Terms Of Potential Research Articles

Abstract P4-07-05: Real world data of adjuvant endocrine therapy for breast cancer in very young women. A Chilean 20-year experience

Abstract BACKGROUND: Breast cancer (BC) is the most common cancer diagnosed in premenopausal women with an increasing incidence for age 35 or less. Although proportionally less frequent, hormone receptor (HR)–positive BC still remains the main subtype for this group, but given tumor characteristics and suboptimal adjuvant endocrine therapy (ET), present inferior long-term outcomes when compared to HR-positive BC in older women. Both Tamoxifen and Exemestane Trial (TEXT) and Suppression of Ovarian Function Trial (SOFT) have helped to optimize ET strategies for premenopausal women, identifying which patients benefit from ovarian function suppression (OFS). In Chile, we have scarce data on very young BC patients and limited access to proper OFS treatment specially in our public health system. Thus we aim to characterize a cohort of very young women regarding treatment strategies and survival, plus as an exploratory analysis evaluate Regan Score in our cohort. METHODS We conducted a retrospective population-cohort study involving women under 36 years of age, with early HR-positive/human epidermal growth factor receptor 2 (HER2)–negative BC, treated both at a community hospital and at an academic private hospital between 2001 and 2021. We did a descriptive analysis including stage distribution and treatment strategies (chemotherapy (CT), ET of choice and OFS use). We evaluated prognosis for the entire population. Survival analysis was carried out using the Kaplan-Meier method. RESULTS A total of 143 patients were included. Median age at diagnosis was 33 (19 - 36); 15.4% percent of patients were diagnosed in stage I, 51.4% stage II and 30.1% stage III. Eighty six percent received CT, 35.0% neoadjuvant. Ninety three percent received endocrine adjuvant treatment: 81.2% TAM alone, 6.8% TAM/OFS and 10.5% IA/OFS. Regarding OFS strategies only 38.5% received gonadotropin-releasing hormone (GnRH) agonists while the rest were oophorectomized. Regan median composite score was 2.77 (2.61 - 2.93) for the entire cohort. Rising to 2.95 (2.79 - 3.11) for patients treated with CT plus ET compared to 1.91 (1.55 - 2.27) for those treated with ET exclusively (p=0.0001). Patients that received TAM alone had a median Regan Score of 2.72 (0.77-4) compared to 3.14 (2.07-4.0) for patients that had OFS added (p=0.04). With a median follow-up of 59 months, 5-year Disease Free Survival (DFS), Distant DFS and Overall Survival (OS) for the entire cohort were 63.5%, 66.9% and 88.7%, respectively. CONCLUSION. To our knowledge this is one of the largest cohorts considering very young women BC in Latinamerica. We confirm their elevated overall risk with markedly higher Regan scores compared to SOFT and TEXT populations for both CT and ET exclusively treated patients. Due to access difficulties very few patients received OFS and when used, surgical oophorectomy was the main strategy of choice, with all the potential long term consequences it conveys. Thus OFS use was restricted to very high risk women, meaning that a large group of only TAM users were undertreated according to nowadays standards. This could explain the elevated recurrence risk observed in our population when compared to other under 35 years of age cohorts. Table 1. Cohort characteristics Table 2. Regan risk score Citation Format: Ana Heredia, Benjamin Walbaum, Francisco Acevedo, Cesar Sánchez. Real world data of adjuvant endocrine therapy for breast cancer in very young women. A Chilean 20-year experience [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-07-05.

Estimates on the eigenvalues of complex nonlocal Sturm-Liouville problems

The present paper deals with the eigenvalues of complex nonlocal Sturm-Liouville boundary value problems. The bounds of the real and imaginary parts of eigenvalues for the nonlocal Sturm-Liouville differential equation involving complex nonlocal potential terms associated with nonlocal boundary conditions are obtained in terms of the integrable conditions of coefficients and the real part of the eigenvalues.

