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The production of phycobiliproteins, such as cyanobacterial phycocyanins, is a growing interest due to their diverse industrial and biotechnological applications. This study focuses on optimizing phycocyanin production using the strain Potamosiphon sp. through experimental techniques and mathematical modeling in fed-batch cultures. The methodology applied includes determining the kinetic constants by linearizing the Monod equation evaluating the concentrations of biomass, C-phycocyanin (C-PC), nitrates (NO3), and phosphates (PO4). A mathematical model of periodic fed-batch feeding was subsequently established, applying mass conservation principles and evaluating the accuracy of the Monod, Contois, Moser, and Tessier models. The results indicate that phycocyanin production is highly dependent on phosphorus and nitrogen concentrations, with optimal conversion observed at specific levels of these elements (0.832 for phosphorus and 0.805 for nitrogen in terms of C-PC and biomass, respectively). The Tessier model demonstrated the highest accuracy in predicting production and optimizing operational conditions, with a Mean Squared Error (MSE) of 0.005000 for biomass production, 0.200000 for C-PC production, and 0.000010 for substrate consumption. It also achieved high R² values of 0.980 for biomass, 0.999 for C-PC production, and 0.997 for substrate consumption. It presented the lowest Akaike Information Criterion (AIC) scores, indicating its robustness and reliability in modeling these processes and manipulating cultivation conditions and providing adequate nutrition allowed for achieving growth rates of 1.23 g/L and a C-PC concentration of 37 mg/L, which are essential for industrial applications such as natural colorants and antioxidants, among others.

This descriptive qualitative study explores factors contributing to research hesitancy and limited research engagement experienced by Filipino beginning teachers. By employing in-depth individual interviews and a virtual focus group discussion, the study gathered insights from 21 purposively selected beginning teachers. Participants were required to meet all inclusion criteria to be part of the study. Template analysis was used to interpret the data gathered. The participants highlighted poor research foundations, demanding work conditions, lack of mentoring, perceived lack of professional competence, and preoccupation with personal issues as factors contributing to their research hesitance and limited research engagement. A significant finding revealed that many beginning teachers are preoccupied with personal issues, which often hinder their ability to balance personal and professional responsibilities. This highlights the complex interplay between personal struggles and professional challenges that novice educators face, an underexplored area in research. Studying the topic qualitatively allowed for a deeper understanding of these various challenges, bringing to light personal and professional struggles that may not have been fully captured through quantitative methods alone, providing a more complete picture of the issue. Findings also suggest a need for targeted interventions, such as enhanced research instruction, structured mentoring systems, manageable teaching responsibilities, and in-service training, to empower and support beginning teachers in their research journey. This study has significant implications for teacher preparation programs and school administrators, aiming to foster a research-oriented culture and enhance research engagement among early-career educators. Further investigation into how personal issues affect research skills development could help design more effective support strategies.

This study addressed the optimization of biomass and C-phycocyanin (C-PC) concentration and its purity in the thermotolerant cyanobacterium Potamosiphon sp by adjusting key light quality parameters. Custom design and Central Composite Design experimental designs were employed, using LEDs light intensity, wavelength, and photoperiod. The results demonstrated that these lighting parameters significantly influence biomass and C-phycocyanin production, achieving up to a 100 % increase in phycocyanin accumulation and biomass production and a 50 % improvement in purity index compared to conventional white light under optimal conditions of Red:Blue light (3:1), Intensity (283 μmol m−2 s−1), and photoperiod (17.8 H light). The findings support the use of specific LEDs wavelengths that optimize the performance of production processes and the quality of products derived from cyanobacteria, such as high-value phycobiliproteins.

