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Effect of frequency and length of time of electrical pulses on cow milk treated with high-pulsed electric field and ultraviolet (UV) technology
No full textMilk is a nutrient-rich animal product but is prone to contamination by spoilage and pathogenic microbes due to its high protein content. Non-thermal sterilization using UV and high-pulsed electric fields (HPEF) offers a solution. This compact system includes a processing chamber with a stirrer, UV lamp, PEF electrodes, and control devices for efficient sterilization. The system operates without damaging the quality of the beverage, making it superior to conventional methods. This study aims to determine the appropriate frequency and length of time to be applied to cow’s milk. The research was conducted using a Factorial Randomized Block Design (FRBD) with two factors: frequency (10, 20, and 30 Hz) and duration (10, 15, and 20 minutes). The parameters tested in this study included total dissolved solids, solid non-fat, protein, fat, and total plate count (TPC). The results showed that increasing the frequency and duration effectively reduced the levels of total dissolved solids, TPC, and fat, while increasing protein and solid non-fat contents. Based on the analysis, HPEV-UV Milk contains TDS 7.30% - 7.80%, SNF 7.59% - 7.79%, protein 2.79% to 2.84%, fat 1.39% - 1.70%, and TPC 5.10 to 18.23 × 10⁶ CFU/g
Characterization of Dar Bouaazza’s Mine Tailings Using Xrf, Acid-Base Accounting, And Leaching Tests (Taza Province, Morocco)
No full textThe present work evaluates the potential of Dar Bouaazza's mine tailings, located in Taza province Morocco, to generate acid mine drainage. In this regard, four samples (R2, R3, R6 and R7) were collected from the wastes left from previous mining operations. X-Ray Fluorescence (XRF) analyses revealed a predominance of lead (Pb) concentrations reaching 44.5% and Sulfur (S) contents ranging from 2.6% to 12.9%, suggesting the presence of sulfide minerals prone to oxidation. Static Acid-Base Accounting (ABA) tests showed high Acid-generation Potential (AP) values between 82 and 397 KgCaCCb/ton and low Neutralization Potential (NP). This lead to strong negative Net Neutralization Potential (NNP), classifying these tailings as acid generating, that causes a risk of Acid Mine Drainage (AMD). Furthermore, kinetic leaching tests using US RPA TCLP and French standards confirmed the presence of high lead concentrations, especially under acidic conditions, exceeding environmental standards. However, copper and zinc concentrations were lower, while arsenic showed increased solubility in neutral leaching conditions. Iron levels, on the other hand, remained within acceptable limits. The integration of all these tests showed significant environmental risks linked with Bouaazza's mine tailings
Spring rains, extremes, and risks in northern Morocco: Fluctuations and trends (March 2024)
No full textThe objective of this study is to examine the climatic conditions during this short rainy period and analyze the various atmospheric conditions responsible for the extreme precipitation recorded. It also examines the risks they posed in terms of flooding and property damage. The focus is on total monthly precipitation and daily maximums, with March holding the record values. Finally, the positive and negative impacts of this exceptional period on water resource mobilization and the agricultural sector will be examined. The methodology adopted in this study aims to characterize extreme spring rainfall in the two cities of the Tangier region (Tangier and Chefchaouen) during the year 2024, particularly in March. The proposed approaches are divided into two categories: the dynamic approach to explain synoptic situations, weather types, and climatic conditions; and the analytical approach to analyze rainfall series for the year 2024 (March). In addition, the Gumbel method enabled us to determine the return periods of precipitation (1976-2024)
Hydrological Assessment of Climate Change Impacts on the Upper Tassaoute Watershed, Morocco
No full textThe Tassaoute watershed, a significant tributary of the Oum Er-Rbia basin in central Morocco, is experiencing increasing water stress due to climate variability and declining precipitation trends. This study aims to assess the impacts of recent climatic changes on water resources in the watershed using the HBV (Hydrologiska Byrâns Vattenbalansavdelning) conceptual hydrological model. Monthly meteorological and hydrological data were collected and used to calibrate and validate the HBV model, enabling simulation of runoff and the evaluation of the watershed's hydrological response to observed climate variability. The results highlight a noticeable reduction in streamflow and changes in seasonal water availability, which are closely linked to variations in rainfall and temperature patterns over recent decades. These findings underline the growing vulnerability of the Tassaoute watershed to climatic fluctuations and provide a scientific basis for improving water resource management in the region
Invasive Alien Species: Their Impact on Degraded Mangrove Forest Ecosystems
No full textInvasive Alien Species (IAS) plants in mangrove forests are plants that can reproduce rapidly and dominate mangrove forest areas due to their adaptability. This study aims to identify IAS species and analyze the impacts caused by their invasion in the mangrove forest area of the Air Telang Protected Forest (ATPF). The method used in this study is a survey method with sampling through a purposive sampling method. IAS plant samples were determined through a survey in the ATPF area, from land to the coast. This study succeeded in identifying three species of IAS plants, namely Nypa fruticans, Acrostichum aureum, and Derris trifoliata. These three plants are mainly found in degraded areas in the form of open shrub areas and secondary forests, both in land and coastal areas. The impacts caused by the presence of IAS in the ATPF area include reduce biodiversity, alter habitat structure, disrupt food chains, diminish fisheries productivity, reduced other ecosystem services and increase fire risk
Connections between the cycle-to-cycle light curve and O−C variations of the Blazhko RR Lyrae stars
No full textContext. Recent studies have shown that the irregular O−C variations observed in many non-Blazhko RR Lyrae stars may result from random, cycle-to-cycle (C2C) variations in their light curves. However, centuries-long data series reveal that the O−C diagrams of Blazhko stars exhibit particularly large-amplitude, irregular variations.
