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Monosodium glutamate induces cellular stress, endoplasmic reticulum stress, mitochondrial dysfunction, and cell death in intestinal epithelial cells
No full textNovartis Research InstitutesNovartis Research Institute
Examining the instrumental formations of pre-service teachers in the process of making sense of different representations of algebraic expressions within a technological environment
Get PDFCebir öğretiminde teknolojinin kullanımı, öğrenme süreci üzerinde olumlu etkiler yaratmakta ve bu nedenle alanyazında önemli bir yer edinmektedir. Ancak, teknolojinin hangi aşamalarda ve ne ölçüde kullanılacağına karar vermek çoğu zaman öğretmenler ve araştırmacılar için bir zorluk oluşturmaktadır. Enstrümantal yaklaşım, bu zorluğun aşılmasında öğretmenlere ve araştırmacılara kuramsal bir çerçeve sunmaktadır. Bu çalışma, öğretmen adaylarının teknolojik ortamda cebirsel ifadeleri temsil etme süreçlerini ve bu süreçlerde ortaya çıkan enstrümantal oluşumlarını incelemeyi amaçlamaktadır. Bu kapsamda, kağıt-kalem ve dinamik geometri ortamlarında cebirsel ifadelerin yazımı ve grafiklerinin çizimine yönelik geliştirilen enstrümanlı eylem şemalarına odaklanarak, öğretmen adaylarının matematik öğretimine yönelik teknolojik araçların öğretim sürecindeki katkısı değerlendirilmiştir. Araştırma, aynı zamanda öğretmen adaylarının cebirsel kavramları anlamlandırma süreçlerine ve teknoloji kullanımının bu süreç üzerindeki etkilerine ilişkin önemli bulgular sunmayı hedeflemektedir. Aynı zamanda, öğretmen adaylarının sınıf ortamında cebirsel ifadelerin yazımı ve grafiklerinin çizimi için programın kazanımlarına uygun teknoloji destekli etkinlikleri içeren bir öğretim deneyimi tasarlanmıştır. Bu tez çalışması, bu öğretim süreci sonrasında öğretmen adaylarının elde edilen enstrümanlı eylem şemalarını ortaya koymaktadır. Çalışmada kullanılan teknolojik araç, dinamik geometri yazılımı Cabri-Geometri yazılımıdır. Bursa Uludağ Üniversitesi ilköğretim matematik öğretmenliği programı 2. sınıfta eğitim gören öğretmen adayları ile gerçekleştirilen çalışmada, cebir, cebirsel ifadeler ve grafikleri ile ilgili farklı türde aktiviteler yazılı ve sözlü görüşmeler, çalışma yaprakları, ses kayıtları ve ekran kayıtları kullanılmıştır. Çalışmadan elde edilen veriler içerik analiz yöntemi ile analiz edilmektedir. Bunu gerçekleştirmek için öncelikle derslerde çalışma yapraklarından elde edilen ses kayıtları yazıya dökülmüştür, yazılı görüşmeler ve ek olarak, seçilen öğrencilerle yapılan sözlü mülakatlarda kaydedilen ses kayıtları ile karşılaştırılarak dökümü yapılmıştır. Daha sonra elde edilen veriler ile kategorilere ayrılmış ve enstrümantal yaklaşımın bileşenleri doğrultusunda temalar oluşturulmuştur. Oluşturulan temalar enstrümanlı eylem şemalarının daha net anlaşılabilmesi adına gerek görüldüğü yerlerde birleştirilip ya da ayrıştırılmıştır ve elde edilen son temalar araştırmanın amacı doğrultusunda yorumlanmaktadır.The integration of technology into algebra instruction has been shown to positively impact the learning process and has therefore gained considerable attention in the literature. However, deciding at which stages and to what extent technology should be incorporated often presents a challenge for both teachers and researchers. The instrumental approach offers a theoretical framework that helps address this challenge by providing insights into the relationship between users and technological tools. This study aims to examine the instrumental formations of preservice teachers as they engage in representing algebraic expressions within a technological environment. Specifically, it focuses on the instrumental action schemes developed during the writing and graphing of algebraic expressions in both paper-and-pencil and dynamic geometry environments. By doing so, the study evaluates the contribution of technological tools to the mathematics teaching process. Additionally, the research seeks to reveal important findings concerning the meaning-making processes of algebraic concepts by pre-service teachers and the influence of technology on these processes. To support this goal, a teaching experiment was designed that includes technology-supported activities aligned with curriculum objectives, aiming to support the writing and graphing of algebraic expressions in classroom settings. This dissertation presents the instrumental action schemes that emerged after the implementation of this instructional process. The technological tool used in the study is the dynamic geometry software Cabri-Geometry. The study was conducted with second-year students enrolled in the elementary mathematics teacher education program at Bursa Uludağ University. A variety of algebra-related activities were implemented using written and oral interviews, worksheets, audio recordings, and screen recordings. The collected data were analyzed using content analysis. First, the audio recordings obtained from classroom sessions were transcribed. These transcripts were then compared and cross-referenced with written interviews and additional oral interviews conducted with selected participants. The data were subsequently categorized, and themes were generated based on the components of the instrumental approach. In order to improve the clarity and interpretability of the instrumental action schemes, the themes were either merged or separated where necessary. The final themes were interpreted in line with the objectives of the study
