The P3a response is thought to reflect involuntary orienting to an unexpected stimulus and has been connected with set-shifting and inhibition in some studies. In our exploratory study, we investigated if the amplitude and the latency of the P3a response were associated with the performance in a modified flanker task measuring inhibition and set-shifting in 10-year-old children (N = 42). Children participated in electroencephalography (EEG) measurement with an auditory multifeature paradigm including standard, deviating, and novel sounds. In addition, they performed a separate flanker task requiring inhibition and set-shifting skills.The P3a latencies for deviant sounds were associated with the reaction time reflecting inhibition: the shorter the response latencies were, the faster the reaction time was. The P3a latencies for novel sounds were not linked to the reaction times reflecting either inhibition or set-shifting. In addition, the magnitude of the P3a response was not associated with the performance in the flanker task.Our results suggest that P3a response latency and reaction speed reflecting inhibitory skills are based on shared neural mechanism. Thus, the present study brings new insight to the field investigating the associations between behavior and its neural indices. The P3a response of the event-related potentials (ERPs) has been proposed to directly index an epistemic (uncertainty-reducing) stage of attention allocation , and it Inhibition and set-shifting skills are functions that are categorized under the umbrella term of executive functions (EF), a set of higher order cognitive processes that enable and regulate goal-oriented actions and are thus crucial for acting in a meaningful way in life. There is no clear consensus about the exact subfunctions that are included in the concept of EF, but according to an influential model by Miyake et al. , executiInhibition refers to an ability to inhibit an automatic, learned, or dominant reaction . This abSet-shifting (SS) refers to an ability to adapt one’s thinking and actions to changing situations or rules. It can be defined as a part of or overlapping with the wider concept of cognitive flexibility that is needed in real-life situations, such as when problem-solving requires a new perspective or a situation demands application of a different mindset . Set-shiExecutive functions mature throughout the childhood –37 and tAuditory P3a response is a fronto-centrally maximal positive component elicited by infrequent, unpredictable stimuli in a stream of repeating sounds and peaking between 200 and 400 ms from the stimulus onset . It origThe unpredictable stimuli eliciting P3a may either be “deviants”, deviating from standard stimulus in some sound feature, such as frequency or intensity, or highly salient “novels”, sounds not sharing any resemblance with standard stimulus. In his review paper, Polich  proposedEven infants and toddlers show a positive component resembling the adult-like P3a –82. TherThe latency of the P3a response appears to be longer in children than in adults , althougThe P3a response has been connected with set-shifting and inhibition in some studies focusing on adults , 13, 14,Even though P3a response is also thought to be connected with attentional allocation, a lot less seems to be known about its associations with behavioral measures of executive functions. Polich et al.  investigOur cross-sectional study focused on associations between the P3a responses and inhibition and set-shifting skills in 10-year-old children. To investigate our hypotheses, we conducted measurements with forty-two 10-year-old children. As our P3a study paradigm, we used well-established multi-feature paradigm , 111. ItDuring childhood maturation, the P3a amplitudes seem to have two parallel trajectories depending on the auditory paradigms: it has been found to increase for small deviants from the standard stimulus and decrease for novel sounds, while reaction times in inhibition and set-shifting paradigms become faster , 110–112To investigate our hypotheses, we conducted linear mixed-model analyses, in which the P3a amplitudes and latencies for deviants  and novel sounds acted as dependent variables and were predicted by reaction times reflecting inhibition and set-shifting. The children’s language and special needs education statuses were also included in the model as predictors, as it was deemed possible that they modulate P3a responses.Table The reaction times reflecting inhibition and set-shifting did not correlate p = 0.772). Neither did the mean amplitude and latency of the P3a response correlate, as determined separately for each deviant and novel sound p = 0.108–0.852). Figure 08–0.852.. NeitherFigure F = 1.290, p = 0.264; F = 0.197, p = 0.660, respectively]. Furthermore, neither the RTINH nor RTSS had a main effect on the P3a amplitudes . This indicates that reaction times reflecting inhibition or set-shifting were not connected to the magnitude of averaged P3a amplitude for deviant stimuli. No significant interaction was found between the children’s language and special needs education status (p = 0.682).According to linear mixed model, children’s language or special needs education status did not have a main effect on the P3a amplitudes for deviant stimuli . The reaction time for inhibition had a significant main effect on the P3a latency for deviants , whereas the reaction time for set-shifting had no such effect . Estimated marginal means evaluating the direction of the association between the P3a latency and RTINH showed that the first and third quartiles of RTINH (Q1 = 14 ms and Q2 = 81 ms) corresponded with P3a latencies of 296 ms and 307 ms. This indicates shorter response latency for children showing faster reaction times related to inhibitory skills. No significant interaction was found between the children’s language and special needs education status (p = 0.115).The children’s language or special needs education status did not have a main effect on the P3a latencies for deviant stimuli . Instead, the special needs education status did have a main effect on both P3a amplitudes and latencies . There was no significant main effect of RTINH or RTSS on the P3a amplitude for novel stimulus . Similarly, no significant main effect of neither RTINH nor RTSS on the latency of the novel P3a was found . No significant interaction was found between the children’s language and special needs education status for either amplitude or latency p = 0.831, p = 0.624, respectively).Conducted linear mixed models revealed no significant main effect of children’s language status on P3a amplitudes or latencies for novel stimuli , it appears that the set-shifting cost is also present in the trials in which no switch happens but the participant is prepared for the set-shifting in the task. Thus, RTSS reflecting set-shifting was calculated by subtracting the mean RTs of the second block  from the mean RTs over all trials in the third block . See Table In the present study, we aimed to resolve the task-impurity problem by using differences between reaction times in the analyses. The measured reaction times for congruent trials in Block 1 (no inhibition task) differ significantly from the RTs for congruent trials in Block 2 .This suggests that the inhibitory control is in use when participants are monitoring the screen in Block 2, both in congruent and incongruent trials. Thus, RTAs the hit rate for the responses was very high , we did not use the number of accurate/inaccurate responses in the analyses. Only the reaction times for correct responses were included in the analyses. See Table https://version.helsinki.fi/hipercog/ctap; . After this, noisy electrodes [average 3.1 (SD 1.8) electrodes] were detected in CTAP by using channel-wise statistics from the FASTER toolbox [A portable EEG equipment  was used in the measurements. The EEG was recorded with 32 Ag–AgCl scalp electrodes postitioned according to the international 10–20 system by using ActiCap . The EEG data were registered with sample rate of 500 Hz. Recording reference was Fpz or FCz depending on the size of the used cap. Out of the 32 active electrodes of the cap, two were placed on the mastoid bones and one below the left eye. The recorded data were processed with CTAP software . H toolbox ; as desc toolbox , and repTo follow the analysis path of the previous papers using the multifeature paradigm , 111, thThe developing P3a responses of children do not reach positive polarity but may show only a notch reaching towards positivity—at least in paradigms with fast stimulation rate see e.g. , 84, 111INH, RTSS, children’s language status (native/non-native) and special needs education status acted as independent predictors. Participants were treated as random factors with random intercept. Alpha level was set at ɑ = 0.05.Linear mixed-model analyses with restricted maximum likelihood were conducted for amplitudes and latencies for deviants  and novel sounds. Bayesian information criteria was used to define model fit. In all models, RT


