bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced groundwater availability through rainwater harvesting and managed aquifer recharge in arid regions
Authors: Abd-Elaty Ismail , Kuriqi Alban , Ahmed Ashraf , Ramadan Elsayed M. 
Published: May 2024

AbstractClimate change in desert areas and semi-arid watersheds may offer a promising solution for the water scarcity problem that Bedouins and local inhabitants face. This study investigated the integrated water resources management in arid and semi-arid regions using rainwater harvesting in combination with the managed aquifer recharge (RWH-MAR) technique. The study also used recharge wells and storage dams to achieve the sustainability of groundwater supplies in the context of climate change and management of the flow to the Gulf of Suez. Therefore, different return periods of 10, 25, 50, and 100 years were considered for the annual flood volume resulting from those watersheds. Moreover, hydrologic modeling was carried out for the El Qaa plain area, South Sinai, Egypt, using the Watershed Modeling System (WMS) and the groundwater modeling of SEAWAT code. Our findings show that for different scenarios of climate change based on return periods of 10, 25, 50, and 100 years, the aquifer potentiality reached 24.3 MCM (million cubic meters) per year, 28.8 MCM, 36.7 MCM, and 49.4 MCM compared to 21.7 MCM at 2014 with storage of groundwater ranges 11.8%, 32.1%, 69%, and 127.4%, respectively. These findings have significant implications for the system of RWH-MAR and groundwater sustainability in El Qaa Plain, South Sinai. The RWH-MAR proved to be an effective approach that can be applied in different water-stressed and arid regions to support freshwater resources for sustainable future development and food security, as well as protect communities from extreme flash flood events.
Experimental study on the pseudo threshold pressure gradient of supported fractures in shale reservoirs
Authors: Gao Jidong , Zhu Weiyao , Li Aishan , He Yuexiang , Zhang Liaoyuan , Kong Debin 
Published: May 2024

AbstractPseudo threshold pressure gradient (PTPG) exists in the propped fractured reservoir, but its nonlinear flow law remains unclear. The effects of the mineral composition of shale and microstructure of fracturing fluid on PTPG were analyzed by X-ray diffraction and liquid nitrogen quick-freezing method. The results demonstrate that a proppant with a large particle size is more likely to form an effective flow channel and reduce liquid flow resistance, thus decreasing PTPG and increasing conductivity. The polymer fracturing fluid with rectangular microstructures significantly increased the PTPG supporting the fractured core. Experimental results show that the PTPG of the resin-coated sand-supported core in the fracturing fluid with a concentration of 1.2% is 245 times higher than that in the fracturing fluid with a concentration of 0.1% when the confining pressure is 5 MPa. Wetting hysteresis and the Jamin effect are responsible for the rise of PTPG in two-phase flow. The equivalent fracture width shows a good power function relationship with the PTPG. Thus, this study further explains the nonlinear flow behavior of reservoirs with fully propped fractures.
Maximizing the capacity and benefit of CO2 storage in depleted oil reservoirs
Authors: Sang Qian , Yin Xia , Pu Jun , Qin Xuejie , Gou Feifei , Fang Wenchao 
Published: May 2024

