RTD50 and PFRoM and PFRoM positively influenced CoP amplitude in ML direction . Moreover, CoP frequency in ML direction significantly increased with lower PFRTD50, DFRTD50, DFRTD200, PFRoM, and DFRoM (p < 0.05). We have demonstrated that ankle strength and RoM were related to single-leg quiet stance postural balance in trained athletes. The ankle RoM showed the greatest influence on CoP variables in ML directions.The aim of this study was to determine the relationship between strength of ankle plantar and dorsal flexors and range of motion (RoM), and body sway variables during single-leg quiet stance, in highly trained athletes. The participants for this study were young athletes from 9 disciplines (n = 655). Center of pressure (CoP) velocity, amplitude, and frequency were measured during single-leg quiet stance. Moreover, athletes were measured for passive ankle plantar flexion (PF) and dorsal flexion (DF) RoM, and for rate of torque development (RTD) in the 0–50 (RTD50) and 0–200 ms time windows (RTD200). Ankle strength and RoM could not predict CoP velocity total, anterior–posterior (AP), and medial–lateral (ML) (p > 0.05). However, PF It is also one the most important skills that protect athletes from injury. This was confirmed in several studies that showed athletes with higher CoP displacements are more prone to injuries in the subsequent training period4. Moreover, larger postural sway was associated with lower incidence of lower limb injuries in prospective study conducted on soccer players5. The study of postural control in larger group of athletes from different sport could provide some insight into the development of specific postural strategies required by a particular sport.Postural balance is the ability to maintain control of the body position above the surface of the support6. Postural sway analysis is performed by processing CoP time series. CoP sway variables are commonly analyzed in a direction specific manner, meaning that the signal is decomposed to AP (anterior–posterior) and ML  directions7. While bipedal quiet stance has been the most common condition used to assess postural sway, according to Riemann, and Schmitz8, unipedal stance has more applications in clinical and sports medicine settings. Moreover, Nevitt et al.9 found that most injurious falls occurred in activities that involved single-leg stance.Several tests for assessing static balance are used routinely in sport and clinical practice, from simple field tests, to instrumented laboratory tests. The most reliable way to evaluate static balance is the recording of center of pressure (CoP) movements during quiet standing, which can be done using a force plate13. Furthermore, high-level athletes exhibit less sway in contrast to low-level athletes14. Previous studies have tried to identify different factors that influence postural sway, such as visual information15, feet position16, motor imagery17, light touch18, age19, and daily life physical activity20. Nevertheless, the influence of other factors remains unknown. Most of the studies that examined the impact of strength and RoM on postural stability were conducted in older adults23. One recent study24 carried out on young adults investigated the relationship between bipedal quiet stance postural sway (CoP length and velocity), ankle RoM, and lower-extremity muscle strength. The results revealed that postural sway was negatively influenced by muscle strength of plantar flexors (PF) and  DF, and ankle PF RoM. Another study showed that low ROM of PF was negative related to overall balance in students aged 20 years25.It was reported that athletes from different sports have reduced sway velocity and sway amplitude compared to non-trained subjects27. There is a strong evidence that elite athletes from different sport disciplines show difference in postural control28. Therefore, there is an urgent call for similar studies with larger sample sizes, using different body sway variables. Additionally, since most of the studies have used bipedal stance for CoP movements, it would be interesting to investigate the relationship between ankle strength and single-leg quiet stance body sway in young highly trained athletes. Moreover, there is a lack of studies that examined the associations between RoM and body sway during single-leg quiet standing. Therefore, the aim of this study was to determine the relationship between ankle strength and RoM and the characteristics of single-leg body sway in highly trained athletes. We hypothesized that a strength, and RoM ankle outcome measures would be significant predictors of AP and ML postural stability during single-leg stance.Understating the mechanisms of postural control in highly trained athletes at different sporting levels is of paramount importance for reducing the risk of injuries and the optimization of the training processThe participants for this study were young athletes from 9 disciplines . The details regarding the sample sizes of individual groups are available in Table max) value during each maximal voluntary contraction trial was quantified as the maximal 1-s mean value of the trial. Next, the rate of torque development (RTD) was calculated as Δ torque/Δ time for 0–50 (RTD50) and 0–200 ms (RTD200) time windows after the onset of the contraction. The onset of torque rise was automatically detected at the instant at which the baseline signal exceeded the 3% of the peak torque. The maximal values from the three repetitions were taken for further analysis.We used an isometric dynamometer  to assess ankle strength . The participant’s shins were tightly secured within the dynamometer, and the feet were placed on a rigid plate mounted above a torque sensor. The sensor built into the dynamometer was embedded in a way that made it function as a torque sensing device. Namely, the force sensor was positioned on a fixed length lever arm in relation to the axis. The axis of the dynamometer was aligned with the medial malleolus. The ankle was in a neutral position (90°), which was achieved by adjusting seat height and seat depth if needed. The feet were tightly fixated against the plates with a strap. The participants were at all times provided with loud verbal encouragement and were instructed to push “as fast and as hard as possible’’ and sustain the maximal effort for ~ 3 s. Three repetitions were performed, with 1 min breaks in between. The signals were processed automatically with arithmetic mean filter (5 ms window) in the manufacturer’s software . The peak torque  with one hand, while stabilizing the shin with the other hand. The second examiner assessed the RoM with a goniometer, aligning the axis with the medial malleolus, with the immovable arm aligned with the shin and the movable arm pointing to the base of the thumb. Three repetitions were performed for each movement, and the mean value was taken for further analyses.29.The body sway was assessed in a single-leg stance without footwear. The participants were instructed to stand as still as possible on the force platform and to look at a fixed point . Participants performed three 30-s repetitions with each leg and 60-s breaks were provided between repetitions. For each repetition, the participants acquired the single-leg position, and the examiner started the acquisition after they had stabilized (1–2 s). Both legs were examined in an alternating order across repetitions, with the starting leg being randomized for each participant. The hip of the opposite  leg was in a neutral position (0°), the thigh was parallel to the standing leg, while the knee was flexed at 90° and was not allowed to touch the standing leg. The knee of the standing leg was in the extended position but not hyperextended (locked). The hands had to be placed on the hips. A piezoelectric force platform  was used to collect the ground reaction force data at a sampling rate of 1000 Hz. The data was automatically filtered  in the MARS Software . The data was further automatically processed in MARS to obtain the outcome measures of interest. For all the outcome variables, the average of the three repetitions was used for further analyses. We considered the mean CoP velocity , CoP amplitude (AP and ML) and CoP frequency (AP and ML). The CoP amplitude was determined as the average CoP sway in AP or ML direction, calculated as the common length of the trajectory of the COP sway only in the given direction, divided by the number of changes of movement direction. The CoP frequency was defined as the frequency of the oscillations of the CoP calculated as the number of peaks in AP or ML direction (i.e. changes in the direction of CoP movement) divided by the measurement time30.Data were analyzed using SPSS  and presented as mean ± standard deviation unless otherwise stated. Normality of data was assessed and verified by Kolmogorov–Smirnov test. An independent T-test estimated the mean differences  between men and women in the outcome variables  and the predictors (PF and DF strength and RoM measures). We used a T-test that is robust for unequal variances with a Satterthwaite approximation in case the Levene’s test yielded unequal variances. A correlation matrix of pairwise Pearson’s correlation coefficient (r) assessed the bivariate linear relationships between outcomes  and predictors , PF and DF MVCt, RTD 0–50 ms and 0–200 ms and RoM measures) prior study hypotheses testing. Pearson’s r values of ± 0.10, ± 0.30, and ± 0.50 demarcated the weak, moderate, and strong relationshipsWe used a hierarchical model building to explore the relationship between CoP velocity , CoP amplitude , and CoP frequency  and DF and PF strength  and DF and PF RoM (Block 2) while controlling for age, gender, and BMI effects (Block 1). The Kolmogorov–Smirnov test and visual inspection of a residual scatter plot confirmed normality and homogeneity of residuals, respectively. Sequential linear regressions analysis was adopted for each outcome. No presentence of multicollinearity was registered in each model according to the variance inflation factor (VIF < 10). We reported standardized coefficients and respecting p values from each model to depict relationships between predictors and each outcome, and to illustrate relative contribution of each predictor to the outcome. The coefficient of determination (R2) adjusted for the number of predictors in the model (adjusted R2) are reported as the measures of goodness of fit of each model. The change in R2 and F from Block 1 to 2 illustrated overall fit of the models for each outcome only in the function of DF and PF strength and RoM measures. The significance was set at p ≤ 0.05.Descriptive data for ankle muscle strength and RoM and CoP variables are presented in Table Results of the correlational analyses between PF and DF strength and RoM and CoP variables are presented in Table Age and gender significantly influenced all body sway variables except CoP frequency AP which was negatively influenced by BMI. Age significantly and negatively influenced all body sway variables, except CoP frequency ML which was positively influenced by age  = 0.52, p = 0.86, R2 = 0.01), AP  = 1.16, p = 0.32, R2 = 0.01), ML  = 0.45, p = 0.91, R2 = 0.01), over and above age and gender alone. Measures of ankle strength and RoM did not also influence CoP amplitude AP  = 1.50, p = 0.14, R2 = 0.02) after accounting for significant age, gender, and BMI effects. However, PFRTD50 and PFRoM and DFRoM positively influenced CoP amplitude ML after controlling for significant age, gender, and BMI effects  = 7.97, p < 0.001, R2 = 0.10).Ankle strength and RoM could not predict CoP velocity total  = 1.11, p = 0.35, R2 = 0.02). CoP frequency ML was nevertheless fitted with ankle strength and RoM measures significantly better than age, gender, and BMI alone  = 11.04, p < 0.001, R2 = 0.14). We found the significant and negative impact of PFRTD50, DFRTD50, DFRTD200 and PFRoM and DFRoM on CoP frequency ML. Results of linear regressions