An algebraic approach for the Dunkl–Killingbeck problem from the bi-confluent Heun equation

In this paper, we study the Dunkl–Killingbeck problem in two dimensions. We apply the Lie algebraic approach within the framework of quasi-exact solvability to the radial part of the Dunkl–Killingbeck problem to find the general exact expressions for the energies and corresponding wave functions. The allowed values of the potential parameters are the representation space of sl(2) Lie algebra. In addition, we discuss that the effective potential of the Dunkl–Killingbeck is the same as the obtained from the bi-confluent Heun equation by a suitable variable transformation. Following earlier results, we follow the explicit solutions of this differential equation expressed as a series expansion of Hermite functions and obtain the expansion coefficients from a three-term recurrence relation. In the sequel, we present that this construction leads to the known quasi-exactly solvable (QES) form of the Dunkl–Killingbeck problem. Therefore, we find that the expressions for the energy eigenvalues and wave functions of the corresponding potential term are in agreement with those from the QES formalism. Then, we derive the ladder operators for the Dunkl–Killingbeck problem within the algebraic approach. It seems that this method is the Dunkl–Killingbeck rotation problem solved by operators of the su[Formula: see text] Lie algebra in a specific way.

Digital services of regional centers for scientific and technical information in China

The article aims to study the current level of digital services of the regional subsystem of the National System of Scientific and Technical Information of the People's Republic of China and to determine its optimization directions. A content analysis of 28 provincial institutes of scientific and technical information’s official sites was carried out; the most powerful of them were identified in terms of resource and service potential, the level of organization of corporate cooperation based on consolidated digital platforms of multifunctional user service. It is proved that the level of efficiency of digital services of regional scientific and technical information systems directly depends on the level of the province’s economic development and the ability of its government to finance and technologically equip information industry centers activities, and to establish sustainable interaction of all subjects of the information market. Summarizing the results of the content analysis made it possible to identify reserves for improving the service capabilities of the Chinese information industry’s regional clusters, to design vectors for diversifying consulting, expert-analytical, cognitive services of provincial institutes of scientific and technical information, the development of integrated innovation-oriented intelligent service platforms operating based on artificial intelligence technologies.

Global multiplicity for parametric anisotropic Neumann (p,q)-equations

We consider a Neumann boundary value problem driven by the anisotropic $(p,q)$-Laplacian plus a parametric potential term. The reaction is ``superlinear". We prove a global (with respect to the parameter) multiplicity result for positive solutions. Also, we show the existence of a minimal positive solution and finally, we produce a nodal solution.

The Effect of On-Site Potentials on Supratransmission in One-Dimensional Hamiltonian Lattices.

We investigated a class of one-dimensional (1D) Hamiltonian N-particle lattices whose binary interactions are quadratic and/or quartic in the potential. We also included on-site potential terms, frequently considered in connection with localization phenomena, in this class. Applying a sinusoidal perturbation at one end of the lattice and an absorbing boundary on the other, we studied the phenomenon of supratransmission and its dependence on two ranges of interactions, 0<α<∞ and 0<β<∞, as the effect of the on-site potential terms of the Hamiltonian varied. In previous works, we studied the critical amplitude As(α,Ω) at which supratransmission occurs, for one range parameter α, and showed that there was a sharp threshold above which energy was transmitted in the form of large-amplitude nonlinear modes, as long as the driving frequency Ω lay in the forbidden band-gap of the system. In the absence of on-site potentials, it is known that As(α,Ω) increases monotonically the longer the range of interactions is (i.e., as α⟶0). However, when on-site potential terms are taken into account, As(α,Ω) reaches a maximum at a low value of α that depends on Ω, below which supratransmission thresholds decrease sharply to lower values. In this work, we studied this phenomenon further, as the contribution of the on-site potential terms varied, and we explored in detail their effect on the supratransmission thresholds.