AbstractSequestering CO2 in depleted oil reservoirs provides one of the most appealing measures to reduce greenhouse gases (GHG) concentration in the atmosphere. The remaining liquids after enhanced oil recovery (EOR) processes, including residual oil and remaining water, lead to the main challenges to this approach. How to effectively evacuate a depleted oil reservoir by recovering not only residual oil but also remaining water is a critical consideration for this type of CO2 sequestration. This paper presents conceptual investigations concerning the methods which effectively evacuate depleted oil reservoirs from both the displacement efficiency and the sweep efficiency points of view. To improve the displacement efficiency, surfactant slug and solvent slug injection was examined using a core scale numerical model. Investigations regarding improving sweep efficiency, such as horizontal well pattern infilling and foam injection, were carried out based on a typical row well pattern. Simulation results showed that surfactant slug which modified the relative permeability and capillary pressure remarkably reduced both residual oil saturation and remaining water saturation. A CO2 slug injected before surfactant slug can help improve the oil recovery. Solvent enriched CO2 slug also remarkably reduced the residual oil saturation to as low as 2%. Horizontal well pattern infilling had great advantage for thick or inclined reservoirs, and foam slug injection greatly improved CO2 storage capacity in thin reservoirs by improving the sweep efficiency. Maximum mobility reduction (MRF) is the most important parameter to maximize the storage capacity and the benefit. The variation of CO2 storage capacity along with CO2 slug size. Larger foam slug size will play a better storage performance. The conceptual simulation investigations confirmed that depleted oil reservoirs can be effectively evacuated for CO2 storage. Depleted oil reservoirs with maximum evacuation are the best candidates for CO2 sequestrations.
Can Urban Air Mobility become reality? Opportunities and challenges of UAM as innovative mode of transport and DLR contribution to ongoing research
Authors: Pak Henry , Asmer Lukas , Kokus Petra , Schuchardt Bianca I. , End Albert , Meller Frank , Schweiger Karolin , Torens Christoph , Barzantny Carolina , Becker Dennis , Ernst Johannes Maria , Jäger Florian , Laudien Tim , Naeem Nabih , Papenfuß Anne , Pertz Jan , Prakasha Prajwal Shiva , Ratei Patrick , Reimer Fabian , Sieb Patrick , Zhu Chen , Abdellaoui Rabeb , Becker Richard-Gregor , Bertram Oliver , Devta Aditya , Gerz Thomas , Jaksche Roman , König Andreas , Lenz Helge , Metz Isabel C. , Naser Fares , Schalk Lukas , Schier-Morgenthal Sebastian , Stolz Maria , Swaid Majed , Volkert Andreas , Wendt Kristin 
Published: May 2024

AbstractUrban Air Mobility (UAM) is a new air transportation system for passengers and cargo in urban environments, enabled by new technologies and integrated into multimodal transportation systems. The vision of UAM comprises the mass use in urban and suburban environments, complementing existing transportation systems and contributing to the decarbonization of the transport sector. Initial attempts to create a market for urban air transportation in the last century failed due to lack of profitability and community acceptance. Technological advances in numerous fields over the past few decades have led to a renewed interest in urban air transportation. UAM is expected to benefit users and to also have a positive impact on the economy by creating new markets and employment opportunities for manufacturing and operation of UAM vehicles and the construction of related ground infrastructure. However, there are also concerns about noise, safety and security, privacy and environmental impacts. Therefore, the UAM system needs to be designed carefully to become safe, affordable, accessible, environmentally friendly, economically viable and thus sustainable. This paper provides an overview of selected key research topics related to UAM and how the German Aerospace Center (DLR) contributed to this research in the project "HorizonUAM - Urban Air Mobility Research at the German Aerospace Center (DLR)". Selected research results on the topics of market potential and public acceptance, vehicle design (including battery degradation, onboard systems, cabin design, cabin simulation), infrastructure, operations (including U-space, safe autonomy, navigation, communication, cost modeling) and overall system modeling are briefly presented.
Efficacy of multivitamin support following bariatric surgery in patients with obesity: a prospective observational study
Authors: Basolo Alessio , Bechi Genzano Susanna , Vitti Jacopo , Salvetti Guido , Gilio Donatella , Ceccarini Giovanni , Scartabelli Giovanna , Lippi Chita , Bellini Rosario , Mancini Rudi , D’Imporzano Simone , Moretto Carlo , Angeli Valentina , Troiani Daniela , Fierabracci Paola , Jaccheri Roberta , Calderone Alba , Poma Anello M. , Chiovato Luca , Saponati Giorgio , Santini Ferruccio 
Published: May 2024

Abstract
Purpose
Bariatric surgery (BS), an effective treatment for severe obesity and its comorbidities, may result in micronutrient and vitamin deficiencies. This monocentric prospective observational study aimed at evaluating the efficacy of a specifically designed vitamin/mineral formula (Bariatrifast, BIOITALIA S.r.l., Italy) for preventing and treating micronutrient deficiencies in patients submitted to BS.