of body sway variables using a hierarchical model building approach are presented in Table CoP frequency AP was not significantly fitted over and above BMI alone (FRTD50 was significantly related to CoP amplitude (ML direction). Moreover, both, PF and DF strength were significant predictors for a CoP frequency in the frontal plane. There were no significant predictors for CoP velocity except for age and gender. Therefore, our hypothesis that ankle strength and RoM would be a predictor of postural stability during quiet stance was partially supported, having in mind that a very low amount of the variance in body sway outcomes was explained.The purpose of this study was to determine if ankle RoM and strength variables were important predictors of body sway parameters during single-leg quiet stance in highly trained athletes from different sports. The most important result was that significant relationships were revealed between RoM measurement and CoP amplitude and frequency. Concerning the contribution of ankle strength in body sway variables, only PF31, injury risk32, but also to an athlete’s performance27. According to Kouzaki et al.23 age-related increases in postural sway are related to decreases in muscle volume. Moreover, research showed that the activity of the ankle PF during quiet standing is far smaller than the maximum34. However, most of the studies have used bilateral quiet standing for measuring postural sway. We have showed in the current study that PF strength (PFRTD50) was related to CoP amplitude in ML direction during single-leg quiet stance. Additionally, PF and DF strength were related to the CoP frequency in ML direction as well. However, it must be stated that only a small proportion of variance was explained (0–12%). The difference in results for ML and AP direction can be explained by the task requirements during upright standing where largest fluctuations occur in AP direction35. Different mechanisms for AP and ML plane postural control during quiet standing36 may contribute to above mentioned association. Accordingly, ML direction is controlled predominantly by frontal plane motion at the hip, whereas AP direction is under ankle control37. Moreover, Pellecchia38 showed that controlling AP direction requires greater attention compared to ML direction when task difficulty is increased in young healthy adults. Based on aforementioned, greater association between PF strength and CoP amplitude in AP direction should be expected, which was not the case in our study. Possible reasons for the difference in the results for AP and ML directions could be attributed to the fact that we used single-leg stance compared to other studies. Single-leg standing requires additional stabilization in ML direction, while several muscles of the ankle act in both frontal and sagittal planes. For instance, tibialis anterior, extensor hallucis longus and brevis as well as hallucis flexors and tibialis posterior are primarily acting as investors, while they also have a significant role in plantar and dorsal flexion. While this explains why we found associations between PF and DF strength with ML CoP, the reason for absence of associations in AP is less clear. We could speculate that under the single-leg conditions, the strength of the muscles becomes relevant only for the ML direction. One the other hand, postural sway in AP direction requires less frequent and less forceful muscle corrections.There is considerable evidence linking balance to the overall athlete’s strength39. The fact that different control strategies are used during bipedal and unipedal standing has important implications for athletic performance and injury prevention, as adaptations to postural balance training have been reported to be highly task-specific40.Moreover, the current results regarding the ML directions corroborates the earlier research which found that control in bipedal standing is accomplished mainly by hip invertors and evertors, while one-leg standing requires fine frontal ankle control41 and later by Kim et al.42 in non-ecological postural conditions. Sawers et al. (2015) observed less muscle co-activation and better muscle output efficiency in elite ballet dancers compared to novice dancers41. Similarly, Kim et al. (2018) found that elite female ice hockey players show lower co-activation of ankle PF and DF compared to non-athletes during unexpected external perturbations42. Slightly larger involvement of PF than DF strength in CoP amplitude during quiet stance was found in our highly trained athletes. Our findings concerning the association of ankle PF strength and CoP amplitude support the statement that static balance may be more related to PF strength than DF strength43.Smaller neuromuscular demands during quiet stance in elite athletes were confirmed by Sawers et al.44 found that a restriction of ankle RoM by external support reduces postural stability in young adults. This was confirmed by Kim and Kim24 who found that out of ankle RoM measures and various lower limb strength measures, ankle PF RoM in young adults showed the greatest association with static balance control ability. On the contrary, one study showed there was no relationship between ankle RoM and postural balance in younger adults43. In the present study, the PFRoM and DFRoM were correlated with CoP amplitude in ML direction and CoP frequency during quiet stance.The available literature on relationships between ankle RoM and static balance is limited in a population of healthy trained athletes. Bennell and Goldie45. There is a greater average decrement of ankle joint RoM in females than males with aging22, which was confirmed in our study where age and gender were significant predictors in almost all body sway components. Additionally, most of the studies that investigated the association of ankle RoM and body sway were conducted on young adults, adults, as well as older adults, with little possibility of comparing our results with other results from similar studies. Nevertheless, the biggest strength of our study is a large sample of highly trained athletes from different sports. The results from the current study showed that body sway during quiet stance is similar in both legs regardless of a sport confirming that highly trained athletes use both limbs effectively in playing and stabilizing the body46. Additionally, the current study showed which control strategy during unipedal standing is used by highly trained athletes.The discrepancy in the results concerning the association of RoM and body sway and the difference between ML and AP direction in the current study may be due to several reasons. The athletes in the current study were highly trained from different individual and team sports. Moreover, some athletes were younger, probably with incomplete postural control system maturation47 stated that foot morphology affects the postural sway in single-leg stance, which was not considered in the present study. Finally, based on a small proportion of the variance that explained body sway during single-leg quiet stance, it remains unclear whether balance and ankle strength and RoM are independent or dependent neuromuscular capacities in healthy young trained athletes. The findings from the current study provide further evidence concerning the relationship between increased ankle strength and RoM and body sway. However, due to the fact that only small amount of the variance in CoP variables was explained, further research are warranted.A few limitations should be mentioned, in particular in view of the nature of testing approach. Although single-leg standing tests are common in obtaining standardized data, it would be desirable for highly trained athletes to assess balance under more complex or unstable conditions. Another important limitation is the fact that participants were highly trained and healthy. Therefore, the results cannot be generalized to injured populations or older adults. Studies in which researchers would investigate similar relations in injured populations, are warranted. Additionally, Hertel et al.In the present study, we demonstrated that postural balance during single-leg stance in young trained athletes is correlated with ankle ROM and muscle strength. Specifically, ankle RoM showed significant relationship with CoP variables in ML direction. Accordingly, decreased ankle RoM can be considered as an important determinant of body sway in trained athletes. The results of the current study could be of benefit to the practitioners seeking to identify postural profile and to make an appropriate adjustment for balance performance enhancement.


This aqueous mixture was injected into 1% (w/v) water solution containing sodium tripolyphosphate to form spherical immobilized beads. The surface of the immobilized beads was reinforced by 0.25% (v/v) glutaraldehyde cross-linking. These beads had enough mechanical strength during BDE-209 degradation to maintain their shape in the system at a stirring rate of 200-rpm, while undergoing continuous 365 nm UVA irradiation. This novel TiO2-Yi-Li immobilized chitosan beads system allowed a successful simultaneous integration of photolysis, photocatalysis and biodegradation to remove BDE-209. The remaining percentage of BDE-209 was 41% after 70 days of degradation using this system. The dominant bacteria in the BDE-209-degrading bacterial mixed culture during remediation were Chitinophaga spp., Methyloversatilis spp., Terrimonas spp. and Pseudomonas spp. These bacteria tolerated the long-term UVA irradiation and high-level free radicals present, while utilizing BDE-209 as their primary carbon resource. This new method has great potential for the treatment of a range of pollutants.A novel chitosan immobilization technique that entraps photocatalyst and microbes was developed and applied to decompose decabromodiphenyl ether (BDE-209) in a clay slurry microcosm. The optimized conditions for immobilization were obtained by mixing 1.2% ( Pseudomonas spp., Terrimonas spp., Sphingomonas spp., Lysinibacillus spp., Bacillus spp. and Stenotrophomonas spp., have the ability to biodegrade PBDEs [Microbial bioremediation is considered to be an effective and environmentally friendly method for treating many emerging contaminants (ECs) present in soil and aquatic systems . Polybrode PBDEs ,7,8. Howde PBDEs ,10. To ide PBDEs ,12.2) has been shown to have a strong ability to accelerate photodegradation of ECs, including BDE-209 (C12Br10O), in aquatic systems when accompanied by UV irradiation [2 nanoparticles, which significantly reduces the effectiveness of the photocatalytic reaction [2 by simple filtration after treatment is challenging due to their very small size; this limits the ability to reuse these particles [2 using organic or inorganic materials, and these have included silica gel, films, membranes, concrete, glass, alginate beads and chitosan beads. The use of an immobilization process before treating the ECs makes it a relatively easy process to recover the TiO2 nanoparticles once treatment is completed [The photocatalyst titanium dioxide  was selected as the immobilization matrix material. The TiO2-nanoparticles (P25) were manufactured by Uni Region Bio-Tech Inc., Taipei, Taiwan. The BDE-209  used in this study had a purity above 99%. All other chemicals, including acetic acid, sodium tripolyphosphate (Na5O3P10), methyl blue (MB), and others, were reagent grade with a purity of >99%. All organic liquids, for example glutaraldehyde, were of HPLC grade with a purity of >99.9%. The Milli-Q water (>18 MΩcm) used in this study was obtained from a Millipore water purification system.High-molecular-weight Chitosan , which is present in surface soils, and to a much lesser extent in subsoils, on UV photolysis and biodegradation. The physical-chemical characteristics of the sorbents are shown in 2-microbes immobilization beads. These two types of novel beads thus ought to be able to utilize PBDEs as a sole carbon source and the bacteria within them should also be capable of growing well under long-term UVA irradiation [The isolations of the indigenous bacterial mixed cultures used in this study were from PBDEs-contaminated river sediment and were carried out by our laboratory was described in a previous study . The abiadiation .2 immobilized chitosan beads is shown in 2-chitosan suspension. The rest of the immobilization procedure was the same as the procedure used for creating the TiO2 immobilized chitosan beads. The whole procedure was carried out under aseptic conditions.The scheme used in this study to create the TiOFirst, 20 mL Yi-Li bacterial mixed culture were aliquoted and centrifuged at 3000 rpm for 5 min to remove the soil from the original culture. The supernatant was then transferred to a new tube and centrifuged at 10,000 rpm for 10 min. The pellet was resuspended in 1 mL 0.85% NaCl and added to each reagent for the designated time period and under the designated conditions as shown in After serial dilution of the samples, 100 μL of each dilution was spread onto: (1) R2A agar for enumeration of soil heterotrophic bacteria; (2) BDE-209-mineral salts basal agar (BDE209-MSA) for the enumeration of BDE-209-biodegrading bacteria. After incubation, the colonies were counted and the bacteria numbers in the original sample were calculated.2 immobilized chitosan beads. 