Search Results (22)

In the extreme climate of Punta Arenas, in southern Chile, Energy Poverty (EP) has been historically addressed via a gas subsidy for heating and a discount considering the dwelling’s value, reducing the price paid by the homes by around 70% compared to the national average, albeit without intervention measures for the low thermal performance of the housing stock built before 2000. This study sought to evaluate the technical, economic, and fiscal feasibility of replacing consumption subsidies with thermal retrofitting. A representative standard dwelling (V4, 114 m²) was modeled using dynamic simulation in DesignBuilder/EnergyPlus and calibrated against monthly gas consumption (July 2024–June 2025) using normalized mean bias error (NMBE) and the coefficient of variation in the root-mean-square error (CV(RMSE)) according to ASHRAE Guideline 14. The baseline and retrofitted scenarios were compared and extrapolated to the pre-2000 stock of 38,605 homes at coverage levels of 0%, 20%, 50%, and 80%. In the standard dwelling, the annual consumption decreased from 5181.5 to 702.5 m³/year (49,224 to 6674 kWh/year), a decrease of 86.4%. On an overall scale, aggregate consumption fell from 1820 GWh/year (0%) to 1562, 1090, and 608 GWh/year at 20%, 50%, and 80% coverage, respectively. With an investment of US$25,289.00 and annual fiscal savings of US$6458.54, the net present value is US$49,470.36, and the benefit/cost ratio is 2.96 over 20 years (6% discount rate), indicating that investment in the housing stock’s performance consistently reduces vulnerability and fiscal pressure. Full article

Background/Objective: Preterm birth poses notable neurodevelopmental risks, with cerebral microcirculatory disturbances potentially contributing to long-term impairment. Existing monitoring modalities lack bedside capacity to evaluate these microvascular changes during critical brain development. We characterized cerebral microperfusion and functional maturation patterns in preterm versus full-term neonates using combined ultra-micro angiography (UMA) and an amplitude-integrated electroencephalogram (aEEG). Methods: In this prospective study, 76 neonates (23 extremely/very preterm [EP/VPT], 27 moderate-late preterm, and 26 term controls) were assessed at term-equivalent age. UMA helped quantify regional microperfusion (color pixel percentage, abbreviated as CPP in this context to differentiate from cerebral perfusion pressure), whereas aEEG (Burdjalov scores) helped evaluate functional maturation at 37–38 and 40 weeks’ postmenstrual age. Results: EP/VPT infants demonstrated significant cerebral hyperperfusion with distinct cortex–white matter perfusion gradients. Although preterm infants showed advanced aEEG maturation at 37–38 weeks, this difference normalized by 40 weeks. Conclusion: Gestation-dependent cerebral hyperperfusion and transient EEG maturation differences in EP/VPT infants at term-equivalent age support the value of UMA–aEEG integration for neurovascular assessment. The observed perfusion–EEG patterns suggest prematurity-specific neuroadaptation, warranting further investigation of long-term functional correlates. Full article

Background: Probiotic supplementation for very preterm infants is a common practice in many neonatal units. Assessing the effects of early postnatal exposure to probiotics on long-term neurodevelopment, growth, and atopy-related outcomes is important. Extremely preterm (EP: <28 weeks) infants enrolled in our previously reported randomized trial (SiMPro) comparing short-term effects of single (SS: B. breve M-16V) versus triple-strain (TS: B. breve M-16V, B. longum subsp. infantis-M63, B. longum subsp. longum-BB536) probiotic provided a unique opportunity to study this issue. Methods: This follow-up study assessed the five-year outcomes of SiMPro trial infants, including neurodevelopment (cognition (Full Scale Intelligence Quotient/ FSIQ using WPPSI-IV), behavior (Strengths and Difficulties Questionnaire), executive function (BRIEF–P)), growth (anthropometry) and blood pressure (BP). Atopy-related outcomes were evaluated at six to seven years using the ISAAC questionnaire. A linear mixed model was used for longitudinal outcomes. Impairment indicators were modeled using logistic regression and adjusted for Socio-Economic Indexes for Areas (SEIFA) centiles. Results: Follow-up rates (SS: 89.2% versus TS: 95%), neurodevelopmental outcomes [severe impairment (FSIQ < 70): SS: 7.4% versus TS: 4.3%; p = 0.68], growth, BMI, and BP were comparable between the SS and TS groups. The total difficulty score or BRIEF–P executive indices, disability rates (none: 66.7% versus 55.4%), and atopy-related outcomes were comparable between groups. Conclusions: Both TS and SS Bifidobacterium probiotic formulations were safe, with comparable neurodevelopmental, growth, and atopy-related outcomes at school age. Full article