Methods
Twenty patients with severe obesity (mean weight and BMI: 123.5 kg (range 88–174) and 43.3 kg/m2 (range 37–54) respectively) underwent BS (10 vertical sleeve gastrectomy VSG, 10 Roux-en-Y gastric bypass, RYGB). The mean age was 49.9 years (range 27–68). After a presurgical visit (V0), follow-up visits were performed at 1, 3, 6 and 12 months after surgery (V1–V4). Recorded data included weight, height and BMI. A complete blood count, measurement of ferritin, folic acid, vitamin B12, ionized calcium, 25 OH vitamin D, parathyroid hormone (PTH) were obtained. Following BS, patients started the daily oral multivitamin and mineral supplement.

Results
All patients achieved a significant weight loss (mean − 34.7 ± 11.8 kg). No deficiencies of various vitamins/micronutrients were detected during the entire study period. The serum concentrations of vitamin B12, 25-OH Vitamin D and folic acid increased over the follow-up period compared with V0 (mean increase 243 ng/L, 23 µg /L, 8 µg/L, respectively). Compared to RYGB, patients who underwent sleeve gastrectomy showed higher levels of 25-OH vitamin D at V2, V3 and V4 (all p < 0.05), and higher levels of Vitamin B12 and folic acid at V4 (p < 0.05 and p < 0.005, respectively). No adverse events were reported.

Conclusion
Following VSG or RYGB, Bariatrifast administration was associated with normal values of essential micronutrients, and it was well-tolerated without evidence of gastrointestinal side effects.
Clinical Trial Registration ClinicalTrials.gov, identifiers NCT06152965
ATTACK-COSM: attacking the camouflaged object segmentation model through digital world adversarial examples
Authors: Li Qiaoyi , Wang Zhengjie , Zhang Xiaoning , Li Yang 
Published: May 2024

AbstractThe camouflaged object segmentation model (COSM) has recently gained substantial attention due to its remarkable ability to detect camouflaged objects. Nevertheless, deep vision models are widely acknowledged to be susceptible to adversarial examples, which can mislead models, causing them to make incorrect predictions through imperceptible perturbations. The vulnerability to adversarial attacks raises significant concerns when deploying COSM in security-sensitive applications. Consequently, it is crucial to determine whether the foundational vision model COSM is also susceptible to such attacks. To our knowledge, our work represents the first exploration of strategies for targeting COSM with adversarial examples in the digital world. With the primary objective of reversing the predictions for both masked objects and backgrounds, we explore the adversarial robustness of COSM in full white-box and black-box settings. In addition to the primary objective of reversing the predictions for masked objects and backgrounds, our investigation reveals the potential to generate any desired mask through adversarial attacks. The experimental results indicate that COSM demonstrates weak robustness, rendering it vulnerable to adversarial example attacks. In the realm of COS, the projected gradient descent (PGD) attack method exhibits superior attack capabilities compared to the fast gradient sign (FGSM) method in both white-box and black-box settings. These findings reduce the security risks in the application of COSM and pave the way for multiple applications of COSM.
Heavy metal application of response surface optimized-lipopeptide biosurfactant produced by Pseudomonas aeruginosa strain CGA-02 in low-cost substrate
Authors: Anaukwu Chikodili Gladys , Ekwealor Chito Clare , Anakwenze Vivian Nonyelum , Orji Chinedu Christian , Ogbukagu Chioma Maureen , Anyaoha Victoria Ihedinachi , Isiaka Amarachukwu Bernaldine , Green Stefan Joshua , Ekwealor Ikechukwu Amechi 
Published: May 2024