2 immobilized chitosan beads under continuing 365 nm UVA irradiation for 24 h. The optimal proportion of 10% (w/v) TiO2 immobilized chitosan beads was added and were shaken at 100 rpm at room temperature under various experimental conditions.The aqueous MB  degradation experiment was set up in order to evaluate the photocatalytic activity of TiO2-Yi-Li immobilized chitosan beads. Specifically, 100 μL of solution from each step, as showed in The same protocol, as described in w/v) TiO2-Yi-Li immobilized chitosan beads was added to the clay slurry microcosms (data not shown). The clay slurry microcosms were incubated with shaking at 100 rpm at room temperature under various experimental conditions. These were: (1) biodegradation alone by TiO2-Yi-Li bacteria immobilized cells; (2) photodegradation alone by the 365 nm LED UVA irradiation at 2.0–2.4 mW/cm2; (3) both biodegradation and photodegradation; (4) the negative control microcosms were sterilized with the biocide NaN3 . Samples for the experimental analysis were taken from each individual microcosm.BDE-209-contaminated clay were initially prepared at 20 mg/kg, as described in a previous study . Batch b® conductive graphite gel. Next the specimens were pretreated with a sequence of freeze-dried and Au sputtering processes. Following this procedure, the specimens were frozen using a manifold freeze dryer and then are dried at −80 ℃ overnight. Finally, energy dispersive X-ray (EDX) analysis on immobilized cell samples was performed by the field emission-SEM using a EDX spectrometer .A cryogenic scanning electron microscope  was used to carry out the observations of the immobilized cell samples at 5 kV. The beads containing the immobilized cells were initially cut by scalpel and then they were fixed on a specimens-stage using TedPella PELCOA serial process involving ultrasound-assisted extraction, solid-phase extraction, and vacuum concentration was carried out on the clay slurry microcosm samples. After this pretreatment, the samples underwent HPLC analysis to detect and measure BDE-209. The HPLC system was equipped with a UV detector  at 226 nm, an ODS Hypersil C18 column  and was operated at 30 ℃. The operating conditions of the HPLC system were as follows: 25 μL injection sample and 1 mL/min mobile phase 100% acetonitrile. Triplicate analysis of the BDE-209 in each sample was carried out. The retention time of BDE-209 on this HPLC chromatographic system was 8.916 min.−) byproduct concentrations were measured at intervals during debromination as the BDE-209 degradation in a clay slurry microcosm by TiO2-Yi-Li immobilized beads took place. This was carried out using an ion chromatograph  equipped with a conductivity detector. Samples of the supernatant liquid were separated by high-speed centrifugation, filtered through a 0.22-μm nylon filter, and then their Br− concentration was measured immediately. The retention time for Br− by IC chromatography was 8.29 min.Bromide  to count the total number of heterotrophic bacteria able to grow on this medium. Restrictive BDE209-MSA agar was also used to count the bacteria identified in this system. Each sample was diluted 101–1010-fold using sterilized saline solution (KH2PO4 and MgCl2 6H2O) after the sample had been collected; then, 0.2 mL of each dilution was spread on the relevant agar plates and incubated at room temperature for up to 48 h.The bacteria were incubated on R2A agar  and day 56 (D56). DNA samples were extracted using a Soil Genomic DNA Purification Kit . The bacterial communities were then analyzed using the MiSeq, paired-end 300 bp primer set , which aAbsorbance measurements were carried out on a spectrophotometer and degradation of MB at a wavelength of 664 nm was measured.In order to determine the optimal concentrations of chitosan, sodium tripolyphosphate, and glutaraldehyde to be used in the immobilization procedure, preliminary tests were carried out under the conditions shown in 2 immobilized chitosan beads were made using different concentrations of reagents. The total weight and the appearance of the TiO2 immobilized chitosan beads made from 50 mL of chitosan-TiO2 mixed suspension were the two factors used to determine the optimal concentrations of each reagent needed for the immobilization procedure. Previous studies suggested that the concentration of chitosan in the solution should be in the range between 1.2% to 4.5% and that gelling would require the addition of an aqueous solution of tripolyphosphate at a concentration within the range between 1% and 3%; finally, to reinforce the surface of beads, glutaraldehyde at a concentration of 0.25% would be needed in order to obtain regular shaped beads that have good protection against environmental shear forces [2 immobilized chitosan beads and the condition used for this batch were: 1.2% (w/v) chitosan mixed with TiO2 nanoparticles dissolved in 50 mL 1% (v/v) acetic acid and gelling within 1% (w/v) sodium tripolyphosphate. The surface of beads was reinforced by soaking in 0.25% glutaraldehyde (v/v). In total, 12.5 g TiO2 of immobilized chitosan beads were able to be produced, and these had an average diameter of 2 mm.Six batches of TiOr forces ,27,28. B2-Yi-Li immobilized chitosan beads in an aerobic clay slurry microcosm; this is because chitosan, glutaraldehyde and TiO2 have all been reported to have antibacterial ability [The bacteria viability test was set up to confirm that the BDE-209-degrading bacterial mixed culture is able to survive in contact with the various reagents used in immobilization process before degradation of BDE-209 by TiO ability ,29,30. I ability . The res2 and glutaraldehyde. Nonetheless, the Yi-Li bacteria were able to survive all of the chemical reagent steps used in the immobilization procedure and seem to be quite resistant to the level of free radicals released by the TiO2 under continuous 365 nm UVA irradiation. As The number of viable Yi-Li bacteria were found to decrease when they were in contact with chitosan, TiO2-Yi-Li immobilized beads are shown in The bacterial entrapment and releasing ability of the TiO2-chitosan mixed suspension was 1.31 × 108 CFU/mL. Step 2 shows the remaining bacteria after mixing the bacteria with the TiO2-chitosan mixed suspension. Step 3 shows the number of remaining bacteria, 2.96 × 105 CFU/mL, after contact for 30 min with the TiO2-chitosan mixed suspension. The bacteria numbers slightly dropped during Step 2 and Step 3 since both chitosan and TiO2 have an antibacterial effect. At Step 4, there was no bacteria present in the decanted sodium tripolyphosphate solution, which indicates that all of the added bacteria were entrapped within the chitosan immobilized beads. At Steps 5 and 6, no bacterial were detected in the decanted glutaraldehyde and NaCl, which confirms that the bacteria were still immobilized within the chitosan beads without leakage. At Step 7, which was carried out 28 days after beads had been made, the number of bacteria released into aqueous solution was estimated to be 8.9 × 108 CFU/mL, which is more than the initial number of Yi-Li bacteria added during the immobilization process. The bacterial release profile was carried out in an aqueous solution; yet, bacteria entrapped in the beads, once released, can recover and thrive under such conditions, although no nutrients are available in the aqueous solution. Thus, it would seem that the Yi-Li bacteria were able to recover from the immobilization process, divide and finally become released from the chitosan immobilized beads into the outside environment.The purpose of this experiment was to indirectly confirm that the immobilization technique was able to entrap the bacteria within the chitosan beads and then slowly release the bacteria from the immobilized beads into the environment. Step 1 found that the initial bacterial number added to the TiO2 immobilized chitosan beads and the TiO2-Yi-Li immobilized chitosan beads are shown in 2-Yi-Li immobilized chitosan beads is shown in 2 can be observed in The SEM microphotographs of the TiO2-Yi-Li immobilized chitosan beads to remove BDE-209 in a clay slurry microcosm and also to determine the contribution to this process of the Yi-Li bacteria and the TiO2, a clay slurry microcosm containing BDE-209 was set up. The TiO2-Yi-Li immobilized chitosan beads or Yi-Li immobilized chitosan beads were added the slurry systems and UVA irradiation begun; this time point was recorded as Day 0 (D0). The concentration of BDE-209 remaining in the clay slurry on Day 0 (D0), Day 42 (D42) and Day 70 (D70) were measured and are shown in To confirm ability of the TiO2-Yi-Li immobilized chitosan beads had decreased to 13.81 mg/kg on D42 and to 8.22 mg/kg on D70. The remaining ratio of BDE-209 was calculated for this system to be 0.41 after 70 days of degradation. The BDE-209 concentration of the system containing the Yi-Li immobilized chitosan beads was found to have decreased to 14.93 mg/kg on D42 and to 10.69 mg/kg on D70. The remaining ratio of BDE-209 was calculated to be 0.53.The initial concentration of BDE-209 for both systems on D0 were 20 mg/kg. The BDE-209 concentration of the system containing the TiO2-Yi-Li immobilized chitosan beads with UVA irradiation showed a higher BDE-209 degradation ability than adding the beads containing Yi-Li bacteria alone. The TiO2-Yi-Li immobilized chitosan beads with 365 nm UVA irradiation produced bromide concentrations that increased from 0.64 mg/L on D0 to 27.69 mg/L on D70. On the other hand, the Yi-Li immobilized chitosan beads with UVA irradiation produce bromide concentrations that increased from 1.19 mg/L on D0 to 22.95 mg/L on D70.Debromination of BDE-209 has been reported to occur by biodegradation and by photolysis. The amount of bromide released into the clay soil slurry was measured for both systems in order to assess the debromination of BDE-209. The TiO2-Yi-Li immobilized chitosan beads and with Yi-Li immobilized chitosan beads during the biodegradation process are compared in Changes in bacterial populations over time were estimated by plating samples on R2A agar and BDE-209-MSA agar containing BDE-209 as a sole carbon source; samples obtained during the UV irradiation-biodegradation process with TiO5 CFU/g on D0 to a high of 2.88 × 1013 CFU/g on D70. A similar trend was found for the number of bacteria present growing on BDE-209-MSA-agar, which increased from 4 × 105 CFU/g on D0 to 1.56 × 1013 CFU/g on D70. Furthermore, the average number of bacteria present also increased during the UV irradiation-biodegradation process with TiO2-Yi-Li immobilized chitosan beads. The total number of bacteria growth on R2A agar present during the UV irradiation-biodegradation process with TiO2-Yi-Li immobilized chitosan beads increased from 1.45 × 107 CFU/g on D0 to 2.72 × 1012 CFU/g on D70. The number of bacteria present growing on BDE-209-MSB agar increased from 1.08 × 107 CFU/g on D0 to 9.27 × 1010 CFU/g on D70. However, the number of bacteria present showed a decrease to 9.26 × 109 CFU/mL on D42. From this it is inferred that the number of Yi-Li bacteria present was affected by the continuous UV irradiation present in the latter system, although it was able to recover.The average number of bacteria present increased over time during the biodegradation process with Yi-Li immobilized chitosan beads. The total number of bacteria present growing on R2A agar increased from 3.67 × 10Pseudomonas spp. and Acinetobacter spp. for both bead systems. 