Aims. In this letter, we extend the previous investigation of non-Blazhko stars to Kepler Blazhko stars to explore the role of C2C variations in the O−C diagrams.
Methods. We derived the O−C diagrams from Kepler space telescope light curves using a precise template-fitting method. Based on their Fourier analyses, we also constructed residual O−C diagrams that were pre-whitened for frequencies associated with the Blazhko effect. We then fitted the same statistical models to both types of O−Cs that we had previously applied to non-Blazhko stars.
Results. The optimal statistical model includes the C2C variation for 74% of the O−C curves in our Blazhko sample, and the parameter describing the strength of the C2C variation is significantly larger than that obtained for non-Blazhko stars. This may explain the strong irregular O−C variations previously observed in Blazhko stars. Furthermore, we found a strong positive correlation between the C2C variation strength and the amplitude of the frequency-modulation component of the Blazhko effect, indicating a connection between the two phenomena
Discovery of a galaxy associated with the HI cloud FAST J0139+4328
No full textThe search for “dark galaxies”, a key prediction of the lambda cold dark matter, has yielded few viable candidates. Recently, FAST J0139+4328 was reported as the first isolated dark galaxy in the nearby universe, based on a neutral hydrogen (HI) detection and a non-detection in the Pan-STARRS1 survey. To verify the nature of this candidate, we obtained deep optical imaging, using the 1.4 m Milanković and 0.6 m Nedeljković telescopes, and spectroscopic follow-up of the field. We report the unambiguous discovery of a low-surface-brightness (LSB) optical counterpart at the location of the HI cloud. Furthermore, the detection of Hα emission via the 6 m Big Telescope Alt-Azimuthal (BTA) confirms that the stellar system lies at a redshift consistent with the HI source, establishing their physical association. Through detailed photometry and employing color-dependent mass-to-light scaling relations, we derive a total stellar mass of M★ = (7.2 ± 3.7)×106 M⊙, about an order of magnitude higher than the previously estimated upper limit. Using the literature HI mass, this implies a gas-to-stellar mass ratio of MHI/M★ = 11.5 ± 6.4. Our findings demonstrate that FAST J0139+4328 is not a dark galaxy but an extremely gas-rich LSB dwarf galaxy, whose stellar component was simply below the detection limit of the Pan-STARRS1 survey. This reclassification resolves the status of this prominent dark galaxy candidate and underscores the necessity of deep optical follow-up to classify faint HI-selected systems
Éditorial : Cultures - Actualités de la SFO : Un renouvellement dans la continuité et dans l’action pour la Société Française d’Optique !
No full textAfforestation of tropical watersheds to minimize flood risk in the parish of Valle Hermoso, Ecuador
No full textThis paper presents the implementation and outcomes of a community-based afforestation project in the Valle Hermoso parish (Santo Domingo de los Tsáchilas, Ecuador), aimed at mitigating flood risk. From 2021 to 2024, the University of the Armed Forces (ESPE) facilitated the distribution of over 2,500 Guadua angustifolia Kunth (caña guadua) plants to 250 farms across nine sub-districts, engaging 230 volunteers from the university and local community. The study maps historical flood zones and the newly forested areas surrounding the Blanco and Cristal rivers. After 3.5 years, a 55% survival rate indicates successful plant establishment and a positive project outcome. The afforestation has demonstrably increased dry-season stream flow, reduced flooding, and stabilized riverbanks, thereby minimizing landslides. These results position the project as an effective and scalable model for the broader Tsáchila province, though scalability may encounter financial, logistical, and managerial hurdles. The primary challenge remains ensuring long-term sustainability, which is heavily dependent on continued community participation and support, factors vulnerable to external economic and social pressures
GIS-based mapping and profiling of forest cover and freshwater resources for sustainable and climate-resilient resource management in the island barangays of Surigao City, Philippines
No full textThe increasing environmental challenges in the island barangays of Surigao City, including deforestation, freshwater scarcity, and climate change impacts, necessitate a systematic approach to resource management. This study utilized Geographic Information Systems (GIS) to map and analyze the forest cover and freshwater resources of Nonoc, Hikdop, and Bayagnan Islands. Data was collected through satellite imagery, field surveys, and Digital Elevation Models (DEM), and Normalized Difference Vegetation Index (NDVI) to assess vegetation distribution, water sources, topography, and terrain characteristics. Findings reveal that most barangays exhibit tertiary growth forests, with freshwater primarily sourced from natural springs and deep wells. GIS-based analysis of elevation, slope, and aspect provided critical insights into potential environmental risks such as flooding, erosion, and land degradation. The study highlights the need for integrated GIS monitoring systems, sustainable water resource management, reforestation initiatives, and disaster risk mitigation strategies. These findings serve as a valuable tool for policymakers, conservationists, and local communities in fostering evidence-based environmental planning and sustainable development