Alpinia katsumata Hayata (Zingiberaceae), has been demonstrated to possess the activity of anti-breast cancer. Cytochrome P450 enzymes (CYP450s) plays vital roles in the biotransformation of various drugs.Alpinetin, the major active constitutes of To assess the effect of alpinetin on the activity of CYP450s and estimate the inhibition characteristics.The activity of CYP450s was evaluated in pooled human liver microsomes with corresponding substrates and marker reactions. The effect of alpinetin was compared with blank control (negative control) and corresponding inhibitors (positive control). The dose-dependent and time-dependent experiments were conducted in the presence of 0, 2.5, 5, 10, 25, 50, and 100 μM alpinetin and incubated for 0, 5, 10, 15, and 30 min.50 values of 8.23 μM (CYP3A4), 12.64 μM (CYP2C9), and 10.97 μM (CYP2E1), respectively. The inhibition of CYP3A4 was fitted with the non-competitive model with a Ki value of 4.09 μM and was time-dependent with KI and Kinact values of 4.67 min and 0.041 μM−1, respectively. While CYP2C9 and 2E1 were inhibited by alpinetin competitively with Ki values of 6.42 (CYP2C9) and 5.40 μM (CYP2E1), respectively, in a time-independent manner.Alpinetin suppressed CYP3A4, 2C9, and 2E1 activity. All the inhibitions were significantly influenced by alpinetin contration with the ICin vitro inhibitory effect of alpineticn on CYP3A, 2C9, and 2E1 implied the potential interaction of alpinetin or its origin herbs with the drugs metabolised by those CYP450s, which needs further in vivo validation.The  Alpinia katsumata Hayata (Zingiberaceae) seeds have been commonly used in the treatment of inflammation and gastric disorders -methyl-cinnamate, an extraction of A. katsumata, were revealed to suppress pre-osteoblasts growth, migration, and differentiation  are a superfamily that partakes in the biotransformation of various xenobiotics, such as drugs and toxins  was added for the termination of the reactions. All reagents were of at least analytical reagent grade obtained from Sigma Aldrich (USA). All incubations were performed in triplicate and the concentrations of metabolites were analysed with HPLC.The pooled human liver microsomes (HLMs) were obtained from BD Biosciences Discovery Labware. The HLMs were incubated with specific substrates of corresponding CYP450 isoenzymes under the reaction conditions in 50.The effect of alpinetin on the activity of CYP1A2, 2A6, 3A4, 2C8, 2C9, 2C19, 2D6, and 2E1 was first evaluated with a concentration of 100 μM. The isoenzymes that were inhibited by alpinetin were further incubated with 0, 2.5, 5, 10, 25, 50, and 100 μM alpinetin to obtain the values of ICKi. The inhibition model was evaluated according to the following equations: v = (VmaxS)/[Km(1 + I/Ki) + S] for the competitive inhibition and v = (VmaxS)/[(Km + S(1 + I/KiKI)] for the non-competitive inhibition. The I is the concentration of the compound, Ki is the inhibition constant, S is the concentration of the substrate, and Km is the substrate concentration at half the maximum velocity (Vmax) of the reaction.Meanwhile, the kinetic studies were conducted in the presence of various substrate concentrations to obtain the values of Km, while a higher concentration of approximate to 4-fold Km was used in the evaluation of the values of KI and Kinact.The time-dependent inhibition assay was conducted with an incubation time of 0, 5, 10, 15, and 30 min after a 30 min pre-incubation with 1 mg/mL HLMs in the presence of NADPH-generating system at 37 °C. The concentration of corresponding substrates was close to the value of t-test or one-way ANOVA followed by the Turkey post hoc test with SPSS 20.0.All data were presented as mean ± SD and analysed by the Student’s p < 0.01, p < 0.05, p < 0.01, 50 were obtained as 8.23 μM (CYP3A4) 12.64 μM (CYP2C9), and 10.97 μM (CYP2E1), respectively  was revealed to inhibit the activity of CYP2C8, 2C19, and 3A4 in a dose-dependent manner  on CYP3A4 led to its interaction with conventional CYP3A4 substrates (Sabarathinam et al. Herein, the inhibition of CYP3A4, 2C9, and 2E1 by alpinetin was observed, which was displayed in a concentration-dependent manner with various ICin vivo effect of alpinetin on CYP450s activity might be affected by the metabolites of alpinetin. A previous study has investigated the metabolites of alpinetin in rat plasma, urine, bile, and faeces, and identified a series of compounds with various functional groups, which was considered as the other potential mechanism underlying the inhibition of CYP3A4, 2C9, and 2E1 by alpinetin. On the other hand, the obtained in vitro findings directly evidenced the suppression of CYP3A4, 2C9, and 2E1 by alpinetin. However, the specific drug-drug interaction between alpinetin or its original source and their co-administrated drugs needs further in vivo validations.Previously, the role of genetic polymorphism in drug–drug interactions has been reported as a key factor that might affect the catalytic activity of CYP450 and therefore induce adverse drug–drug interaction (Bozina et al. in vitro. The administrated dose and incubation time were demonstrated to be two key factors that affected the degree of inhibition.Taken together, alpinetin dramatically inhibited CYP3A4, 2C9, and 2E1


In this review, we summarized the generation of IgE+ PCs, discussed the prosurvival factors in the microenvironment, and reviewed the unique IgE-BCR signaling, which may bring insights into understanding the survival mechanisms of IgE+ LLPCs.Persistent allergies affect the quality of life of patients and increase economic burdens. Many clinical observations indicate the presence of IgE Allergic diseases are a global health problem and a significant burden to society and patients. Over the past two decades, the prevalence of various allergic diseases has increased , 2. Alle+ LLPCs may account for persistent IgE secretion , discussed the prosurvival factors in the microenvironment, and reviewed the IgE-BCR downstream pathways which uniquely regulate IgE+ PCs longevity.Long-lived plasma cells (LLPCs) are critical for maintaining adaptive humoral immunity after recovery from infection or vaccination. However, LLPCs also generate pathogenic antibodies, thus causing a variety of diseases or problems, such as systemic lupus erythematosus, allograft rejection, and persistent allergy , 9. IgE ecretion . To clar+ LLPCs were inducible in allergic mouse models. Mice injected intraperitoneally with a single dose of OVA with or without aluminum hydroxide (HA) had a persistent titer of OVA-specific IgE in serum and long-lived IgE-secreting cells in the bone marrow (BM) and spleen. Moreover, administration with X-irradiation, a lethal dose of x-rays sufficient to deplete B memory cells rather than LLPCs, only partially affected IgE levels and IgE+ secreting cell counts  could survive ex vivo for at least 32 days, a lifespan of LLPCs in the human intestine, indicating the existence of LLPCs in nasal polyps  are more likely to produce high-affinity IgE. In contrast, low-affinity IgE derives from IgE+ cells undergoing direct class switching (IgM → IgE)  and affinity maturation, after interacting with antigen-dependent T cells. GC B cells further differentiate into PCs under the interaction with follicular dendritic cells and T follicular (Tfh) cells , 24. Tfhneration . IgE+ ceM → IgE) –30. In hM → IgE) , 31.+ GC B cells and IgE+ PCs in mice immunized with OVA + PEP1 or infected with N. brasiliensis. They found that Sγ1 remnants presented in a proportion of IgE+ PCs but not in IgE+ GC B cells, indicating that IgG1+ cells could be the precursors of IgE+ PCs besides IgE+ GC B cells  or sequentially (IgD → IgA/IgG → IgE) in the nasal mucosa  of asthmatic patients was detected , 45. Thesurvival . IL-5 plsurvival . The expferation . Multiplferation . Collect+ cells are rare, and IgE+ B cells are likely to differentiate into SLPCs and undergo apoptosis  is the lowest of all the Ig subclasses in non-atopic persons . In addipoptosis . Thus, tnditions . Besidess  has an additional extra-membrane proximal domain (EMPD) region between Cε4 and the transmembrane M1 domain. EMPD contains 52 amino acid residues and exists in some primate species, including humans (S). In the human B cell line, the amount of mIgEL was much lower than mIgES on the cell surface due to EMPD. EMPD could act as an autonomous endoplasmic reticulum (ER) retention domain and might restrict the transport of mIgEL from ER to the cellular membrane  has two isoforms sharing the same mRNA precursor but alternative splicing sites. The long form of mIgE  mutation and cultured with IL-4 and anti-CD40 antibodies show an impaired formation of IgE+ PCs (+ PC differentiation and apoptosis in an antigen-independent way. In a human B cell line, stimulating mIgES of DG75 B cells with anti-IgE antibodies also leads to apoptosis (L are controversial. Haniuda et al. found that mIgEL could stimulate activation-induced cell apoptosis in vitro but is less efficient than mIgES (in vitro apply to IgE+ PC cells in vivo is unclear.Compared to wild-type mice, mice with IgE-BCR mutation show a reduction of IgEmulation . In vitrIgE+ PCs . AnotherIgE+ PCs . Thus, Ipoptosis . Studiesan mIgES . In contan mIgES . Howevervia activating PLC-γ2 (Like other BCRs, IgE-BCR is non-covalently associated with CD79a and CD79b signaling devices. However, IgE-BCR could activate the downstream signaling autonomously . CD79a ag PLC-γ2 . In contg PLC-γ2 –62. The g PLC-γ2 .In vitro, the CD19 pathway was proven to play a crucial role in IgE+ SLPCs differentiation but not apoptosis. Further, researchers immunized mice with the TD Ag NP-CGG in alum to clarify the function of CD19 in vivo. CD19+/− mice had attenuated IgE+ PC differentiation but a long-lasting serum IgE titer. BLNK-Jnk/p38 rather than Erk pathway donated to IgE+ SLPCs differentiation and apoptosis. Immunized BLNK−/− mice also had a long-lasting serum IgE titer and generation of IgE+ LLPCs (via activating BLNK-Jnk/p38 and CD19-PI3K-Akt-IRF4 pathways (+ and IgG1+ PCs. This result is consistent with studies that rapamycin could cause a reduction in serum IgE and IgG1 in mice induced by allergens (+ PCs and IgE+ GC-like B cells elevates due to the autonomous activation of Syk/BLNK (+ PCs caused mitochondrial apoptosis mediated by BIM (+ PCs differentiation rather than apoptosis (Haniuda et al.  transducE+ LLPCs . Therefopathways . The PI3llergens –65. The Syk/BLNK , 65. Enhpoptosis .S isoform lacking EMPD could also activate downstream signaling of BCR without stimulation, there should be other alternative regions for spontaneous activation. The domains CH1-CH4 of IgE are sufficient to active Syk and BLNK in chimeric BCR without EMPD (+ PCs, and memory IgE responses in mice (+ PCs differentiation and apoptosis (+ PCs maintenance through calcium signaling pathways. In addition, ITT promotes IgE surface expression, which may facilitate the activation of IgE-BCR (Both ectodomain and cytoplastic tail contribute to IgE-BCR signaling. Chimeric BCR containing transmembrane cytoplastic tail of IgG1 and ectodomains of IgE could induce PC differentiation and apoptosis; however, the ectodomains of IgG1 and transmembrane cytoplastic tail of IgE could not, implying that the ectodomains of IgE-BCR contributed to downstream signaling spontaneous activation . Moreoveout EMPD . More re in mice . As mentpoptosis , 65. ITT IgE-BCR .S. To clarify the distinct functions of mIgEL and mIgES, Vanshylla et al. (L and mIgES expressing cells. They found that mIgEL-expressing cells had much weaker signaling of PI3K/Akt, MAPK, and calcium signaling pathways. Moreover, compared with full-length IgE-BCR, IgE-BCR with EMPD deletion significantly promotes murine B cell apoptosis (S signaling promotes SLPCs differentiation and apoptosis; impaired mIgES function contributes to LLPC generation and long-lasting serum IgE titer (L could compete and attenuate the mIgES pro-apoptosis effect remained to be elucidated. If that is the case, the ratio mIgEL/mIgES on PCs surface may be implicated in the survival of PCs.The molecular mechanisms based on mouse models or mouse cell lines are associated with mIgEa et al.  generatepoptosis . As discgE titer . Whether+ LLPCs for persistent allergies, but the characteristics of IgE+ LLPCs are poorly studied, especially in humans. IgE+ LLPCs could be induced in the allergic mouse model, but only indirect evidence supports the presence of IgE+ LLPCs in allergic patients. IgE+ LLPCs mainly reside in BM and are lesser in the spleen and mucous. The prosurvival factors in the BM have been extensively studied, but a few focus on the mucosal microenvironment where IgE+ LLPCs exist. In non-atopy conditions, IgE+ B cells showed the propensity to differentiate into SLPCs due to the autonomous activation of IgE-BCR signaling. It is interesting to investigate the change of these signaling pathways in subjects with persistent allergies. In addition, mIgEL and mIgES deliver altered signaling, which may play distinct roles in IgE+ PCs survival. Applying mutant mice expressing mIgEL isoform helps to explore the unique role of mIgEL in allergic conditions.Clinical observations indicate the responsibility of IgE