2-Yi-Li immobilized chitosan beads with UVA group system was explored, the dominant bacteria were now Chitinophaga spp. (50.17%), Methyloversatilis spp. (9.11%), Terrimonas spp. (7.41%) and Pseudomonas spp. (6.96%). This should be compared with the D56 of the Yi-Li immobilized chitosan beads with UVA system, where the dominant bacteria were Chitinophaga spp. (29.33%), Pseudomonas spp. (17.76%), Pedobacter spp. (17.50%), Cephaloticoccus spp. (3.46%) and Isosphaera spp. (3.40%).On D56, when the community structure of the TiO2-Yi-Li immobilized chitosan beads in the present study decreased in the order TiO2-Yi-Li immobilized chitosan beads  > Yi-Li immobilized chitosan beads . Previously, the rates of BDE-209 degradation in a clay slurry system have been ranked for an aerobic novel bioslurry reactor in the order: coupled UV photolysis-biodegradation  > UV photolysis alone  > biodegradation alone  [The biodegradation kinetics of BDE-209 in a clay/water system can be described as first-order. The first-order rate constants (k) for BDE-209 degradation containing TiO, 1/day) . The slo, 1/day) .2-Yi-Li immobilized beads and Yi-Li-immobilized beads. The TiO2-Yi-Li immobilized beads contain, at day 0, more viable CFUs as compared to Yi-Li-immobilized beads (at least two orders of magnitude). However, bacterial number of TiO2-Yi-Li immobilized beads is restricted by both photolysis and photocatalysis after 28 h during BDE-209 degradation. It is inferred that the better degradation performances of BDE-209 by adding TiO2-Yi-Li immobilized beads is measured, considering the synergistic effect of TiO2 particles and the metabolic potential of bacteria entrapped in the beads.Biodegradation is not the only mechanism to remove BDE-209 in a clay/water system between adding TiO2 powders provide a significant level of photocatalytic activity compared to other immobilized cells techniques [2 nanoparticles not enclosed in beads is likely to result in widespread distribution of these nanoparticles into the environment, and this could become a significant secondary contamination problem. Finally, TiO2-Yi-Li immobilized chitosan beads are able to entrap both suspended nano-TiO2 particles and significant numbers of BDE-209 biodegrading bacteria with a higher metabolic activity; both of which can carry out excellent removal of BDE-209 in a clay slurry system. Multiple mechanisms, namely UV photolysis, photocatalysis, and biodegradation, are expected to occur at the same time during the TiO2-Yi-Li immobilized chitosan bead remediation process. The TiO2 immobilized chitosan beads technique would seem to be one of the best practical methods for remediating ECs ex-situ without causing significant environmental contamination.There are some advantages to the use of immobilized bacterial cells for soil bioremediation, biodegradation, and biotransformation of ECs in wastewater treatment plants. First, compared with clay slurries systems utilizing suspended microorganisms, immobilized bacterial beads offer good biocompatibility, good bioavailability, a low cost and ease of preparation. Secondly, the suspended TiOchniques . The use2 immobilized chitosan beads preparation protocol was developed and modified on the basis of several studies [2 particles and microbes together in beads and use these to treat ECs in a clay slurry system, the beads need to be relatively strong in terms of mechanical strength; this is because they must maintain their shape in a stirred clay slurry system. Additionally, the immobilized beads need enough mechanical strength to allow them to be potentially used in aerobic bioslurry reactors for ex-situ bioremediation when future applications are developed [Alginate and chitosan have been shown to have good compatibility when used an immobilization matrix . Since t studies ,27,28. Ieveloped . Thus, c2 immobilized chitosan beads in this study. 2 immobilized chitosan beads retain their photocatalytic activity in the presence of UVA irradiation throughout the experiment.MB was selected as the model organic contaminant to evaluate the degradation performance of the TiO2 immobilized chitosan beads (89.11%) >0.05% TiO2 immobilized chitosan beads (70.02%) >0.01% TiO2 immobilized chitosan beads (19.08%). The pseudo first-order-rate constants were calculated to be: 0.1% TiO2 immobilized chitosan beads  >0.05% TiO2 immobilized chitosan beads  >0.01% TiO2 immobilized chitosan beads . Degradation of MB did not occur under the five control conditions, which are variants 1–5 listed in 2 immobilized chitosan beads over 24 h, and the degradation was brought about by TiO2 photocatalysis. In addition, 2 immobilized chitosan beads before and after MB degradation. Beads have retained their shape and have shown good stability and mechanical strength while in the stirring system. They maintained their shape and diameter throughout the photocatalytic degradation experiment.The percentage of MB degradation (%) under UV irradiation became lower and followed the order: 0.1% TiOPseudomonas spp. and Acinetobacter spp. have been reported to have the ability to degrade BDE-209 and are often found in PBDEs contaminated natural habitats [Methyloversatilis spp. and Terrimonas spp. was significantly higher in the TiO2-Yi-Li immobilized chitosan beads with UVA system compared to the system lacking TiO2. These two bacteria have been reported to be UV-resistant bacteria and have also been shown to have the ability to survive exposure to TiO2 [Methyloversatilis spp. to degrade benzene has been reported, which is suggestive of the ability to break down BDE-209 [Cephaloticoccus spp. have been used to biotransform mycotoxin deoxynivalenol into less toxic metabolites [Chitinophaga spp. were present in significant numbers on the D56 in both groups. This might be attributable to the ability of Chitinophaga spp. to produce extracellular chitinase; this will degrade the chitin that forms the main material of the immobilized beads. Thus, Chitinophaga spp. would seem to be utilizing chitosan as a carbon resource rather than BDE-209, and as a result have become the dominant bacteria by D56 [Isosphaera spp. of aerobic Planctomycetes on the D56 also are chitinolytic microorganisms that are present in wetland soils; they are known to be able to biodegrade the complex heteropolysaccharides present in EPS and cell walls; this seems to be their main ecological function [Many bacteria identified in this study are capable of biodegrading BDE-209, as well as other PBDE congeners and aromatic POPs. Both habitats ,35. The  to TiO2 ,36. In a BDE-209 . Bacteriabolites . Chitinoa by D56 . Isosphafunction .2-UVA irradiation reaction. For example, the percentage of Pseudomonas spp. present can be seen to be a significant difference in both systems, namely 17.76% in the Yi-Li immobilized chitosan beads that lack TiO2 in their UVA system compared to a lower level of 6.69% in TiO2-Yi-Li immobilized chitosan beads, both on D56. On the other hand, some other bacterial species are able to survive and then begin to play important roles in the TiO2-Yi-Li immobilized chitosan beads with UVA system, compared with the Yi-Li immobilized chitosan beads with UVA system, again both on D56. Chitinophaga spp. have been reported to be involved in a combination of non-thermal plasma and biological processes [Pedobacter spp., when exposed to a cold temperature and high UV radiation, have been shown to turn on an important antioxidant system and produce a variety of pigments that belong to the carotenoids group; these are capable of preventing oxidative damage [Photocatalytic reactions create an environment in which some bacterial species do not thrive; this is due to conditions where there are high level of free radicals such as OH· that have been created by the TiOrocesses . Non-thee damage .2 and a BDE-209-degrading bacterial mixed culture are trapped in chitosan beads. It was found that this system is able to effectively remove BDE-209 in a clay slurry system, while at the same time decreasing the risk of secondary contamination of the environment with TiO2. The TiO2-Yi-Li immobilized chitosan beads retained both photocatalytic and biodegradation activity after the various steps needed for immobilization were carried out. Importantly, the Yi-Li microbes added to the beads ability to biodegrade an EC and, furthermore, this mixed culture was able to tolerate long-term UVA irradiation, as well as exposure to the high levels of free radical generated by the TiO2-UV photocatalytic reaction and the UV irradiation itself. In this system, there are three degradation mechanisms in action—microbial bioremediation, photocatalysis and UV degradation—and all of these are likely to have contributed to the breakdown of the high-brominated PBDEs present in the system; this will have produced low-brominated PBDEs congeners. Thus, the TiO2-Yi-Li immobilized chitosan beads are an approach with strong potential for treating ECs contaminated soils. Based on this immobilization procedure, further investigations are needed to increase the mechanical strength of immobilized beads. Such an improvement would mean that the beads could be reused, which would make the treatment of environmental pollutants even more cost effective. Furthermore, the bacteria that are able to tolerate and thrive under the multiple environmental stresses could then be isolated and used to create a new culture that can be added to a new batch of beads. Such a culture, when combined with this new immobilization technique, should have a significantly higher BDE-209 removal efficiency than the Yi-Li culture used here.This study describes the development and characterization of a novel immobilization technique whereby TiO


