Absolute calibration of Fujifilm BAS-TR image plate response to laser driven protons up to 40 MeV.

Image plates (IPs) are a popular detector in the field of laser driven ion acceleration, owing to their high dynamic range and reusability. An absolute calibration of these detectors to laser-driven protons in the routinely produced tens of MeV energy range is, therefore, essential. In this paper, the response of Fujifilm BAS-TR IPs to 1-40 MeV protons is calibrated by employing the detectors in high resolution Thomson parabola spectrometers in conjunction with a CR-39 nuclear track detector to determine absolute proton numbers. While CR-39 was placed in front of the image plate for lower energy protons, it was placed behind the image plate for energies above 10 MeV using suitable metal filters sandwiched between the image plate and CR-39 to select specific energies. The measured response agrees well with previously reported calibrations as well as standard models of IP response, providing, for the first time, an absolute calibration over a large range of proton energies of relevance to current experiments.

Calibration of BAS-TR image plate response to GeV gold ions.

The response of the BAS-TR image plate (IP) was absolutely calibrated using a CR-39 track detector for high linear energy transfer Au ions up to ∼1.6 GeV (8.2 MeV/nucleon), accelerated by high-power lasers. The calibration was carried out by employing a high-resolution Thomson parabola spectrometer, which allowed resolving Au ions with closely spaced ionization states up to 58+. A response function was obtained by fitting the photo-stimulated luminescence per Au ion for different ion energies, which is broadly in agreement with that expected from ion stopping in the active layer of the IP. This calibration would allow quantifying the ion energy spectra for high energy Au ions, which is important for further investigation of the laser-based acceleration of heavy ion beams.

Food insecurity and mental health during the COVID-19 pandemic in cystic fibrosis households.

BACKGROUND: The COVID-19 pandemic impacted many households due to shelter-in-place orders and economic hardship. People with cystic fibrosis (CF) experienced increased food insecurity compared to the general population before the pandemic, even though adequate food access is needed to maintain nutrition goals associated with improved health-related outcomes. Little is known about the impact the pandemic had on the food insecurity of people with CF and their families. OBJECTIVE: To investigate how the COVID-19 pandemic impacted food insecurity, mental health, and self-care in people with CF. METHODS: Adults with CF and parents/guardians of children with CF were recruited via social media to complete online questionnaires from May 2020 to February 2021. Questionnaires in English and Spanish included USDA 2-question food insecurity screening, Patient Health Questionnaire-4 for mental health screening, and directed questions on the impact of the pandemic. RESULTS: Of 372 respondents, 21.8% of the households experienced food insecurity during the pandemic compared to 18.8% prepandemic (p < .001). More food insecure patients with CF reported weight loss (32.1% vs. 13.1%, p < .001), worse airway clearance adherence (13.6% vs. 5.8%, p < .01), and worse medication adherence (12.4% vs. 1.7%, p < .01) compared to food secure patients. Food insecure subjects were more likely to have an abnormal mental health screen compared to food secure subjects (53.1% vs. 16.2%, p < .001). CONCLUSION: Food insecurity increased in the CF population during the COVID-19 pandemic. Food insecure subjects reported worse mental health and self-care during the pandemic compared to food secure subjects.

DNA DSB Repair Dynamics following Irradiation with Laser-Driven Protons at Ultra-High Dose Rates.

Protontherapy has emerged as more effective in the treatment of certain tumors than photon based therapies. However, significant capital and operational costs make protontherapy less accessible. This has stimulated interest in alternative proton delivery approaches, and in this context the use of laser-based technologies for the generation of ultra-high dose rate ion beams has been proposed as a prospective route. A better understanding of the radiobiological effects at ultra-high dose-rates is important for any future clinical adoption of this technology. In this study, we irradiated human skin fibroblasts-AG01522B cells with laser-accelerated protons at a dose rate of 109 Gy/s, generated using the Gemini laser system at the Rutherford Appleton Laboratory, UK. We studied DNA double strand break (DSB) repair kinetics using the p53 binding protein-1(53BP1) foci formation assay and observed a close similarity in the 53BP1 foci repair kinetics in the cells irradiated with 225 kVp X-rays and ultra- high dose rate protons for the initial time points. At the microdosimetric scale, foci per cell per track values showed a good correlation between the laser and cyclotron-accelerated protons indicating similarity in the DNA DSB induction and repair, independent of the time duration over which the dose was delivered.

Pulmonary Metagenomic Sequencing Suggests Missed Infections in Immunocompromised Children.