The stability of nanolubricants is critical for ensuring effective performance under extreme pressure (EP) conditions, where severe boundary lubrication governs friction and wear behaviour. This study examines palm kernel oil (PKO)-based nanolubricants enhanced with carbon graphene (CG), hexagonal boron nitride (hBN), and molybdenum disulfide (MoS₂), with and without oleic acid (OA) as a surfactant. OA incorporation improved CG dispersion stability, reducing agglomerate size by 30.4% (17.61 μm to 12.23 μm) and increasing the viscosity index from ~176 to 188, compared to 152 for the commercial hydrogen engine oil baseline. Under EP conditions, PKO + CG + OA achieved a 51.7% reduction in the coefficient of friction (0.58 to 0.28) and 18.2% improvement in weld load resistance, while wear scar diameter decreased by 13.4%. Surface and elemental analyses indicated the formation of a composite tribofilm containing oxide species, graphene platelets, and carboxylate-derived compounds from OA, consistent with iron–oleate-like chemistry that enhances load-carrying capacity and wear protection. These findings demonstrate the potential of OA-assisted PKO nanolubricants as sustainable, high-performance formulations for extreme pressure boundary lubrication, contributing to the advancement of green tribology. Full article

The classic four-ball test was developed in the 1930s and has remained unchanged to this day. This versatile and widely used methodology would benefit from further development with modern tools and techniques. The classic four-ball test is traditionally performed with load steps, which makes it slow, and determining the exact last non-seizure load is quite challenging. To overcome this situation, a new methodology for testing the high-pressure properties (EP) of greases and oils is presented, using a continuous, constant-load ramp rate. The peak in the evolution of the coefficient of friction represents the occurrence of the last non-seizure sliding. The load at which the final non-seizure sliding occurs is defined as the last non-seizure load (LNSL). The obtained results are consistent with historical experience with “classic” four-ball EP tests, and the test procedure is fast and highly repeatable. Full article

The lubricating properties of three secondary amides were evaluated using the four-ball apparatus method. It was found that the studied amides—N-propylpropanamide (AC3C3), N-propyloctanamide (AC3C8), and N-propyldodecanamide (AC3C12)—could be a promising group of new AW/EP (anti-wear/extreme-pressure) additives for lubricants, especially for silica-thickened greases. Of the amides tested, AC3C8 was found to have the best properties. The synthesized amide structures were immobilized on SBA-15 nanosilica and examined as described above. Notably, SBA-15 has not previously been reported as a potential lubricant additive. The results of the tribological tests showed that SBA-15-immobilized amides performed better than non-immobilized amides. Nevertheless, the lack of stability of the amide-grafted SBA-15 when dispersed in oil limits its use in targeted formulations and should be improved through further research. By testing a silica-thickened grease, a synergistic effect was observed between the free-amide AC3C8 and a commercially available additive containing butylated triphenyl phosphate. A 240% increase in the Goz40 parameter (anti-wear properties) and a 150% increase in welding load (extreme-pressure properties) were obtained with the addition of 2%w/w of commercial additive and 3%w/w of AC3C8 to a base oil. Full article