Impact of seasonal variation and transportation distance on welfare and economic parameters in broiler breeder chickens during transit to slaughterhouses
No full text1. Transporting animals under inappropriate conditions causes pain and suffering to the animals and causes financial loss for the producers. This study investigated the effects of the season and transportation distance on the dead-on-arrival (DOA), reject rate (due to lesions and damage) and body weight loss parameters of the broiler breeder (BB) chickens during transportation from the farm to the slaughterhouse.2. Data was obtained by analysing two-year records of a commercial slaughterhouse in Turkey. During the period examined, 2,452,624 BB were transported and slaughtered to this slaughterhouse by 554 trucks.3. The lowest DOA rate (0.186%) occurred in the summer season and the reject rate in summer (0.104%) was lower than in other seasons. During the monitored period, the effect of season on body weight loss was not statistically significant. When the impact of transportation distance was considered, there was more body weight loss (1.663%) in animals transported over longer distances.4. The data highlighted how important it is to pay attention to transportation conditions of these animals to the slaughterhouse, especially under cold climate conditions and over long distances, both in terms of animal welfare and economics
Structuring fermented dairy functionality: Technological simulation of artisanal and industrial ayran-buttermilk models for optimized quality and sensory integrity
No full textFermented milk beverages, particularly those with strong geographical identity, are attracting increasing interest due to their versatile nutritional, sensory, and functional profiles. This study presented a systematic comparison between two production strategies applied to a regional yogurt-based beverage. Both batches were subjected to parallel production workflows and evaluated for physicochemical composition, antioxidant potential, mineral content, rheological behavior, color indices, and sensory performance during 14 days of refrigerated storage. The batch processed under conditions simulated with artisanal products exhibited superior dry matter content, higher mineral levels (especially Na, K, Ca, and P), and significantly higher total phenolic and flavonoid concentrations. These improvements were associated with enhanced antioxidant activity and denser microstructural integrity. Furthermore, rheological and textural analyses revealed a creamier mouthfeel, more stable foam, and balanced viscosity in these samples. Sensory evaluation revealed a clear preference for the artisanal-inspired batch in terms of visual appeal, aroma richness, and flavor-body harmony. In contrast, industrial samples benefited from better control of fermentation kinetics and standardized milk composition, resulting in better protein stability and consistent color characteristics. These results highlight the feasibility of adapting traditional fermentation principles to scalable industrial frameworks without compromising technological, functional, or sensory parameters. This research provides valuable insights for functional dairy innovation by highlighting the structural, nutritional, and hedonic interactions in fermented milk systems, combining artisanal originality with industrial applicability
The effect of web-assisted guided inquiry approach on students' systems thinking skills
Get PDFIn parallel with technological developments, learning-teaching environments have changed and students are active and responsible for their own learning throughout the process. It is believed that the design of enriched teaching materials based on web-assisted and inquiry-based learning approaches will be important in terms of learning-teaching environments. The aim of this study is to investigate the effect of web-assisted guided inquiry approach in science education on students' systems thinking skills. An embedded mixed methods design was used in this study. First, materials were developed for the systems in our body unit and three teachers used these materials in their classrooms. A total of 155 sixth grade students participated