotransferase, and ᴅ-dimer are associated with severe illness and mortality. Elevated cardiac troponin at hospital admission can alert clinicians to patients at risk for cardiac complications. Elevated proBNP may help distinguish a cardiac complication from noncardiac etiologies. Evaluation for co-infection is typically unnecessary in nonsevere cases but is essential in severe COVID-19, intensive care unit patients, and immunocompromised patients. Doctors managing the complex care of individuals with COVID-19 need timely evidence to guide which lab tests to send to predict outcomes and prevent and treat COVID-19 complications involving the heart, blood clots, the kidney, and other infections that occur during the hospital course. Several lab tests such as IL-6, CRP and white blood cell subset counts may help predict the severity of COVID-19 during the patient's hospital course if obtained when the patient first presents to the hospital. Other tests such as lactate dehydrogenase, ferritin and aspartate aminotransferase are also associated with severe illness and mortality but have less evidence for their utility beyond IL-6, CRP and other tests. A test related to blood coagulation, ᴅ-dimer, is also associated with COVID-19 severity, and it may be used if the patient is suspected of having a blood clot. Two heart biomarkers – cardiac troponin and proBNP – may help doctors diagnose and manage heart-related complications of COVID-19. Patients in the hospital with COVID-19 may be susceptible to other infections, but testing for these is most useful in patients with severe disease, such as those in the intensive care unit. Specific recommendations for testing for viral, bacterial and fungal infections are presented here. The judicious use of laboratory testing can help identify patients at high risk for severe or critical COVID-19 and aid in prevention, diagnosis and treatment of common COVID-19 complications. [ABSTRACT FROM AUTHOR]

In the circular economy, a closed-loop supply chain is essential to guarantee the logistics of raw materials to the correct destination of the end-of-life (EOL) product. This is magnified by hazardous products that can contaminate the environment, such as lead, as well as the people involved in their production processes. Through an exploratory study of multiple cases, we analyzed the Brazilian lead-based vehicle battery chain by investigating two main manufacturers, two recycling companies, and eight distributors/retailers. The aim of the study was to analyze the relationships between the actors in the lead acid battery chain and identify the mechanisms that induce recycling programs, and to propose an explanatory framework. The results indicate that although the sustainability strategies of OEMs are implemented by regulatory mechanisms, the impacts of these strategies cascade among all agents in the supply chain, promoting a convergence between actions and relationships between actors from the perspective of the triple bottom line, highlighting variables for each dimension (economic, social, and environmental). The study contributes to the consolidation of the triple bottom line concepts in the lead acid battery production chain and presents managerial implications for sustainability management.

• A serious escape game based on cards has been created for the preparation of stirring labs. • The implementation was successful: learners became autonomous, very efficient and were excited about the pedagogical game. • The game material is fully available in French and in English for use in other contexts. This paper presents feedback on the implementation of an educational escape game to replace the first hour of a 4 -h lab session. Two problems were encountered when teaching stirring in chemical engineering labs: on the one hand, learners had difficulties preparing calculations before practical work, as they were unable to find out by themselves how to calculate dimensionless numbers from measured quantities; on the other hand, manipulations during stirring labs are extremely easy or even boring: learners just have to implement the tank, vary the rotation speed, read the torque value, change the stirrer and start over. The goal of the educational escape game we have developed was to make the working data of the lab meaningful by preparing the lab session with the learners for one hour. We also wanted to make them autonomous during the lab session and make the stirring lab session less boring. With the introduction of this one-hour game, the lab session was reduced to three hours; this was not a problem however because -thanks to the game- the learners were much more efficient and got straight to the point during the practical work. The game "Carnivorous Yoghurts" is a card game, along the lines of popular domestic escape games, developed by one teacher and two pedagogical engineers. The implementation of this educational game was successful: the learners became totally autonomous, very efficient and they were excited about the game. The engineering skills of stirring labs are still acquired, probably in slightly greater depth thanks to the "flow" effect; traditional soft skills achieved during labs are strengthened (teamwork and communication) and new soft skills are acquired (cooperation and decision co-construction). [ABSTRACT FROM AUTHOR]

Carrot pickle is a traditional fermented food produced all over the world. The continuous fermentation during marketing and storage resulting in over acidification, softening, undesirable aroma, and color. This study was conducted to develop fermented vegetable pickle from carrot added with spices and salt (3.5%). The aim of the study was to investigate the effect of treatments such as microwave heating for 2.5, 3.5 and 4.5 min and sodium benzoate at concentrations 350, 450 and 550 ppm on desirable quality attributes such as microbial load (log10 cfu/gm, texture, Acidity (% lactic acid), pH, LABs and sensory attributes of fermented carrot pickle during storage period of 30 days. Results indicate that microwave treated samples showed decrease in pH value from 5.68 to 4.83, 5.75 to 4.85 and 5.63 to 4.34, respectively. Microwave treated carrot pickle also showed significantly lower microbial count and titratable acidity value than samples treated with sodium benzoate. Texture analysis also showed decrease in pickle firmness during storage, but sodium benzoate treated samples showed highest decline than microwave treated samples. Color analysis showed increase in L* value in all treated samples during entire storage than control. Sensory evaluation indicated significantly higher overall acceptability score for microwave treated sample (2.5 min) than control. From the present findings it is conclude that microwave treatment could be employed to extend the shelf life and preserve the organoleptic attributes of carrot pickle. [ABSTRACT FROM AUTHOR]