Identifying the relationship between extreme precipitation (EP) and large-scale climate circulation is of great significance for extreme weather management and warning. Previous studies have effectively revealed the influence of single climate circulation on EP, although the influence characteristics of multiple climate circulation are still unclear. In this study, seasonal spatiotemporal changes in decadal anomalies of daily EP were analyzed based on quantile perturbation method (QPM) within the Three Gorges Reservoir Area (TGRA) for the period from 1960 to 2020. Sea surface temperature (SST)- and sea level pressure (SLP)-related climate circulation factors were selected to examine their interaction influences on and contributions to EP. The results showed that: (1) Summer EP anomalies exhibited greater temporal variability than those in other seasons, with the cycle duration of dry/wet alternation shortening from 15 years to 5 years. Winter EP anomalies showed pronounced spatial homogeneity patterns, especially in the 1970s. (2) According to the analysis based on a single driver, the Southern Oscillation Index (SOI), the North Atlantic Oscillation (NAO), and the Indian Ocean Dipole (IOD) had prolonged correlations with seasonal EP anomalies. (3) More contributions can be obtained from multiple climate circulations (binary and ternary drivers) on seasonal EP anomalies than from a single driver. Although difference existed in seasonal combinations of ternary factors, their contributions on EP anomalies were more than 60%. This study provides an insight into the mechanisms of modulation and pathways influencing various large-scale climate circulation on seasonal EP anomalies. Full article

The harmful effects of wear can be reduced through proper lubrication of the frictional parts. When exposed to excessive loads, the lubricant film is displaced from the surfaces, and even the adhesive lubricant layer may rupture. Additives known as Extreme Pressure (EP) are frequently incorporated into lubricants to minimise wear and avert seizures under high temperature and pressure. Mechanistically, these additives generate a film on the surface through chemisorption. These additives are extensively applied in various lubricants, with the largest quantities being employed in metalworking fluids and lubricating greases. Sulfurized vegetable oils and their derivates can be used as EP additives for lubricants. To conduct the investigations, sulfurized additives were synthesized using different vegetable-based oils and fatty acid esters, and alpha-olefins. In this study, the Four-ball test results were compared to gain a more accurate comprehension of how various raw-material-based additives influence wear and friction. The goal was to select raw materials that could be used with favorable results for the production of EP additives. The objective was to achieve a minimum Four-ball weld load parameter of 2000 N. The experiments revealed that the functional impacts of the synthesized samples are dependent on the type of raw materials employed. Based on the experimental data and the stated criteria, the examined raw materials were found to be suitable for the synthesis of EP additives. Full article

The content of Cu²⁺ in lubricants is an essential indicator for determining the quality of the lubricant and predicting mechanical failure. Finding an effective and sensitive method for detecting Cu²⁺ in lubricants is of great importance in oil monitoring. In this work, AgInS₂ (AIS) and AgInS₂-ZnS (ZAIS) nanoparticles (NPs) were synthesized by a simple one-step approach via in-situ surface modification by oleylamine. The as-synthesized AIS and ZAIS NPs exhibit good dispersion stability in various apolar media. The photoluminescence (PL) of AIS and ZAIS NPs as lubricating additives could reflect and monitor the lubrication state of steel-copper pairs due to the quenching effect of Cu²⁺ from the friction process. With an optimum concentration of 0.5 wt% in paraffin oil, the friction coefficient of the AIS and ZAIS NPs at 100 N was decreased by 56.8 and 52.1% for steel-steel contacts, respectively. ZAIS was observed to be more effective than AIS in improving anti-wear (AW) and extreme pressure (EP) properties, with a load-bearing capacity of up to 1100 N. Characterization of the wear tracks by SEM and XPS indicates that a tribofilm composed of metal sulfides and oxides was formed during the lubricating process. This work not only reveals AIS and ZAIS NPs as a new class of promising candidates for lubricating additives but also unveils their potential for monitoring lubricant conditions and exploring lubricant service life. Full article