BACKGROUND: Despite improved diagnostics, pulmonary pathogens in immunocompromised children frequently evade detection, leading to significant mortality. Therefore, we aimed to develop a highly sensitive metagenomic next-generation sequencing (mNGS) assay capable of evaluating the pulmonary microbiome and identifying diverse pathogens in the lungs of immunocompromised children. METHODS: We collected 41 lower respiratory specimens from 34 immunocompromised children undergoing evaluation for pulmonary disease at 3 children's hospitals from 2014-2016. Samples underwent mechanical homogenization, parallel RNA/DNA extraction, and metagenomic sequencing. Sequencing reads were aligned to the National Center for Biotechnology Information nucleotide reference database to determine taxonomic identities. Statistical outliers were determined based on abundance within each sample and relative to other samples in the cohort. RESULTS: We identified a rich cross-domain pulmonary microbiome that contained bacteria, fungi, RNA viruses, and DNA viruses in each patient. Potentially pathogenic bacteria were ubiquitous among samples but could be distinguished as possible causes of disease by parsing for outlier organisms. Samples with bacterial outliers had significantly depressed alpha-diversity (median, 0.61; interquartile range [IQR], 0.33-0.72 vs median, 0.96; IQR, 0.94-0.96; P < .001). Potential pathogens were detected in half of samples previously negative by clinical diagnostics, demonstrating increased sensitivity for missed pulmonary pathogens (P < .001). CONCLUSIONS: An optimized mNGS assay for pulmonary microbes demonstrates significant inoculation of the lower airways of immunocompromised children with diverse bacteria, fungi, and viruses. Potential pathogens can be identified based on absolute and relative abundance. Ongoing investigation is needed to determine the pathogenic significance of outlier microbes in the lungs of immunocompromised children with pulmonary disease.

Efficient post-acceleration of protons in helical coil targets driven by sub-ps laser pulses.

The characteristics of laser driven proton beams can be efficiently controlled and optimised by employing a recently developed helical coil technique, which exploits the transient self-charging of solid targets irradiated by intense laser pulses. Here we demonstrate a well collimated (<1° divergence) and narrow bandwidth (~10% energy spread) proton beamlet of ~107 particles at 10 ± 0.5 MeV obtained by irradiating helical coil targets with a few joules, sub-ps laser pulses at an intensity of ~2 × 1019 W cm-2. The experimental data are in good agreement with particle tracing simulations suggesting post-acceleration of protons inside the coil at a rate ~0.7 MeV/mm, which is comparable to the results obtained from a similar coil target irradiated by a fs class laser at an order of magnitude higher intensity, as reported in S. Kar et al., Nat. Commun, 7, 10792 (2016). The dynamics of hot electron escape from the laser irradiated target was studied numerically for these two irradiation regimes, which shows that the target self-charging can be optimised at a pulse duration of few hundreds of fs. This information is highly beneficial for maximising the post-acceleration gradient in future experiments.

Long-Term Pulmonary Function and Quality of Life in Children After Acute Respiratory Distress Syndrome: A Feasibility Investigation.

OBJECTIVES: To determine the feasibility of pulmonary function and quality of life evaluations in children after acute respiratory distress syndrome. DESIGN: A prospective follow-up feasibility study. SETTING: A tertiary PICU. PATIENTS: Children less than 18 years old with acute respiratory distress syndrome admitted between 2000 and 2005. INTERVENTION: Pulmonary function testing and patient and parental quality of life surveys approximately 12-month after acute respiratory distress syndrome. MEASUREMENTS AND MAIN RESULTS: One hundred eighty patients met acute respiratory distress syndrome criteria; 37 (20%) died, 90 (51%) declined participation, 28 (16%) consented but did not return, and 24 (13%) returned for follow-up visit. Twenty-three patients completed quality of life testing and 17 completed pulmonary functions. Clinical characteristics of those who returned were no different from those who did not except for age (median age, 4.9 vs 1.8 yr). One-third had mild to moderate pulmonary function deficits. Quality of life scores were marginal with general health perception, physical functioning, and behavior being areas of concern. These scores were lower than scores in children with chronic asthma. Parental quality of life assessments report lower scores in single-parent homes but no differences were noted by race or parental employment status. CONCLUSIONS: Valuable information may be discerned from acute respiratory distress syndrome patients who return for follow-up evaluation. In this pilot study, up to one-third of children with acute respiratory distress syndrome exhibit pulmonary function deficits and 12-month postillness quality of life scores are lower than in children with chronic asthma. Parental perceptions of postillness quality of life may be negatively impacted by socioeconomic constraints. Long-term follow of children with acute respiratory distress syndrome is feasible and bears further investigation.