This qualitative study explores the decision-making processes of deans in teacher education in the Philippines and investigates the challenges they encounter. The research employs a descriptive qualitative approach grounded in the interpretive paradigm, focusing on the experiences and perspectives of current and former deans. Data were collected through interviews, focus group discussions, and reflective essays, with thematic analysis used for data interpretation. Findings reveal key issues necessitating strategic decisions, including performance in licensure exams, introduction of new programs, accreditation demands, inherent functions, and faculty development programs. The identified key issues impact institutional quality, accreditation, and faculty competence. This study underscores the significance of strategic decision-making in teacher education leadership and administration, offering insights for educational policymakers, administrators, and stakeholders. By shedding light on these aspects, this study contributes to continuous improvement in teacher education and the broader educational landscape, aligning with evolving societal needs.

This study presents a comprehensive bibliometric analysis of research on bank erosion and control measures, utilizing the Scopus database and VOSviewer software. Key terms such as “bank”, “erosion”, “control”, and “protection” frequently appear in the literature, underscoring their importance in studies on riverbank erosion. Since 2000, scientific production has steadily increased, particularly in disciplines such as Environmental Sciences and Earth and Planetary Sciences, driven by growing concerns about climate change and sustainable water resource management. Countries with substantial research resources, such as the United States and China, lead in the production of studies, reflecting their commitment to addressing this global issue. In parallel, the evaluation of erosion mitigation practices in Colombia revealed that, although effective techniques such as gabion walls and riparian vegetation exist, 40% of respondents do not implement specific measures. This lack of implementation is attributed to insufficient knowledge, limited resources, and misconceptions about the effectiveness of these techniques. The findings highlight the need to promote proven practices and enhance professional training. Future research should focus on developing more accurate predictive models, integrating interdisciplinary approaches, and assessing the impacts of climate change on bank erosion. Addressing barriers to applying effective techniques at the local level and improving access to resources and knowledge are critical steps to reducing bank erosion and ensuring sustainable water management.

We recently determined that Eq. (55), one of the equations reporting the implementation of current-density corrected metageneralized gradient approximation (cMGGA) density functionals in Ref. 1, is missing a multiplicative factor of 1/2. The correct equation reads(Equations Presented).While the other equations contained in the publication are unaffected by this error, the cMGGA excitation energies and optical rotations (ORs) should be replaced by the values reported below and provided in the updated supplementary material of Ref. 1. While some of the changes are significant, the conclusions of the paper still hold after the correction of these values. The original implementation in TURBOMOLE2 was corrected accordingly and has been released in version V7.6. One of us (J.L.) independently confirmed the implementation of Eq. (55). This implementation is part of Q-Chem version 5.4.3 a. AEX benchmark. Comparing the previous and present current-dependent implementations for cTPSS and cTPSSh over the entire AEX benchmark, the correction resulted in a shift to larger excitation energies by 0.03 eV on average, although the largest change was ~0.2 eV for the 3? state of NH. The correction tends to reduce the effect of the current-dependence and hence leads to slightly larger excitation energies than originally reported. For pyridone–lactam and OMpCA, the values reported in 2012 were too large due to a convergence issue, and the corrected values of the excitation energies display an even smaller effect of including the current-density response than the originally reported ones, in line with the other singlet excitations included in the AEX test set. The statistical error analysis for TPSS, TPSSh, cTPSS, and cTPSSh compared to experiment shows a slight change due to the corrections; see Table II (corrected) and Table III (corrected). Individual results for the benchmark set using cTPSS and cTPSSh are available in the corrected supplementary material of Ref. 1. b. Optical rotations. The corrected ORs are displayed in Table IV (corrected). The current-free results were re-confirmed except for two cases whose ground-state solution was not fully converged. As in the original publication, all results were computed in units of deg [dm(g/cc)]-1, utilizing the length gauge, and obtained at the sodium D-line of 589.3 nm. The effect of the corrections is small for most systems considered here, with the exception of bisnoradamantan-2-one, whose (c)TPSS ORs are significantly more negative than reported previously, while the hybrid results for (c)TPSSh are slightly more positive. The overall conclusion that cMGGAs provide(Table Presented).ORs with an accuracy comparable to that of GGAs remains unaffected. c. Testing strategy. We briefly outline a method to help ascertain the correctness of MGGA and cMGGA implementations using the one- and two-electron limit and an existing GGA implementation. By construction, the generalized Kohn–Sham kinetic energy density ˆt, Eq. (14), reduces to the von Weizsäcker kinetic energy density in the limit of one-electron systems and two-electron singlets. Thus, the substitution(Equations Presented).to the corresponding cMGGA one in this limit. While the resulting GGA generally yields KS potentials, virtual orbitals, and orbital rotation Hessians different from the MGGA and cMGGA ones, the total energy, density, and all properties derived from them are identical. In particular, the above substitution enables the calculation of cMGGA excitation energies for one-electron systems and two-electron singlets using a GGA code. Additional tests performed included the calculation of the second-order correction of the MGGA excitation energy treating the current density response as a perturbation and the calculation of the velocity form of the transition dipole moment µ0n,v from the integration of the transition current density on the molecular integration grid and the (converged) excitation energy O0n according to (Table Presnted).

