Short-time mentoring - enhancing female medical students' intentions toward surgical careers

BACKGROUND

Women pursuing a career in surgery or related disciplines are still in the minority, despite the fact that women compose at least half of the medical student population in most Western countries. Thus, recruiting and retaining female surgeons remains an important challenge to meet the need for surgeons and increase the quality of care. The participations were female medical students between their third and fifth academic year. In this study, we applied the well-established psychological theory of planned behavior (TPB) which suggests that the intention to perform a behavior (e.g. pursuing a career in surgery) is the most critical and immediate predictor of performing the behavior. We investigated whether a two-part short-mentoring seminar significantly increases students' intention to pursue a career in a surgical or related specialty after graduation.

METHOD

The mentoring and role-model seminar was conducted at 2 days for 90 minutes by six inspiring female role models with a remarkable career in surgical or related disciplines. Participants (N = 57) filled in an online survey before (T0) and after the seminar (T1). A pre-post comparison of central TPB concept attitude towards the behavior, 2) occupational self-efficacy and 3) social norm) was conducted using a paired sampled t-test. A follow-up survey was administered 12 months later (T2).

RESULTS

The mentoring seminar positively impacted female students' attitude towards a career in a surgical specialty. Female students reported a significantly increased positive attitude (p < .001) and significantly higher self-efficacy expectations (p < .001) towards a surgical career after participating in the mentoring seminar. Regarding their career intention after the seminar, female students declared a significantly higher intention to pursue a career in a surgical specialty after graduating (p < .001) and this effect seems to be sustainable after 1 year.

CONCLUSION

For the first time we could show that short-mentoring and demonstrating role models in a seminar surrounding has a significant impact on female medical student decision´s to pursue a career in a surgery speciality. This concept may be a practical and efficient concept to refine the gender disparity in surgery and related disciplines.

[Nuclear medicine procedure guideline for sentinel lymph node localization]

The authors present a procedure guideline for scintigraphic detection of sentinel lymph nodes in malignant melanoma, in breast cancer, in penile and vulva tumors, in head and neck cancer, and in prostate carcinoma. Important goals of sentinel lymph node scintigraphy comprise reduction of the extent of surgery, lower postoperative morbidity and optimization of histopathological examination focussing on relevant lymph nodes. Sentinel lymph node scintigraphy itself does not diagnose tumorous lymph node involvement and is not indicated when lymph node or distant metastases have been definitely diagnosed before sentinel lymph node scintigraphy. Procedures are compiled with the aim to reliably localise sentinel lymph nodes with a high detection rate typically in early tumour stages. New aspects in this guideline are new radiopharmaceuticals such as tilmanocept and Tc-99m-PSMA and SPECT/CT allowing an easier anatomical orientation. Initial dynamic lymphoscintigraphy in breast cancer is of little significance nowadays. Radiation exposure is low so that pregnancy is not a contraindication for sentinel lymph node scintigraphy. A one-day protocol should preferentially be used. Even with high volumes of scintigraphic sentinel lymph node procedures surgeons, theatre staff and pathologists receive a radiation exposure < 1 mSv/year so that they do not require occupational radiation surveillance. Aspects of quality control were included (scintigraphy, quality control of gamma probe, 6 h SLN course for surgeons, certified breast centers, medical surveillance center).

Spectroscopic investigation of size-dependent CO2 binding on cationic copper clusters: analysis of the CO2 asymmetric stretch

Photofragmentation spectroscopy, combined with quantum chemical computations, was employed to investigate the position of the asymmetric CO2 stretch in cold, He-tagged Cun[CO2]+ (n = 1-10) and Cun[CO2][H2O]+ (n = 1-7) complexes. A blue shift in the band position was observed compared to the free CO2 molecule for Cun[CO2]+ complexes. Furthermore, this shift was found to exhibit a notable dependence on cluster size, progressively redshifting with increasing cluster size. The computations revealed that the CO2 binding energy is the highest for Cu+ and continuously decreases with increasing cluster size. This dependency could be explained by highlighting the role of polarization in electronic structure, according to energy decomposition analysis. The introduction of water to this complex amplified the redshift of the asymmetric stretch, showing a similar dependency on the cluster size as observed for Cun[CO2]+ complexes.

Observation of Medium-Induced Yield Enhancement and Acoplanarity Broadening of Low-p_{T} Jets from Measurements in pp and Central Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The ALICE Collaboration reports the measurement of semi-inclusive distributions of charged-particle jets recoiling from a high transverse momentum (high p_{T}) hadron trigger in proton-proton and central Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV. A data-driven statistical method is used to mitigate the large uncorrelated background in central Pb-Pb collisions. Recoil jet distributions are reported for jet resolution parameter R=0.2, 0.4, and 0.5 in the range 7 Collapse

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Role of the Binding Energy on Nondipole Effects in Single-Photon Ionization

We experimentally study the influence of the binding energy on nondipole effects in K-shell single-photon ionization of atoms at high photon energies. We find that for each ionization event, as expected by momentum conservation, the photon momentum is transferred almost fully to the recoiling ion. The momentum distribution of the electrons becomes asymmetrically deformed along the photon propagation direction with a mean value of 8/(5c)(E_{γ}-I_{P}) confirming an almost 100 year old prediction by Sommerfeld and Schur [Ann. Phys. (N.Y.) 396, 409 (1930)10.1002/andp.19303960402]. The emission direction of the photoions results from competition between the forward-directed photon momentum and the backward-directed recoil imparted by the photoelectron. Which of the two counteracting effects prevails depends on the binding energy of the emitted electron. As an example, we show that at 20 keV photon energy, Ne^{+} and Ar^{+} photoions are pushed backward towards the radiation source, while Kr^{+} photoions are emitted forward along the light propagation direction.