in the study. In the experimental group the lessons were taught according to the web-assisted guided inquiry approach, while in the control group the lessons were taught according to the science curriculum. The systems thinking skills test was used as a quantitative data collection tool and observations, student journals, and interviews were used as qualitative data collection tools. As a result of the research, it was found that there was a significant difference in the systems thinking skills of the students in the experimental group compared to the control group [F(1,152) = 12.23, p < 0.05]. It can be said that the change in systems thinking skills was due to establishing a relationship between concepts, looking at events holistically and understanding how the system can change with the disappearance or addition of a variable in the system
Biologically informed decision-öaking for PMRT in pT3N0M0 luminal breast cancers (Protocol MF22-02): International multicenter real-world data
No full textBackground: Current guidelines do not list definitive recommendations for postmastectomy radiation therapy (PMRT) in patients with luminal pT3N0M0 breast cancer (BC). Increased data suggests de-escalation of radiation therapy (RT) in genomically defined biologically favorable luminal BCs. The goal of this study is to determine whether PMRT can be safely omitted for this specific subgroup of patients. Methods and materials: Two hundred and 2 women from 16 centers with pT3N0M0 hormone receptor (HR) positive, HER2 negative BC who underwent mastectomy were retrospectively analyzed. No patients received neoadjuvant chemotherapy. Three patients were excluded because of positive surgical margins. Patients were divided into 2 groups: PMRT (n = 130) and no PMRT (n = 69). Groups were compared in terms of overall survival (OS), loco-regional recurrence (LRR) rate, and distant metastases (DM) in light of the Magee Equations Score (MS), menopausal status/age, axillary surgery, pathology, lymphovascular invasion (LVI), adjuvant chemotherapy, and adjuvant endocrine therapy. Results: The majority of the patients had invasive ductal carcinoma (49%, n = 98). There was no significant difference regarding tumor size, axillary surgery, and adjuvant endocrine therapy between the 2 groups (P = .82, P = .28, P = .12, respectively). LVI was 19% (n = 39), and it was greater in the PMRT group (25% vs. 10%; P = .01). Patients in the PMRT group received more chemotherapy (66% vs. 30%; P < .001), had more grade 3 tumors (28% vs. 9%, P = .005), and were more premenopausal (49% vs. 22%; P = .0001). At a median follow-up of 51.3 months for the no PMRT group and 65.9 months for the PMRT group (P = .041), 9% (n = 6) of patients from the no PMRT group and 2% (n = 3) from the PMRT group developed LRR (P = .047). There was no difference in local recurrence (1% in no PMRT group vs. 2% in PMRT group; P = .7) and distant recurrence (7% in no PMRT group vs. 3% in PMRT group; P = .16) in patients who received PMRT and no PMRT. Further comparison of the LRR in the no PMRT and PMRT groups in patients with an MS < 18 did not show a significant difference (3% vs. 4%; P = .64). However, among patients with an MS ≥ 18, no PMRT group had a higher LRR rate compared to the PMRT group (11% vs. 2%; P = .01). In patients with an MS ≥ 18, the administration of PMRT correlates with statistically significantly better LRR-free survival (HR 0.19; 95% CI 0.05-0.79; P = .02). Conclusions: Our findings imply that when considering PMRT for patients with pT3N0M0, HR-positive, and HER2-negative BC, clinicians can benefit from a combination of pathological risk factors and recurrence prediction models. Patients with MS < 18 experience a comparable rate of recurrence irrespective of PMRT, while those with MS ≥ 18 have higher rates of LRR and thus should not omit PMRT
Spider wasp optimizer-based PID control approach for temperature management in continuous stirred tank reactors
No full textTemperature control in continuous stirred tank reactors (CSTRs) poses a significant challenge due to the inherent nonlinearity of the process and the presence of time delays. These complexities often result in unstable and inefficient performance of traditional control systems. In this paper, a novel approach based on optimizing a PID-F controller using the spider wasp optimizer (SWO) is proposed to address temperature management in CSTRs. This method leverages SWO's computational capabilities to finely tune the controller parameters, effectively overcoming the challenges of nonlinearity and time delays. To implement this solution, the CSTR's mathematical model was linearized and approximated as a stable first-order plus time delay (SFOPTD) model. The performance of SWO in optimizing the PID-F controller was then compared with other established algorithms (CFOA, FLA, and MPA) through simulation studies. Simulation results demonstrate that the proposed SWO-based approach achieves a minimum rise time (0.0126 s), the lowest overshoot (0.1249%), and a fast settling time (0.0645 s). These outcomes highlight SWO's superior performance over competing algorithms, underscoring its potential for industrial applications in CSTR control