Current Status and Development Direction of Low-Carbon Exploitation Technology for Heavy Oil

With the strategic goal of “carbon peaking and carbon neutral” in China, new requirements are also put forward for the thermal recovery of heavy oil. In view of the problems of excessive greenhouse gas emission, low steam utilization rate, poor economic efficiency, and limited reservoir application of steam stimulation replacement technology in China, the emerging technologies of medium- and low-temperature thermal fluid, solvent-assisted high-temperature steam injection, solvent-based medium- and low-temperature waterless recovery and in situ electric heating-assisted recovery are discussed in terms of technical principles, technical parameters, experimental/field effects, and technical and economic potential. The technical principles, technical parameters, experimental/field results, and techno-economic potential of low-carbon heavy oil recovery technologies are summarized and future development directions and trends are anticipated. The study’s findings indicate that some of the technologies that have been tested in the field, such as HWVP, EMVAPEX, AH-VAPEX, LASER, and ESEIEH, can be developed by relying on the original well groups for production and can reduce greenhouse gas emissions, such as CO2, by about 80% and improve crude oil recovery by 5% to 10%, while the technologies concerned have outstanding effects on increasing oil production rate and lowering upfront capital investment. Some of the technologies that have been tested significantly increase oil production rate, lower initial capital expenditure, and enable solvent recycling, among other things. Among them, COBEEOR and N-SOLV technologies can also lower the amount of asphaltene in the output crude oil, enhance the API of the recovered crude oil, and provide strong economic advantages. CSP, CHSI, and hot water solvent injection were tested in indoor two-dimensional and three-dimensional experiments to validate their feasibility, while CO2, propane, and butane solvents were initially screened and some of the technologies’ mechanisms were revealed to lay the groundwork for pilot projects. The executive summary of the research findings will serve as a guide for future low-carbon extraction technology research and development in China.

Van der Waals Dispersion Potential between Excited Chiral Molecules via the Coupling of Induced Dipoles

The retarded van der Waals dispersion potential between two excited chiral molecules was calculated using an approach, in which electric and magnetic dipole moments are induced in each particle by fluctuations in the vacuum electromagnetic field. An expectation value of the coupling of the moments at different centres to the dipolar interaction tensors was taken over excited matter states and the ground state radiation field, the former yielding excited molecular polarisabilities and susceptibilities, and the latter field–field spatial correlation functions. The dispersion potential term proportional to the mixed dipolar polarisability is discriminatory, dependent upon molecular handedness, and contains additional terms due to transitions that de-excite each species as well as the usual u-integral term over imaginary frequency, which applies to both upward and downward transitions. Excited state dispersion potentials of a comparable order of magnitude involving paramagnetic and diamagnetic couplings were also computed. Pros and cons of the method adopted are compared to other commonly used approaches.

Semantic Segmentation of Remote Sensing Imagery Based on Multiscale Deformable CNN and DenseCRF

The semantic segmentation of remote sensing images is a significant research direction in digital image processing. The complex background environment, irregular size and shape of objects, and similar appearance of different categories of remote sensing images have brought great challenges to remote sensing image segmentation tasks. Traditional convolutional-neural-network-based models often ignore spatial information in the feature extraction stage and pay less attention to global context information. However, spatial context information is important in complex remote sensing images, which means that the segmentation effect of traditional models needs to be improved. In addition, neural networks with a superior segmentation performance often suffer from the problem of high computational resource consumption. To address the above issues, this paper proposes a combination model of a modified multiscale deformable convolutional neural network (mmsDCNN) and dense conditional random field (DenseCRF). Firstly, we designed a lightweight multiscale deformable convolutional network (mmsDCNN) with a large receptive field to generate a preliminary prediction probability map at each pixel. The output of the mmsDCNN model is a coarse segmentation result map, which has the same size as the input image. In addition, the preliminary segmentation result map contains rich multiscale features. Then, the multi-level DenseCRF model based on the superpixel level and the pixel level is proposed, which can make full use of the context information of the image at different levels and further optimize the rough segmentation result of mmsDCNN. To be specific, we converted the pixel-level preliminary probability map into a superpixel-level predicted probability map according to the simple linear iterative clustering (SILC) algorithm and defined the potential function of the DenseCRF model based on this. Furthermore, we added the pixel-level potential function constraint term to the superpixel-based Gaussian potential function to obtain a combined Gaussian potential function, which enabled our model to consider the features of various scales and prevent poor superpixel segmentation results from affecting the final result. To restore the contour of the object more clearly, we utilized the Sketch token edge detection algorithm to extract the edge contour features of the image and fused them into the potential function of the DenseCRF model. Finally, extensive experiments on the Potsdam and Vaihingen datasets demonstrated that the proposed model exhibited significant advantages compared to the current state-of-the-art models.

