•Plastic debris were sampled from 25 beaches at the Pearl River Estuary.•Expanded polystyrene debris represented a vast majority of the samples.•The mean abundance of microplastic debris was higher ...than international averages.•Spatial distribution of debris indicated the Pearl River as a potential source.
Large plastic (>5mm) and microplastic (0.315–5mm) debris were collected from 25 beaches along the Hong Kong coastline. More than 90% consisted of microplastics. Among the three groups of microplastic debris, expanded polystyrene (EPS) represented 92%, fragments represented 5%, and pellets represented 3%. The mean microplastic abundance for Hong Kong was 5595items/m2. This number is higher than international averages, indicating that Hong Kong is a hotspot of marine plastic pollution. Microplastic abundance was significantly higher on the west coast than on the east coast, indicating that the Pearl River, which is west of Hong Kong, may be a potential source of plastic debris. The amounts of large plastic and microplastic debris of the same types (EPS and fragments) were positively correlated, suggesting that the fragmentation of large plastic material may increase the quantity of beach microplastic debris.
Identification of runner’s performance level is critical to coaching, performance enhancement and injury prevention. Machine learning techniques have been developed to measure biomechanical ...parameters with body-worn inertial measurement unit (IMU) sensors. However, a robust method to classify runners is still unavailable. In this paper, we developed two models to classify running performance and predict biomechanical parameters of 30 subjects. We named the models RunNet-CNN and RunNet-MLP based on their architectures: convolutional neural network (CNN) and multilayer perceptron (MLP), respectively. In addition, we examined two validation approaches, subject-wise (leave-one-subject-out) and record-wise. RunNet-MLP classified runner’s performance levels with an overall accuracy of 97.1%. Our results also showed that RunNet-CNN outperformed RunNet-MLP and gradient boosting decision tree in predicting biomechanical parameters. RunNet-CNN showed good agreement (R2 > 0.9) with the ground-truth reference on biomechanical parameters. The prediction accuracy for the record-wise method was better than the subject-wise method regardless of biomechanical parameters or models. Our findings showed the viability of using IMUs to produce reliable prediction of runners’ performance levels and biomechanical parameters.
Surface ozone (O3) is an important air pollutant and
greenhouse gas. Land use and land cover is one of the critical factors
influencing ozone, in addition to anthropogenic emissions and climate. Land
...use and land cover change (LULCC) can on the one hand affect ozone
“biogeochemically”, i.e., via dry deposition and biogenic emissions of
volatile organic compounds (VOCs). LULCC can on the other hand alter
regional- to large-scale climate through modifying albedo and
evapotranspiration, which can lead to changes in surface temperature,
hydrometeorology, and atmospheric circulation that can ultimately impact
ozone “biogeophysically”. Such biogeophysical
effects of LULCC on ozone are largely understudied. This study investigates
the individual and combined biogeophysical and biogeochemical effects of
LULCC on ozone and explicitly examines the critical pathway for how LULCC
impacts ozone pollution. A global coupled atmosphere–chemistry–land model is
driven by projected LULCC from the present day (2000) to the future (2050) under
RCP4.5 and RCP8.5 scenarios, focusing on the boreal summer. Results reveal
that when considering biogeochemical effects only, surface ozone is
predicted to have slight changes by up to 2 ppbv maximum in some areas due
to LULCC. It is primarily driven by changes in isoprene emission and dry
deposition counteracting each other in shaping ozone. In contrast, when
considering the combined effect of LULCC, ozone is more substantially
altered by up to 5 ppbv over several regions in North America and Europe
under RCP4.5, reflecting the importance of biogeophysical effects on ozone
changes. In boreal and temperate mixed forests with intensive reforestation,
enhanced net radiation and sensible heat induce a cascade of
hydrometeorological feedbacks that generate warmer and drier conditions
favorable for higher ozone levels. In contrast, reforestation in subtropical
broadleaf forests has minimal impacts on boundary-layer meteorology and
ozone air quality. Furthermore, significant ozone changes are also found in
regions with only modest LULCC, which can only be explained by “remote”
biogeophysical effects. A likely mechanism is that reforestation induces a
circulation response, leading to reduced moisture transport and ultimately
warmer and drier conditions in the surrounding regions with limited LULCC.