Infectious diseases have significantly shaped human history, leading to significant advancements in medical science. The discovery and development of antibiotics represented a critical breakthrough, but the rise of antibiotic-resistant pathogens now presents a serious global health threat. Due to the limitations of current synthetic antimicrobials, such as toxicity and environmental concerns, it is essential to explore alternative solutions. Algae, particularly microalgae and cyanobacteria, have emerged as promising sources of bioactive antimicrobial compounds. This review provides a comprehensive analysis of the antimicrobial properties of algal-derived compounds, including polysaccharides, fatty acids, and phenols, which have shown effectiveness against multi-drug-resistant bacteria. A co-occurrence bibliometric analysis using VOSviewer highlighted five key research clusters: antibiotic resistance, algal extracts, biosynthesis, water treatment, and novel pharmacological compounds. Furthermore, the primary mechanisms of action of these bioactive compounds, such as the inhibition of protein synthesis and cell membrane disruption, were identified, demonstrating their potential against both common and multi-resistant pathogens. Future research should prioritize optimizing algal biomass production, utilizing genetic and metabolic engineering, and creating innovative delivery systems to enhance the efficient production of bioactive compounds. [ABSTRACT FROM AUTHOR]

The biosynthesis of silver nanoparticles (AgNPs) presents an innovative and sustainable approach in nanotechnology with promising applications in fields such as medicine, food safety, and pharmacology. In this study, AgNPs were successfully synthesized using the probiotic strain Lacticaseibacillus rhamnosus (BCRC16000), addressing challenges related to stability, biocompatibility, and scalability that are common in conventional nanoparticle production methods. The formation of AgNPs was indicated by a color change from yellow to brown, and UV–visible spectrophotometry confirmed their presence with a characteristic absorption peak at 443 nm. Furthermore, Fourier transform infrared (FTIR) spectroscopy revealed the involvement of biomolecules in reducing silver ions, which suggests their role in stabilizing the nanoparticles. In addition, field emission scanning electron microscopy (FE-SEM) showed significant morphological and structural changes. At the same time, dynamic light scattering (DLS) and zeta potential analyses provided valuable insights such as average size (199.7 nm), distribution, and stability, reporting a polydispersity index of 0.239 and a surface charge of −36.3 mV. Notably, the AgNPs demonstrated strong antibacterial activity and photocatalytic efficiency, underscoring their potential for environmental and biomedical applications. Therefore, this study highlights the effectiveness of Lacticaseibacillus rhamnosus in the biosynthesis of AgNPs, offering valuable antibacterial and photocatalytic properties with significant industrial and scientific implications. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive bibliometric analysis of research on bank erosion and control measures, utilizing the Scopus database and VOSviewer software. Key terms such as "bank", "erosion", "control", and "protection" frequently appear in the literature, underscoring their importance in studies on riverbank erosion. Since 2000, scientific production has steadily increased, particularly in disciplines such as Environmental Sciences and Earth and Planetary Sciences, driven by growing concerns about climate change and sustainable water resource management. Countries with substantial research resources, such as the United States and China, lead in the production of studies, reflecting their commitment to addressing this global issue. In parallel, the evaluation of erosion mitigation practices in Colombia revealed that, although effective techniques such as gabion walls and riparian vegetation exist, 40% of respondents do not implement specific measures. This lack of implementation is attributed to insufficient knowledge, limited resources, and misconceptions about the effectiveness of these techniques. The findings highlight the need to promote proven practices and enhance professional training. Future research should focus on developing more accurate predictive models, integrating interdisciplinary approaches, and assessing the impacts of climate change on bank erosion. Addressing barriers to applying effective techniques at the local level and improving access to resources and knowledge are critical steps to reducing bank erosion and ensuring sustainable water management. [ABSTRACT FROM AUTHOR]

