Flipped Quartification: Product Group Unification with Leptoquarks.

The quartification model is an SU(3)4 extension with a bi-fundamental fermion sector of the well-known SU(3)3 bi-fundamentalfication model. An alternative "flipped" version of the quartification model is obtained by rearrangement of the particle assignments. The flipped model has two standard (bi-fundamentalfication) families and one flipped quartification family. In contrast to traditional product group unification models, flipped quartification stands out by featuring leptoquarks and thus allows for new mechanisms to explain the generation of neutrino masses and possible hints of lepton-flavor non-universality.

The Relationship between High Flow Nasal Cannula Flow Rate and Effort of Breathing in Children.

OBJECTIVE: To use an objective metric of effort of breathing to determine optimal high flow nasal cannula (HFNC) flow rates in children <3 years of age. STUDY DESIGN: Single-center prospective trial in a 24-bed pediatric intensive care unit of children <3 years of age on HFNC. We measured the percent change in pressure∙rate product (PRP) (an objective measure of effort of breathing) as a function of weight-indexed flow rates of 0.5, 1.0, 1.5, and 2.0 L/kg/minute. For a subgroup of patients, 2 different HFNC delivery systems (Fisher & Paykel [Auckland, New Zealand] and Vapotherm [Exeter, New Hampshire]) were compared. RESULTS: Twenty-one patients (49 titration episodes) were studied. The most common diagnoses were bronchiolitis and pneumonia. Overall, there was a significant difference in the percent change in PRP from baseline (of 0.5 L/kg/minute) with increasing flow rates for the entire cohort (P < .001) with largest change at 2.0 L/kg/min (-21%). Subgroup analyses showed no significant difference in percent change in PRP from baseline when comparing the 2 different HFNC delivery systems (P = .12). Patients ≤8 kg experienced a larger percent change in PRP as HFNC flow rates were increased (P = .001) than patients >8 kg. CONCLUSIONS: The optimal HFNC flow rate to reduce effort of breathing in infants and young children is approximately 1.5-2.0 L/kg/minute with more benefit seen in children ≤8 kg.

Safety of synchronous prophylactic ablation of the anterior saphenous vein in patients undergoing great saphenous vein thermal ablation- 6 months follow-up data of the SYNCHRONOUS study.

BACKGROUND: The SYNCHRONOUS-study investigates simultaneous ASV-ablation with great saphenous vein (GSV) treatment in endovenous laser ablation (EVLA) for preventing varicose vein recurrence. This sub-study examines complication rates associated with prophylactic ASV-ablation. METHODS: Among 1173 patients with refluxing GSV, 604 underwent GSV-ablation only, and 569 received additional ASV-ablation. Complication rates were compared over 6 months. RESULTS: Approximately 80% of patients were complication-free with minor bruising and dysesthesia being most common complications. After 6 months, additional prophylactic ASV-ablation did not increase the rate of complications compared to GSV-only treatment. CONCLUSION: The 6-months follow-up data suggests that prophylactic ASV-closure, alongside GSV-treatment, is safe, with similar complication rates to GSV-only EVLA.

Compression therapy after endovenous laser ablation: Patient compliance and impact on clinical outcome.

OBJECTIVES: This study aimed to investigate the impact of post-interventional compression therapy on clinical outcomes after endovenous laser ablation (EVLA) of incompetent saphenous veins. METHODS: This prospective, controlled, multicenter study in Germany involved 493 varicose vein patients followed-up for 6 months. RESULTS: Compression therapy significantly reduced symptoms compared to no compression (VCSS: 1.4 ± 1.6 vs 2.2 ± 2.2; p = .007). Post-interventional therapy duration of up to 14 days was found to be most effective for improving patient-reported disease severity (p < .001) and higher quality of life (p = .001). Patient compliance was high (82%), and non-compliance was linked to worse disease severity (VCSS 1.4 ± 1.5 vs 2.1 ± 2.3, p = .009). CONCLUSION: In conclusion, post-interventional compression therapy is beneficial by reducing symptoms and improving quality of life. High patient compliance with the therapy is observed, and non-compliance is associated with worse disease severity.