We conclude that the biogeophysical effects of LULCC are important pathways
through which LULCC influences ozone air quality both locally and in remote
regions even without significant LULCC. Overlooking the effects of
hydrometeorological changes on ozone air quality may cause underestimation
of the impacts of LULCC on ozone pollution.
Systemic candidal infections are a common problem in hospitalized patients due to central venous catheters fabricated using silicone biomaterial (SB). We therefore evaluated the effect of human serum ...on C. albicans biofilm morphology, growth, and the expression of virulence-related genes on SB in vitro.
We cultivated C. albicans SC5314 (wild-type strain, WT) and its derivative HLC54 (hyphal mutant, HM) for 48 h in various conditions, including the presence or absence of SB discs, and human serum. The growth of planktonic and biofilm cells of both strains was monitored at three time points by a tetrazolium salt reduction assay and by scanning electron microscopy. We also analyzed by RT-PCR its expression of the virulence-related genes ALS3, HWP1, EAP1, ECE1, SAP1 - SAP10, PLB1, PLB2, PLC and PLD.
At each time point, planktonic cells of WT strain cultured in yeast nitrogen base displayed a much higher expression of EAP1 and HWP1, and a moderately higher ALS3 expression, than HM cells. In planktonic cells, expression of the ten SAP genes was higher in the WT strain initially, but were highly expressed in the HM strain by 48 h. Biofilm growth of both strains on SB was promoted in the presence of human serum than in its absence. Significant upregulation of ALS3, HWP1, EAP1, ECE1, SAP1, SAP4, SAP6 - SAP10, PLB1, PLB2 and PLC was observed for WT biofilms grown on serum-treated SB discs for at least one time point, compared with biofilms on serum-free SB discs.
Human serum stimulates C. albicans biofilm growth on SB discs and upregulates the expression of virulence genes, particularly adhesion genes ALS3 and HWP1, and hydrolase-encoding genes SAP, PLB1 and PLB2. This response is likely to promote the colonization of this versatile pathogen within the human host.
Total knee arthroplasty (TKA) is a cost-effective procedure, but it is also associated with substantial postoperative pain. The present study aimed to compare pain relief and functional recovery ...after TKA among groups that received intravenous corticosteroids, periarticular corticosteroids, or a combination of both.
This randomized, double-blinded clinical trial in a local institution in Hong Kong recruited 178 patients who underwent primary unilateral TKA. Six of these patients were excluded because of changes in surgical technique; 4, because of their hepatitis B status; 2, because of a history of peptic ulcer; and 2, because they declined to participate in the study. Patients were randomized 1:1:1:1 to receive placebo (P), intravenous corticosteroids (IVS), periarticular corticosteroids (PAS), or a combination of intravenous and periarticular corticosteroids (IVSPAS).
The pain scores at rest were significantly lower in the IVSPAS group than in the P group over the first 48 hours (p = 0.034) and 72 hours (p = 0.043) postoperatively. The pain scores during movement were also significantly lower in the IVS and IVSPAS groups than in the P group over the first 24, 48, and 72 hours (p ≤ 0.023 for all). The flexion range of the operatively treated knee was significantly better in the IVSPAS group than in the P group on postoperative day 3 (p = 0.027). Quadriceps power was also greater in the IVSPAS group than in the P group on postoperative days 2 (p = 0.005) and 3 (p = 0.007). Patients in the IVSPAS group were able to walk significantly further than patients in the P group in the first 3 postoperative days (p ≤ 0.003). Patients in the IVSPAS group also had a higher score on the Elderly Mobility Scale than those in the P group (p = 0.036).
IVS and IVSPAS yielded similar pain relief, but IVSPAS yielded a larger number of rehabilitation parameters that were significantly better than those in the P group. This study provides new insights into pain management and postoperative rehabilitation following TKA.
Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.
The effects of microplastic concentrations (10itemsl−1 and 1000itemsl−1) on the physiological responses of Atactodea striata (clearance rate, absorption efficiency, respiration rate) were ...investigated. The fates of ingested microplastics and the efficiency of depuration in removing ingested microplastics were also studied. A. striata ingested microplastics and the clearance rate was reduced at high concentration of microplastics. Since the respiration rate and absorption efficiency remained unchanged in exposed A. striata, reduction in the clearance rate would reduce the energy intake. Ingestion and retention of microplastics in the body were further limited by the production of pseudofaeces and faeces, and depuration in clean water, resulting in a very small amount of microplastics stored in the body of the clam.