The maximal pullout forces from the same screw positions in unicortical fixation modalities were all significantly lower, decreases that ranged from 32.7 to 74%, than those in bicortical fixation modalities. Our study using porcine vertebrae showed that screws in the middle or posterior position of the lateral vertebral body had a higher pullout performance than those in the anterior position. Posteriorly positioned lateral vertebral screws with unicortical fixation provided better stability than anteriorly positioned screws with bicortical fixation.Although an anterior approach with anterior lateral screw fixation has been developed for stabilizing the thoracolumbar spine clinically, screw loosening still occurs. In this novel in vitro study, we attempted to elucidate the optimal screw position in the lateral lumbar vertebra and the effect of bicortical fixation. A total of 72 fresh-frozen lumbar vertebrae from L1–6 were harvested from 12 mature pigs and randomly assigned to two modalities: bicortical fixation (n = 36) and unicortical fixation (n = 36). Six groups of screw positions in the lateral vertebral body in each modality were designated as central-anterior, central-middle, central-posterior, lower-anterior, lower-middle, and lower- posterior; 6 specimens were used in each group. The correlations between screw fixation modalities, screw positions and axial pullout strength were analyzed. An appropriate screw trajectory and insertional depth were confirmed using axial and sagittal X-ray imaging prior to pullout testing. In both bicortical and unicortical fixation modalities, the screw pullout force was significantly higher in the posterior or middle position than in the anterior position ( However, for large vertebral defects, the anterior thoraco-abdominal approach with spinal instrumentation anterior to the lesion has been proven to be more effective in immediate postoperative stability, deformity correction and neurological safety while eradicating the spinal lesion11. In recent years, oblique lumbar interbody fusion (OLIF) with supplemental anterior lateral screws-rod fixation has gained popularity in the context of degenerative lumbar disease13. This approach offers the advantage of direct visualization of the anterior and middle column pathology and allows anterior large support to be placed without irritating the nerve and avoids posterior pedicle screws fixation10. Several anterior fixation systems have been developed for stabilizing the thoracolumbar spine clinically, but screw loosening still occurs17. The anterior plating system has been widely compared with other biomechanical stabilization systems by using functional spinal units of human or swine cadavers23, but the importance of screw position on the lateral side of the vertebra and the effect of bicortical fixation have never been evaluated. The bone in the region between the screw thread crests is damaged and subsequently lowered the instrumented construct stability when a screw is pullout24. The individual screw axial pullout test has been proved to be correlated with construct stability26. In this novel in vitro experimental study, we compared the pullout strength of screws in six different positions relative to the lateral side of normal-density porcine vertebrae: central-anterior (C-a), central-middle (C-m), central- posterior (C-p), lower-anterior (L-a), lower-middle (L-m), and lower-posterior (L-p). Meanwhile, the present study is the first to conduct a biomechanical comparison between bicortical and unicortical fixation of anterior lateral vertebral screws.Posterior pedicle screw fixation for spinal fusion surgery is a useful procedure for the treatment of spinal disorders, including fracture, degeneration, idiopathic scoliosis, infection or metastatic spinal tumorsBefore image analysis, no malposition or fractures in the implanted specimens were grossly observed Figs. , 2. The An appropriate screw trajectory and insertional depth were also confirmed using axial and sagittal X-ray imaging prior to pullout testing in the bicortical Fig.  and unicIn the bicortical fixation modalities, the C-p, C-m, C-a, L-p, L-m, and L-a groups had mean pullout force values of 3683.43 ± 1093.33 N, 2718.89 ± 802.31 N, 1434.16 ± 592.68 N, 3081.72 ± 682.25 N, 2692.62 ± 606.14 N, and 1261.61 ± 484.58 N, respectively 35. Both large vessels are in the anterior region, which eliminates the concern of vascular injury from bicortical fixation in the middle or posterior position. Interestingly, unicortical purchased screws in the posterior and middle position showed significant higher pullout force than bicortical purchased screws in anterior position , which indicated that screws in a middle or posterior position with bicortical fixation reached better stability.There were some limitations in our study. First, our data represent only pullout force in a context of normal bone density; osteoporotic bone density should be compared for further clinical applications. Second, porcine models cannot totally represent human vertebrae, and physiological cyclic loading or bending force could be applied for long-term evaluation. Third, only one screw size was examined; further investigations with various sizes and screw geometries might be necessary.Our study using porcine vertebrae showed that screws in the middle or posterior position of the lateral vertebral body had a higher pullout performance than those in the anterior position. Posteriorly positioned lateral vertebral screws with unicortical fixation provided better stability than anteriorly positioned screws with bicortical fixation.This study was approved by the committee of Chang Gung Memorial Hospital of Taiwan (CRRPG3M0121). All specimens were purchased from commercial meat market  and were exempted from filing an Institutional Animal Care and Use Committees (IACUCs) protocol for the use of dead animal-derived bone.42. All the specimens were separated into individual vertebrae after being stripped of the surrounding soft tissue. The specimens were conditionally allocated into six groups from L1 to L6 to avoid size-induced selection bias.A total of 72 fresh frozen L1–6 single vertebrae were used in the study. Specimens were harvested from 12 mature pigs (weight: 80–90 kg). All animals were healthy before harvesting and had never been exposed to any drugs or procedures that could have affected bone densityAll specimens were stored at − 20 °C until the day of testing and thawed for 24 h before implantation. The six groups of screw insertional positions were designated central-anterior (C-a), central-middle (C-m), central-posterior (C-p), lower-anterior (L-a), lower-middle (L-m), and lower-posterior (L-p). The central position was defined as the middle part of the superior and inferior endplates in the lateral plane of vertebra, while the lower position was the lower third between the superior and inferior endplates Fig. A. The anAxial and sagittal views were examined via X-ray for all specimens prior to the pullout test to confirm an appropriate screw trajectory and insertion depth. All screws were implanted into the vertebrae by an experienced surgeon, and the insertional depth in the unicortical fixation modality was controlled such that there was at least 2 mm from the screw tip to the opposite cortex; in the bicortical fixation modality, at least 2 thread widths penetrated out of the opposite cortex. The vertebrae were thoroughly examined to rule out any malposition or fractures caused by screw insertion.44. Data collection was set at 1 sample/0.05 mm. Failure was defined as the maximum force or the force peak prior to a decrease in force associated with increasing displacement. After the pullout test was completed, the specimen and the screws were closely examined for signs of fracture and damage and any findings were carefully recorded.Each of the 72 specimens was potted in metal boxes using specific epoxy resins . The specimens were carefully potted into acrylic resin in a cubic shape to fit the square clamp below the universal joint, and the screw head outside the vertebrae was covered with pottery clay to avoid the contact between resin and screw. The prepared specimens were mounted onto a material testing machine  to conduct axial pullout tests with the screws. The screw head was fixed to a cylindrical rod with an inner thread that matched the outer thread of the screw head via a universal adaptor Fig. . The uniStatistical software  was used to analyze the pullout force of all the specimens. All of the measurements were collected for 72 vertebrae and the results were expressed as the mean ± standard deviation (SD). The Kruskal–Wallis test was used to determine significance differences between median values of subgroups. p values were 2-sided and adjusted by Bonferroni correction when multiple comparisons were performed. Mann–Whitney U tests was used to compare unicortical purchased screws in the posterior and middle position to bicortical purchased screws in anterior position. Differences were considered statistically significant at p < 0.05.


