Field Test Research Articles

Association between aerobic performance and physiological responses in Yo-Yo intermittent recovery test level 2, and the futsal-specific intermittent endurance test in trained futsal players.

This prospective cross-sectional study aimed to delineate associations between the performance and physiological responses to the Bruce test with two field tests, the futsal intermittent endurance test (FIET) and the Yo-Yo intermittent recovery test level-2 (YYIR2) in elite male futsal players, in order to endorse one of field test to futsal coaches. Fifteen elite futsal players (age 20 ± 3 years) have been participated in this study. Main outcome measurements included aerobic power, heart rate, blood lactate, ventilation, VO2, VCO2, VE-VO2, and VE-VCO2 indicators during FIET, YYIR2, and the Bruce test with carrying out a portable gas analyzer. The Bruce test is significantly correlated with FIET and YYIR2 with respect to key outcome measures, including performance (r>0.59), aerobic power (r>0.69), heart rate (r>0.80), and blood lactate levels (r>0.60). The two field tests, FIET and YYIR2, were found to exhibit strong to perfect interrelationships. When examining the indicators such as VE, VO2, VCO2, VE-VO2, and VE-VCO2, moderate to strong correlations were identified across all three testing methods. However, the relationship between the Bruce test and YYIR2 was particularly noteworthy in terms of respiratory exchange ratio (RER) and metabolic equivalent of task (METS), showing a significant correlation. The YYIR2 and FIET appear to be valid practical field tests for measuring aerobic fitness and performance in competitive male futsal players.

Foxq1 activates CB2R with oleamide to alleviate POCD.

Postoperative cognitive dysfunction (POCD) is a major concern, particularly among older adults. This study used social isolation (ISO) and multiomics analyses in aged mice to investigate potential mechanisms underlying POCD development. Aged mice were divided into two groups: ISO and paired housing (PH). Oleamide and the cannabinoid receptor type 2 (CB2R) antagonist AM630 were administered intraperitoneally, while Foxq1 adeno-associated viral (AAV) vector was injected directly into the hippocampus. Intramedullary tibial surgeries were subsequently performed to establish the POCD models. Behavioral tests comprising the Y-maze, open field test, and novel object recognition were conducted 2 days after surgery. Hippocampal and serum inflammatory cytokines were assessed. Following surgery, ISO mice demonstrated intensified cognitive impairments and escalated inflammatory markers. Integrative transcriptomic and metabolomic analysis revealed elevated oleamide concentrations in the hippocampus and serum of PH mice, with associative investigations indicating a close relationship between the Foxq1 gene and oleamide levels. While oleamide administration and Foxq1 gene overexpression substantially ameliorated postoperative cognitive performance and systemic inflammation in mice, CB2R antagonist AM630 impeded these enhancements. The Foxq1 gene and oleamide may be crucial in alleviating POCD. While potentially acting through CB2R-mediated pathways, these factors may modulate neuroinflammation and attenuate proinflammatory cytokine levels within the hippocampus, substantially improving cognitive performance postsurgery. This study lays the groundwork for future research into therapeutic approaches targeting the Foxq1-oleamide-CB2R axis, with the ultimate goal of preventing or mitigating POCD.

Exploring and field-demonstrating geofence-based occupancy-centric control in residential buildings