AbstractCost-effective methods of biosurfactant production with minimal environmental impact are needed as global demand continues to increase. This study evaluated lipopeptide biosurfactant production in a Pseudomonas aeruginosa strain CGA-02 using a low-cost carbon substrate. The structural properties of the biosurfactant and applicability of the biosurfactant in heavy metal removal were evaluated. Response surface methodology (RSM) involving central composite design (CCD) was used to optimize process parameters to maximize biosurfactant production. The study identified sugar cane molasses and sodium nitrate as carbon and nitrogen sources of choice for bacterial growth and biosurfactant production, with a relatively 2.64-fold increase in biosurfactant yield under optimized conditions. Analysis of the biosurfactant measured a surface tension reduction of water from 72.2 ± 0.26 to 30.5 ± 0.2 mN/m at 40 mg/L critical micelle concentration. GC–MS and FTIR analysis revealed structural properties of the lipopeptide biosurfactant, with fatty acid components predominantly 9-octadecenoic acid (oleic acid), n-hexadecanoic acid, cyclotetrasiloxane and trimyristin, and infrared peaks belonging to amine, carboxyl, nitrile, alkanol, ether and carbonyl groups. Capture of heavy metals using the biosurfactant was evaluated in soil microcosms. Removal rates of 80.47, 100, 77.57, 100, and 97.57% were recorded for As, Pb, Hg, Cd and Cr respectively after 12 weeks of incubation. There was no significant difference (p < 0.05) in the removal efficiency of the biosurfactant and an analogous chemical surfactant, sodium dodecyl sulphate. First and second-order kinetic models described heavy metal removal rates by the biosurfactant. We demonstrate the production of a useful biosurfactant using low-cost waste carbon.
Comparison of microstructure, mechanical, and electrochemical performance of laser-deposited FeCrV15 alloy at varying powder feed rates
Authors: Aramide Basiru Philip , Adegbola Taoreed Adesola , Jamiru Tamba , Popoola Abimbola Patricia Idowu , Adeoti Mathew Olurotimi , Sadiku Rotimi Emmanuel 
Published: May 2024

AbstractIn the realm of surface modification, repair, and reinforcement of components exposed to challenging operational conditions, such as tillage tools, laser cladding stands out as an innovative manufacturing technique. Employing this additive manufacturing approach, a functionally graded material with outstanding strength and properties is incorporated to enhance the desired attributes of the base material. This comparative investigation scrutinized and assessed the microstructural characteristics, hardness, wear resistance, and corrosion behavior of high carbon ferrochrome FeCrV15 coatings fabricated at two distinct powder feed rates, namely 5 and 6 g/min, respectively. The analysis delved into how the resultant coatings' molten bead deposition, microstructural evolution, hardness, wear resistance, and corrosion resistance were influenced by the powder feed rate. Evaluation of hardness was conducted using a Vickers microhardness testing apparatus, while phase identification was accomplished utilizing an X-ray diffractometer. The morphologies of the microstructures were scrutinized employing optical microscopy and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). Furthermore, the corrosion response of the deposits in a soil–water environment was probed utilizing an Autolab potentiostat. A comprehensive assessment of the coatings' sliding wear performance was undertaken using an Anton Paar Tribometer. The findings of the study reveal that an escalation in the powder feed rate engenders heightened grain refinement within the microstructure, yielding a defect-free sample and augmenting the wear performance (with a wear rate of 2.42 × 10–6 mm3/N/m for sample B, surpassing 2.39 × 10–5 mm3/N/m for sample A and outstripping 1.72 × 10–3 mm3/N/m for the steel substrate). Additionally, the corrosion resistance is enhanced (with a corrosion rate of 0.0032 mm/yr for sample B, surpassing 0.0036 mm/yr for sample A, which, in turn, exceeds 0.1168 mm/yr for the steel substrate) in the case of sample B.
The expanding universe of the geometric mean
Authors: Lawson Jimmie D. , Lim Yongdo 
Published: May 2024

AbstractIn this paper the authors seek to trace in an accessible fashion the rapid recent development of the theory of the matrix geometric mean in the cone of positive definite matrices up through the closely related operator geometric mean in the positive cone of a unital $$C^*$$

C
∗

-algebra. The story begins with the two-variable matrix geometric mean, moves to the breakthrough developments in the multivariable matrix setting, the main focus of the paper, and then on to the extension to the positive cone of the $$C^*$$

C
∗

-algebra of operators on a Hilbert space, even to general unital $$C^*$$

C
∗

-algebras, and finally to the consideration of barycentric maps that grow out of the geometric mean on the space of integrable probability measures on the positive cone. Besides expected tools from linear algebra and operator theory, one observes a surprisingly substantial interplay with geometrical notions in metric spaces, particularly the notion of nonpositive curvature. Added features include a glance at the probabilistic theory of random variables with values in a metric space of nonpositive curvature, and the appearance of related means such as the inductive and power means. The authors also consider in a much briefer fashion the extension of the theory to the setting of Lie groups and briefer still to the positive symmetric cones of finite-dimensional Euclidean Jordan algebras.
The impact of community-led conservation models on women's nature-based livelihood outcomes in semi-arid Northern Ghana
Authors: Pienaah Cornelius K. A. , Baruah Bipasha , Kansanga Moses , Luginaah Isaac 
Published: May 2024