Arctic sea ice extent continues to decline at an unprecedented rate that is commonly underestimated by climate projection models. This disagreement may imply biases in the representation of processes that bring heat to the sea ice in these models. Here we reveal interactions between ocean-ice heat fluxes, sea ice cover, and upper-ocean eddies that constitute a positive feedback missing in climate models. Using an eddy-resolving global ocean model, we demonstrate that ocean-ice heat fluxes are predominantly induced by localized and intermittent ocean eddies, filaments, and internal waves that episodically advect warm subsurface waters into the mixed layer where they are in direct contact with sea ice. The energetics of near-surface eddies interacting with sea ice are modulated by frictional dissipation in ice-ocean boundary layers, being dominant under consolidated winter ice but substantially reduced under low-concentrated weak sea ice in marginal ice zones. Our results indicate that Arctic sea ice loss will reduce upper-ocean dissipation, which will produce more energetic eddies and amplified ocean-ice heat exchange. We thus emphasize the need for sea ice-aware parameterizations of eddy-induced ice-ocean heat fluxes in climate models. Arctic sea ice extent continues to decline at an unprecedented rate that climate projection models commonly underestimate. In this study, authors reveal a positive feedback between ocean-ice heat fluxes, sea ice cover, and upper-ocean vortices that is missing in coarse-resolution climate models. The spatial extent and seasonal migration of marginal ice zones (MIZs)—highly fluctuating areas of relatively weak and low-concentrated sea ice next to the open ocean—are also increasing5. On monthly to seasonal timescales, sea ice predictions from climate models show a range of accuracies,7, with sensitive dependence on the initialization month8. However, the largest sea ice variability and prediction errors occur within MIZs9. On interannual and longer timescales, climate projection models have widespread estimates of sea ice extent3, which may imply biases in processes that transport heat towards the ice. Various feedbacks associated with longwave radiation, surface albedo, lapse rate, water vapor, clouds11 as well as internal climate variability are among the proposed candidate processes that need to be improved in climate models. This study is focused on exploring mesoscale and submesoscale sea ice-ocean interactions that are not typically resolved in climate models but might substantially affect ocean-ice heat fluxes (OHFs).Global warming has led to a dramatic decrease in Arctic summer sea ice extent and thickness, resulting in weaker and more mobile sea ice with stronger fracturing and more lead openings12, which remain uncertain, especially at meso- and smaller scales. Indeed, a network of ice-mass buoy observations has demonstrated that in areas of dramatic Arctic sea ice loss, the relative importance of ocean heat fluxes on sea ice melt increased over the past few decades14. Lateral stirring that arises from under-ice Arctic Ocean eddies is far from quiescent, with energetic eddies commonly observed by in situ instruments18. In MIZs, eddies are visually evident in sea ice concentration patterns20, while sharp meltwater fronts and strong vertical isopycnal excursions are observed by ocean gliders21 and Ice-Tethered Profilers22. Ice mass Buoys have measured sporadic O(100 W m−2) enhancement in heat fluxes associated with the passage of warm-core eddies in MIZs22. Sea-ice evolution also depends on the presence of surface and internal gravity waves that can lead to vertical mixing and affect the floe-size distribution26. Process studies suggest that ocean fronts and eddies can be formed due to winds28 as well as spatially-heterogeneous buoyancy fluxes from sea ice growth/melt, and are responsible for advecting warm ocean waters laterally and vertically towards the sea ice, accelerating its melt30.Sea-ice growth/melt is highly sensitive to ocean heat fluxes31, climate models do not resolve ice-ocean interactions at scales comparable to the Rossby deformation radius, typically O(10 km) in the deep Arctic Ocean32. The presence of sea ice, however, can affect ocean turbulence in several critical ways. First, sea ice can frictionally dissipate internal gravity waves33 and macro-scale ocean turbulence36, affecting mixed layer energetics and the strength of eddy-heat transport. Second, since sea ice can only absorb heat from the ocean that is typically stored beneath the mixed layer, vertical motions in the ocean could lead to an asymmetric response: upwelling is associated with enhanced heat transport whereas downwelling leads to negligible heat transport38. Thus, the presence of energetic internal gravity waves, vertical mixing, or eddy-induced upwelling would tend to enhance ice-ocean heat fluxes. At the same time, the transmission of stress from fine-scale oceanic features (order of 10 km) to the sea ice cover could cause the sporadic plastic failure of the ice and lead to a reduction in the areal sea ice coverage, which is not captured in low-resolution ocean-ice models39. Yet, model parameterizations of mesoscale40, submesoscale41, and boundary layer42 turbulence have been developed for ice-free oceans and hence cannot represent the impacts of changing sea-ice concentration on ice-ocean heat fluxes.With rare exceptions43. Since the model is not a data assimilation product, it represents one plausible scenario of sea ice development under prescribed atmospheric forcing and hence the regional circulation and sea ice patterns may differ from observations. Nonetheless, the model presents a unique dynamical tool for the exploration of ice-ocean interactions and feedbacks that are not resolved in state-of-art climate models.Here, we quantify mechanical and thermodynamical ice-ocean interactions following a seasonal cycle in a global ocean model at a high resolution of <1 km in the Arctic Ocean (see methods). This unique model includes tides and internal gravity waves, resolves mesoscale eddies in deep Arctic basins, and permits the development of submesoscale flows, thus allowing us to quantify critical sea ice-ocean interactions that are not currently accounted for by climate models. This high-resolution ocean model, simulated for slightly longer than a year, is forced with reanalysis of atmospheric conditions for the year 2012, which corresponds to the record-low sea ice extent45 and Supplementary Figure Satellite observations of sea ice in MIZs reveal that sea ice clusters in eddies and filaments  for mesoscale eddies observed under the sea ice48. When the winds are negligibly low, the ice and mixed layer ocean velocities will also be closely linked, following the scaling. However, since winds have a much larger spatial extent than ocean eddies, the atmospheric stress curl provides only a minor contribution compared to the curl of the ice-ocean stresses. Hence the vorticity of free-drifting sea ice in MIZs is expected to be correlated with ocean vorticity, even in the presence of winds. In MIZs, the scaling relationship in  rheology used in our numerical simulations, the sea ice strength P is an exponential function of its concentration C* = 20 strongly affecting the value of the critical concentration ccr  over an eddy in the Arctic MIZ have been previously reported22. The conditional distribution of OHFs is thus positively biased over anticyclones and has a much wider tail corresponding to anomalously strong heat fluxes  spectral slope from k−4 in the summer to k−1 in the winter at ~30-km wavelength  and Rossby numbers O(0.1)  , being distinct from submesoscale flows in temperate oceans that are characterized by a k−2 spectrum and Rossby numbers of O(1)54. Unlike the mesoscale, the submesoscale vorticity variance does not vary seasonally . Hence,The seasonal dynamics discussed above imply a positive feedback between sea ice cover, upper-ocean eddies, and ice-ocean heat fluxes: as the sea ice melts, the key dissipation mechanism for upper-ocean variability diminishes and allows for energetic eddies to develop, bringing subsurface heat towards the sea ice, further accelerating its melt. The same feedback occurs in winter, but friction now suppresses upper-ocean eddies and leads to enhanced sea-ice growth. Assessing the strength of this feedback is challenging. The physical components of the feedback must be isolated from a myriad of other unrelated processes, and the model output only spans a single year. Nevertheless, the Arctic Ocean’s spatial heterogeneity can be used advantageously to demonstrate strong connections between the key processes in the eddy-heat flux feedback.ct/c) is significantly correlated with the fractional rate of change in sea-ice volume per unit area (ch)t/(ch), with a regression coefficient of 0.6 ± 0.2 t = −OHF + o.t., where L = 333.7 × 103 J kg−1 is the latent heat of fusion and ρi = 900 kg m−3 is the characteristic density of sea ice; here o.t. represents other terms associated with atmosphere-ice and radiative heat fluxes.Regional variability in ocean-ice evolution, at seasonal times scales, is analyzed by dividing the Arctic Ocean into non-overlapping sub-domains, with 500 km sides, and diagnosing the linear sensitivity of key upper-ocean and sea-ice characteristics using monthly-mean time series averaged over the sub-domains. During the winter-spring transition, upper-ocean EKE  exhibits strong sensitivity to changes in sea ice concentration; EKE becomes three times stronger following the disappearance of sea ice  × 10−3 m2 s−2. Second, a linear relationship between EKE and OHF is given by OHF = B ⋅ EKE + o.t., where B = 1.1 × 103 W m−4 s2. Third, an increase in OHF accelerates the reduction in sea-ice concentration (as well as sea-ice thickness), following ct = − C ⋅ OHF + o.t., where 2 (W s)−1. Combining these relationships, the evolution equation for sea-ice concentration exhibits exponential growth: ct = − C ⋅ OHF + o.t. = − C ⋅ B ⋅ EKE + o.t.