Trichoplusia ni and two of its pathogens, the DNA virus T. ni nucleopolyhedrovirus (TniSNPV) and the entomopathogenic fungus, Beauveria bassiana to examine how nutrient reduction affected the outcome of mixed pathogen infection. We challenged insects with a low or high effective dose of virus, alone or combined with a single dose of fungus. We manipulated food availability after pathogen challenge by diluting artificial diet with cellulose, a non‐nutritious bulking agent, and examined its impact on host and pathogen fitness. Reducing diet quantity did not alter overall or pathogen‐specific mortality. In all cases, TniSNPV‐induced mortality was negatively affected by fungus challenge. Similarly, B. bassiana‐induced mortality was negatively affected by TniSNPV challenge, but only at the higher virus dose. Dietary dilution mainly affected B. bassiana speed of kill when mixed with a high dose of TniSNPV, with an increase in the duration of fungal infection when cellulose was low (high quantity). One pathogen dominated the production of transmission stages in the cadavers and co‐infection did not affect the yield of either pathogen. There was no evidence that co‐infections were more costly to the survivors of pathogen challenge. In conclusion, dietary dilution did not determine the outcome of mixed pathogen infection, but it had more subtle effects, that differed between the two pathogens and could potentially alter pathogen recycling and host–pathogen dynamics.Infection by pathogens is strongly affected by the diet or condition of the prospective host. Studies that examine the impact of diet have mainly focused on single pathogens; however, co‐infections within a single host are thought to be common. Different pathogen groups might respond differently to resource availability and diverse infections could increase the costs of host defense, meaning the outcome of mixed infections under varying dietary regimes is likely to be hard to predict. We used the generalist cabbage looper,  Little is known about how variation in host resource quantity affects pathogen co‐infections. Here, we show that changes in dietary quantity do not alter mortality in mixed pathogen infections in an insect host. However, a virus and a fungus did respond differently to changes in host nutritional status through subtle changes in duration of infection. As such, changes in host resource quantity could have long‐term effects on pathogen competition and recycling in the host population. We first examined the effect of host condition and co‐infection on host fitness  and then analyzed pathogen speed of kill and the number of transmission stages produced by each pathogen. We exposed the insects to two doses of the virus to examine how the outcome was influenced by the relative effective dose of each pathogen. Both pathogens require host death for horizontal transmission to occur; however, they differ in their host range, infection route and the symptoms caused in the infected host. TniSNPV transmission stages, called occlusion bodies (OBs), need to be ingested to initiate infection, whereas entomopathogenic fungi, such as B. bassiana, initiate infection when the fungal spores germinate on the host cuticle. The symptoms of the two pathogens are very distinct. Virus infection spreads from the mid‐gut via the tracheoles to most organs of the larvae, resulting in a swollen, pale body. The transmission stages are not released until after host death, when the fragile integument breaks open to release millions of newly formed OBs  would increase host mortality as the two pathogens have very different infection pathways and this should increase the cost of fighting the co‐infection and the sublethal costs of survival. We also predicted that reduced host nutrition would result in earlier death and a reduction in the resources available for pathogen replication. In addition, as B. bassiana kills its host more rapidly than TniSNPV in single infections, we also predicted that TniSNPV would be at a disadvantage in mixed infections.In this study, we investigate the effect of diet availability on mixed pathogen infection using a lepidopteran host, the cabbage looper, Bs Cory, . With fu22.1Trichoplusia ni eggs were obtained from Insect Production Services . After hatch, the larvae were reared individually from the neonate stage and maintained at 25°C with a 16L:8D photoperiod on a wheat germ‐based artificial diet, containing a protein to carbohydrate ratio of 1p:1.1c . We then estimated the concentration of transmission stages for both pathogens using an improved Neubauer haemocytometer  at 400× magnification. We counted four independent dilutions for each pathogen and took the average as the final concentration.Our focal pathogen was a species‐specific baculovirus that was initially isolated from an infected 2.2B. bassiana at a single dose, both pathogens together and no pathogens). Before pathogen challenge, each larva was transferred individually into a 12‐well plate. The insects were then exposed to either 100 or 1000 TniSNPV OBs  by placing a 1 μl droplet of virus on a 3 × 2 mm plug of the standard rearing diet. Larvae that had not consumed the diet plug after 24 h were removed from the experiment. Larvae were infected with B. bassiana by placing a 1 μl droplet of fungal suspension containing 3 × 104 spores (previously determined LD50) onto the dorsal abdomen of the larva. Larvae challenged with both pathogens were first placed into the 12‐well plates containing the virus dose and immediately challenged with the fungus as described above. An additional 70 unchallenged control larvae were given 1 μl of distilled water on a 3 × 2 mm diet plug and another 1 μl of distilled water on their dorsal abdomen.A total of 70 newly molted fourth instar larvae were randomly selected for each of the six pathogen treatments  with cellulose (a non‐nutritive bulking agent), while keeping diet quality  the same. The concentration of total digestible protein and carbohydrate was diluted with one of three levels of cellulose: 25%, 35%, or 40%; with 25% representing the amount of cellulose incorporated into the artificial diet of the stock T. ni colony. However, the nutritive macronutrient protein‐to‐carbohydrate ratio was kept at 1:1, close to their original artificial diet ratio. The rest of the diet components, including micronutrients and antimicrobials  (15% of dry ingredients) were kept constant. Dry ingredients were mixed and suspended at a 1:5 ratio in a 1.35% agar solution  and two mixed ) were transferred to individual 1oz SOLO2.4B. bassiana are very distinct. NPV‐infected larvae usually become flaccid and pale and finally lyse releasing millions of OBs. Fungal infection produces rigid, purple‐colored cadavers. To confirm fungal death and collect transmission stages , any cadavers which did not show the signs of viral infection were first surface sterilized, to reduce contamination, by dipping the cadavers in 1% sodium hypochlorite solution for 1 min. then rinsed twice in distilled water. Sterilized cadavers were then placed individually in a humidity chamber (1oz SOLO cup containing a damp cotton wool) and kept at 24°C. All cadavers in humidity chambers were checked daily for sporulation. If no signs of sporulation occurred within 72 h, the cadavers were then smeared and inspected under oil immersion on a light microscope (×1000) for viral OBs or fungal hyphae. Larvae that survived pathogen challenge and successfully pupated were kept in separate individual cups and weighed 3 days after they formed pupae.Individual larvae were kept on the same diet, monitored daily, and maintained at 24°C with a 16L:8D photoperiod until death or pupation occurred. Cause of death was determined visually as fatal infections caused by TniSNPV or 2.5Larvae that died of viral infection were stored at −20°C after being carefully transferred into a 1.5 ml microtube. Only the cadavers that we were able to transfer whole were included in the viral yield analysis. Up to 10 cadavers per treatment were randomly selected, where possible, to estimate the number of OBs or spores produced per cadaver. To estimate the number of OBs, sterilized water was added to make the volume up to 1 ml. Cadavers were then macerated thoroughly with a micropestle for a minute and vortexed to release the OBs . (ii) To explore the impact of co‐infection and diet on each pathogen individually, we then analyzed mortality and speed of kill focusing on insects which died of TniSNPV infection, and finally, (iii) we analyzed B. bassiana induced mortality and speed of kill. All mortality data were analyzed using generalized linear models (GLM) with a binomial distribution and logit link function. For both overall mortality and TniSNPV‐induced mortality, the models included diet quantity (three levels) and virus dose (high or low) as ordinal, and infection treatment as a categorical variable (single or mixed) (Table glht function (with the mcp=“Tukey” specification) from the package multcomp  we first analyzed overall larval mortality and speed of kill  Table . In all d) Table . Where nViral and fungal yield were both analyzed using general linear models. TniSNPV yield (numbers of OBs per insect) was square root transformed to meet the assumption of normality. Diet quantity (three levels) and virus dose  were included as ordinal variables and the infection treatment as categorical (single or mixed) Table . Speed oT. ni development. Only diet (three levels) was included in this first model. We then looked at both pupal weight from the control group and from the larvae that survived pathogen challenge in a second ANOVA, including diet quantity, virus dose  as ordinal and fungus as categorical (Fungus or No fungus) variables  + 1‐pupal weighti) and then log transformed to fit the assumption of normality. Tukey HSD comparisons were performed when significant differences among treatments were detected in the ANOVAs. All analyses were conducted in R‐4.0.1.Finally, we looked at the larvae that survived pathogen challenge by analyzing pupal weight. We first analyzed the pupal weight of the control group only using an ANOVA to examine if dietary dilution alone had an impact on es Table . Pupal w3None of the unchallenged larvae died of pathogen infection; thus, they were not included in the mortality and speed of kill analyses. Interestingly, the outcome of pathogen infection (host death plus the production of transmission stages) in the mixed pathogen treatments resulted in one pathogen dominating the infection and thus cause of death was visually distinct and easy to establish in all cases.3.13.1.1Overall mortality was about 21% higher in the mixed infections  compared to the single virus treatments but was not affected by dietary dilution. Mortality was higher at the high virus dose (77%) compared to mortality in the low virus dose (63%), regardless of the infection treatment Table .3.1.2Dietary dilution had no impact on virus‐induced mortality in single or co‐infections. The combined viral mortality was 66% in the single infections but decreased to 38% when co‐infected with fungus. When only virus‐induced mortality was considered, it was much higher at the higher virus dose (68%) compared to the low dose (35%), regardless of treatment Table .3.1.3χ22 = 27.17, p < .0001, Figure χ42 = 2.21, p = .70; cellulose: χ22 = 2.18, p = .34).Co‐infection with the virus reduced fungal mortality by 67%, but only at the highest virus dose , but only on the diet containing the least amount of cellulose (high quantity) Figure  and only3.2.2B. bassiana.The amount of cellulose in the diet did not affect the speed of kill of TniSNPV, although the significance was borderline Table  with vir3.2.3Beauveria bassiana speed of kill remained constant (around 5.6 days), regardless of diet quantity, when infecting larvae on its own. However, the speed of mixed infections was altered by diet quantity. On low cellulose (25% high quantity) diets, larvae killed by fungus took on average one day longer to die when co‐infected with TniSNPV at the high dose (1000 OBs) compared to the mixed low virus treatment, but on the middle 35% diet the mixed low virus treatment was slower than the fungus alone  = 5.45, p < .001; cellulose: F = 0.78, p = .35; virus dose: F = 4.68, p = .01; Figure 3.33.3.19 OBs and neither the diet nor co‐challenge with the fungus had any impact on virus yield  = 0.44, p = .65; cellulose × sg/mix: F = 1.925, p = .15; virus × sg/mix: F = 0.10, p = .76; cellulose × virus: F = 0.93, p = .40; sg/mix: F = 0.14, p = .71; cellulose: F = 2.16, p = .12). The production of transmission stages was on average 11% higher (1.4–6.9 × 109 OBs) when larvae were challenged with a low dose of TniSNPV compared to a high dose  = 4.93, p = .03). The total number of OBs per cadaver peaked at 7–8 days post‐infection and declined with further increases in time to death  = 0.96, p = .33; (speed kill)2: F = 10.83, p = .001, Figure On average, each virus‐killed cadaver produced 3.3 × 103.3.28 spores and neither co‐infection with virus nor diluting the diet with cellulose affected the number of spores produced by insects killed by B. bassiana  = 0.41, p = .80; cellulose: F = 1.16, p = .32; virus dose: F = 0.83, p = .44). The total number of spores produced on fungal cadavers was not related