A novel method of comparing mating success and survival reveals similar sexual and viability selection for mobility traits in female tree crickets.

The relationship between sexual and viability selection in females is necessarily different than that in males, as investment in sexual traits potentially comes at the expense of both fecundity and survival. Accordingly, females do not usually invest in sexually selected traits. However, direct benefits obtained from mating, such as nuptial gifts, may encourage competition among females and subsidize investment into sexually selected traits. We compared sexual and viability selection on female tree crickets Oecanthus nigricornis, a species where females mate frequently to obtain nuptial gifts and sexual selection on females is likely. If male choice determines female mating success in this species, we expect sexual selection for fecundity traits, as males of many species prefer more fecund females. Alternatively, intrasexual scramble or combat competition on females may select for larger jumping legs or wider heads (respectively). We estimated mating success in wild caught crickets using microsatellite analysis of stored sperm and estimated relative viability by comparing surviving female O. nigricornis to those captured by a common wasp predator. In support of the scramble competition hypothesis, we found sexual selection for females with larger hind legs and narrower heads. We also found stabilizing viability selection for intermediate head width and hind leg size. As predicted, traits under viability and sexual selection were very similar, and the direction of that selection was not opposing. However, because the shape of sexual and viability selection differs, these episodes of selection may favour slightly different trait sizes.

Condition dependence of female choosiness in a field cricket.

Females generally choose mates that produce the loudest, brightest or most elaborate sexual displays, and these costly male displays are predicted to be condition dependent. However, mate choice itself is a costly behaviour also expected to be condition dependent. Male fall field crickets, Gryllus pennsylvanicus, produce a conspicuous long-distance calling song that attracts females and is condition dependent. In this study, we tested the condition dependence of female preferences (preference function and choosiness) for male calling effort in G. pennsylvanicus. We manipulated female condition by raising crickets from hatching on either a low- or high-quality diet. In a series of two-speaker phonotaxis trials, both low- and high-condition females preferred playbacks reflecting greater calling effort. However, relative to low-condition females, high-condition females took significantly longer to make a choice, were more likely to fail to choose within the time allotted for a phonotaxis trial and significantly increased their latency to choose over the course of multiple trials. We discuss these results with respect to the possibility that female G. pennsylvanicus may be foraging for direct benefits when they choose their mates.

Modified Thomson spectrometer design for high energy, multi-species ion sources.

A modification to the standard Thomson parabola spectrometer is discussed, which is designed to measure high energy (tens of MeV/nucleon), broad bandwidth spectra of multi-species ions accelerated by intense laser plasma interactions. It is proposed to implement a pair of extended, trapezoidal shaped electric plates, which will not only resolve ion traces at high energies, but will also retain the lower energy part of the spectrum. While a longer (along the axis of the undeflected ion beam direction) electric plate design provides effective charge state separation at the high energy end of the spectrum, the proposed new trapezoidal shape will enable the low energy ions to reach the detector, which would have been clipped or blocked by simply extending the rectangular plates to enhance the electrostatic deflection.

Stabilizing sexual selection for female ornaments in a dance fly.

Ornamental traits function by improving attractiveness and are generally presumed to experience directional selection for mating success. However, given the greater investment of females in offspring than males, female-specific ornaments can in theory signal fecundity yet be constrained by fecundity costs. Theoretical work predicts that such constraints can lead to stabilizing selection via male choice for intermediately ornamented females. Female dance flies Rhamphomyia longicauda (Diptera: Empididae) display two female-specific ornaments in mating swarms - inflatable abdominal sacs and pinnate tibial scales. We investigated the intensity and form of sexual selection on female traits including ornaments and found no evidence for directional sexual selection. Instead, we found marginally nonsignificant quadratic selection for all three measures of ornament expression. Canonical analysis confirmed that the strongest vectors of nonlinear selection were associated with ornamental traits, although the significance of the quadratic coefficients associated with these vectors depended on the statistical approach. Direct Mitchell-Olds and Shaw tests for the location of the maximum fitted fitness value for both raw morphological traits and canonical axes revealed only one marginally nonsignificant result for the multivariate axis loading most heavily on pinnate leg scales. Together, these results provide the first tentative support for stabilizing selection on female-specific ornaments.

The role of polysomnography in diagnosing and treating obstructive sleep apnea in pediatric patients.