= + C ⋅ B ⋅ A ⋅ c + o.t. Here, o.t denotes the combined contribution from other terms reflecting errors in the linear representation of processes that are, generally, nonlinear. Note that this feedback operates in the same way for positive concentration anomalies, leading to the amplification of sea-ice growth. We acknowledge that exponential growth in sea-ice concentration is not observed throughout the entire year due to other physical processes that provide an overall stabilizing effect. Strong external forcing can also modify the sign of anomalies depending on the season. The feedback strength described here is a product of the linear regression coefficients associated with the three stages: A ⋅ B ⋅ C = 4 × 10−9 s−1. This linear feedback analysis is likely a crude representation of the full dynamics, but it provides additional physical insight consistent with the eddy-induced, ocean-ice interactions discussed in earlier sections.Thus, a quantitative estimate of the linear sensitivity coefficients for all parts of the feedback loop follows. First, a reduced sea-ice concentration leads to an EKE increase following −2, which is small compared to the O(100 W m−2) atmospheric heat fluxes. However, ocean heat fluxes occur at the ice-water interface, and persistent OHFs as small as O(1 W m−2) can affect equilibrium sea ice thickness by as much as a meter . Also, the eddy-heat flux feedback involves sea ice concentration, not its thickness. The feedback timescale, (A⋅ B⋅ C)−1, is ~8 years, significantly longer than the seasonal cycle. Assuming that the feedback operates in MIZs over the course of a melt or growth season, the expected concentration change associated with the feedback can be crudely estimated as The eddy-heat flux feedback will be most relevant in regions of high eddy activity with large variations in sea ice concentration, e.g., marginal or seasonal ice zones. Since this is a linear feedback, it is expected to amplify the seasonal cycle of sea growth/melt, i.e., during melt season the sea ice melts faster due to the enhanced eddy-induced heating, while during growth season the sea ice grows faster due to the suppression of eddy-induced heating. The eddy feedback may be considered weak or secondary compared to radiative feedbacks: for monthly and domain-averages, the eddy feedback modifies OHF by several W mIn this study, we highlight the existence of a sea ice-eddy-heat flux feedback that is currently not represented in low-resolution climate models and may contribute to sea-ice prediction errors. As Arctic sea ice extent and thickness continue to decline, the key dissipation mechanisms for ocean eddies at the ice-ocean boundary layer is removed, resulting in more energetic upper-ocean mesoscale turbulence. In turn, the energized eddies enhance heat exchange between the subsurface ocean and the sea ice, accelerating its melt and constituting a positive feedback. The sea ice damping mechanism affects all eddies that have surface velocity expressions, including both mesoscale and submesoscale eddies. Thus, mesoscale-resolving Arctic Ocean models are expected to already contain the sea ice damping mechanism, and analysis of ice-eddy feedbacks in such models is highly desirable. However, we find that in winter, the OHFs are highly localized in submesoscale patches and hence models would need to be of appropriately-high resolution to represent their dynamics.55, and to accurately quantify their impacts on OHFs and tracer transport in climate models.On timescales longer than seasonal, this feedback may be limited by the availability of the sub-mixed-layer heat reservoir that could be drained due to increased efficiency of ocean-ice heat exchange. Thus, it is possible that with changing Arctic sea ice characteristics, the subsurface heat will shift to depths greater than those that can be accessed by mesoscale and submesoscale processes. In this case, atmospheric-driven heating of the surface ocean would dominate sea ice growth/melt. The extent to which these limiting cases will manifest in the future Arctic depends on details of atmosphere-ocean-ice coupling that is critically affected by both eddy stirring and small-scale turbulence. It is therefore imperative to develop and implement sea ice-aware parameterizations of upper-ocean eddies, both mesoscale and submesoscale59. This latter topic is particularly relevant in the emerging Arctic Ocean where MIZs now cover increasingly larger areas of the Arctic.We provided a simple but quantitative estimate of the EKE-OHF-sea ice concentration feedback by demonstrating the linear response of three key components of the feedback. The linear sensitivity analysis is based on a short model run, but sub-sampling in space permitted increased data samples. The linear sensitivity coefficients describing the EKE-concentration and the OHF-EKE relationships are unlikely to change significantly at longer timescales since these dynamics evolve over periods of several weeks to a month. Thus, the proposed feedback may impact not only seasonal sea-ice variability but also the long-term ocean-ice response to the overall trend of decreasing sea-ice concentration in the Arctic. We note that the overall role of the feedback in the seasonal development of sea ice or its decadal trends depends on the ocean and sea ice mean state. For example, models with biases towards larger fractional MIZ areas with thinner and low-concentrated sea ice are expected to be more sensitive to the eddy-heat flux feedback. Alternatively, if the model does not store sufficient heat under the mixed layer, EKE responses to changes in concentration would not necessarily be coupled to a change in the OHFs. The feedback loop may not be effectively closed in regions or times of the year where changes in sea-ice concentration are predominantly driven by external forcing, such as wind-driven sea ice advection. We thus caution that quantifying this feedback with greater certainty requires longer, high-resolution numerical experiments and, ideally, sensitivity experiments exploring sea ice rheology as this affects the critical concentration, the ice-ocean drag as this affects the eddy dissipation, and the ice-ocean heat exchange parameterization. This evidence that OHFs in the Arctic are dominated by localized filamentary and eddying structures provides a starting point for further studies on the interaction between sea ice and upper-ocean eddies. Dynamics of under-ice eddies are not well understood but, considering analogies with ice-free oceans, they should depend on such critical parameters as mixed layer depth, stratification, and strength of the mesoscale strain field—all of which are expected to change as the Arctic Ocean transitions to a more seasonal ice state. Longer-term trends in eddy dynamics in the changing Arctic Ocean are also expected to impact larger-scale circulations as well as biogeochemical cycles through lateral and vertical transport of nutrients and their impact on biomass production60; it is a version of the Massachusetts Institute of Technology General Circulation model (MITGCM)61. Its grid consists of 1/48th degree horizontal spacing (~0.8 km in the Arctic Ocean) and 90 vertical levels (1 m spacing near the surface increasing towards the bottom). The model was spun-up from a consecutive set of lower-resolution configurations62 and extended for over a year at its highest resolution, simulating a full seasonal cycle of the year 2012 with hourly output. The atmospheric forcing for the ocean-ice model comes from a 0.14 degree, 4-dimensional variational reanalysis product (European Centre for medium-Range Weather Forecasts63), interpolated onto the ocean grid from 6-hour time intervals. We note that the atmospheric forcing is of much larger length scales relative to the ocean resolution and hence might not provide sufficient energy to the ocean at relatively high frequencies and small length scales; in addition, since the ocean does not alter the atmosphere, a range of ocean-atmosphere-ice feedbacks might be missing. Tidal forcing was calculated off-line using a barotropic tidal model and prescribed by adding a corresponding atmospheric pressure perturbation to the ocean momentum equations; tidal forcing together with atmospheric winds are the main sources of internal gravity waves in the model that could interact with mesoscale and submesoscale variability.Results from this study make use of output from the LLC4320 model—a high-resolution global ocean and sea ice simulation that includes tides64 with VP rheology47; this high-resolution simulation generates a better representation of linear kinematic features as compared to lower-resolution VP models65. While the continuity assumption of VP-type rheologies becomes questionable with increasing model resolution beyond characteristic floe sizes, sea ice in seasonal ice zones was found to be mostly consistent with a VP rheology66, likely due to the smaller floe sizes as compared to pack ice. At sea ice model resolution of 1 km, particularly in the winter pack ice, we are approaching the floe scale where the sea ice behaves like a granular-type material with individual floes and anisotropic leads being present throughout. It would be ideal to use a discrete element model that could capture the granular nature of sea ice , but we do not yet have such modeling capability at basin scales. We can only speculate that in reality, the granular nature of sea ice floes may generate even more heterogeneous momentum and heat fluxes at the ocean-ice interface and lead to enhanced variability of mixed layer ocean currents, particularly in the submesoscale range.The sea ice has an active dynamic-thermodynamic model70 and sea ice dynamics65. Furthermore, the LLC4320 model simulates qualitatively similar winter-time submesoscale features as in idealized higher-resolution simulations71 in a much smaller domain; and its simulated salinity spectral slope of about k−3.5 is similar to the k−3 slope inferred from ITP observations72. Thus, we have confidence that the LLC4320 model, at least partially, captures the dynamical characteristics of the upper-ocean mesoscale and submesoscale turbulence under the sea ice.Critical sea ice parameters such as the strength and lead closing constants have been adjusted in the model to ensure stability and qualitative consistency with the observed sea-ice state. However, due to the extreme computational demands, the parameters of LLC4320 model could not be optimally adjusted to represent the best match with observations, resulting in regional pattern disagreements with observations, particularly in sea ice concentration fields. In addition, at less than 1 km grid, the model only marginally permits the development of high-latitude submesoscale flows, and hence higher-order statistical quantities, such as eddy-heat and momentum fluxes or spectral energy slopes and fluxes, may be resolution-dependent. Nonetheless, the model provides a unique opportunity for fundamental dynamical process studies as it simulates critical aspects of ocean eddiesζo  m, the sea ice drag is strong enough to dissipate upper-ocean eddies in a matter of several hours if their vorticity is confined only to the mixed layer and there were no other energy sources. However, a much longer time would be required to dissipate a subsurface mesoscale eddy because its surface vorticity expression becomes weaker under the influence of sea ice drag. From the perspective of ocean eddies, the heavily-packed sea ice could be considered a rough lid that induces dissipation proportional to eddy vorticity as wEk ~ −ζo in the limit of ∣ζi∣ ≪ ∣ζo∣. The magnitude of dissipation is an order of magnitude smaller in the summer because large areas of summer sea ice consist of relatively low-concentrated weakened ice with its vorticity strongly correlated to upper-ocean vorticity. It is the lack of dissipation in the summer that allows a strong surface signature of the underlying