Assessing processes and results of living labs: Toward a general framework
No full textLiving labs (LLs) have gained recognition as a research method for addressing complex sustainability challenges. They have been applied to diverse topics such as climate-change mitigation, reductions in the use of fossil fuel, and resilience in agri-food systems. Despite the increasing application of LLs, the assessment of their results remains inconsistent, primarily due to the heterogeneity of projects and methodologies. Through a systematic literature review, we uncover how different LLs-focused on transformative environmental outcomes such as achieving a low-carbon society-are assessed. This analysis reveals different tensions in how assessments are carried out, along with blind spots. We propose the Theory of Change (ToC) as a promising approach to address the limitations in current LL evaluation methods. ToC models explicitly distinguish between short-, medium-, and long-term objectives, clarifying essential goals and preventing the confusion of differing time horizons. ToC also helps manage the tradeoff between broad multi-stakeholder involvement and significant co-creation, allowing stakeholders to pursue objectives at different scales and time horizons. We build on ToC and insights from the literature review to propose a framework for assessing LLs as a social change method that integrates stakeholders' perspectives and values, facilitates systematic evaluation, and fosters meaningful co-creation. Adopting a tailored ToC approach for LLs could contribute to assessing transformative sustainability outcomes more effectively
Microstructure and mechanical properties of dissimilar resistance spot welds of tbf and hsla300 steel sheets
No full textThe welding behavior of the resistance spot welded dissimilar TBF-HSLA300 steel joints under different welding parameters was investigated. TBF steels were used as galvanized or ungalvanized. Microstructural characterization and mechanical tests were performed. Higher heat input resulted in the higher possibility of shrinkage cavities at the weld nugget and also increased the risk of liquid metal embrittlement (LEM) crack in the heat affected zone (HAZ) on galvanized TBF steel sheets. A partial melting zone was observed on HSLA300 side. The welds with ungalvanized TBF sheets had the higher nugget size and indentation. The highest hardness values (over 500 HV0.1) were observed in HAZ on TBF side. The lowest hardness values (below 300 HV0.1) on TBF side were observed in a very narrow softening zone between tempered zone and base metal. The fractures of all spot welds in the tensile shear test occurred on the TBF steel side with the thinner thickness. Low-strength steel sheet have to be sufficiently thicker in order to achieve higher welding strength. Higher welding time led to higher weld strength in the ungalvanized TBF combination. In the galvanized TBF combination, higher heat input led to the drastic decrease in weld strength due to LEM cracks.Beyçelik Gestamp A.Ş
A novel hybrid technique for enhancing mechanical properties in additively manufactured steels
Get PDFThis study introduces a novel hybrid manufacturing technique that combines Selective Laser Melting (SLM) with powder metallurgy to enhance the mechanical performance of steel lattice structures. The method involves fabricating shell-lattice components using SLM with 316 L, MS1, and 316 L + 2% Cu powders, followed by targeted sintering and heat treatment to refine the internal porous zones. Three distinct lattice geometries-closed hexagon, re-entrant, and Schwarz-P-were integrated into the design to examine structural behavior under compression. Parts were produced and tested using micro-hardness analysis, scanning electron microscopy, and compression testing. The sintering stage promoted densification and metallurgical bonding within the lattice-filled cavities, resulting in improved mechanical strength and multifunctionality. Results revealed yield strength improvements of up to 250% and toughness increases of 25%, particularly in re-entrant lattices. The technique also enabled the formation of multifunctional zones within a single part, including sintered porous regions, load-bearing lattice walls, and a dense outer shell. These findings demonstrate the potential of the hybrid method to produce lightweight, impact-resistant steel components more efficiently, with strong implications for aerospace, automotive, and defense applications