AbstractWith increasing human-induced environmental degradation, women's nature-based livelihood activities are threatened. In semi-arid northern Ghana, shea processing (i.e., shea butter, a derivative of shea nut from the shea tree), a vital women-dominated economic activity, is at risk as naturally occurring shea trees continue to decline in numbers and productivity. The decline of the shea tree's number and productivity and the ensuing biodiversity loss have sparked conservation efforts by governments and local communities. This includes community-led conservation models, which have recently gained traction in the Global South. Ghana implemented the Community Resource Management Areas (CREMA)—a community-led conservation model to improve biodiversity and ecosystem services, including shea trees conservation in response to climate change. Research has not explored the impacts of community-led conservation efforts on women’s nature-based livelihoods in Ghana. Using a mixed-methods approach involving surveys (n = 517) and focus group discussions (n = 8), this study explored shea productivity outcomes under CREMAs. Findings show that women residing in CREMAs had significantly better shea harvesting outcomes than those outside CREMAs (α = −53.725; P < 0.01). These findings demonstrate the potential for targeted conservation initiatives that are community-led, such as the CREMAs, to improve the conservation of economically significant naturally occurring trees like Shea. With the increasing impacts of climate change and environmental degradation, such models would be instrumental in achieving sustainable development goals like SDG5-gender equality, SDG10-reduced inequalities, SDG13-Climate action, SDG14-life below water, and SDG14-life on land.
Geophysical and physicochemical assessment of groundwater and the implication on the public health in rural and semi-urban areas of Northern Nigeria
Authors: Alao Joseph Omeiza , Lawal Hammed A. , Abubakar Fahad , Abdulsalami Momohjimoh 
Published: May 2024

AbstractGroundwater resource plays a central role in every sector of life globally. Unfortunately, the roles of groundwater are often unappreciated in many parts of the world, especially in developing nations. The paper applied a combined geo-electrical method and hydrochemical analysis alongside physical surveys to investigate aquifer promising zones, the quality and the source of water supply in the selected regions. The geo-electric resistivity data were used to select the most aquifer-promising zone for groundwater development with a key interest in groundwater potential and aquifer overburden protective capacity overlying the water-bearing unit. Seventeen (17) vertical electrical sounding (VES) acquired in four regions reveals that the regional weathered/fractured unit which constitutes the aquifer unity extends from 13.4 m to 41.3 m in depth with the subsurface resistivity value varying between 53 Ωm–1013 Ωm in terms of resistivity values. The overburdened thickness (protective soil layers) stretches from 2.5 m to 13 m with a resistive layer of resistivity values ranging from 111 Ωm to 2877 Ωm, which could provide high aquifer protective cover for the regional groundwater systems. The computed aquifer transmissivity and hydraulic conductivity range from 0.54 $${m}^{2}/h$$

m

2

/
h

–15.85 $${m}^{2}/h$$

m

2

/
h

, and 0.95 m/day–9.19 m/day, respectively. The estimated average longitudinal conductance (0.2 moh) reveals that the regional groundwater systems are moderately protective against surface contaminants. In addition, the physicochemical water analysis was examined, which exposes the level of heavy metals (HMs) compositions in the regional groundwater systems and the possible public health risks compared to WHO permissible drinking water limits. The sample water from the Rivers had the highest concentration of HMs (0.089 mg/I–2.012 mg/l), followed by the hand-dug wells (HWDs) (0.033 mg/l–1.555 mg/l) and the lowest in the borehole (0.011 mg/l–0.511 mg/l). In contrast, the borehole water sample shows a moderation where the HMs presence falls within the WHO standard for drinking water. The outcomes of the study show that 63% of the investigated region consumed water with a high concentration of HMs above the WHO permissible standard allowance for drinking water, while only 37% took water that falls within the WHO permissible standard. In conclusion, the study showed significant impacts of anthropogenic activities on the regional water quality, which provides vital information about the regional groundwater systems and the quality of water supply for adequate groundwater development and sustainability.