Several studies have highlighted the thermal comfort challenges associated with occupancy-centric control (OCC) when occupants first arrive, despite OCC demonstrating energy savings potential in buildings. To address this challenge, a geofence-based OCC (Geo-OCC), where the virtual boundary of the occupant’s physical location is infused into the smart thermostat, is explored to pre-condition buildings, aiming to alleviate thermal discomfort. This research adopted an apples-to-apples field testing approach to quantify how Geo-OCC impacts the thermal comfort and energy consumption of the heating, ventilation, and air-conditioning (HVAC) system in two 1,200 ft2 lab homes located in Texas, USA. These two homes were designed and built as identically as they could be. Two side-by-side experimental scenarios were designed to compare different control strategies through integrations with smart thermostats. In scenario 1, Geo-OCC was implemented in the east home, while a baseline case without OCC (Non-OCC) was executed in the west home. In scenario 2, Geo-OCC was employed in the east home, and a traditional OCC based on occupancy presence sensors (Sensed-OCC) was implemented in the west home, demonstrating Geo-OCC’s ability to alleviate thermal discomfort. The field-testing results of scenario 1 suggested that Geo-OCC achieved a 46.41 % reduction in heating energy consumption compared to Non-OCC over the testing duration of 25 days, resulting in a maximum unmet degree (UD) of 3.83 °C in a 5-minute sampling frequency, in contrast to a maximum UD of 0.83 °C in Non-OCC mode. The results from the field testing in scenario 2 indicated that Geo-OCC reduced the maximum UD to 1.94 °C in a 5-minute sampling frequency compared to 2.28 °C in Sensed-OCC, without an increase in heating energy consumption. The results of the scenario 1 experiment suggested the OCC decreased the HVAC energy consumption while having a slightly adverse effect on thermal comfort during occupied periods, especially upon the first arrival of occupants. The field testing of scenario 2 exhibited the capability of Geo-OCC to enhance thermal comfort with minor effects on the HVAC energy consumption. In addition, Geo-OCC displayed the potential to reduce the peak demand increase caused by traditional Sensed-OCC.

Performance and economic analysis of a novel water storage tank coupled with geothermal heating System: A field test

This study tackles the underutilization of geothermal resources for building heating by introducing a novel water storage tank designed to enhance efficiency and reduce operational costs. We established a field experimental system to assess this geothermal-energy storage coupled heating system under various thermal loads, comparing its performance against traditional systems. The key findings include: (1) The novel water tank achieves release/storage ratios of over 85% under various loads, surpassing existing water storage systems and demonstrating superior performance. (2) The thermal storage efficiency exceeds 45% under all load conditions, reaching up to 100% at low loads, highlighting the tank’s crucial role in energy conservation. (3) Compared to traditional systems, the coupled heating system significantly reduces operating costs, with reductions exceeding 20% under different loads. These results indicate that the novel tank not only boosts efficiency but also offers notable economic advantages. The innovative design and its validation in the field enhance existing literature by providing a viable, efficient solution for geothermal heating, encouraging broader adoption of geothermal energy and aiding in carbon emission reduction.

Antiepileptic profile of Parawixin-11, purified from Parawixia bistriata spider venom (Araneae, Araneidae), in Wistar rats.

The pharmacological treatment of epilepsy is often complex due to the lack of efficacy in many patients and profound side effects from current drugs, including sedation, motor impairment, and teratogenesis. In the quest for new antiepileptic drugs, animal venoms offer a valuable source of neuroactive molecules targeting ion channels and neurotransmitter receptors. This study investigates the antiepileptic potential of compounds isolated from the venom of the Parawixia bistriata spider. One compound, designated Parawixin-11, demonstrated significant anticonvulsant effects when injected into the cerebral ventricle in a dose-response manner. It effectively countered seizures induced by bicuculline (ED50 0.16µg/animal), pentylenetetrazole (ED50 0.08µg/animal), strychnine (ED50 0.05µg/animal), pilocarpine (ED50 0.10µg/animal), and NMDA (ED50 0.008µg/animal). We also assessed whether intracerebroventricular administration of Parawixin-11 caused motor or cognitive impairments in rats using the open field, rotarod, and Morris water maze tests. No differences in exploration or movement were observed with doses of 0.3, 0.2, or 0.1µg of Parawixin-11. Although there was an increased latency to find the platform during the acquisition phase of the Morris water maze test, no differences in spatial memory retention were noted. Given Parawixin-11's potency against NMDA-induced seizures, we hypothesize that it may modulate the glutamatergic system, aligning with the mechanisms of several spider-derived polyamines.

Assessing and mitigating health risks of workers exposed to volatile organic compounds in contaminated soils during active pit excavation: accounting for exposure variability and uncertainty