In vitro genotoxicity potential investigation of 7 oxy-PAHs.

Air pollutants include many compounds among them oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs). As they are suspected to generate DNA damage and mutagenicity, an understanding of their mode of action could highlight a carcinogenic potential risk in exposed population. In this article, a prospective study on seven oxy-PAHs selected in terms of occurrence in the environment was conducted on mutagenicity, genotoxicity, and cytotoxicity potentials using in vitro assays including Ames test on five strains, kinetic analysis of cytotoxicity and apoptosis, phosphorylation of histone H2AX, and p53 induction assays on human lung cell line BEAS-2B. Ames test demonstrated that mutagenicity pattern depended on the oxy-PAH tested. Except for BAQ, all oxy-PAHs tested gave mutagenic effect, in the absence and/or in the presence of metabolic activation (S9 fraction). At 24 h of exposure, the majority of oxy-PAHs induced γ-H2AX in BEAS-2B cells and/or phosphorylation of p53 at serine 15 and cell death at highest tested concentrations. Although 9,10-AQ and B[b]FO were mutagenic in bacteria, they failed to induce any of the other genotoxicity biomarkers. In comparison with the benzo[a]pyrene, all oxy-PAHs were less potent in terms of genotoxic potential at the same concentration. These results highlighted the genotoxic and mutagenic potential of these oxy-PAHs and provide preliminary information concerning their possible mechanism of action for toxicity, contributing to a better evaluation of the real associated health risks for human and environment.

Co supported on N and S dual-doped reduced graphene oxide as highly active oxygen-reduction catalyst for direct ethanol fuel cells

Oxygen reduction reaction (ORR) is one of the key features for the efficient functioning of several energy conversion devices such as fuel cells, appearing the necessity of development of new low-cost catalyst materials. Heteroatom-doped carbon materials have attracted attention in this field due to its physicochemical and electronic properties. In this work, a nitrogen and sulfur doped material with anchored Co3O4 nanoparticles (Co/SN-rGO) is proposed as cathode catalyst for direct ethanol fuel cells (DEFCs) and results are compared with different doped graphene nanomaterials (GMs). The effect of the heteroatoms and cobalt oxide nanoparticles in the final efficiency was studied. Synthesized materials were characterized and the activity of Co/SN-rGO and GMs for the ORR was studied. Co/SN-rGO presents high ORR performance in terms of onset potential (Eonset), 0.86 V (vs RHE) and half-wave potential (E1/2) 0.72 V (vs RHE). Tafel analysis shows 60 mV dec-1 at low overpotential for potential dependent ORR mechanism. Besides, when Co/SN-rGO performance is evaluated in a DEFC using a fuel cell test station, main results indicate higher catalytic activity, stability, and ethanol tolerance of Co/SN-rGO in comparison to a carbon-supported Pt catalyst.

Levels of Physical Activity before and after California’s COVID-19 Shutdown among a Population-Based Sample of Mothers from Low-income Households