mesoscale eddy field. Note, atmospheric winds can drive the sea ice flow such that it provides a positive energy input into ocean geostrophic currents, but winds generally have a large-scale pattern, O(1000 km), and can not induce any significant sea ice vorticity at ocean eddy scales, O(10 km). Considering that ocean vorticity variance is dominated by eddies, the dissipative nature of winter sea ice is particularly intense over strong baroclinic eddying boundary currents  and hence must depend on the parameterization of sea ice strength P. We quantify the dependence of the transitional concentration on rheology by conducting a set of idealized experiments varying the parameter C* in ice pressure dependence on concentration 64. We prescribe the ocean currents obeying an idealized streamfunction ψ = sin(kx)*sin(ky) with a wavenumber k = 2π/40 km to represent the mesoscale eddy field. We then solve the sea ice equations of motion subject only to ocean stresses; no thermodynamic forcing is applied. We calculate the dependence of the correlation corr on the sea ice concentration, where ζo = ∇2ψ is the ocean vorticity and ζi is the equilibrium sea ice vorticity. The simulations are performed in a square, doubly-periodic domain 300 km in size and the equilibration is reached after ~1 h. The numerical model used is the MITgcm, which was configured to have the same sea ice rheology parameters as the LLC4320 simulation. The correlation and the transitional concentration are critically sensitive to the rheology parameter C*: for smaller C* the critical concentration significantly decreases and the region in which sea ice is mechanically affected by ocean eddies dramatically narrows (see Supplementary Section C* = 20, the transition between ice regimes occurs at a concentration of ~80% (Supplementary Figure C*, which is kept constant in VP rheology. Improving sea ice rheology and validating it with observations remains a significant challenge in sea ice modeling.The critical concentration, Equation  occurs wSupplementary InformationPeer Review FileDescription of Additional Supplementary FilesSupplementary movie 1


Propionibacterium acne (P. acne) causes severe acne vulgaris, serious public health, and psychological threat. A new lytic bacteriophage (phage), φPaP11-13, infecting P. acne, was isolated from the sewage management center of Xinqiao Hospital. It can form transparent plaque with diameters of 1.0 ~ 5.0 mm on the double-layer agar plate, indicating a robust lytic ability against its host. Transmission electron microscopy (TEM) showed that φPaP11-13 belonged to the Siphoviridae family . The one-step growth curve showed the incubation period was 5 h, and the burst size was 26 PFU (plaque-forming unit)/cell. Moreover, it exhibited tolerance over a broad range of pH and temperature ranges but was utterly inactivated by ultraviolet (UV) irradiation for 1 h. The whole-genome sequencing results revealed φPaP11-13 had a linear dsDNA with 29,648 bp length. The G/C content was 54.08%. Non-coding RNA genes and virulence factors were not found. Forty five open reading frames (ORFs) were identified after online annotation. This study reports a novel P. acne phage φPaP11-13, which has a robust lytic ability, no virulence factors, and good stability. The characterization and genomic analysis of φPaP11-13 will develop our understanding of phage biology and diversity and provide a potential arsenal for controlling antibiotics-resistant P. acne-induced severe acne vulgaris.Antibiotics-resistant  Acne vulgaris is the eighth most prevalent disease worldwide, and 85% of the patients are young people aged 12–24 . Severe Propionibacterium acnes (P. acnes), also known as Cutibacterium acnes, infection or imbalance of this commensal bacterium is one of the critical causes of the aggravation of acne vulgaris   . The gen France)  combined France) . The PacP. acne phage was screened and enriched as previously described  to remove any remaining bacteria. Then P. acne was cultured to the exponential phase (OD600 = 0.6) and was taken 1 ml to mix with 10 ml sewage filter liquor. The growth curve of host bacteria is in P. acne phages in the sewage samples. The next day, this mixture was centrifuged at 10,000 × g for 10 min at 4°C, and the supernatant was passed through 0.22-μm PES needle filters. The phage was purified and separated by picking single-plaque with the double-layer agar method  were pipetted on carbon-coated copper grids as instructed . After 24 h, phage titers were measured by the spot test (The multiplicity of infection (MOI) refers to the ratio of the plaque-forming unit (PFU) to the colony-forming unit (CFU). Firstly, the titer of pot test . The proThe phages and bacteria were mixed at the optimal MOI tested in the above experiments. Placed it in a hypoxia incubator and incubated for 5, 10, and 15 min. It was the optimal adsorption time when the phage titer was the lowest. Those experiments were repeated three times, and three parallel averages were taken under per-scale titers. The measurement data conformed to the normal distribution and were expressed as mean ± standard errors.P. acne at optimal MOI (0.0100) and adsorption at 37°C for optimal adsorption time (10 min). The mixture was centrifuged at 10000 × g for 60 s to clear unabsorbed phages from the supernatant. Then the residue was washed twice with BHI liquid medium on ice, resuspended by 5 ml BHI liquid medium, and cultured in a hypoxic incubator at 37°C. Samples were taken out at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 h after injection, and the spot test measured the titer. According to previous reports, the burst size was calculated based on the one-step growth curve  of each strain was mixed with 5 ml semi-solid agar and then poured into the bottom agar plate. 5 μl φPaP11-13 solution (1010 PFU/ml) was dropped onto the upper agar with more than three spots per plate. After the phage suspension was adsorbed, the plate was incubated in a hypoxic incubator at 37°C for 24 h.Spot test and double-layer agar plate were used to determine the host range of φPaP11-13. Sixteen strains of Phage DNA was extracted using the standard Protease-K/SDS DNA extraction method . The nucPhageterm  was usedLiquid nitrogen was added to the phage particle, and then it was ground to powder. Then the phage particle was lysed by ultrasound, and a BCA kit measured its protein concentration. 5 μl of 4 × loading buffer and 2% SDS were added to the sample and then electrophoretic. The silver dyeing method was transferred into the chromogenic solution for about 10 min at room temperature, and clear bands were finally visible. Then the cut protein bands were tested by LC–MS/MS system  for phage major protein analysis. Then cross-checking underwent between LC–MS/MS results and whole genome annotation.The whole genome of Pacne11-13 underwent sequencing. And AMR genes were annotated and listed in P. acne phage was isolated from the sewage management center at Xinqiao Hospital and named “φPaP11-13.” This phage can form transparent circular plaques , demonstrating the phage has a broad host range , H-type lectin domain-containing protein (ORF28), tail family protein (ORF30), tape measure protein (ORF31), major tail protein (ORF27), capsid protein (ORF39), scaffold protein (ORF40), MuF-like minor capsid protein (ORF42), and portal protein (ORF43). The metabolic-related group included HNH endonuclease (ORF1), P D-(D/E) X.K. nuclease family protein (ORF10), DNA Primase (ORF15), exonuclease (ORF19), helix-turn-helix DNA binding domain protein (ORF20), terminase large subunits (ORF44), and terminase small subunits (ORF45). The cleavage proteome included Amidase (ORF25) and Holin (ORF24). Other function groups include collagen triple helix repeat protein (ORF26) and sigma factor (ORF22). The annotation information of φPaP11-13 was uploaded to GenBank with the accession number: ON557706. The whole genome is visualized in SDS-PAGE was applied to verify the major proteins of φPaP11-13. The results showed clear protein bands and normal distribution , indicatP. acne phage belonging to the Sipoviridae family, were on the same branch, with 100% reliability and short genetic distance, revealing the homology between φPaP11-13 and φPHL030N00. Collinearity and phylogenetic analysis confirmed P. acne phage φPaP11-13 as a member of the Sipoviridae family.By comparing with the whole genome sequence in the NCBI database, the similarity between φPaP11-13 and known Sipoviridae family phages ranged from 41 to 98% . The twoP. acne is not only a commensal bacterium that inhabits the sebaceous follicle but is also one of the primary acne triggers , in which phage showed good efficacy . To understand the feasibility of phage therapy, it is necessary to comprehend phage’s biological characteristics. According to their characteristics, different administration methods, such as oral administration, injection, and application, are selected to reduce the influence on bacteriophage activity. Additionally, φPaP11-13 is functionally stable over a wide range of pH values and temperatures, potentially suitable in the human physiological environment. And the inactivation of φPaP11-13 under ultraviolet irradiation suggests a further application with sunscreen or at night to ensure the therapeutic effect on severe acne vulgaris. The stability of bacteriophages are mainly determined by their morphology and structure. Most P. acne phages reported belonged to the Siphoviridae family, sharing a similar morphology, with long tails and icosahedral heads, and thus performed the same stability  can be found at: This is an original article on bacteriophages and bacteria. For this type of study, the requirement for ethics approval is waived by the Medical Ethics Committee of the Second Affiliated Hospital  of Army Medical University, PLA.DL, YZ, and ZY conceived and designed the experiments. DL performed the experiments. JZ, RL, KC, YL, YS, and XS analyzed the data. DL and ZY wrote the paper. All authors contributed to the article and approved the submitted version.This work was supported by the National Natural Science Foundation of China (grant nos. 82002051 and 81772073), the Natural Science Foundation of Chongqing CSTC (cstc2021jcyj-msxmX0655), the Doctor Through Line Project of Chongqing CSTB (CSTB2022BSXM-JCX0019), the Foundation of Open Projects from State Key Laboratory of Trauma, Burns and Combined Injury (No. SKLKF201918), the Novel Clinical Technology Category of Army Medical University (XJSZR1206), and the Talent Training Project of Army Medical University (2019R031).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.https://www.frontiersin.org/articles/10.3389/fmicb.2022.1065386/full#supplementary-materialThe Supplementary material for this article can be found online at: Supplementary Figure S1The grown curve of Pacne11-13.Click here for additional data file.Click here for additional data file.Click here for additional data file.Click here for additional data file.