Health risks to workers involved in the active pit excavation of volatile organic compound (VOC)-contaminated soils have been overlooked, despite the prevalence of ex-situ remediation practices in China. This study developed a new VOC exposure in pit excavation (VEPE) model that comprehensively accounts for the release of gas-phase VOCs in soil pores, surface volatilization of newly exposed agglomerates, and volatilization of newly exposed excavation pit bottom surfaces. Additionally, the model incorporates the concentration variation of soil contaminants, spatial heterogeneity of soil properties, and the variability and uncertainty of worker exposure using two-dimensional Monte Carlo simulation (2D MCS), highlighting the importance of controlling area of new exposure surfaces, soil saturation, and air exchange during the pit excavation to mitigate risks. The study evaluated worker-health-based risks during the excavation of a VOC-contaminated site in Beijing and revealed that the inhalation cancer risk for trichloroethylene (2.35×10-6) and its hazard quotient (143.92) exceed the acceptable levels (10-6 and 1.0, respectively). The comparison of models demonstrated the theoretical advancements of the VEPE model over existing pit excavation models, while the field test comparison showed a significant improvement in the predication accuracy. This study addresses the under-researched area of worker safety in contaminated excavation sites. The findings have the potential to promote cleaner and more sustainable practices in ex-situ contaminated site remediation by providing valuable insights for implementing effective control measures to mitigate the emission of toxic VOCs, thereby reducing adverse social and environmental impacts.

Experimental investigation on cooling load caused by unorganized ventilation in subway station: A case study

Unorganized ventilation significantly increases the energy consumption of subway stations. However, the quantitative description of cooling load caused by the unorganized ventilation in subway stations with platform screen doors (PSDs) still needs to be explored in depth. This study firstly proposed an experiment-based method to determine the airflow rate of unorganized ventilation, and then the corresponding cooling load is determined. Based upon this method, a series of field tests were conducted at a subway station in Shanghai. By analyzing the experimental data, the characteristic of unorganized ventilation at PSDs and entrance/exit passages was obtained. As for PSDs, the volume of unorganized ventilation in a cycle (the period from the upward train entering the station to the next upward train starting to approach the station) from the tunnel to the platform and from the platform to the tunnel is 2112.24 m3 and 4219.31 m3, respectively. With regard to entrance/exit passages, the volume of unorganized ventilation is 2655 m3 in a cycle. Thereafter, the above-mentioned results were used to determine cooling load. Owing to the difference in the departure density of train on weekdays and weekends, two typical summer days were selected for the purpose of cooling load analysis. The overall cumulative value of the cooling load caused by unorganized ventilation was 1416 kWh on a working day and 1718 kWh for the weekend, which accounted for 16.74 % and 19.19 % of the daily cooling load, respectively

Effect of the Inter-Ring Delay Time on Rock Fragmentation: Field Tests at the Underground Mine

Effect of the Inter-Ring Delay Time on Rock Fragmentation: Field Tests at the Underground Mine

Antinociceptive and anti-inflammatory activities of Ayapana triplinervis essential oil rich in thymohydroquinone dimethyl ether from Brazil.

Ayapana triplinervis (M.Vahl) R.M.King & H.Rob. (Asteraceae), popularly known as japana, is a tropical, aromatic subshrub widely used as tea to combat some diseases. The essential oil was obtained from the leaves by hydrodistillation (3h), and the chemical composition was analyzed by gas chromatography coupled to mass spectrometry. For in vivo assays, Mus musculus/Swiss mice were used to evaluate oral acute toxicological (at dose of 2000mg/kg); peripheral and central analgesic for abdominal contortion (doses of 6.25, 12.5, 25, 50 and 100mg/kg), hot plate test (12.5, 25, 50, and 100mg/kg) and formalin (25, 50 and 100mg/kg); open field test (100mg/kg); and anti-inflammatory by ear swelling induced by xylene (6.25,12.5, 25, 50, and 100mg/kg). The yield of A. triplinervis essential oil (AtEO) was 4.6%, and the oxygenated monoterpene 2,5-dimethoxy-p-cymene was the major compound in this study (63.6%). AtEO at a dose of 2,000mg/kg orally did not change the behavior patterns or mortality of the animals; liver and kidney biochemical levels were similar to the control group, indicating no liver and kidney toxicity. Moreover, AtEO, at doses of 6.25, 12.5, 25, 50, and 100mg/kg, reduced abdominal contortions by 21%, 54%, 91%, 58%, and 55%, respectively. In the hot plate test, AtEO showed a significant increase in latency time in the 60-min interval at doses of 25mg/kg (11.3 ± 3.3s) and 100mg/kg (11.9 ± 0.9s). In the first phase of the formalin test, AtEO decreased paw licking time at doses of 25, 50, and 100mg/kg, with inhibition of 22%, 38%, and 83%; in the second phase, the same doses, decreased licking time with inhibition of 24%, 34%, and 76%. AtEO did not present a significant change in the spontaneous locomotor activity of the animals. Doses of 6.25, 12.5, 25, 50, and 100mg/kg significantly reduced ear edema induced by topical application of xylene with percentages of 40%, 39%, 54%, 45%, and 45%, respectively. So, AtEO demonstrated low acute oral toxicity and exhibited significant antinociceptive and anti-inflammatory actions, consistent with the use of A. triplinervis in traditional medicine.