Background: The Ministry of Health in Côte d'Ivoire and the International Training and Education Center for Health at the University of Washington, funded by the United States President's Emergency Plan for AIDS Relief, have been collaborating to develop and implement the Open-Source Enterprise-Level Laboratory Information System (OpenELIS). The system is designed to improve HIV-related laboratory data management and strengthen quality management and capacity at clinical laboratories across the nation., Objective: This evaluation aimed to quantify the effects of implementing OpenELIS on data quality for laboratory tests related to HIV care and treatment., Methods: This evaluation used a quasi-experimental design to perform an interrupted time-series analysis to estimate the changes in the level and slope of 3 data quality indicators (timeliness, completeness, and validity) after OpenELIS implementation. We collected paper and electronic records on clusters of differentiation 4 (CD4) testing for 48 weeks before OpenELIS adoption until 72 weeks after. Data collection took place at 21 laboratories in 13 health regions that started using OpenELIS between 2014 and 2020. We analyzed the data at the laboratory level. We estimated odds ratios (ORs) by comparing the observed outcomes with modeled counterfactual ones when the laboratories did not adopt OpenELIS., Results: There was an immediate 5-fold increase in timeliness (OR 5.27, 95% CI 4.33-6.41; P<.001) and an immediate 3.6-fold increase in completeness (OR 3.59, 95% CI 2.40-5.37; P<.001). These immediate improvements were observed starting after OpenELIS installation and then maintained until 72 weeks after OpenELIS adoption. The weekly improvement in the postimplementation trend of completeness was significant (OR 1.03, 95% CI 1.02-1.05; P<.001). The improvement in validity was not statistically significant (OR 1.34, 95% CI 0.69-2.60; P=.38), but validity did not fall below pre-OpenELIS levels., Conclusions: These results demonstrate the value of electronic laboratory information systems in improving laboratory data quality and supporting evidence-based decision-making in health care. These findings highlight the importance of OpenELIS in Côte d'Ivoire and the potential for adoption in other low- and middle-income countries with similar health systems., (©Yao He, Yves-Rolland Kouabenan, Paul Henri Assoa, Nancy Puttkammer, Bradley H Wagenaar, Hong Xiao, Stephen Gloyd, Noah G Hoffman, Pascal Komena, N'zi Pierre Fourier Kamelan, Casey Iiams-Hauser, Adama Sanogo Pongathie, Alain Kouakou, Jan Flowers, Nadine Abiola, Natacha Kohemun, Jean-Bernard Amani, Christiane Adje-Toure, Lucy A Perrone. Originally published in JMIR Public Health and Surveillance (https://publichealth.jmir.org), 20.03.2024.)

This study investigates the emergence and the rise of Creative Hubs (CHs) in Istanbul, which as Turkey's economic capital contains most of its creative workforce and the largest number of its CHs. In the last 10 years, the number of co-working spaces (CWSs), incubation centres (ICs), labs, and makerspaces in the city has rapidly increased, following a global trend. This study aims to better understand the changing working forms of the city by investigating the motivations behind the emergence of CHs. 46 CH examples, consisting of CWSs, ICs, makerspaces, and labs, have been examined for this purpose. The study is structured around the four main categories that highlight the different aspects of CHs: structure (establishment structure and community structure), focus (sectors and professions), services (physical and social facilities), and values (motivation). The findings of the study demonstrate that members of CHs are mostly freelancers, entrepreneurs, micro SMSs, and start-ups, consisting mostly of members of Generation Y. They work predominantly in creative sectors and tend to look for flexible and cost-saving solutions, support mechanisms, and new connections for their work. The research revealed that CHs are distinguished through the services that they provide. Having emerged as new forms to respond to the distinctive needs of emerging jobs in the creative economy era, they can be considered a new landscape of the post-industrial city. [ABSTRACT FROM AUTHOR]

Abstract The effect of withdrawal rates on the dendrite growth and defects formation in the rejoined platforms of a Ni-based single crystal superalloy during directional solidification was studied by experimental investigations and ProCAST simulations. The results showed that the dendrite pattern in the rejoined platforms mainly comprised two regions: original primary dendrite region and lateral growth region. With increasing withdrawal rate, the lateral growth was more severe and the tendency of low angle grain boundaries (LABs) was greater because of dendrite deformation. Once the withdrawal rate exceeded 100 μm/s, local fragmentation appeared in the middle of the platforms and some ternary dendrites were detached from their parent dendrites. When the withdrawal rate was increased to 150 μm/s, lots of dendrite fragments formed and the integrity of single crystal was completely destroyed, which might be caused by the solute enrichment and was further promoted by the unstable growth conditions. Highlights • A model with rejoined platforms was designed, which was the sensitive site prone to casting defects. • Grain boundaries are easy to form in the rejoined platforms. • A new defect, fragmentation was discovered in the rejoined platforms and was reasonably explained. • The effect of withdrawal rates on the dendrite growth and defects formation in the rejoined platforms was investigated. [ABSTRACT FROM AUTHOR]