We examined changes in levels of physical activity (PA) before versus after California’s COVID-19 shutdown among mothers from low-income households across California. By comparing the same time periods in Federal Fiscal Year (FFY) 2020 to those in FFYs 2018, 2019, and 2021, we were able to assess whether the changes observed in FFY 2020 were different from those in pre-pandemic years, and the potential longer term impact of COVID-19 on PA. Households with incomes ≤185% of the federal poverty level were randomly selected in FFYs 2018-2021. Within each FFY, cross-sectional interviews were conducted by telephone in English or Spanish. Two outcome variables were examined: minutes of PA per week and whether guidelines of ≥150 minutes of weekly PA were met. Analyses examined these outcomes across and within FFYs by COVID-19 shutdown time periods controlling for race/ethnicity, age, education, and multiple comparisons. Among our analytic sample of 13,267 mothers, 65.2% were Latina, 16.6% were white, and 12.7% were African American. Levels of PA among mothers increased following California’s COVID-19 shutdown. Similar findings were observed within each of the four FFYs for both PA outcomes. We attribute our findings to a seasonal effect, with levels of PA increasing during warmer, post-COVID-19 shutdown months (May through September). We also suggest that the low-income status of our study population may explain why our findings contradict those reported in previous studies. The initial and repeated closure of gyms and fitness centers may have been less disruptive to our samples of mothers, who reported walking at rates higher than the general US population. Mothers may have also been more likely to come from households that received enhanced unemployment or other types of COVID-19 benefits, offering the means and time to continue their pattern of seasonal increases in PA in FFYs 2020 and into 2021.

Environmental profiling microalgae-based eicosapentaenoic acid production along the technical advancement via life cycle assessment

Microalgae have attracted attention from various fields due to their potential ability to accumulate diverse value-added products, including polyunsaturated fatty acids (PUFAs). Many approaches have been used to enhance the productivity of microalgae-based PUFAs, such as eicosapentaenoic acid (EPA), but in many cases, these have only focused on economic competitiveness. However, it is imperative to simultaneously quantify and optimize the associated environmental impact at an early stage to guide future developments and sustainable scale-up. This study conducted Life Cycle Assessments (LCA) along the technical advancements of laboratory-scale EPA production by Phaeodactylum tricornutum. Results indicated that technical advancements enhanced the environmental performance associated with EPA production. Among these, metabolic engineering led to the most significant reductions (93.48% and 93.45%) in terms of global warming potential and cumulative energy demand compared with the wild-type scenario due to elevated microalgal growth and EPA yield. Electricity consumption remained the dominant contributor to the associated environmental impact, followed by extraction solvents, especially chloroform. In terms of processes, cultivation of the microalgae and harvesting of the biomass accounted for the majority of the impact attributed to the long cultivation period and the energy-intensive processes such as freeze drying. As guided by the sensitivity analysis, future directions should focus on further increasing EPA productivity, adopting alternative cultivation approaches with less energy input, and recovering EPA via environmentally friendly methods.

MERCEDES-BENZ FRAMES IN $$\mathbb {R}^d$$ AS A DIRECT SUM OF A PAIR OF ORTHOGONAL TIGHT FRAMES

The well-known Mercedes-Benz frames in $$\mathbb {R}^d$$ are known to exist and they have been constructed too. They are presented here as an external direct sum of a pair of orthogonal frames. A necessary and sufficient condition for a unit norm tight frame to be a Mercedes-Benz frame in $$\mathbb {R}^d$$ is provided in terms of a vector from the null space of its synthesis operator. Also, a necessary and sufficient condition for a unit norm system of vectors to be a Mercedes-Benz frame is provided in terms of the frame potential and a vector from the null space of the synthesis operator.

Comparative Life Cycle Assessment of Two Different Packaging Systems for Extra-Virgin Olive Oil: Glass Bottle vs. 100% Recycled Polyethylene Terephthalate (PET) Bottle

Using the Life Cycle Assessment methodology, this study assesses the environmental sustainability of two packaging alternatives for extra virgin olive oil: the glass bottle and the PET bottle produced with 100% of recycled PET granulate. Six scenarios were compared varying on the type of packaging system and the distribution phase (in terms of distribution country and logistics). The life cycle impacts of the scenarios were estimated with the ReCiPe 2018 H evaluation method, using both the midpoint and endpoint approaches. The findings highlighted the higher environmental sustainability of the recycled PET system compared to the glass system for all the impact categories considered, but especially in terms of the global warming potential, particulate formation, terrestrial acidification, and fossil fuel scarcity for which life cycle impacts of the R-PET were lower than 40% compared to those of the glass system. In terms of global warming, the glass system was responsible for 790–1137 kg CO2 eq. (in function of the destination country considered); while the R-PET system, in the same conditions, showed impacts of 459–634 kg CO2 eq. This is mainly due to the high weight of the glass bottle that affected the impacts of both the production and distribution phases. The mode of transport affected the impacts of the distribution phases highlighting how ship transport was more sustainable than truck transport, even when considering greater distribution distances. The LCA results can help consumers make more informed choices with a view to sustainability, as well as disprove the prejudices that consumers often have towards glass bottle packaging alternatives.