Ants belonging to the genus Solenopsis are highly significant invasive pests worldwide. The control of these insects has historically relied on the use of synthetic insecticides, which, unfortunately, has led to a range of ecological repercussions. In light of these challenges and the limited availability of registered products for managing these pests, our study set out to synthesize and assess the insecticidal properties of carvacrol derivatives. The lethal and sublethal effects caused by these derivatives were compared to the essential oil of Lippia gracilis (50.7% carvacrol) and to the base molecule—carvacrol. Carvacryl benzoate was the most toxic derivative to Solenopsis sp., with an LD50 of 3.20 μg/ mg. This compound was about 2 and 7.6 times more toxic than carvacrol at the doses needed to kill 50 and 90% of populations, respectively. The workers of Solenopsis sp. showed a rapid reduction in survival when exposed to carvacrol (LT50 = 8.43 h) and carvacryl benzoate (LT50 = 8.87 h). Insects treated with sublethal doses of the compounds did not show significant effects on self-cleaning, allogrooming and aggregation, with the exception of those treated with L. gracilis essential oil. The oil increased self-cleaning and reduced allogrooming and aggregation. Ants treated with carvacrol and carvacryl benzoate travelled greater distances and had higher movement speeds when compared to the control. These compounds exhibited decreased meanders and angular velocities. When live workers were exposed to dead individuals at the LD90 of the compounds, carvacryl benzoate was the derivative that most reduced survival due to horizontal transfer. These findings underscore the considerable potential of carvacrol derivatives, specifically carvacryl benzoate, as an alternative approach to managing ants of the Solenopsis genus.

This study investigates the influence of photoperiod and wastewater concentration on the growth of microalgae and cyanobacteria for the removal of environmentally significant parameters (COD, BOD, Cr, Fe, color, chlorides, nitrogen compounds, and phosphates) from dyeing wastewater. A two-factor central composite design with surface response was employed, involving two algae species (Chlorella and Scenedesmus sp.) and two cyanobacteria species (Hapalosiphon and Oscillatoria sp.). The findings indicated that extended photoperiods (>13 h) and higher wastewater concentrations (70–80% v/v) enhanced biomass production across all strains. However, Hapalosiphon and Chlorella sp. (1.6 and 0.45 g/L) exhibited better tolerance to the wastewater’s high toxicity, resulting in higher biomass concentrations and improved COD and BOD removal by Hapalosiphon sp. (75% and 80%, respectively). Further analysis of the obtained biomass revealed their potential applications. Among the cyanobacteria, Hapalosiphon sp. synthesized the highest concentrations of total proteins and lipids (38% and 28% w/w, respectively), while Oscillatoria sp. displayed a high protein content (42% w/w). In contrast, the algae demonstrated a strong propensity for storing substantial quantities of total carbohydrates (65% and 57% w/w for Scenedesmus and Chlorella sp., respectively). These results signify the feasibility of cultivating photosynthetic microorganisms in industrial dyeing wastewater as a sustainable source of nutrients for targeted metabolite production.