Is the Severity of Preoperative Eyelid Dermatochalasis Directly Correlated with Patient Satisfaction After Upper Blepharoplasty? A Prospective Study Based on PROMs.

Facial ageing, particularly in the periorbital region, is a growing concern in contemporary culture. Upper blepharoplasty, a widely performed cosmetic surgery, addresses both aesthetic and functional issues related to eyelid dermatochalasis. This study aims to investigate patient satisfaction, the relationship between satisfaction and preoperative dermatochalasis severity, and the functional impact of preoperative skin excess. A prospective study was conducted from April 2022 to April 2023, evaluating primary upper blepharoplasty outcomes. Patient-reported outcomes were measured using the FACE-Q questionnaire, assessing quality of life and satisfaction. Preoperative symptoms were evaluated using a functional questionnaire. Dermatochalasis severity was classified into three groups. Statistical analyses were performed using SPSS. Seventy-nine patients met inclusion criteria. Postoperative FACE-Q results demonstrated significant improvements in upper eyelid appraisal and satisfaction with eyes. Functional questionnaire results indicated an overall clinical improvement (p<0.01). Visual field tests showed statistically significant improvement in group 3. No correlation was found between preoperative dermatochalasis severity and postoperative aesthetic satisfaction. The study emphasizes the importance of validated questionnaires, particularly FACE-Q, in evaluating patient satisfaction and discomfort with upper lid ageing. Regardless of functional impairments, any degree of dermatochalasis may warrant treatment to ensure patient satisfaction with the cosmetic outcome. On the other hand, the functional benefits and improvements in the visual field also support the impact that the procedure has beyond purely aesthetic aspects. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Going urban: variation in personality traits of an invasive species along an urbanization gradient

Abstract The fast-growing expansion of urban areas pose severe pressures on wildlife. However, some generalist native mammals thrive in urbanized landscapes, while invasive alien species (IAS) are often more abundant in cities than in rural habitats. Variation in phenotypes—such as differences in personality traits—can influence the probability to colonize anthropized areas, especially in the case of IAS where certain traits are related to invasion success. Here, we investigated the expression of activity, exploration, and social tendency in the invasive alien Eastern Gray Squirrel (Sciurus carolinensis) in replicated study sites along a rural–urban gradient in Northern Italy. Personality traits expression was estimated using an open field test (OFT) followed by a mirror image stimulation (MIS) test. We found that squirrels were more active in urban than in suburban and rural sites, and behaved more sociable in urban than in suburban sites. Conversely, exploration did not differ along the gradient. Results also reveal the presence of a behavioral syndrome: activity (OFT), social tendency, and activity–exploration (MIS). We suggest that variation in activity level and social behavior in urban habitats could favor some species to respond positively to urbanization. This study sheds light on the underexplored personality–urbanization relationship in IAS, helping to understand the complex process of invasion.

Numerical analysis of hydrogen storage in lined rock cavern under high pressure and its implications to hydrogen embrittlement

Underground hydrogen storage could provide buffer capacity to store the excess energy from renewable resources. A lined rock cavern (LRC) is one of the hydrogen geologic storage site options. It offers great flexibility because it does not rely on the existence of salt caverns, aquifer formations or depleted hydrocarbon reservoir fields. However, many important aspects have to be investigated before its full-scale implementation, among them (1) the effect of spatial variation of rock mass properties and (2) hydrogen embrittlement on the steel lining. We present a numerical study on these two aspects by simulating field tests at a pilot LRC project. For the effect of rock heterogeneity, we assign a spatial variation of elastic properties based on the Gaussian covariance model. The results show a good agreement with the field measurements. The spatial correlation length of rock mass elastic properties only has a minor impact on the cavern surface deformation. Regarding hydrogen embrittlement, our simulations predict a significant hydrogen diffusion in the low alloy steel (S355) lining after ∼2 months of operation. The fracture simulations show little fracture propagation even after 10 years of contact with hydrogen gas. However, the product loss may be too high for the low alloy steel (S355). We would recommend the use of stainless steel to inhibit the hydrogen diffusion. We show that advanced numerical models are powerful tools to ensure the safety of hydrogen storage in LRCs.