to speed of kill  = 0.98, p = .33; (speed kill)2: F = 0.07, p = .79).Fungal cadavers produced on average 1.72 × 103.4F = 2.24, p = .12). However, when including the pupal weight from the control group and all the larvae that survived pathogen challenge in the single and mixed infections treatments, diluting the amount of food available reduced pupal weight, but only at the highest dilution level, and this was not influenced by infection treatment or virus dose  = 8.98, p = .0002; cellulose × fungus: F = 0.86, p = .426; cellulose × virus: F = 0.65, p = .631; cellulose × virus × fungus: F = 0.38, p = .82; Figure B. bassiana produced larger pupae than those that were not  = 4.96, p = .027; virus × fungus: F = 1.07, p = .346; virus: F = 1.01, p = .366).The diet treatments alone, in the absence of pathogen infection, had no effect on the pupal weight of the unchallenged (control) larvae  produced heavier pupae, which could be the result of selection for larger larvae. However, NPV challenge did not affect pupal weight, although reduced female pupal mass and fecundity have been recorded in Lepidoptera as a result of surviving virus challenge . However, again, there was no difference in the production of transmission stages, which is not related to B. bassiana time to death, suggesting that the fungus was better at using resources (in competition with the virus) on the more dilute diet. Changes in the duration of infection are likely to impact the speed that secondary cycles are initiated in the wild, affecting the speed of transmission. Baculoviruses only infect the larval stage of their host, but changes in speed of kill will have added importance when pathogens can infect adult hosts where longevity could affect reproduction, both of which could have important consequences at the population level.While host mortality was not affected by changes in diet quantity, infection duration was. Focusing on pathogen‐specific speed of kill as this is what determines secondary transmission, TniSNPV took longer to kill its host in the co‐infection treatments, regardless of the host diet. This suggests that either the virus access to necessary resources was limited due to competition with the fungus, or that the virus is slowing down the use of the host resource to keep the host alive to acquire the necessary resources for its own development . However, in this experiment, larvae only had access to food for a specific period of time (4–5 h for the low food treatment), so the hosts were intermittently starved, which resulted in different sized larvae. Baculovirus yield is often strongly correlated with speed of kill, as more OBs can be produced if the host stays alive longer and grows larger  within the host, but did significantly affect the size of the parasite, with larger parasites found in the treatments with the highest amount of food  pathogen infections in terms of host mortality or pathogen yield, although there were more subtle effects on speed of kill, which could affect the rate of pathogen recycling in the host population. This suggests that in circumstances where the hosts can compensate for a more dilute or reduced diet by eating more or for longer, the quantity of diet available has little effect on disease resistance in insects, although an extended development period is likely to have other costs in the field. It also suggests that different pathogen groups are affected differently by changes dietary dilution; in this case, the fungus appeared to be more sensitive, potentially due to its high rate of exploitation of host resources. However, these effects were overridden by the relative effective dose of each pathogen, illustrating the subtle interplay between diet and disease. It is also interesting to note that diet reduction has also been shown to have transgenerational impacts on disease resistance ; data curation (lead); formal analysis (lead); funding acquisition ; investigation (lead); methodology ; project administration ; resources ; software ; validation ; visualization (lead); writing – original draft (lead); writing – review and editing . Jenny S. Cory: Conceptualization ; data curation (supporting); formal analysis (supporting); funding acquisition ; investigation (supporting); methodology ; project administration ; resources ; supervision (lead); validation ; writing – original draft (supporting); writing – review and editing .


This retrospective cohort study described changes in all-cause healthcare resource utilization (HCRU) and associated costs in dementia patients newly diagnosed with psychosis. Dementia and incident psychosis were identified using diagnostic and pharmacy claims using a Medicare 20% random sample dataset. All-cause HCRU and unweighted and weighted (by person-years of follow-up) HCRU-associated costs were evaluated in the year prior to and the 4 years following diagnosis of psychosis. In 49,509 dementia patients with psychosis, physician visits per patient per year increased from a mean of 26.7 (standard deviation (SD) 20.0) prior to psychosis to 38.4 (SD 41.9) post-psychosis diagnosis. The number of inpatient stay claims increased from 1.0 (SD 1.4) to 1.7 (SD 5.8). Mean unweighted costs for inpatient stays and home healthcare/hospice during 2008–2016 were USD 9989 and USD 3279 prior to a diagnosis of psychosis but increased to USD 25,982 and USD 9901 , respectively, in the year after a psychosis diagnosis. This pattern of a sharp increase in mean costs was also observed in costs adjusted to 2015 USD, and in both unweighted and weighted total and psychosis-related costs. These results indicate the importance of identifying newly diagnosed psychosis in dementia patients as well as the pressing need for management strategies and treatments that can reduce HCRU and costs. The natural course of dementia involves progressive neurodegeneration, a process accompanied by new and worsening symptoms, heightened caregiver burden, and increased utilization of medical and long-term care (LTC) resources . NeuropsCertain types of NPS are more likely than others to require HCRU. For example, dementia-related hallucinations and delusions may generate more acute and urgent needs, such as outpatient or emergency department (ED) visits, inpatient stays/hospitalizations, or admission to LTC facilities . In contA number of studies have assessed HCRU and costs associated with dementia and dementia-related NPS ,4,17,18,This retrospective cohort study used the 20% Medicare random sample of beneficiaries enrolled at any time between 1 January 2008 and 31 December 2016. Methods used here to identify patients with dementia and dementia-related psychosis were described in a previous report analyzing the risk of death and use of long-term care associated with dementia-related psychosis in the same patient population . All datMedicare beneficiaries ≥ 40 years old with Medicare fee-for-service coverage  for at least 1 year before the dementia index date met criteria for dementia-related psychosis. Patients with dementia were identified based on 1 of the following sets of criteria: ≥2 dementia diagnosis codes , Clinical Modifications codes; Patients with newly diagnosed psychosis were identified from patients identified with dementia. Patients with incident dementia-related psychosis were identified based on 1 of the following criteria: (1) ≥2 diagnosis codes for psychosis  after thBaseline demographics and comorbid conditions were identified for patients with dementia only and incident dementia-related psychosis. Comorbid conditions were defined using qualifying diagnosis codes from ≥1 inpatient, skilled nursing facility (SNF), or home healthcare/hospice (HH/HS) claim or ≥2 outpatient ED/observation stays, physician visits, or durable medical equipment (DME) claims on different days during the baseline period. Comorbid conditions were identified according to the Charlson Comorbidity Index .We report two major outcomes: HCRU and costs. HCRU is assessed in the form of claims generated for services, as described more fully below. For Medicare costs, we assessed Medicare allowable costs, which include costs paid by Medicare as well as by patients. Allowable costs, which can be considered as representing the perspective of both the entitlement program payer (Medicare) and the patient, best represent total costs. The HCRU and Medicare allowable cost outcomes are reported as both all-cause and cause-specific for dementia-related psychosis, the latter of which represents the specific economic burden on healthcare systems and payers associated with the emergence of dementia-related psychosis. All-cause and psychosis-related HCRU and associated costs were assessed for the 12 months before the dementia-related psychosis index date (baseline period) and during the follow-up period. The follow-up period was categorized into yearly increments. The follow-up period began on the index date and continued until death, loss of Medicare Parts A, B, or D eligibility, or end of the study period (31 December 2016), whichever came first. Data for the first 4 years of post-index follow-up are reported here. No discount rates were used to interpret changes in costs during follow-up.For both all-cause and psychosis-related analyses, HCRU was evaluated for the following: inpatient stays , ED/observation stays, nonemergency unscheduled outpatient visits, SNF, HH/HS, physician visits, prescriptions for DME, and prescription drug fills. The mean number of claims per patient per year and annualized costs were evaluated overall and for each setting. All-cause Medicare-covered prescription drug claims and costs were estimated using Medicare Part D claims. Prescription drug claims were counted according to the actual number of claims. Initially, costs were annualized and evaluated as unweighted means, which are commonly reported. Due to person-years of follow-up time varying by patient , we accounted for variation of follow-up time using weighted means  when determining annualized allowable costs. Both unweighted and weighted costs were adjusted for inflation, expressed as 2015 USD, and measured according to the Medicare allowable costs. LTC stays were identified from a Centers for Medicare and Medicaid Services linkage database with data on LTC Minimum Data Set and Medicare claims. LTC-associated costs were estimated by calculating the length of LTC stay (in days) multiplied by 2015 room rates, using an average of semiprivate and private rates . PatientFor psychosis-related HCRU and cost, claims with psychosis diagnosis codes or prescription drug claims with antipsychotic drugs were examined. Any identified psychosis-related HCRU and costs in the pre-index period refer to those associated with the first psychosis diagnosis code or prescription drug fill for psychosis treatment before the psychosis diagnosis was confirmed, which determined the psychosis index date. Psychosis-related LTC costs were not calculated/reported due to unavailability.HCRU and cost results were calculated using descriptive statistics using SAS version 9.4 . Annualized HCRU was calculated using the total number of claims divided by the total follow-up time (in months) multiplied by 12. The HCRU associated costs were evaluated as unweighted and weighted means. During 2008–2016, 206,899 patients with dementia only and 49,509 patients with both dementia and incident dementia-related psychosis met all inclusion criteria and were included in the analysis . BaselinFor all settings, the unweighted mean annualized number of all-cause HCRU claims per patient per year increased from the year before dementia-related psychosis diagnosis (baseline period) to the years after diagnosis (follow-up period; Unweighted and weighted mean all-cause HCRU-associated costs adjusted to 2015 USD also showed a substantial increase in the first year post index . At all Unweighted and weighted mean all-cause LTC costs, which were calculated separately from Medicare costs, also