The FRN 137Cs technique, which has proved its efficiency in estimating erosion rates over the last 50–60 years, was used for the first time in Palestine to measure rates of erosion and deposition. The activity of 137Cs was measured by gamma spectrometry using an HPGe detector. For the reference site, the 137Cs inventories ranged between 2499 and 4086 Bq/m2. The average value of the reference site is 3315 ± 410 Bq/m2, which corresponds to a coefficient of variance of 12%, suggesting that the reference site is well representative for estimating 137Cs fallout. This 137Cs amount is too high for bomb-derived fallout and indicates that a significant part of the deposition is from the Chernobyl accident. The 137Cs inventories at both studied sites (terrace site and foot slope site) are significantly lower than those of the reference site. For the terrace site, the inventories are found between 1707 and 2749 Bq/m2, while for the slope site they are between 1050 and 2617 Bq/m2. The lower 137Cs values at both studied sites than values at the reference site indicate that the entire areas of both study sites are eroded and no depositional activity occurs.Soil erosion is a serious problem in Palestine. It is enhanced mainly by poor farming practices used in upland agricultural areas occupying the Central Highland of Palestine. The objective of this study is to assess the impact of terracing on soil erosion and deposition rates in the Al-Yamoun area (the Northern West Bank) using the fallout radionuclides cesium -137 (FRN  Agriculture is an important cultural tradition vital to the economy of the West Bank, Palestine. Also, agriculture plays a vital role in the region's future. Palestinians are coping in creative ways  every daWithin this context, and in order to provide a comprehensive assessment of the magnitude of these problems and to support the selection of effective soil conservation measures, quantitative data on the extent and rates of soil erosion under various agroecological conditions and land use systems were needed . IntegraThe study area is located in the Central Highland in the Jenin Province, which receives annual precipitation of about 300 mm . The samThe sampling design is as follows:Grid samplingof 1.5 m (24 samples) (3 × 8), bulk samples, 30 m depth, and a distance between two points is of 1.5 m.Sampling along 3 transects containing 8 points in each transect (24 soil samples), bulk samples, 30 cm depth, and a distance of 1.5 m between two points.Sampling along 3 transects containing 8 points in each transect (24 soil samples), bulk samples, 30 cm depth, and a distance of 1.5 m between two points.137Cs was performed by gamma spectrometry using an HPGe detector (45 efficiencies) by the Centre National de l'Energie des Sciences et des Technique Nucleaires (CNESTEN), Morocco. Tennelec/Nucleus HPGe (184 cc) planar-type coaxial intrinsic germanium detector was used. The 137Cs activity was measured by its gamma emission at 662 keV. Background counts were made at regular intervals to ensure the maintenance of low background characteristics. Each soil sample was counted for 20000 s. The Cs inventory A (Bq·m−2) was calculated using the following equation:137Cs activity concentration of the sample (in Bq·kg−1), M is the total dry mass of the collected soil core (in kg) and S is the cross-section of the sampling tube (in m2)Physical preparation of the soil samples was performed at the Palestine National Agricultural Center (NARC) including drying and light grinding. Then, samples were oven dried at 105 degrees Celsius, grinded, sieved (<2 mm), and homogenized. Radionuclide analysis of 137Cs approaches have been reported in several papers [137Cs inventories and the 137Cs depth distribution. Two methods are used. The simpler method considers the fixed 137Cs fallout input and stable 137Cs profile distribution. The depth distribution over the soil profile is mathematically described [137Cs reference value removed at the examined site [137Cs fallout and (2) the gradual postdepositional redistribution of 137Cs within the soil profile, which is caused predominantly by bioturbation and several other processes. This approach is used by the Diffusion and Migration Model (DMM) [137Cs are directly proportional. Models based on this concept are called the Proportional Model (PM). More complex approaches involve a mass balance concept, which considers the temporal dynamics of 137Cs inputs and outputs resulting in the time-variant concentration of 137Cs in soil [137Cs loss and soil loss caused by erosion. The 137Cs concentration in soil is controlled by several processes [137Cs , (3) removal of freshly deposited 137Cs by erosion prior to its incorporation into the plough horizon by tillage, and (4) incorporation of subsoil material free of 137Cs or having low 137Cs content into the eroded ploughed horizon by tillage [Numerous models were established to analyze soil erosion . The mail papers . The calescribed . If thisel (DMM) . The cal in soil . These crocesses –17. Most tillage .137Cs time-variant concentration in soil and consider some but not all processes and factors controlling it [The Mass Balance Models (MBM) were developed in the mid-1980s. Different models use different approaches to handle the lling it , 19, 20.lling it  are used2) into soil erosion or deposition rates (in t/ha/yr), conversion models were used. First, the Proportional Model (PM) was used to have preliminary results about soil erosion, in accordance with equations 2) into sX is the percentage reduction in total 137Cs inventory (defined as (Aref -A)/A ∗ 100), d is the depth of the plough or cultivation layer (m), B is the bulk density of the soil (kg·m−3), T the time elapsed since the start of 137 Cs accumulation (yr), Aref, represents the local reference inventory (Bq·m−2), and A is the total inventory measured at the sampling point (Bq m−2). P represents the particle size correction factor for erosion. This model does not require many parameters, but it is not realistic as he neglected some processes or phenomena related to 137Cs behavior and erosion processes in cultivated sites.The basic equation  of the P137Cs was modified to take the Chernobyl contribution into account. The results given by both models for both sites 1 and 2 are reported in t represents the time since 1963, B is the bulk density of the soil (kg·m−3), and d is the depth of the plough or cultivation layer (m). X is the percentage reduction in total 137 Cs inventory (defined as (Aref -A)/A ∗ 100) 137Cs activity per unit area (Bq/m2); R = erosion rate (kg/m2. yr) d = cumulative mass depth, representing the average plough depth (kg/m−2) λ = decay constant for 137Cs (yr−1); I (t) = annual 137Cs deposition flux (Bq/m2 yr); Γ = percentage of the freshly deposited 137Cs fallout removed by erosion before being mixed into the plough layer; P = particle size correction factor.In addition, the Chernobyl contribution was not included when applying this model. In this case, Mass Balance Models were used (equation ) and, mo137Cs concentration (in Bq/kg), the bulk density of the sample, and the depth of the core. An average bulk density was calculated for each type of site. There are about 1160 kg/m3, 1240 kg/m3, and 1190 kg/m3 for a reference site, site 1, and site 2, respectively.The inventories of the samples were calculated from the 2) are given in 2. The average value of the reference site is 3315 ± 410 Bq/m2, which corresponds to a coefficient of variance of about 12%. This coefficient of variance can be considered as low, confirming the low variability and low disturbance of the selected reference site. The high inventory associated with the reference site suggests that the fallout 137Cs deposited in this region is the result of both old nuclear weapon tests conducted in the 1950s–1960s and the Chernobyl disaster that occurred in 1986. Taking into account the average rainfall in this region (Jenin Province) of about 300 mm, the inventory estimated by prediction using conversion models is about 897 Bq/m2. It means that the contribution of Chernobyl is about 2418 Bq/m2, which represents around 73% of the total reference inventory. Concerning study site 1 and site 2, the inventories are significantly lower than those of the reference site (see 137Cs inventory along 3 transects for each site and the mean reference inventory value. For site 1, inventories are found between 1707 and 2749 Bq/m2, while for the site 2, inventories are found between 1050 and 26117 Bq/m2. In comparison, all the inventories obtained are lower than the reference value (The results of all inventories (Bq/msite see , especiace value , indicat137 Cs concentrations in the soil within the cultivated layer, resulting from the assimilation of soil from below the originally cultivated depth due to surface lowering by erosion; thus, the results obtained by this model in the present study likely underestimate the actual rates of soil loss. The Mass Balance approach that takes into account the effect of mixing the subsoil containing no 137Cs from below the plough depth into the plough layer gave higher values for soil loss rate, as is observed in some other reports [As previously reported by Nouira et al. , the Pro reports , 22.137Cs distribution at the sites confirmed that the 137Cs tracking procedure can be effectively used to assess soil erosion and deposition rates. The application of the 137Cs tracking system enabled us to quantify the extent of soil erosion in the Northern Palestine region. For the reference site, the inventories ranged between 2927 and 4086 Bq/m2. The average value of the reference site is 3315 ± 410 Bq/m2, which corresponds to a coefficient of variance of about 12%, suggesting that the fallout 137Cs deposited in this region is a result of both old nuclear weapon tests conducted in 1950s–1960s and the Chernobyl disaster that occurred in 1986.137 Cs tracking technique is a useful erosion model for the Northern Palestine region. This data can be used to refine erosion control guidelines influencing the selection of a vast array of management practices by an agricultural producer, such as tillage, fertilizer application, crop rotation, plant population, and structures. Thus, the future work, which will be carried out in phase–II of the project, highly recommends the selection of more locations in Gaza and the West Bank in order to generate a soil erosion map of Palestine. This result will also be presented to legislators and decision makers within the government to implement appropriate soil erosion solutions.Finally, the


Background: The process of talent identification in ice hockey occurs during middle adolescence when players are selected to participate in “off-season” evaluation camps, where coaches observe their fitness levels and status of development. Recently, the Quebec ice hockey federation opted for a holistic approach by evaluating players based on three criteria: (1) fitness, (2) skating abilities and (3) personality traits and psychological assets. This study aimed to analyze the discriminant validity of a multi-dimensional talent identification testing protocol in competitive ice hockey. Method: Data were collected from 160 adolescent hockey players who took part in Team Quebec summer evaluation camps. Off-ice fitness, skating abilities and psychological variables were measured on two consecutive days. Descriptive statistics, group comparisons  and discriminant analyses (selected versus non-selected) were performed. Results: No differences were observed among males in which selected players were similar to non-selected. Results from discriminant analyses also showed no discriminant function for male players. For females, selected players displayed higher fitness, on-ice agility and psychological characteristics. Nine performance markers were significantly discriminant. Conclusions: A holistic evaluation protocol allows for the discrimination of selected and non-selected players in elite ice hockey. Developing more discriminant tests is a promising avenue of research in male ice hockey. Knowing the factors that are associated with team selection in competitive ice hockey allow to focus on the specific attributes to work with young promising players. Ice hockey involves high-intensity, intermittent actions that require players to perform at superior technical and tactical levels. Accordingly, excelling in ice hockey necessitates a vast repertoire of physical attributes, technical–tactical skills  and psychttps://www.iihf.com/en/static/5324/survey-of-players; accessed on 17 December 2021) and hundreds of professional leagues across the world, access to professional hockey is among young hockey players’ long-term objectives. As for most sports, national team selections, world championships and Olympic Games performance and the number of drafted players in the National Hockey League  were the criteria used by hockey federations to evaluate the quality of their development model. There is a wealth of past research on the fitness status of professional ice hockey players [In the last two decades, ice hockey has become increasingly popular internationally and is now played by some 1.5 million registered players from more than 75 different countries. With over 900,000 players under the age of 20 , where the most talented players display their skills before hockey coaches and stakeholders, is a good example. The world’s top hockey countries  also have