Grain Yield and Yield Related Traits of Bread Wheat as Influenced by N and Seeding Rates and Their Interaction Effects in 2020 under Irrigation at Western and North of Oromia, Ethiopia

Wheat is among the cultivated and important crops in Ethiopia because of its high value as a stable food that is mostly grown under rain-fed conditions. Even though the country has the potential to produce a sufficient amount of wheat grain under rain-fed and by using irrigation, the country still depends on importing wheat grain every year. Soil fertility depletion, inappropriate agronomic practices, erratic rainfall, and drought are among the constraints to the low yield of wheat crops in the country. In view of this, the field experiment was conducted during the off-season of 2020 in five districts, namely, Horo, Jimma Geneti, Jimma Arjo, Wayu Tuka, and Degem districts that are selected as representatives in terms of agricultural production and irrigation potential. The treatments consisted of five N fertilizer levels (0, 23, 46, 69, and 92 kg·ha−1) and three seeding rates (125, 150, and 175 kg·ha−1) of bread wheat, which constituted a total of 15 treatments. The experiment was laid out in a randomized complete block design with a factorial arrangement in three replications. The plot size was 3 m × 5 m. From the study, we observed that the grain yield and yield components of wheat were improved by optimizing nitrogen application and plant population. Maximum grain yield of 6.8, 8.9, 4.1, 4.8, and 2.5 t·ha−1 was recorded in response to the use of 92/125, 23/150, 23/150 and 175, 69/150, and 69/175 kg·ha−1 N/seed rate of wheat under irrigation condition in Horo, Jimma Geneti, Jimma Arjo, Wayu Tuka, and Degem districts, respectively. On the contrary, the lowest yield was observed from the unfertilized plot that was planted at 125 kg·ha−1 seed rate in all districts, except in Jimma Geneti, which was observed at 0/150 kg·ha−1 N/seed rate. The differences in yield between districts are mainly attributed to the variability in their soil-plant nutrient contents. Thus, N fertilizer and seed rates at 23/150, 69/150, 46/50, and 92/125 kg·ha−1 in Jimma Arjo and Jimma Geneti, Wayu Tuka, Degem, and Horo districts, respectively, gave maximum yield and net benefit with acceptable marginal rate of return, and it is economically feasible and the best rate to use by the end-users in bread wheat production under irrigation condition in the study area and agro-ecologies that are similar to the study area.

Conservation Paleobiology and Taphonomy: Differential Preservation and Time-Averaging of Echinoids and Mollusks

Fossils from surficial death assemblages and shallow cores are an important archive used in the field of conservation paleobiology. Understanding the taphonomic filters and time-averaging that affect modern biomineralized taxa is crucial for using their fossil record as a source of geohistorical data. Through comparative analysis of the live-dead patterns of echinoids and mollusks, we aim to assess multiple hypotheses regarding differences between the two taxa in terms of preservation potential and fossil record resolution. In this pilot study, six sediment samples (five surface [0-10cm] and one subsurface [30-40cm]) were collected in a shallow, subtidal habitat off the coast of Cedar Key, Florida. These samples were sieved for mollusks and echinoids. Specimens were segregated by taxa and classified into live, whole dead, and fragments. Results were consistent among surface samples, which showed that, by weight, an average of 8% of all mollusk specimens and 55% of all echinoid specimens were live collected. Fragmentation rate by weight was notable higher for echinoids than for mollusks: 77% for mollusks and &gt;99% for echinoids. The subsurface sample lacked complete echinoid tests, but complete mollusks shells, mollusk fragments and echinoid fragments remained common. These results support the hypothesis that echinoid tests degrade more quickly than mollusk shells, making them less likely to be preserved as part of time-averaged assemblages formed under low net-accumulation rates. Echinoid fragments do not seem to follow this pattern, and instead seem to preserve similarly to mollusks. The results suggest that geohistorical records provided by echinoids and mollusks may be fundamentally distinct from one another in terms of temporal resolution and completeness of the fossil record.