Impact of a synchronous prophylactic treatment of the anterior accessory saphenous vein on the recurrent varicose vein rate in patients undergoing thermal ablation of an insufficient great saphenous vein (SYNCHRONOUS-Study): study protocol for a prospective, multicentre, controlled observational study.

INTRODUCTION: To date, there are no prospective studies evaluating the prevention of recurrent veins by the simultaneous treatment of a sufficient anterior accessory saphenous vein (AASV) in patients undergoing endovenous laser ablation (EVLA) of an insufficient great saphenous vein (GSV). This study will provide important information about the impact of the AASV on the development of recurrent veins after EVLA of the GSV. Additionally, it will be clarified whether patients benefit from a preventive ablation of a sufficient AASV. METHODS AND ANALYSIS: This is a multicentre, prospective, controlled, exploratory clinical study in 1150 patients with a medical indication for EVLA of a refluxing great saphenous vein. Patients will be enrolled into two study groups: in half of the patients EVLA will be performed on the insufficient GSV only. In the other half of the patients EVLA will be performed on the insufficient GSV and additionally on the sufficient AASV. Within seven study visits, patients will be followed-up over a time period of 5 years. Primary study endpoint is the recurrence rate; secondary endpoints include inter alia, complication rate, postoperative pain intensity, quality of life and patient satisfaction. ETHICS AND DISSEMINATION: Before initiation of the study, the protocol was presented and approved by the independent ethics committee of the medical faculty of the University of Heidelberg (Ethics approval number S-596/2018). This study was prospectively registered at the German Clinical Trial Register (https://www.germanctr.de/). Research findings will be disseminated in a peer-reviewed journal and at relevant conferences. TRIAL REGISTRATION NUMBER: German Clinical Trial Registry (DRKS00015486).

Tackling the Waves of COVID-19: A Planning Model for Intrahospital Resource Allocation.

Background: The current pandemic requires hospitals to ensure care not only for the growing number of COVID-19 patients but also regular patients. Hospital resources must be allocated accordingly. Objective: To provide hospitals with a planning model to optimally allocate resources to intensive care units given a certain incidence of COVID-19 cases. Methods: The analysis included 334 cases from four adjacent counties south-west of Munich. From length of stay and type of ward [general ward (NOR), intensive care unit (ICU)] probabilities of case numbers within a hospital at a certain time point were derived. The epidemiological situation was simulated by the effective reproduction number R, the infection rates in mid-August 2020 in the counties, and the German hospitalization rate. Simulation results are compared with real data from 2nd and 3rd wave (September 2020-May 2021). Results: With R = 2, a hospitalization rate of 17%, mitigation measures implemented on day 9 (i.e., 7-day incidence surpassing 50/100,000), the peak occupancy was reached on day 22 (155.1 beds) for the normal ward and on day 25 (44.9 beds) for the intensive care unit. A higher R led to higher occupancy rates. Simulated number of infections and intensive care unit occupancy was concordant in validation with real data obtained from the 2nd and 3rd waves in Germany. Conclusion: Hospitals could expect a peak occupancy of normal ward and intensive care unit within ~5-11 days after infections reached their peak and critical resources could be allocated accordingly. This delay (in particular for the peak of intensive care unit occupancy) might give options for timely preparation of additional intensive care unit resources.

E-cigarette or Vaping Product Use-Associated Lung Injury Presenting as Sub-Acute Hypoxemia Without Increased Work of Breathing.