Precise soil coverage in potato planting through plastic film using real-time image recognition with YOLOv4-tiny

Planting potatoes through plastic film with incomplete or excessive soil coverage over seed holes significantly impairs yield. Existing covering methods rely solely on mechanical transmissions, leading to bulky and inconsistent soil coverage of the seed holes. This paper reports an innovative method using a precise soil covering device based on the YOLOv4-tiny real-time object detection system to accurately identify potato plastic film holes and cover them with soil. The system adopts a lightweight and high-precision detection scheme, balancing increased network depth with reduced computation. It can identify holes in the plastic film in real-time and with high accuracy. To verify the effectiveness of YOLOv4-tiny real-time object detection system, a precise soil covering device based on this detection system has been designed and applied to a double crank multi-rod hill-drop planter. Field tests revealed that the system's average accuracy rate for detecting holes is approximately 98%, with an average processing time of 15.15 ms per frame. This fast and accurate performance, combined with the device's robust real-time operation and anti-interference capabilities during soil covering, effectively reduce the problems of soil cover omission and repeated covering caused by existing mechanical transmission methods. The findings reported in this paper are valuable for the development of autonomous potato plastic film precise soil covering devices for commercial use.

CFD and RSM Assist in Reducing the LPG Consumption of Burners for Agarwood Oil Production in Thailand

ABSTRACT This research aimed to optimize LPG consumption in Thai commercial burners used in agarwood oil production, specifically focusing on the KB-10, S-10, and EB-10 burners. Enhancing burner efficiency is crucial due to rising energy costs and environmental concerns. A dual approach using Response Surface Methodology (RSM) and Computational Fluid Dynamics (CFD) was employed in order to achieve the best burner. Central Composite Design (CCD) within the RSM framework determined the optimal swirl and inclination angles combinations. Modified burners with variant combination angles, as suggested by RSM, were numerically investigated. CFD simulations with Ansys Fluent, utilizing the k-ε turbulence and discrete ordinates (DO) radiation models, provided detailed insights into the combustion and heat transfer processes of those modified burners. The modified burners, SB10–1, SS10–3, and SEB10–7, demonstrated significant improvements. Laboratory and field tests indicated energy savings of 16.15%, 23.74%, and 20.75%, respectively. Statistical analysis confirmed these savings with p-values < .05. The 95% confidence intervals for LPG savings were 31.31 ± 0.8%, 33.42 ± 0.7%, and 31.84 ± 0.6%, corresponding to payback periods of approximately 2.99, 4.21, and 8.95 months. Additionally, CO and NOx emissions were kept below 350 ppm and 100 ppm, respectively. The novelty of this study lies in the combined use of RSM and CFD to optimize burner performance, leading to significant energy savings and emission reductions. These findings highlight the potential of these methods for burner optimization, offering both economic and environmental benefits. This research underscores the importance of integrating advanced modeling techniques to achieve sustainable and cost-effective industrial processes.

A novel strategy for design of mechanically robust antifouling coatings via bifunctional domain engineering

The issue of biofouling on marine structures carries significant economic and ecological implications, necessitating the development of effective and durable antifouling coatings. Traditional organic antifouling coatings often struggle with mechanical robustness in harsh marine environments, making them fragile and highly susceptible to abrasion. To address these challenges, we propose a novel “bifunctional domain engineering” strategy for designing robust antifouling coatings that combines excellent mechanical strength of a Fe-based amorphous layer and high antifouling efficacy of an incorporated organics. The hard domains consist of Fe-based amorphous micro humps, providing a sturdy framework that enhances the coating's mechanical durability. In contrast, the soft domains comprise epoxy resin infused with Cu2O and 4,5-Dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT), offering a dual-action antifouling function via controllable antifouling agent release. Evaluation of antifouling performance by lab tests against Pseudomonas aeruginosa, Staphylococcus aureus, and Chlorella algae and practical marine field tests (for 150 days) demonstrates significant reductions in bacterial and algal adhesion (nearly 100 % resistance) with the bifunctional domain engineered coating (referred to as HSR coating), compared to pure amorphous coating. Mechanical durability tests, including abrasion and erosion experiments, underscore the HSR coating's excellent wear resistance. Importantly, the HSR coating maintains its outstanding antifouling properties even after 1000 abrasion cycles, highlighting its potential for long-term marine applications in harsh conditions. This study lays the groundwork for design of robust antifouling coatings capable of withstanding the harsh operating environments while effectively combating biofouling.