development camps where players are evaluated at the early stages of sports expertise. Indeed, many countries have specific protocols to conduct periodic evaluation or development camps that serve to guide hockey federations in terms of future national team selections . Camps such as these are first-rate opportunities to develop performance standards for both off-ice fitness and on-ice skills [2max, relative peak power and height, that determined success in the Polish men’s national team selection camp [In line with these standards and the complex nature of the sport, the pathway to elite ice hockey is a long-term process that needs to start at a young age . As withe skills . In addiion camp . Recentlion camp  conducteion camp  and thation camp . As a reDespite the multiple assessment methods and their usefulness in the talent identification process, less is known about the discriminant capacity of psychological variables. Mustafovic and colleagues  suggestehttps://www.iihf.com/en/tournaments; accessed on 4 January 2022). The purpose of this study is twofold. First, it aimed to describe the fitness, on-ice skating abilities and psychological characteristics of the male and female adolescent players that were pre-selected to take part in the 2021 Équipe Québec development evaluation camp: https://www.hockey.qc.ca/fr/page/excellence/equipe_quebec.html; accessed on 21 July 2021). This study aimed to investigate the athlete evaluation process in Canadian hockey  in the early phase of the talent identification process. Because ice hockey is Canada’s national winter sport, excellence is achieved through the rigorous observation and monitoring of player development. Every four years, each province develops a team composed of players under 15 years old for males and under 16 years old for females to compete at the Canada Games. In other years, Hockey Canada asks the provincial federations to organize development camps regarding the evaluation process for all international events, including the Hlinka Gretzky Cup for men, the Summer Series against USA for women and, of course, the World Junior Championships  were invited to the Team Quebec evaluation camp. The criteria for invitation refer to players’ regular season performances. Indeed, both prospect  camps serve as an important talent identification stage to determine those who will represent Quebec in national competitions. A week before each camp, players were informed about the research project during an online information meeting. Those who agreed to participate were asked to sign a consent form . The project was approved by the ethics board of the researchers’ institution (CER-21-278-07.09). The full protocol included three categories of measures (as described in the following section): (1) off-ice fitness tests (8 tests), (2) on-ice skating abilities (2 tests) and (3) psychological attributes (6 measures). The testing procedure was completed on three separate days  during one weekend camp.2max and (4) upper limb power. For on-ice fitness, two skating tests were used to measure skating speed and agility. Finally, two categories of psychological measures were assessed: personality traits and grit.Measures were selected based on two criteria. The first was related to Hockey Canada’s standards to ensure that some tests were aligned with those of other provinces. The second was related to the scientific literature on testing and refers to specific components identified as potential determinants of performance  in ice hockey. For off-ice fitness, ten variables were measured and divided into four categories: (1) anthropometric measures, (2) lower limb power, (3) running and VOAnthropometric measures are commonly used in player evaluation to assess the body composition of a cohort of ice hockey players ,26,27,28Off-ice fitness testing protocol see : Before https://link.nhl.com/centralscouting/public/; accessed on 10 December 2021). https://www.power-systems.com/shop/product/vertec, accessed on 10 December 2021) was used to assess this variable. Upper body strength, power and endurance also play a natural role in ice hockey [https://link.nhl.com/centralscouting/public/; accessed on 10 December 2021) [https://movefactorx.com/, accessed on 10 December 2021) was used in this regard. Muscular power (upper and lower body): Since skating is a core element of performance, several studies have examined lower body power as a predictor of performance ,30,31,32e hockey . Indeed,er 2021) . The seaer 2021) . A Ballihttps://stalker.sport/pro-ii/, accessed on 10 December 2021) combined with Swift Speedlight photocells  . For the off-ice agility, we used the Pro-Agility Drill 5-10-5 [Aerobic capacity, speed and agility: In addition to lower body power, aerobic capacity  and runnl 5-10-5  with a sOnly two on-ice tests were chosen for the study. In the interest of efficient time management, this part of the testing protocol was limited to 20 to 24 players on the ice for 50 min of ice time. The 44 m sprint and the Finnish Vierumaki’s ice hockey centre of excellence skating agility test were selected. Four sessions of ice time were needed to screen all the participants, both males and females.https://stalker.sport/pro-ii/ (accessed on 10 December 2021)) combined with three pairs of Swift Speedlight photocells  (Swift Performance: https://swiftperformance.com/ (accessed on 10 December 2021)), one at the start, a second at 6 m to assess the 0–6 m acceleration and a third at 44 m. Skating speed and acceleration: The 44 m sprint  was meashttps://iihce.fi/suomeksi/Testaaminen/Pohjola-leiritestit/tabid/1150/Default.aspx#/material/872/2401; accessed on 4 January 2022)  and participants were given one week before camp to ensure they were in the right frame of mind. Two psychological constructs were measured: personality traits ,42 and gWe calculated descriptive statistics for all data and verified the distributions to identify potential outliers. We also verified the distribution and checked whether assumptions of normality had been violated. The preliminary results indicated no major deviation from normality regarding all off-ice and on-ice measures. Few data were missing because all players took part in the evaluation camp. To verify the contribution of each part of the protocol related to talent identification, as well as the discriminant capacity of each group of components, discriminant analyses were conducted in three consecutive phases. All analyses were performed using SPSS software and based on the recommendations of Tabachnik and Fidell . Discrimheight = 68.03, p < 0.001), but no differences were observed regarding body weight. Proportions for player positions were similar across groups owing to the specificity of ice hockey in which a usual roster is mainly composed of 47 as forwards, 31 as defense and 8 as goaltenders. For the male cohort, goaltenders tended to be taller and heavier than defense and forwards . No player-position-related differences were observed regarding the anthropometric profile of the female cohort. p < 0.01 or 0.001). The same pattern was observed regarding the on-ice skating tests, which showed that boys were faster, had better acceleration and were more agile. Male goaltenders also performed better than female goaltenders on the shuffle tests. However, different patterns were observed when comparing participants’ personality traits. The female cohort displayed higher scores for three traits: extraversion (t(df) = 2.41(187), p = 0.017), conscientiousness (t(df) = 2.16(187), p = 0.032) and openness (t(df) = 3.55(187), p < 0.001). Comparisons between the selected and non-selected players  were presented in the sections on discriminant analyses. Finally, we compared all measures according to the players’ positions  and found no significant differences , suggesting that players’ fitness and abilities were similar for males and females. (df) = 2.80(2), p < 0.10). No significant discriminant functions were noted in each of the five proposed models. In model 4, none of the variables showed a significant discriminant function, but the selected players had higher scores for grit (F(df) = 3.05, p < 0.10). We retained loadings higher than 0.3 to identify the most discriminating variables, which are identified in 2max), leg power, speed and agility were identified as discriminant factors. On the ice, skating speed and agility had a significant discriminant function. For psychological measures, agreeability and grit have a significant discriminant function. Each of the five models correctly classified 52–74% of selected players. In summary, models 2,3,4 and 5 displayed significant discriminant functions.As shown in In ice hockey, team selection is a complex process that involves the observation and assessment of multiple variables. According to Tarter , the comThe first part of our study shows that fitness measures have similar patterns when male and female participants are compared. As expected, boys displayed higher scores than girls, which can be explained by the physical maturation and physiological aspects that favor male athletes at this stage . With thThe second part of the study was designed to verify the discriminant capacity of each variable tested in the selection process. Results from our analyses offer interesting insights, particularly because the substantial differences they revealed were based on gender. In the male cohort, we found that not all five models were discriminatory. At first glance, this suggested that the current protocol with the current group of players did not contribute definitively to the selection process in the male sample. However, certain measures, including muscular strength, aerobic capacity, skating agility/acceleration and grit, tended to be more strongly associated with the players selected during the process. The picture was different in the female sample, as the fitness tests, running skills and skating performance successfully classified between 62 and 74% of the selected athletes. On a different note, the higher grit score of the selected male players was to be expected since this was noted in several studies. However, a higher conscientiousness score would also have been expected regarding these players, as it is the strongest predictor of success in sports and is generally associated with grit. Interestingly, the protocol’s discriminant capacity was significant in the female cohort. The three personality traits that appeared to distinguish the selected female players were agreeableness, conscientiousness and neuroticism, which is plausible in a team sport context. These three traits are generally associated with success in team sports, as conscientiousness predisposes players to invest more effort, a low level of neuroticism provides greater emotional stability under pressure and agreeableness promotes healthy relationships with teammates . The facIn our view, the divergent results (related to the discriminant capacity of each protocol) can be explained from a gender perspective using socio-demographics. Even if the initial samples (selected and non-selected) were similar in size, they were not similar regarding the representation of the province’s pool of elite players since Quebec had over 450 male players classified as U15–U18 elite players , which iDespite its contribution, this study had limitations. The first was the potential selection bias. To participate in the study, players had to be registered in a league governed by Hockey Quebec. This means that the participants were engaged in a very similar pattern of sports development, possibly leading to an almost identical athletic profile, reducing the discriminant capacity of the protocols, especially among males. The Hockey Quebec development model for males was implemented in 2011, whereas its implementation for females is far more recent (2015). Another limitation of the sample concerns the players’ age groups and physical maturation. Even if further analyses from the current database confirm the physical maturation of most participants, we believe the maturation process is an important factor to consider, especially in sports like ice hockey, where physicality prevails. Additionally, we recognize that certain key talent indicators are missing in the present investigation. As Tarter stipulates , game obIn Canadian hockey, talent identification starts in late adolescence and is a crucial stage in the development of sport expertise. Player development in Quebec is monitored in off-season (summer) evaluation camps designed to identify the province’s best prospects for future competitions. Knowledge about the discriminant capacity of each component of talent is crucial for stakeholders  in talent detection camps. This study refined our understanding of talent identification and revealed that the discriminant capacity of protocols differs based on gender. Interestingly, it showed that multiple components of sport talent help to classify the female players who emerged in the first phase of the selection process. Lower body power, upper body strength, running abilities and on-ice skating efficiency are useful components of the selection process. Inversely, such protocols are less conclusive for male cohorts, suggesting that further research is needed in this area. Future investigations can build on this study by focusing on variables assessed through game observation and other key factors for distinguishing the most promising talents.