had the greatest increase from pre-index in the year following the start of dementia-related psychosis  but thenPatterns for psychosis-related HCRU and costs over time were similar to all-cause HCRU and costs, with increases in number of claims  and in bAs with mean all-cause allowable costs, in most settings, the weighted and unweighted mean psychosis-related costs in 2015 USD increased substantially from baseline and were highest during year 1, then decreased during subsequent years to near baseline levels . UnweighIn this large-scale analysis of the Medicare beneficiaries, we found compelling increases in mean HCRU and associated costs in the year following the appearance of newly diagnosed psychosis in patients with dementia. This descriptive analysis revealed an increased economic burden across all the different setting types researched in this study, including inpatient, outpatient, SNF, HH/HS, physician visits, prescription fills, and use of LTC. In the year following a new presentation of psychosis, the mean annualized per patient per year all-cause Medicare and LTC costs in 2015 USD for dementia-related psychosis patients increased by about USD 40,000, reaching nearly USD 90,000 during the year after the psychosis diagnosis. Costs driven by inpatient stays increased from approximately USD 10,000 to USD 26,000 in the post-index year, suggesting that the initial manifestation of psychosis symptoms for patients with dementia is associated with disruptive and costly hospitalizations. Further, HH/HS costs increased from approximately USD 3000 to USD 10,000 in the first year post index and remained more than USD 5000 higher than baseline for at least 4 years post index. Increases in costs associated with HH/HS and prescription drug fills remained elevated for at least 4 years post index, suggesting that the development of psychosis may trigger a new trajectory for patients with dementia that is associated with persistent increased healthcare needs. The greatest proportional increases in psychosis-related costs were for inpatient stays, SNF, and prescription drug costs, with annualized per patient costs of approximately USD 2900, USD 1900, and USD 800, respectively, in the first year following psychosis diagnosis. While psychosis-related HCRU and costs accounted for only a portion of all-cause HCRU and costs in our analysis, it is possible that not all psychosis-related costs are adequately captured by analyzing claims data, particularly if the treating physician identifies dementia rather than the psychotic symptoms associated with dementia on the claim ,14, treaThe highest Medicare costs were observed during this first year following a new psychosis diagnosis; however, LTC costs continued to increase over time. This latter finding would be expected, as the risk of entering an LTC facility increases as the time since a dementia-related psychosis diagnosis increases ,22. The The increase in all-cause claims and weighted and unweighted costs immediately following the index date might indicate that a diagnosis of dementia-related psychosis is often not made until symptoms become severe enough to warrant specific medical attention. Although dementia-related psychosis can be diagnosed at all stages of dementia , the diaThough beyond the scope of the current analysis, future studies could examine how costs associated with dementia-related psychosis are related to symptom severity. Our findings are consistent with existing reports of increased costs associated with a dementia diagnosis and with the presence or worsening of NPS in patients with dementia ,5,12,17.Our study has several important limitations. Results may not generalize to individuals outside of the United States. An assessment of claims data cannot account for indirect and nonmedical costs, which are also known to be high in patients with dementia-related NPS . While tHCRU and costs for patients with dementia increase in the year after a new diagnosis of psychosis. The increase is observed both in unweighted and weighted mean cost per patient per year analyses. Utilization of acute care was a key driver of increased HCRU and costs immediately following diagnosis, highlighting the importance of appropriate treatment and prompt symptom management in newly diagnosed dementia patients with psychosis. Our data suggest that psychosis is associated with a high cost burden overall for patients with dementia, suggesting an unmet need for timely evaluation and management of dementia-related psychosis, and safe and effective treatments for these patients.


Animal viruses are parasites of animal cells that have characteristics such as heredity and replication. Viruses can be divided into non-enveloped and enveloped viruses if a lipid bilayer membrane surrounds them or not. All the membrane proteins of enveloped viruses that function in attachment to target cells or membrane fusion are modified by glycosylation. Glycosylation is one of the most common post-translational modifications of proteins and plays an important role in many biological behaviors, such as protein folding and stabilization, virus attachment to target cell receptors and inhibition of antibody neutralization. Glycans of the host receptors can also regulate the attachment of the viruses and then influence the virus entry. With the development of glycosylation research technology, the research and development of novel virus vaccines and antiviral drugs based on glycan have received increasing attention. Here, we review the effects of host glycans and viral proteins on biological behaviors of viruses, and the opportunities for prevention and treatment of viral infectious diseases. Animal viruses are parasites of animal cells that have characteristics such as heredity and replication, and are mainly composed of DNA or RNA, proteins and in some, a lipid membrane with glycoproteins . CommonlN-glycosylation and O-glycosylation (N-glycosylation means that N-acetylglucosamine (GlcNAc) in an oligosaccharide binds covalently to the polypeptide chain by an N-glycoside linkage with the amide nitrogen of an asparagine residue in the sequence Asn-X-Ser/Thr (X is any amino acid other than proline). The main type of O-glycosylation is the mucin-type O-glycosylation, which means that N-acetylgalactosamine  bonds covalently to the oxygen atom of the hydroxyl group of a serine or threonine residues replacing the hydrogen in the hydroxyl group to form an O-ligand glycoprotein by O-glycoside linkage. Other types of O-ligand subclasses also exist in animal cells, such as O-mannose glycosylation (O-Man), O-fucosylation (O-Fuc), O-galactose  and O-linked β-N-acetylglucosamine (O-GlcNAc) glycans  of the Ebola virus (EBOV) increased GP-mediated virus entry efficiency  is an enveloped virus, and its envelope contains of gp120 surface protein and gp41 transmembrane protein. Moreover, gp120 is one of the most highly glycosylated proteins in nature. It accounts for approximately 50% of the total mass . These ger cells . Similarmutation , 29. In ficiency .Hemagglutinin (HA) and neuraminidase (NA) are the surface glycoproteins of influenza A virus. Influenza virus attaches to the surface of a host cell when its HA protein interacts with the terminal sialic acid (SA) of the host cell surface glycoproteins or glycolipids. On the other hand, NA can cleave SA residues from glycoproteins of the enveloped virus itself and enhance infectivity by preventing aggregation of virus particles . NA may N-glycans added to a protein, they have three terminal glucose residues. These residues will be removed sequentially, with α -glucosidase I (αGI) removing the outermost glucose residue and α-glucosidase II (αGII) removing the next two residues produce the immature GlcMan9GlcNAc2 N-glycans  on the cell surface. Also, gC contains a mucin-like domain (MLD) located near the GAG binding site, which may affect the binding activity between the virus and GAG. HSV-1 mutants that lack these MLDs in gC and found that compared with natural HSV-1, the binding affinity of virions to the cell was reduced and the release ability of mutant virus particles from the surface of infected cells was also reduced . SimilarMoreover, some viruses have even evolved glycosidases to promote virus release . The mosN-glycosylation sites of proteins are added or deleted, these alterations can have an appreciable impact on the survival and transmissibility of a virus , but two of the N-glycan mutants (N230Q and N295Q) show increased infectivity and transmission efficiency  against that site and providing a convenient way for viruses to infect host cells and to promote immune escape. There are two main mechanisms by which viruses can escape the nAbs response.332 in gp120 after HIV infection and also nAbs that target this site were detected in the sera from two people who had responded to an HIV vaccine (a recombinant glycoprotein 120 vaccine), suggesting that HIV antigenic sites are blocked by glycans, resulting in most people failing to produce broadly nAbs  are non-segmented, negative-stranded RNA viruses that belong to the genus  protein . GP is the virus . Similar in mice . Further in mice .N-glycosylation of amino acids at either 154 or 156 increase neuro-invasiveness in mice, avian virulence, and vector competence  (N-acetylneuraminic acid (Neu5Ac), probably to resist the malaria parasite that was able to use Neu5Gc to enter the human body at that time. After completing this evolution, making some diseases seem more particularly specific to humans, such as typhoid, cholera, mumps, pertussis, asthma, and coronavirus diseases (COVID-19)  . When SAOVID-19) , 83.via different glycosidic linkages . Usually, SA exists as a bound sugar at the terminal positions of glycans via various cell surface receptors such as nectin-1 or nectin-2. Finally, the attached virus begins to enter the cells   . This fiExperimental vaccines against HSV-1 target particular viral glycoproteins. HSV envelope gD is expressed on the surface of the virus and induces a nAbs response. The largest current clinical trial of HSV subunit vaccines has found an inhibitory effect on HSV-1, but no effect against HSV-2 . A diffeN- and O-linked glycans  may enhance immunogenicity , and glycosylation of at least one Asn of tetherin is necessary and sufficient for the inhibition of HIV-1 release , Scientific Research Foundation of Liaoning Provincial Education Department (507124), and Liaoning Provincial Program for Top Discipline of Basic Medical Sciences.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