Water-based lubrication, due to the poor film-forming ability of water, faces challenges in achieving effective lubrication for titanium alloys. This study systematically investigates the frictional performance of phosphorus-based extreme pressure (EP) additives and self-emulsifying esters (SEE) on the surface of titanium alloy (TB6) under different pressures and temperatures. The core lubricant consists of SEE with nonylphenol polyoxyethylene ether phosphate ester (NPEP), polyoxyethylene oleyl ether phosphate ester (POEP), and alcohol ether phosphate ester (AEP). Results show that SEE significantly improves the film-forming ability of the aqueous solution, while phosphate ester forms a strong chemical adsorption film on the alloy surface via P-O-Ti covalent bonds, enhancing the strength of the lubricating film. The combination of SEE and phosphate esters in the water-based solution enables effective lubrication for titanium alloys. Particularly, the mixture of POEP and SEE demonstrates excellent synergistic effects, making it an ideal blend for water-based cutting fluids for titanium alloys. This study elucidates the lubrication mechanisms and action ranges between different additives, providing important guidance for the development and promotion of water-based cutting fluids. Full article

Vegetable oils have been used as metalworking fluids (MWFs) for many years, particularly in small-scale metalworking operations and in industries where environmental regulations are strict. Before the development of modern MWFs, vegetable oils were one of the most common lubricants used for metalworking tools. The use of vegetable oils can be traced back to ancient civilizations such as Egypt, Greece, and Rome, where olive oil was commonly used to lubricate metal tools and weapons. Today, vegetable oils are used as MWFs in a variety of applications. They are often combined with additives or nanoparticles to enhance their performance, such as improving the lubricity, cooling properties, and stability of the oil, as well as reducing friction and wear on the cutting tool. Additives, such as antioxidants, anti-wear agents, and extreme pressure (EP) additives, can be used to improve the performance of vegetable oils as cutting fluids. Compared to standard MWFs, vegetable oils are generally more biodegradable and environmentally friendly, and can be more cost-effective. However, MWFs may offer superior performance in certain areas, such as lubrication and cooling. Ultimately, the choice of MWFs will depend on the specific requirements of the metalworking operation and the balance between performance, cost, and environmental considerations. As the demand for sustainability and environmental responsibility continues, the use of vegetable oils as MWFs is likely to become even more popular in the future. Overall, vegetable oils offer a viable and potentially attractive alternative to standard MWFs in certain applications. This review highlights both conventional and most recent advances in vegetal oils frequently used as lubricant fluids in manufacturing processes. Full article

The present work demonstrates the novel composition of nanoparticles (NPs) of polyaniline (PANI) solo and, in combination with particles of polytetrafluoroethylene (PTFE) ~230 nm, as a powerful additive (antiwear-AWA and extreme-pressure additive EPA) in lubricating oils. The concentration of PANI NPs varied from 1–4 wt.% in a base oil and commercial 5W30 engine oil. The tribo-performance was evaluated on a four-ball tester. The PANI-based oils significantly enhanced the load-bearing ability, and 3 wt.% of PANI NPs led to enhancement in EP properties by 220% in a base oil and 58% in engine oil. Additionally, hybrid combinations of NPs of PTFE with PANI in base oil were prepared by mixing in a ratio of 3:1 and 2:1 and were explored for possible tribo-synergism in EP properties. The hybrid nano-oils led to the highest reported ~ 535% enhancement in the load-carrying capacity of mineral oil. The lubrication mechanisms for enhanced tribo performance were linked with studies on a scanning electron microscope, an energy-dispersive X-ray analyzer, and with the use of Raman spectroscopy. Full article

Autumn is the transitional season when the atmospheric circulation pattern changes from summer to winter. The temperature and precipitation in Southeastern China in autumn are significantly influenced by the change in circulation patterns, and both show significant uniqueness. The clustering method can be used to observe the changes of circulation patterns in detail and to observe and analyze the transition from warm to cold seasons from a detailed view of the daily circulation pattern perspective. This method may have important research implications on how to study the generation and dissipation of extreme weather events. The Self-Organizing Maps (SOM) method is used to a 500 hPa geopotential height and 850 hPa wind and sea level pressure for 1981–2020 to identify the characteristic weather patterns (WTs) in autumn (September–November) over Southeastern China. Characteristics of the captured WTs are also analyzed in terms of the distribution characteristics of weather patterns, occurrence frequency, typical progression, precipitation and extreme precipitation (EP), temperature and extreme high temperature (EHT), and the relationship with atmospheric teleconnection. Nine WTs were identified in autumn, which represents a series of weather situations consisting of troughs and ridges. On this basis, these WTs were used to carry out the differentiation of seasonal differences between early and late autumn. The maximum mean and extreme precipitation occur in several early season patterns (WT1, WT2, WT4, and WT7). It is highly likely that extremely high temperatures occur in the WT1 and WT2 patterns. The most common progression between WTs is WT7−WT1−WT2−WT4 in the early season. This seasonality allows us to distinguish between early and late seasons based on daily weather types. A preliminary trend analysis suggests that patterns in the early season occur more frequently and last longer in the early season, and patterns in the late season occur less frequently and later. That is, the longer cool season pattern is shifting to the shorter warm season pattern. In addition, the persistence of both cool and warm patterns increased during 2001–2020 relative to 1981–2000, and the risk of both flooding and drought occurrence is on the rise. Full article