Alpha-galactosylceramide pre-treatment attenuates clinical symptoms of LPS-induced acute neuroinflammation by converting pathogenic iNKT cells to anti-inflammatory iNKT10 cells in the brain.

Invariant natural killer T (iNKT) cells play protective or pathogenic roles in a variety of immune and inflammatory diseases. However, whether iNKT cells contribute to the progression of acute neuroinflammation remains unclear. Thus, we addressed this question with a mouse model of lipopolysaccharide (LPS)-induced acute neuroinflammation. For induction of acute neuroinflammation, wild-type (WT) C57BL/6 (B6) mice were injected intraperitoneally (i.p.) with LPS for either three or five consecutive days, and then these mice were analyzed for brain-infiltrating leukocytes or mouse behaviors, respectively. To examine the role of iNKT cell activation in LPS-induced neuroinflammation, mice were injected i.p. with the iNKT cell agonist α-galactosylceramide (α-GalCer) seven days prior to LPS treatment. Immune cells infiltrated into the brain during LPS-induced neuroinflammation were determined by flow cytometry. In addition, LPS-induced clinical behavior symptoms such as depressive-like behavior and memory impairment in mice were evaluated by the open field and Y-maze tests, respectively. We found that iNKT cell-deficient Jα18 mutant mice display delayed disease progression and decreased leukocyte infiltration into the brain compared with WT mice, indicating that iNKT cells contribute to the pathogenesis of LPS-induced neuroinflammation. Since it has been reported that pre-treatment with α-GalCer, an iNKT cell agonist, can convert iNKT cells towards anti-inflammatory phenotypes, we next explored whether pre-activation of iNKT cells with α-GalCer can regulate LPS-induced neuroinflammation. Strikingly, we found that α-GalCer pre-treatment significantly delays the onset of clinical symptoms, including depression-like behavior and memory impairment, while decreasing brain infiltration of pro-inflammatory natural killer cells and neutrophils, in this model of LPS-induced neuroinflammation. Such anti-inflammatory effects of α-GalCer pre-treatment closely correlated with iNKT cell polarization towards IL4- and IL10-producing phenotypes. Furthermore, α-GalCer pre-treatment restored the expression of suppressive markers on brain regulatory T cells during LPS-induced neuroinflammation. Our findings provide strong evidence that α-GalCer-induced pre-activation of iNKT cells expands iNKT10 cells, mitigating depressive-like behaviors and brain infiltration of inflammatory immune cells induced by LPS-induced acute neuroinflammation. Thus, we suggest the prophylactic potential of iNKT cells and α-GalCer against acute neuroinflammation.

Research on the mechanism and control of roof deformation in gob-side entry retaining of close-distance coal seams

Multiple mining operations in close-distance coal seams (CDCSs) can reduce the integrity and bearing capacity of the surrounding rock, leading to roof fracturing and widespread subsidence in gob-side entry retaining (GER). This highlights the critical need for research on roof control technology. For this purpose, adopting the panel of the Xinchazhuang Coal Mine (the distance between two coal seams is 7.3 m) as the engineering background, a theoretical model of GER of CDCSs was established on the basis of the surrounding rock structure and roof rock movement characteristics, and the roof failure deformation mechanism was examined. The roof failure deformation encompasses two parts: rotational sinking of roof rock blocks and roof separation deformation. To achieve roof control, a strategy involving optimized roof cutting and higher preload cables was suggested. The impacts of key roof control parameters on roadway deformation were examined and compared by numerical simulation studies. The findings showed that optimized roof cutting resulted in a 21.1 % reduction in the roof stress, whereas the use of roof cables with higher preload levels resulted in a 55.1 % decrease in roadway deformation, effectively mitigating rotational sinking and roof separation deformation. The field tests demonstrated that the optimized scheme facilitated roof integrity preservation, and the maximum deformation of the roof reached 98 mm, a decrease of 68.5 % on average from that in the original scheme. These research results could provide a reference for roof support in CDCSs roadways under similar geological conditions.