This study aimed to provide practical implications for South Korean corporations seeking to enter the Chinese market. It explored the influences of brand image and favorability toward citizens in a product’s country of origin (FCPCO) on consumers’ product evaluation and repurchase intention, in addition to examining the moderating effects of procedural switching costs , financial switching costs (benefit loss costs and monetary loss costs), and relational switching costs  on the aforementioned influences. Although previous studies have established the relationships between some of the aforementioned variables, further research is required to determine the moderating effects of switching costs in various dimensions. Studies on the relationships of a product’s country of origin with product evaluation and repurchase intention have rarely explored FCPCO. Through a questionnaire survey, this study obtained effective data from 302 respondents. Constituted of an exploratory research design, this study adopted PLS-SEM method for empirical analysis. IPMA analysis results indicated that brand image had a stronger influence on product evaluation than FCPCO did and that FCPCO had a stronger influence on repurchase intention than brand image did. Overall, the performance of FCPCO was higher than that of brand image. Moreover, economic risk costs and brand relationship loss costs positively moderated the relationship between brand image and product evaluation; monetary loss costs and brand relationship loss costs negatively moderated the relationship between FCPCO and product evaluation. These study results could help corporations gain competitive edge. Economic globalization, which epitomizes the advance of human civilization, is an inevitable outcome of economic growth at the global scale. The Regional Comprehensive Economic Partnership, which came into effect on November 15, 2020, is a critical step toward an open global economy and the stabilization of the global economy. With the continual expansion of geographical boundaries in the global economy and the formation and reformation of trade blocs, the association and interdependence between different regions have strengthened substantially. Through the formation of strategic alliances and the acquisition of foreign direct investment, business operations can be upgraded to a global scale, which contributes to the diversification of products in the international market. Investigating the evaluation and repurchase intention of foreign products is crucial in a society facing substantial growth in international commerce. Moreover, a widely held belief is that retaining an old customer is more economic than acquiring a new one . Market Typically, consumers’ decision-making process for a purchase comprises the following phases: problem introduction, information search, appraisal of alternatives, decision-making, and post purchase behavior . ProductWhen purchasing a new product, consumers consider their experience with existing products, the attractiveness of alternatives, and the cost of replacing existing products . SwitchiThis study adopted the classification system proposed by Brand image can be regarded as the image created in consumers’ minds by brand associations , or it cRepurchase intention refers to customers’ intention of purchasing a product or service that they have previously used. It can be regarded as customers’ psychological commitment to a product or service . In the H1: Brand image has a positive effect on product evaluation.H2: Brand image has a positive effect on repurchase intention.Increased international commerce has resulted in the exposure of numerous consumers to foreign goods with unfamiliar origin . BecauseInformation on a product’s country of origin has a considerable influence on consumers’ product evaluation, preference, selection, and purchase intention . The couH3: FCPCO has a positive effect on product evaluation.H4: FCPCO has a positive effect on repurchase intention.The concept of switching costs was first proposed by Procedural switching costs refer to switching costs that require the investment of time and efforts. Four types of procedural switching costs exist as, economic risk costs, evaluation costs, learning costs, and set-up costs . SpecifiFinancial switching costs, which comprise benefit loss costs and monetary loss costs, are quantified losses in financial resources . BenefitRelational switching costs refer to the mental or psychological readjustment required to adapt to the loss of a relationship or identity . TherefoResearchers have not reached a consensus on the moderating effects of switching costs. Some researchers have reported that switching costs exert a positive moderating effect on the relationship between satisfaction and loyalty , whereasH5: Switching costs moderate the relationship between brand image and product evaluation.H5-1: Procedural switching costs  moderate the relationship between brand image and product evaluation.H5-2: Financial switching costs (benefit loss costs and monetary loss costs) moderate the relationship between brand image and product evaluation.H5-3: Relational switching costs  moderate the relationship between brand image and product evaluation.H6: Switching costs moderate the relationship between brand image and repurchase intention.H6-1: Procedural switching costs  moderate the relationship between brand image and repurchase intention.H6-2: Financial switching costs (benefit loss costs and monetary loss costs) moderate the relationship between brand image and repurchase intention.H6-3: Relational switching costs  moderate the relationship between brand image and repurchase intention.H7: Switching costs moderate the relationship between FCPCO and product evaluation.H7-1: Procedural switching costs  moderate the relationship between FCPCO and product evaluation.H7-2: Financial switching costs (benefit loss costs and monetary loss costs) moderate the relationship between FCPCO and product evaluation.H7-3: Relational switching costs  moderate the relationship between FCPCO and product evaluation.H8: Switching costs moderate the relationship between FCPCO and repurchase intention.H8-1: Procedural switching costs  moderate the relationship between FCPCO and repurchase intention.H8-2: Financial switching costs (benefit loss costs and monetary loss costs) moderate the relationship between FCPCO and repurchase intention.H8-3: Relational switching costs  moderate the relationship between FCPCO and repurchase intention via telegraphic transfer) to increase their willingness and credibility. Besides, repeated filling in of the questionnaire by the same participant was prevented through filtration of repeat emails. In addition, invalid questionnaires obviously filled in at random or with many missing values were eliminated to improve the quality of survey data. As to content validity, a research model was designed in this study based on relevant dimensions used in previous literatures. The questions in the questionnaire were developed based on literatures and pre-validated scales. Moreover, the questionnaire was carefully verified and modified by many experts in the field of marketing, so that the content validity of the questionnaire was verified appropriately. The questionnaire was administered between September 13 and October 18, 2020. A total of 328 copies of the questionnaire were distributed, and 302 copies valid questionnaires were retrieved. A questionnaire was designed based on the above research hypotheses, with 20 participants with experience in using Korean products and services invited to complete the prediction. Then, ambiguous contents and those that might be subject to misunderstanding were modified, enabling participants to fully understand the content and improving the quality of the questionnaire. After completing the first draft of the questionnaire, a pilot test was carried out at a university in Beijing to ensure that participants would not misunderstand the questionnaire, in which 100 valid samples were collected. Based on the reliability coefficient criteria recommended by In this study, the partial least squares (PLS) method was used to test the stability of the developed model and verify the proposed hypotheses. Analyses were conducted with the PLS algorithm and bootstrapping method by using the SmartPLS 3.0 software package. The PLS algorithm was used in this study for three reasons. First, this study did not have sufficient theoretical support. Second, the use of the PLS algorithm was due to the lack of a classic theoretical model in this study, which was more oriented toward a theoretical exploration. Third, the developed model contained a large number of constructs .As presented in The convergent validity and discriminant validity were used to test the construct validity. The results of Harman’s single factor analysis indicated that the first factor explained 48.89% of the total variance ; thus, H1 was supported. Brand image positively and significantly affected repurchase intention ; thus, H2 was supported. FCPCO positively and significantly affected product evaluation ; thus, H3 was supported. FCPCO positively and significantly affected repurchase intention ; thus, H4 was supported. The ry power . Thus, bectively . Thus, belevance . ProductLS paths . The bas = 0.36 . A GoF vp < 0.05); monetary loss costs exerted a negative moderating effect on the relationship between FCPCO and product evaluation (p < 0.05); brand relationship loss costs exerted a positive moderating effect on the relationship between brand image and product evaluation (p < 0.001); and brand relationship loss costs exerted a negative moderating effect on the relationship between FCPCO and product evaluation (p < 0.001). Thus, H5-1, H5-3, H7-2, and H7-3 were partially supported.By multiplying the moderating variables with corresponding indicators of predictor variables, interaction terms were created to test the moderating effects of switching costs. Subsequently, a model with moderating variables was compared with a model without moderating variables . The resThis study developed and tested a novel theoretical framework for the moderating effects of switching costs. The developed framework provides international suppliers with new insights regarding marketing strategies. In particular, the findings of this study are of critical importance to South Korean corporations that have already entered or have plans to enter the Chinese market in that these findings can help them manage their relationship with customers. This study found that FCPCO and brand image positively affected product evaluation, which is in agreement with the finding of This study makes the following academic and practical contributions to the fields of international commerce and marketing. First, to the best of our knowledge, the present study is the first to conduct in-depth research on FCPCO. This study expands the understanding on how FCPCO affects product evaluation and repurchase intention. Second, this study conducted a detailed examination into the multidimensional nature of switching costs and their moderating effects. In contrast to previous studies that mostly treated switching costs as a one-dimensional construct, the current study provides insights on the moderating effects of various types of switching costs. Finally, by delineating the moderating effects of switching costs on brand image, FCPCO, and product evaluation, the present study broadened the understanding of the moderating effects of switching costs, fills a gap in the literature.This study has certain limitations that can be improved. First, the scope of this study was limited to South Korea’s commerce with China. Future studies should expand their scope to include other countries. Second, the current study was not based on a specific product or service type. Future studies are advised to investigate the moderating effects of switching costs in different industries, such as the cosmetic industry, mobile device industry, Internet service providing industry, banking industry, and hospitality industry. Third, this study relied on cross-sectional data. Future studies can consider using longitudinal data to conduct a more comprehensive analysis of how the moderating effects of switching costs vary with time. Fourth, the moderating effects of certain types of switching costs were found to be nonsignificant in the present study. Future studies can combine these switching costs with other factors to perform a more thorough investigation. Switching costs are complicated, and additional research is required on their moderating effects. Such research would provide additional insights regarding consumers’ switching costs, thereby facilitating sustainable corporate development.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.Ethical review and approval were not required for the study on human participants in accordance with the local legislation and institutional requirements. The patients/participants provided their written informed consent to participate in this study.YS and RA conceived and designed the study. YS organized the database, performed the statistical analysis, and wrote the manuscript. RA helped with the references. All authors contributed to manuscript revision, read, and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.