As the contamination of cereal grains with ergot has been increasing in Western Canada, studies were undertaken to evaluate the impacts of heating (60, 80, 120, or 190 °C) alone or in combination with pelleting on concentrations of ergot alkaloids. Fifteen samples of ergot-contaminated grain from Alberta and Saskatchewan were assayed for R and S epimers of six alkaloids (ergocryptine, ergocristine, ergocornine, ergometrine, ergosine, and ergotamine) using HPLC MS/MS. Five samples with distinct alkaloid profiles were then selected for heating and pelleting studies. Heating resulted in a linear increase (p < 0.05) of total R and total S epimers with increasing temperature, although some individual R epimers were stable (ergometrine, ergosine, ergotamine). Pelleting also increased (p < 0.05) concentrations of total R and total S epimers detected, although ergometrine concentration decreased (p < 0.05) after pelleting. A feeding study arranged in a 2 × 2 factorial structure used 48 backgrounding Angus-cross steers fed four different diets: (1) Control Mash (CM, no added ergot), (2) Control Pellet (CP), (3) Ergot Mash (EM), or (4) Ergot Pellet (EP). Pelleting heated the ergot to 90–100 °C under 4 bars pressure, but the ergot used in the feeding study was not otherwise heated. Alkaloid concentrations of EM and EP varied by up to 1.1 mg/kg depending on the feed matrix assayed. No differences among treatments were noted for growth performance, feed intake, feed conversion, concentrations of serum prolactin and haptoglobin, hair cortisol, or in temperatures of extremities measured by infrared thermography. The only negative impacts of ergot alkaloids were on blood parameters indicative of reduced immune function or chronic inflammation. Pelleting did not heighten the negative clinical outcomes of ergot, although alkaloid concentrations of pelleted feed increased depending on the matrix assayed. It was hypothesized that the heat and pressure associated with pelleting may enhance the recovery of alkaloids from pelleted feed. Full article

This study evaluates the tribological performance of nanolubricants of a vegetable oil (sunflower oil) reinforced with different concentrations of environmentally-friendly nanoparticles of halloysite clay nanotubes (HNTs). Tribological characterization was performed under different conditions to determine its effect on the nanolubricants’ performance and optimal HNT concentration. The tribological performances under low and high contact pressures were analyzed with a block-on-ring tribometer following the ASTM G-077-05 standard procedure. The extreme pressure (EP) properties of the nanolubricants were determined with a T-02 four-ball tribotester according to the ITeE-PIB Polish method for testing lubricants under scuffing conditions. In addition, the lubrication performance of the newly-developed vegetable oil-based nanolubricants was evaluated in an industrial-type application through a tapping torque test. The results indicated that at a low contact pressure 1.5 wt.% HNTs/sunflower oil provided the best tribological behavior by decreasing the coefficient of friction (COF) and wear volume loss by 29 and 70%, respectively. For high contact pressures, 0.05 wt.% HNTs lowered COF and wear by 55% and 56%, respectively. The load-carrying capacity increased by 141% with 0.10 wt.% HNTs compared to the sunflower oil. A high tapping torque efficiency was obtained with HNTs that can prolong tool life in the machining process. Therefore, this study suggests that HNTs/sunflower oil could be used as green lubricants for industrial applications. Full article