Study on the Damage Evolution and Failure Mechanism of Floor Strata under Coupled Static-Dynamic Loading Disturbance

In the field test, we found that the failure depth of the goaf floor strata tends to be further because the periodic breaking and caving of the immediate roof, upper roof, and roof key stratum has dynamic stress disturbance effects on the floor. To further analyze its formation mechanism, this paper studies the damage evolution and fracture mechanism of goaf floor rock under the coupled static-dynamic loading disturbance caused by roof caving, based on the stress distribution state, the damage evolution equation of coal measure rock, the damage constitutive model, and the fracture criterion of floor rock. The main conclusions are listed as follows: 1. Based on the mining floor stress distribution, the floor beam model establishes the response mechanism of floor rock stress distribution. Also, the equation of stress distribution at any position in floor strata under mining dynamic load is given. 2. Combining the advantages of Bingham and the Generalized-Boydin model, the B-G damage constitutive model is established, which can describe the constitutive characteristics of coal measure rock under the coupled static-dynamic loading disturbance well. Furthermore, the variation law of parameters changing with strain rate is analyzed. 3. According to the twin-shear unified strength yield theory and the B-G damage constitutive model, coal measure rock’s twin-shear unified strength damage fracture criterion is established. Finally, the stress distribution expression of floor strata under concentrated and uniform dynamic loads is introduced, and the fracture criterion of goaf floor strata under a coupled static-dynamic loading disturbance is proposed.

Non-syndromic OTX2-associated pattern dystrophy: a 10-year multimodal imaging study.

To report novel multimodal imaging features and long-term follow-up of Orthodenticle Homeobox 2 (OTX2)-associated pattern Gdystrophy. A 14-year-old boy referred with glaucoma suspect and macular pigmentation underwent fundus autofluorescence imaging, optical coherence tomography, fluorescein and indocyanine green angiography, visual field test, microperimetry and electrophysiology over a ten-year period. Next-generation sequencing panel identified a de novo heterozygous likely pathogenic OTX2 variant, c.259G>A, [p.(Glu87Lys)]. Visual acuity was 20/40 OD and 20/30 OS. Examination showed bilateral enlarged optic nerve heads and increased disc cupping, multiple cilioretinal arteries, a pigmentary maculopathy with stellate-shaped region of hypoautofluorescence, shallow serous macular detachment, subretinal deposits and temporal avascular retina. Angiography showed no source of leakage and absence of retinal neovascularisation despite extensive peripheral non perfusion. Electrophysiological assessments demonstrated mild progressive rod and cone pathway abnormalities, reduced light-adapted b:a ratio, and reduced Arden ratio on electro-oculogram. Ten-year follow-up confirmed a stable disease course despite persistent submacular fluid. There was no associated pituitary structural abnormality or dysfunction. This case study contributes to further understanding of OTX2-associated pattern dystrophy, highlighting its stability over 10 years. Further investigation into inter-individual and intrafamilial variability is warranted.

Quinacridones as a Building Block for Sustainable Gliding Layers on Ice and Snow

Quinacridone (QA) and 2,9-dimethylquinacridone (DQA) are synthetic substances suitable as a hard, abrasion-resistant, self-organizing gliding layer on ice and snow. For sustainable use, a large number of parameters must be considered to demonstrate that these non-biogenic substances and their by-products and degradation products are harmless to humans and the environment in the quantities released. For this task, available experimental data are used and supplemented for all tautomers by numerous relevant physical, chemical, toxicological and ecotoxicological estimated values based on various Quantitative Structure Activity Relationship (QSAR) methods. On the one hand, the low solubility of QA and DQA leads to stable gliding layers and thus, low abrasion and uptake by plants, animals and humans. On the other hand, the four hydrogen bond forming functional groups per molecule allow nanoparticle decomposition and enzymatic degradation in natural environments. All available data justify a sustainable use of QA and DQA as a gliding layer. The assessment of the toxicological properties is complemented by an investigation of the size and morphology of DQA particles, as well as field tests indicating excellent performance as a gliding layer on snow.