As climate change progresses, there is an increasing interest on the use of non-conventional water sources such as brackish or saline waters. Nowadays, the main threat in Europe detected in these waterbodies is nitrate contamination. Within the multiple available methods studied for nitrate reduction, photocatalysis presents promising results, but this technology has not yet been tested in saline water. This work tackles the elimination of nitrate ([NO3−] =50 mg/L) in brackish and saline water ([sea salt] = 5–33 g/L) using ilmenite as photocatalyst and oxalic acid as an environmental-friendly reducing agent. The main challenge when working in saline water is to overcome oxalic acid scavenging by Ca2+ present in the water matrix. This can be solved either working at over stoichiometric concentrations of oxalic acid (≈300% stoich. dose) or acidifying the reaction media. The addition of hydrochloric acid ensures the protonation of oxalic acid, reducing drastically its precipitation as CaC2O4. Working at [C2O42−] = 180 mg/L, [FeTiO3] = 450 mg/L and [HCl 37%] = 13 mM, 73% total nitrogen (TN) elimination was reached after 420 min. Reaction temperature was also evaluated in the range of 20–80 °C, which allowed to calculate the Ea=9.8 kJ/mol. Finally, the effect of dissolved O2 on the TN reduction was assessed. Overall, photocatalytic nitrate reduction presents itself as a feasible technology regardless of the water salinity.

Leaf-cutting ants are important pests of agricultural and forest crops. Currently, few insecticides are registered for the control of these insects. Natural bioactive molecules can serve as models for the synthesis of new insecticidal compounds. Such ant killer products must be sustainable and efficient, considering not only lethal effects, but also sublethal effects, which can interfere with behavior and communication between colony members. In this study, we analyzed the toxicity of the monoterpene thymol and its derivatives, as well as the sublethal effects of these compounds on the behavior of the leaf-cutting ant Acromyrmex balzani. These effects were compared with the conventional synthetic insecticide deltamethrin. Although deltamethrin showed higher toxicity (LD50 = 0.87 × 10−5 µg/mg), all other tested compounds increased ant mortality, with thymyl chloroacetate being the most toxic derivative (LD50 = 1.41 µg/mg), followed by thymol (LD50 = 2.23 µg/mg). These three most toxic compounds interfered differentially in the behavior of ants. Thymyl chloroacetate caused increased self-cleaning and reduced allogrooming, which may be related to an attempt to avoid contamination between nestmates. In general, thymol caused greater avoidance among ants, reduced walking speed and caused disorientation in workers. On the other hand, thymyl chloroacetate (LD30) considerably increased the walking speed of the group, without changing the orientation of the individuals. Such changes may interfere with basic activities such as foraging and altering colony cohesion via different mechanisms. Thus, despite the desirable effects of deltamethrin on ant control, this insecticide is highly toxic and should be discontinued soon. Our results show that thymol and its structural modification in thymyl chloroacetate may represent potential ant killers to be used in the management of A. balzani.