A 15-year-old male with a history of mild intermittent asthma presented with fatigue, coughing, vomiting and anorexia which was progressive in nature over the past month. The patient was found to have evolving chest x-ray infiltrates bilaterally, and hypoxemia without accessory muscle use. The patient was placed on non-invasive continuous positive airway pressure (CPAP) for hypoxemia. A CT scan showed bilateral infiltrates in a pattern consistent with E-cigarette or Vaping product use-Associated Lung Injury (EVALI). Upon further history taking, the patient admitted to electronic cigarette (e-cigarette) use with a new tetrahydrocannabinol (THC) cartridge prior to the onset of symptoms. The patient was started on methylprednisolone after which his oxygen requirement improved. This case highlights the need to continue to be diligent regarding the use of e-cigarettes in the pediatric population, and be aware of the constitutional symptoms that are associated with their use.

Risk of Sleepiness-Related Accidents in Switzerland: Results of an Online Sleep Apnea Risk Questionnaire and Awareness Campaigns.

OBJECTIVES: Obstructive sleep apnea syndrome (OSAS) is associated with major morbidity and mortality but OSAS is frequently under recognized. To promote awareness of OSAS, the Swiss Lung League launched an online questionnaire combined with annual advertisements in mass media. Characteristics of participants, prevalence of sleep apnea, OSAS-related symptoms, and their association with accidents were investigated. METHODS: A questionnaire was created incorporating anthropometrics, the Epworth sleepiness scale (ESS), the OSAS domain of the sleep disorders questionnaire (SDQ), and a question on accidents related to sleepiness. RESULTS: A total of 198,422 persons participated, 63% were male, mean (±SD) age was 45 (±16) years, weight 80 (±18) kg, height 173 (±9) cm, and body mass index 26.7 (±5.4) kg/m2. Some male (19%) and female (17%) participants had both elevated ESS and SAS scores (SAS > 35 (m)/SAS > 31 (f) and ESS > 10) and were suspected of having sleep apnea. In all, 6,654 (3.4%) had suffered an accident related to sleepiness. In multivariate regression analysis, ESS item #8 (falling asleep on the wheel, while stopping for a few minutes in traffic) was closest related to suffering an accident (OR 2.8). CONCLUSION: The OSAS awareness campaign of the Swiss Lung League reached a large number of people of both genders and of a wide age range. Many participants suffered from excessive sleepiness and symptoms of sleep apnea were highly prevalent. The campaign raised awareness of OSAS and contributed to the diagnosis and treatment of sleep apnea, thereby possibly preventing related morbidity and mortality.

Racial differences in the clinical presentation of pediatric eosinophilic esophagitis.

BACKGROUND: Analysis of current data suggests that 80% to 90% of children diagnosed with eosinophilic esophagitis are white. Little data exist regarding the presentation of eosinophilic esophagitis and potential clinical differences in minority children. OBJECTIVE: This study compared the clinical presentation of eosinophilic esophagitis in African American children with white children treated at an urban allergy referral center. METHODS: At an urban allergy clinic, a 2-year retrospective chart review was performed of 50 consecutive pediatric patients diagnosed with eosinophilic esophagitis. Presenting symptoms, age at diagnosis, coexisting atopic disease, and laboratory parameters were compared between races. RESULTS: Most of the 50 children identified were boys (74%), as previously described. However, unlike prior literature, most were nonwhite (42% white, 42% African American, 4% Asian, and 12% other). African American children compared with white children had (1) a significantly higher frequency of failure to thrive (P < .01) and vomiting (P < .01) as presenting symptoms, (2) a higher frequency of comorbid atopic dermatitis (P < .01), (3) a younger mean age of symptom presentation and formal diagnosis (3.7 vs 9.1 years; P < .01), and (4) a trend toward a longer interval between symptom onset and formal diagnosis. However, after adjusting for confounding variables of age and insurance type, several of these racial differences were no longer significant. CONCLUSION: African American children in this series had a larger burden of eosinophilic esophagitis than previously described as well as differences in clinical presentation compared with white patients. Analysis of these findings suggests that providers be aware of this potential diagnosis in young, atopic African American children with symptoms of esophageal dysfunction.

Novel finding of coronary ectasia in a case of acute rheumatic Fever.

