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We present an analysis to extract kaon parton distribution functions (PDFs) for the first time using meson-induced Drell-Yan and quarkonium production data. Starting from the statistical model first developed for determining the partonic structure of spin-1/2 nucleon and later applied to the spin-0 pion, we have extended this approach to perform a global fit to existing kaon-induced Drell-Yan and $J/\psi$ production data. These data are well described by the statistical model, allowing a first extraction of the kaon PDFs. We find that both the Drell-Yan and the $J/\psi$ data favor a harder valence distribution for strange quark than for up quark in kaon. The kaon gluon distribution is further constrained by the $J/\psi$ production data. In particular, the momentum fraction carried by gluons is found to be similar for pion and kaon., Comment: 6 pages, 3 figures. arXiv admin note: text overlap with arXiv:2202.12547

Bud dormancy is crucial for winter survival and is characterized by the inability of the bud meristem to respond to growth-promotive signals before the chilling requirement (CR) is met. However, our understanding of the genetic mechanism regulating CR and bud dormancy remains limited. This study identified PpDAM6 (DORMANCY-ASSOCIATED MADS-box) as a key gene for CR using a GWAS (Genome-Wide Association Study) analysis based on structural variations (SVs) in 345 peach (Prunus persica (L.) Batsch) accessions. The function of PpDAM6 in CR regulation was demonstrated by transiently silencing the gene in peach buds and stably overexpressing the gene in transgenic apple (Malus × domestica) plants. The results showed an evolutionarily conserved function of PpDAM6 in regulating bud dormancy release, followed by vegetative growth and flowering, in peach and apple. The 30-bp deletion in the PpDAM6 promoter was substantially associated with reducing PpDAM6 expression in low-CR accessions. A PCR marker based on the 30-bp indel was developed to distinguish peach plants with non-low and low CR. Modification of the H3K27me3 marker at the PpDAM6 locus showed no apparent change across the dormancy process in low- and non-low-chilling requirement cultivars. Additionally, H3K27me3 modification occurred earlier in low-CR cultivars on a genome-wide scale. PpDAM6 could mediate cell-cell communication by inducing the expression of the downstream genes PpNCED1 (9-cis-epoxycarotenoid dioxygenase 1), encoding a key enzyme for ABA biosynthesis, and CALS (CALLOSE SYNTHASE), encoding callose synthase. We shed light on a gene regulatory network formed by PpDAM6-containing complexes that mediate CR underlying dormancy and budbreak in peach. A better understanding of the genetic basis for natural variations of CR can help breeders develop cultivars with different CR for growing in different geographical regions.

Cytomegalovirus (CMV) viremia is associated with a higher mortality rate and prolonged intensive care unit (ICU) stay for critically ill patients. CMV infection causes transient but substantial immunosuppression for transplant recipients, increasing risk of fungal infection. The association between CMV viremia and invasive pulmonary aspergillosis (IPA) for critically ill patients is still unknown.We retrospectively analyzed patients received bronchoalveolar lavage (BAL), galactomannan test, influenza survey and blood CMV viral load test in ICUs of a university hospital between April 2017 and May 2020. Independent risks for IPA were analyzed by multivariable logistic regression.A total of 136 patients were included. Twenty-one patients had IPA, 48 patients had CMV viremia and 22 patients had influenza. In a multivariable logistic regression model, patients with CMV viremia or influenza had higher IPA risk (adjusted odds ratio, 3.98 and 8.72; 95% CI, 1.26-12.60 and 2.64-28.82; p value = 0.019 and0.001, respectively.). Patients with detectable CMV in BAL fluid did not have higher IPA risk (crude odds ratio, 0.95; 95% CI, 0.33-2.79; p value = 0.933). After stratifying patients by CMV viral load, the IPA risk is higher for patients with higher viral loads. There is an additive synergistic effect on IPA risk between CMV viremia and influenza infection.For critically ill patients, CMV viremia is an independent risk factor of IPA. Patients with higher blood CMV viral loads have a higher risk of IPA. CMV viremia and influenza have an additive synergistic effect for IPA risk in critically ill patients.

Background Pendelluft occurs in patients with acute respiratory distress syndrome (ARDS) during spontaneous breaths. Quantifying pendelluft in ARDS patients has not been performed before. We combined electrical impedance tomography (EIT) and respiratory mechanics monitoring to quantitatively examine pendelluft in trigger and reverse triggering breaths in mechanically ventilated patients with ARDS. Methods EIT and respiratory mechanics measurements were analyzed in 20 mechanically ventilated patients with ARDS during transitioning from controlled to spontaneous breaths following discontinuance of myorelaxant under volume-cycled ventilation. Breath selection was based on 4 levels of esophageal pressure swing (∆Pes). These were rest (0 cm H2O, breaths = 200), low (2O, breaths = 471), moderate (≥ 5, < 10cm H2O, breaths = 906), and high effort (≥ 10cm H2O, breaths = 565). A total of 2,142 breaths were analyzed. Results The pendelluft response to breathing efforts varied and was significantly greater in trigger versus reverse triggering breaths (3.9 ± 6.8 vs 1.9 ± 2.8 ml, respectively, p es slope (ml/cmH2O). For trigger breaths, high pendelluft group (n = 9, slope 0.7 to 2.4 ml/cmH2O) was significantly associated with lower peak airway/plateau pressure and lower respiratory system/lung elastance than low pendelluft group (n = 11, slope − 0.1 to 0.3 ml/cmH2O). For reverse triggering breaths, there was no difference in respiratory mechanics between high (n = 4, 0.49 to 2.53 ml/cmH2O) and low pendelluft (n = 12, -0.22 to 0.25 ml/cmH2O) groups. The prediction of pendelluft by ∆Pes was characterized by a low positive predictive value. ARDS cases with high effort-related pendelluft were uncommon. The prediction of pendelluft was not significant in reverse triggering breaths. Conclusions Effort-related pendelluft should be individualized. Pendelluft is higher in trigger breaths than reverse triggering breaths. For trigger breaths, high pendelluft is likely to occur in ARDS patients with lower lung elastance and lower peak airway/plateau pressure. However, ARDS cases with high effort-related pendelluft were uncommon in our study population.