Microorganisms employ quorum sensing (QS) mechanisms to communicate with each other within microbial ecosystems. Emerging evidence suggests that intraspecies and interspecies QS plays an important ...role in antimicrobial resistance in microbial communities. However, the relationship between interkingdom QS and antimicrobial resistance is largely unknown. Here, we demonstrate that interkingdom QS interactions between a bacterium, Pseudomonas aeruginosa and a yeast, Candida albicans, induce the resistance of the latter to a widely used antifungal fluconazole. Phenotypic, transcriptomic, and proteomic analyses reveal that P. aeruginosa's main QS molecule, N-(3-Oxododecanoyl)-L-homoserine lactone, induces candidal resistance to fluconazole by reversing the antifungal's effect on the ergosterol biosynthesis pathway. Accessory resistance mechanisms including upregulation of C. albicans drug-efflux, regulation of oxidative stress response, and maintenance of cell membrane integrity, further confirm this phenomenon. These findings demonstrate that P. aeruginosa QS molecules may confer protection to neighboring yeasts against azoles, in turn strengthening their co-existence in hostile polymicrobial infection sites.
Since idiopathic scoliosis is a multifactorial disorder, the proprioceptive defect is considered one of its etiological factors. Genetic studies have separately revealed this relationship, yet it ...remains indeterminate which specific genes that related to proprioception contributed to the initiation, progression, pathology, and treatment outcomes of the curvature. A systematic search was conducted on four online databases, including PubMed, Web of Science, Embase, and Academic search complete. Studies were included if they involved human or animal subjects with idiopathic scoliosis and evaluated with proprioceptive genes. The search period was the inception of the database to February 21, 2023. Four genes (i.e., Ladybird homeobox 1 LBX1, Piezo type mechanosensitive ion channel component 2 PIEZO2, Runx family transcription factor 3 RUNX3, and neurotrophin 3 NTF3) investigated in 19 studies were included. LBX1 has confirmed the correlation with the development of idiopathic scoliosis in 10 ethnicities, whereas PIEZO2 has shown a connection with clinical proprioceptive tests in subjects with idiopathic scoliosis. However, curve severity was less likely to be related to the proprioceptive genes. The potential pathology took place at the proprioceptive neurons. Evidence of proprioception-related gene mutations in association with idiopathic scoliosis was established. Nevertheless, the causation between the initiation, progression, and treatment outcomes with proprioceptive defect requires further investigation.
Healthy ageing modifies neuromuscular control of human overground walking. Previous studies found that ageing changes gait biomechanics, but whether there is concurrent ageing-related modulation of ...neuromuscular control remains unclear. We analyzed gait kinematics and electromyographic signals (EMGs; 14 lower-limb and trunk muscles) collected at three speeds during overground walking in 11 healthy young adults (mean age of 23.4 years) and 11 healthy elderlies (67.2 years). Neuromuscular control was characterized by extracting muscle synergies from EMGs and the synergies of both groups were <inline-formula> <tex-math notation="LaTeX">{k} </tex-math></inline-formula>-means-clustered. The synergies of the two groups were grossly similar, but we observed numerous cluster- and muscle-specific differences between the age groups. At the population level, some hip-motion-related synergy clusters were more frequently identified in elderlies while others, more frequent in young adults. Such differences in synergy prevalence between the age groups are consistent with the finding that elderlies had a larger hip flexion range. For the synergies shared between both groups, the elderlies had higher inter-subject variability of the temporal activations than young adults. To further explore what synergy characteristics may be related to this inter-subject variability, we found that the inter-subject variance of temporal activations correlated negatively with the sparseness of the synergies in elderlies but not young adults during slow walking. Overall, our results suggest that as humans age, not only are the muscle synergies for walking fine-tuned in structure, but their temporal activation patterns are also more heterogeneous across individuals, possibly reflecting individual differences in prior sensorimotor experience or ageing-related changes in limb neuro-musculoskeletal properties.
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