Obstructive sleep apnea in children is associated with serious neurocognitive and cardiovascular morbidity, systemic inflammation, and increased health care use, yet remains underdiagnosed. Although the prevalence of obstructive sleep apnea is 1-3% in the pediatric population, the prevalence of primary snoring (PS) is estimated to be 3-12%. The challenge for pediatricians is to differentiate PS from obstructive sleep apnea in a cost-effective, reliable, and accurate manner before recommending invasive or intrusive therapies, such as surgery or continuous positive airway pressure. The validity of polysomnography as the gold standard for diagnosing obstructive sleep apnea has been challenged, primarily related to concerns that abnormalities on polysomnography do not correlate well with adverse outcomes, that those abnormalities have statistical more than clinical significance, and that performing polysomnograms on all children who snore is a practical impossibility. The aim of this article is to review the clinical utility of diagnostic tests other than polysomnography to diagnose obstructive sleep apnea, to highlight the limitations and strengths of polysomnography, to underscore the threshold levels of abnormalities detected on polysomnography that correlate with morbidity, and to discuss what the practical implications are for treatment.

The evolution of sex differences in mate searching when females benefit: new theory and a comparative test.

Sexual selection is thought to have led to searching as a profitable, but risky way of males obtaining mates. While there is great variation in which sex searches, previous theory has not considered search evolution when both males and females benefit from multiple mating. We present new theory and link it with data to bridge this gap. Two different search protocols exist between species in the bush-cricket genus Poecilimon (Orthoptera): females search for calling males, or males search for calling females. Poecilimon males also transfer a costly nuptial food gift to their mates during mating. We relate variations in searching protocols to variation in nuptial gift size among 32 Poecilimon taxa. As predicted, taxa where females search produce significantly larger nuptial gifts than those where males search. Our model and results show that search roles can reverse when multiple mating brings about sufficiently strong material benefits to females.

Measuring sexual selection on females in sex-role-reversed Mormon crickets (Anabrus simplex, Orthoptera: Tettigoniidae).

Although many studies examine the form of sexual selection in males, studies characterizing this selection in females remain sparse. Sexual selection on females is predicted for sex-role-reversed Mormon crickets, Anabrus simplex, where males are choosy of mates and nutrient-deprived females compete for matings and nutritious nuptial gifts. We used selection analyses to describe the strength and form of sexual selection on female morphology. There was no positive linear sexual selection on the female body size traits predicted to be associated with male preferences and female competition. Instead, we detected selection for decreasing head width and mandible length, with stabilizing selection as the dominant form of nonlinear selection. Additionally, we tested the validity of a commonly used instantaneous measure of mating success by comparing selection results with those determined using cumulative mating rate. The two fitness measures yielded similar patterns of selection, supporting the common sampling method comparing mated and unmated fractions.

Blood product transfusions and clinical outcomes in pediatric patients with acute lung injury.

OBJECTIVE: There are data suggesting that blood product transfusions increase the risk of developing acute lung injury (ALI) in adults, and may be associated with increased mortality in adults with ALI. A possible association between transfusions and adverse outcomes of pediatric patients with ALI has not been studied previously. We tested the hypothesis that blood product transfusions to pediatric patients with ALI within the first 72 hours of the diagnosis would be associated with increased mortality and prolonged mechanical ventilation. DESIGN: An epidemiologic database of pediatric ALI prospectively gathered from July 1996 to May 2000 was analyzed. SETTING: Children were enrolled from both a tertiary referral hospital and a major community children's hospital. PATIENTS: Three hundred fifteen patients who met the 1994 American European Consensus Committee definition of ALI between the ages of 36 weeks corrected gestational age and 18 years. MAIN OUTCOME MEASURE: Mortality in the pediatric intensive care unit. RESULTS: Multivariate analyses indicated that the transfusion of fresh-frozen plasma (FFP) was associated with increased mortality, independent of the severity of hypoxemia (Pao2/Fio2), presence of multiple organ system failure or disseminated intravascular coagulation (odds ratio = 1.08, 95% confidence interval = 1.00-1.17, p = 0.04). FFP transfusion was analyzed as a continuous variable, so that for each milliliter of FFP transfused per kilogram patient body weight per day, the odds of death increased by 1.08. There was a trend toward an association of the transfusion of FFP with a fewer number of days of unassisted ventilation (regression coefficient = -0.21, 95% confidence interval = -0.42-0.01, p = 0.06). CONCLUSIONS: The transfusion of FFP is associated with an increased risk of mortality in children with ALI. The association between FFP and mortality in children with ALI should be investigated further.

Radiotelemetric analysis of the effects of prevailing wind direction on Mormon cricket migratory band movement.