Background & aimsThere is controversy regarding the role of the type 2 immune response in the pathogenesis of ulcerative colitis (UC)-few data are available from treatment-naive patients. We investigated whether genes associated with a type 2 immune response in the intestinal mucosa are up-regulated in treatment-naive pediatric patients with UC compared with patients with Crohn's disease (CD)-associated colitis or without inflammatory bowel disease (IBD), and whether expression levels are associated with clinical outcomes.MethodsWe used a real-time reverse-transcription quantitative polymerase chain reaction array to analyze messenger RNA (mRNA) expression patterns in rectal mucosal samples from 138 treatment-naive pediatric patients with IBD and macroscopic rectal disease, as well as those from 49 children without IBD (controls), enrolled in a multicenter prospective observational study from 2008 to 2012. Results were validated in real-time reverse-transcription quantitative polymerase chain reaction analyses of rectal RNA from an independent cohort of 34 pediatric patients with IBD and macroscopic rectal disease and 17 controls from Cincinnati Children's Hospital Medical Center.ResultsWe measured significant increases in mRNAs associated with a type 2 immune response (interleukin [IL]5 gene, IL13, and IL13RA2) and a type 17 immune response (IL17A and IL23) in mucosal samples from patients with UC compared with patients with colon-only CD. In a regression model, increased expression of IL5 and IL17A mRNAs distinguished patients with UC from patients with colon-only CD (P = .001; area under the receiver operating characteristic curve, 0.72). We identified a gene expression pattern in rectal tissues of patients with UC, characterized by detection of IL13 mRNA, that predicted clinical response to therapy after 6 months (odds ratio [OR], 6.469; 95% confidence interval [CI], 1.553-26.94), clinical response after 12 months (OR, 6.125; 95% CI, 1.330-28.22), and remission after 12 months (OR, 5.333; 95% CI, 1.132-25.12).ConclusionsIn an analysis of rectal tissues from treatment-naive pediatric patients with IBD, we observed activation of a type 2 immune response during the early course of UC. We were able to distinguish patients with UC from those with colon-only CD based on increased mucosal expression of genes that mediate type 2 and type 17 immune responses. Increased expression at diagnosis of genes that mediate a type 2 immune response is associated with response to therapy and remission in pediatric patients with UC.

Numerical analysis of the thermal and flow behavior of CuO-water nanofluid under turbulent regions in a shell and tube heat exchanger was conducted using ANSYS Fluent. Twenty-nine (29) nm diameter CuO nanoparticles, and water as base fluid were used in the study. The nanofluid was simulated at different particle loading (0.1 to 1%vol), and under three sets of Reynolds number (ranging from 17,000 to 71,000), to study the effects on heat transfer coefficient, pressure drop, and nanofluid thermal and hydrodynamic behavior. Increasing the particle loading and Reynolds number was found to enhance both the heat transfer rate and pressure drop. A maximum of 48% enhancement in the heat transfer was observed at the highest particle loading, but with the consequence of doubled pressure drop. Performance indices greater than 1 were attained for particle loading below 0.25%vol, regardless of the Reynolds number. The conditions that produced the highest index were at the lowest particle loading and lowest Reynolds number. No significant difference in the flow behavior between water and CuO-water nanofluid was observed. However, the thermal profiles for 0.1%vol CuO-water nanofluid highlighted the enhancements in heat transfer along the shell and tube heat exchanger.

Abstract IL-33 is upregulated in ulcerative colitis and has a protective role in chemically-induced acute murine colitis. We aimed to determine whether IL-33 influences Il10 −/− chronic colitis and its cellular source in health and during colitis. Il10 −/− Il33 −/− and Il10 −/− Il33 +/+ littermates developed colitis of similar severity. Colon Il33 was induced in WT and Il10 −/− mice exposed to DSS, but not in unchallenged Il10 −/− mice with colitis. Il33-citrine reporter mice showed that Il33-citrine colocalized with α-smooth muscle actin+ myofibroblasts and vimentin+ fibroblasts in WT mice. Citrine+CD74+CD90hi inflammatory fibroblasts were increased with DSS treatment. IL-1β induced Il33 expression in colon myofibroblasts, but colon Il33 expression did not differ between DSS-treated WT and Il1r1 −/− mice. In conclusion, deficiency of IL-33 does not alter the severity of chronic colitis in Il10 −/− mice. Induction of Il33 upon DSS exposure in WT and Il10 −/− mice, but not in unchallenged Il10 −/− mice, suggests epithelial injury induces colon IL-33. Fibroblasts are the primary colonic source of IL-33 and IL-33-expressing CD90hiCD74+ fibroblasts are increased during DSS-induced colitis. IL-1β induces Il33 in colon myofibroblasts in vitro, but signaling through the IL-1R1 is not necessary for induction of IL-33 in DSS-induced colitis.