A 10-year-old boy presented to his pediatrician with acute fever, rash, and polyarthritis. Laboratory studies revealed elevated inflammatory markers and positive throat culture. Echocardiogram demonstrated panvalvular insufficiency consistent with acute rheumatic fever (ARF) and coronary artery ectasia. This latter finding, typically associated with Kawasaki disease, has not been previously reported in ARF.

Unitary parametrization of perturbations to tribimaximal neutrino mixing.

Current experimental data on neutrino mixing are very well described by tribimaximal mixing. Accordingly, any phenomenological parametrization of the Maki-Nakagawa-Sakata-Pontecorvo matrix must build upon tribimaximal mixing. We propose one particularly natural parametrization, which we call "triminimal." The three small deviations of the Particle Data Group angles from their tribimaximal values, and the PDG phase, parametrize the triminimal mixing matrix. As an important example of the utility of this new parametrization, we present the simple resulting expressions for the flavor-mixing probabilities of atmospheric and astrophysical neutrinos. As no foreseeable experiment will be sensitive to more than second order in the small parameters, we expand these flavor probabilities to second order.

TeV gamma rays from photodisintegration and daughter deexcitation of cosmic-ray nuclei.

It is commonly assumed that high-energy gamma rays are made via either purely electromagnetic processes or the hadronic process of pion production, followed by decay. We investigate astrophysical contexts where a third process (A*) would dominate: namely, the photodisintegration of highly boosted nuclei followed by daughter deexcitation. Starburst regions such as Cygnus OB2 appear to be promising sites for TeV gamma-ray emission via this mechanism. A unique feature of the A* process is a sharp flattening of the energy spectrum below approximately 10 TeV/(T/eV) for gamma-ray emission from a thermal region of temperature T. The A* mechanism described herein offers an important contribution to gamma-ray astronomy in the era of intense observational activity.

Neutrino cross sections and future observations of ultrahigh-energy cosmic rays.

We show that future detectors of ultrahigh-energy cosmic-ray neutrinos will be able to measure neutrino-nucleon cross section, sigma(nu N), at energies as high as 10(11) GeV or higher. We find that the flux of upgoing charged leptons per unit surface area produced by neutrino interactions below the surface is inversely proportional to sigma(nu N). This contrasts with the rate of horizontal air showers (HAS) due to neutrino interactions in the atmosphere, which is proportional to sigma(nu N). Thus, by comparing the HAS and upgoing air shower rates, the neutrino-nucleon cross section can be inferred. Taken together, upgoing and horizontal rates ensure a healthy total event rate, regardless of the value of sigma(nu N).

Decay of high-energy astrophysical neutrinos.

Existing limits on the nonradiative decay of one neutrino to another plus a massless particle (e.g., a singlet Majoron) are very weak. The best limits on the lifetime to mass ratio come from solar neutrino observations and are tau/m greater, similar 10(-4) s/eV for the relevant mass eigenstate(s). For lifetimes even several orders of magnitude longer, high-energy neutrinos from distant astrophysical sources would decay. This would strongly alter the flavor ratios from the phi(nu(e)):phi(nu(mu)):phi(nu(tau))=1:1:1 expected from oscillations alone and should be readily visible in the near future in detectors such as IceCube.

Pseudo-dirac neutrinos: a challenge for neutrino telescopes.

Neutrinos may be pseudo-Dirac states, such that each generation is actually composed of two maximally mixed Majorana neutrinos separated by a tiny mass difference. The usual active neutrino oscillation phenomenology would be unaltered if the pseudo-Dirac splittings are deltam(2) less, similar 10(-12) eV(2); in addition, neutrinoless double beta decay would be highly suppressed. However, it may be possible to distinguish pseudo-Dirac from Dirac neutrinos using high-energy astrophysical neutrinos. By measuring flavor ratios as a function of L/E, mass-squared differences down to deltam(2) approximately 10(-18) eV(2) can be reached. We comment on the possibility of probing cosmological parameters with neutrinos.