During outbreaks, flightless Mormon crickets [Anabrus simplex Haldeman (Orthoptera: Tettigoniidae)] form large mobile groups known as migratory bands. These bands can contain millions of individuals that march en masse across the landscape. The role of environmental cues in influencing the movement direction of migratory bands is poorly understood and has been the subject of little empirical study. We examined the effect of wind direction on Mormon cricket migratory band movement direction by monitoring the local weather conditions and daily movement patterns of individual insects traveling in bands over the same time course at three close, but spatially distinct sites. Although weather conditions were relatively homogeneous across sites, wind directions tended to be more variable across sites during the morning hours, the period during which directional movement begins. Migratory bands at different sites traveled in distinctly different directions. However, we failed to find any evidence to suggest that the observed variation in migratory band movement direction was correlated with local wind direction at any time during the day. These results support the notion that the cues mediating migratory band directionality are likely to be group specific and that a role for landscape-scale environmental cues such as wind direction is unlikely.

Contrasting sexual selection on males and females in a role-reversed swarming dance fly, Rhamphomyia longicauda Loew (Diptera: Empididae).

Although there are several hypotheses for sex-specific ornamentation, few studies have measured selection in both sexes. We compare sexual selection in male and female dance flies, Rhamphomyia longicauda (Diptera: Empididae). Swarming females display size-enhancing abdominal sacs, enlarged wings and decorated tibiae, and compete for nuptial gifts provided by males. Males preferentially approach large females, but the nature of selection and whether it is sex-specific are unknown. We found contrasting sexual selection for mating success on structures shared by males and females. In females, long wings and short tibiae were favoured, whereas males with short wings and long tibiae had a mating advantage. There was no assortative mating. Females occupying potentially advantageous swarm positions were large and, in contrast to selection for mating success, tended to have larger tibiae than those of rivals. We discuss our findings in the context of both the mating biology of dance flies, and the evolution of sexual dimorphism in general.

Increase in song frequency decreases spermatophore size: correlative evidence of a macroevolutionary trade-off in katydids (Orthoptera: Tettigoniidae).

In many katydids, the male feeds his mate with a large gelatinous spermatophore. Males of most species also produce elaborate calling songs. We predicted a negative relationship between spermatophore size and call frequency because of trade-offs between these two costly traits. Our comparative analysis controlling phylogeny and body size supported this prediction. Although call frequency is expected to decrease with increasing body size, after controlling for phylogeny, both variables were not related. Finally, given that song frequency and spermatophore size are likely targets of sexual selection, we examined the relationship between these variables and sexual size dimorphism (SSD) which can be influenced by sexual selection on body size. We found that only female body size was positively related to SSD, suggesting that natural and/or sexual selection on female body size may be stronger than sexual selection on male and spermatophore size.

Two new Ig VH gene families in Oncorhynchus mykiss.

Genes encoding the immunoglobulin heavy-chain variable region (Ig VH) in rainbow trout (Oncorhynchus mykiss) have been grouped into 11 families. While obtaining a baseline assessment of the various gene families utilized by trout in the production of secreted antibody, we discovered two new families. These proposed Ig VH families, Families XII and XIII, were rarely observed; only two VH sequence types were detected for each new family, suggesting that they may not be commonly used in response to antigens, or that the captive environment may not lead to typical exposures seen in the wild. Additionally, unlike preceding studies, we found at least one representative gene sequence for each of the 11 reported Ig VH gene families, possibly indicating that the repertoire of trout Ig VH gene families may be more universal among different stocks than previously realized.

Higher urine desmosine levels are associated with mortality in patients with acute lung injury.

Desmosine is a stable breakdown product of elastin that can be reliably measured in urine samples. We tested the hypothesis that higher baseline urine desmosine would be associated with higher mortality in 579 of 861 patients included in the recent Acute Respiratory Distress Syndrome Network trial of lower tidal volume ventilation (1). We also correlated urine desmosine levels with indexes of disease severity. Finally, we assessed whether urine desmosine was lower in patients who received lower tidal volumes. Desmosine was measured by radioimmunoassay in urine samples from days 0, 1, and 3 of the study. The data were expressed as a ratio of urine desmosine to urine creatinine to control for renal dilution. The results show that higher baseline (day 0) urine desmosine-to-creatinine concentration was associated with a higher risk of death on adjusted analysis (odds ratio 1.36, 95% confidence interval 1.02-1.82, P=0.03). Urine desmosine increased in both ventilator groups from day 0 to day 3, but the average rise was higher in the 12-ml/kg predicted body weight group compared with the 6-ml/kg predicted body weight group (P=0.053, repeated-measures model). In conclusion, patients with acute lung injury ventilated with lower tidal volumes have lower urine desmosine levels, a finding that may reflect reduced extracellular matrix breakdown. These results illustrate the value of evaluating urinary biological markers that may have prognostic and pathogenetic significance in acute lung injury.