A mechanistic mathematical model for photo fermentative hydrogen and polyhydroxybutyrate production.

An original mathematical model describing the photo fermentation process is proposed. The model represents the first attempt to describe the photo fermentative hydrogen production and polyhydroxybutyrate accumulation, simultaneously. The mathematical model is derived from mass balance principles and consists of a system of ordinary differential equations describing the biomass growth, the nitrogen and the substrate degradation, the hydrogen and other catabolites production, and the polyhydroxybutyrate accumulation in photo fermentation systems. Moreover, the model takes into account important inhibiting phenomena, such as the self-shading and the substrate inhibition, which can occur during the evolution of the process. The calibration was performed using a real experimental data set and it was supported by the results of a sensitivity analysis study. The results showed that the most sensitive parameters for both hydrogen and PHB production were the hydrogen yield on substrate, the catabolites yield on substrate, and the biomass yield. Successively, a different experimental data set was used to validate the model. Performance indicators showed that the model could efficiently be used to simulate the photo fermentative hydrogen and polyhydroxybutyrate production by Rhodopseudomonas palustris. For instance, the index of agreement of 0.95 was observed for the validated hydrogen production trend. Moreover, the model well predicted the maximum PHB accumulation in bacterial cells. Indeed, the predicted and observed accumulated PHB were 4.5 and 4.8%, respectively. Further numerical simulations demonstrated the model consistency in describing process inhibiting phenomena. Numerical simulations showed that the acetate and nitrogen inhibition phenomena take place when concentrations are higher than 12.44 g L-1 and lower than 4.76 mg L-1, respectively. Finally, the potential long term hydrogen production from accumulated polyhydroxybutyrate in bacterial cells was studied via a fast-slow analysis technique.

Normalized Solutions to the Kirchhoff Equation with Potential Term: Mass Super-Critical Case

Normalized Solutions to the Kirchhoff Equation with Potential Term: Mass Super-Critical Case

Screening and characterization of phenolic compounds by LC-ESI-QTOF-MS/MS and their antioxidant potentials in papaya fruit and their by-products activities

Papaya (Carica papaya L.) is one of the most commonly planted and consumed fruits in the world, especially in tropical and subtropical areas. In recent years, due to the diverse range of nutritional value and medicinal properties of bioactive substances possessed in papaya, papaya fruit and their by-products have gained more attention. The present study aimed to characterize the different parts (pulp, peel, and seed) of two varieties of papaya (yellow- and red-fleshed) at different stages of ripeness (unripe and ripe) for their phenolic compounds using liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS). The phenolic content and antioxidant activity were detected through several assays. Yellow-fleshed unripe papaya seed showed the highest total phenolic content (TPC) (4.73 mg GAE/g). Red-fleshed ripe papaya peel exhibited the highest level of total tannin content (TTC) with 1.98 mg CE/g, while red-fleshed unripe peel exhibited the highest total flavonoid content (TFC) with 2.78 ± 0.04 mg QE/g. In terms of antioxidant potential, yellow-fleshed unripe papaya peels had the highest radical scavenging activities for the DPPH, ABTS, and TAC tests. LC-ESI-QTOF-MS/MS experiment successfully tentatively identified 118 phenolic compounds in total, including phenolic acids (35), flavonoids (61), stilbenes (3), lignans (7) and other polyphenols (12) in all papaya samples. Analyses indicate that the three different parts of the papaya fruit are potential sources of phenolic compounds, particularly the peel. The results of this study provide practical data for the potential application of papaya fruit as a functional food ingredient in the food, pharmaceutical and medicinal industries.