Emergence of Long-Range Angular Correlations in Low-Multiplicity Proton-Proton Collisions

This Letter presents the measurement of near-side associated per-trigger yields, denoted ridge yields, from the analysis of angular correlations of charged hadrons in proton-proton collisions at sqrt[s]=13  TeV. Long-range ridge yields are extracted for pairs of charged particles with a pseudorapidity difference of 1.4<|Δη|<1.8 and a transverse momentum of 1 Collapse

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First Measurement of the |t| Dependence of Incoherent J/ψ Photonuclear Production

The first measurement of the cross section for incoherent photonuclear production of J/ψ vector mesons as a function of the Mandelstam |t| variable is presented. The measurement was carried out with the ALICE detector at midrapidity, |y|<0.8, using ultraperipheral collisions of Pb nuclei at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV. This rapidity interval corresponds to a Bjorken-x range (0.3-1.4)×10^{-3}. Cross sections are given in five |t| intervals in the range 0.04<|t|<1  GeV^{2} and compared to the predictions by different models. Models that ignore quantum fluctuations of the gluon density in the colliding hadron predict a |t| dependence of the cross section much steeper than in data. The inclusion of such fluctuations in the same models provides a better description of the data.

[Guideline for Radioiodine Therapy for Benign Thyroid Diseases (6/2022 - AWMF No. 031-003)]

This version of the guideline for radioiodine therapy of benign thyroid disorders is an update of the version, which was published by the German Society of Nuclear Medicine (Deutsche Gesellschaft für Nuklearmedizin, DGN) in co-ordination with the German Society of Endocrinology (Deutsche Gesellschaft für Endokrinologie, DGE, Sektion Schilddrüse) and the German Society of General- and Visceral-Surgery (Deutsche Gesellschaft für Allgemein- und Viszeralchirurgie, DGAV) in 2015. This guideline was harmonized with the recommendations of the European Association of Nuclear Medicine (EANM). According to the German "Directive on Radiation Protection in Medicine" the physician specialised in nuclear medicine ("Fachkunde in der Therapie mit offenen radioaktiven Stoffen") is responsible for the justification to treat with radioiodine. Therefore, relevant medical indications for radioiodine therapy and alternative therapeutic options are discussed within the guideline. This procedure guideline is developed in the consensus of an expert group. This fulfils the level S1 (first step) within the German classification of Clinical Practice Guidelines.

ψ(2S) Suppression in Pb-Pb Collisions at the LHC

The production of the ψ(2S) charmonium state was measured with ALICE in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV, in the dimuon decay channel. A significant signal was observed for the first time at LHC energies down to zero transverse momentum, at forward rapidity (2.5 Collapse

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Effects of third-neighbor interactions on the frustrated quantum Ising model

We investigate thermal and quantum phase transitions of the J_{1}-J_{2}-J_{3} transverse Ising model on the square lattice. The model is studied within a cluster mean-field decoupling, which allows us to describe phase diagrams and the free-energy landscape in the neighborhood of phase transitions. Our findings indicate that the third-neighbor coupling (J_{3}) can affect the nature of phase transitions of the model. In particular, ferromagnetic third-neighbor couplings favor the onset of continuous order-disorder phase transitions, eliminating the tricritical point of the superantiferromagnetic-paramagnetic (SAFM-PM) phase boundary. On the other hand, the enhancement of frustration introduced by weak antiferromagnetic J_{3} gives rise to the staggered dimer phase favoring the onset of discontinuous classical phase transitions. Moreover, we find that quantum annealed criticality (QAC), which takes place when the classical discontinuous phase transition becomes critical by the enhancement of quantum fluctuations introduced by the transverse magnetic field, is eliminated from the SAFM-PM phase boundary by a relatively weak ferromagnetic J_{3}. Nevertheless, this change in the nature of phase transitions can still be observed in the presence of antiferromagnetic third-neighbor couplings being also found in the staggered-dimer phase boundary. Therefore, our findings support that QAC persists under the presence of frustrated antiferromagnetic third-neighbor couplings and is suppressed when these couplings are ferromagnetic, suggesting that frustration plays a central role in the onset of QAC.

Comparisons between young adult waterpipe smokers and nonsmokers' reactions to pictorial health warning labels in Lebanon: a randomized crossover experimental study

This study compares the impact of pictorial health warning labels (HWLs) and their placements on waterpipe parts (device, tobacco and charcoal packages) on health communication outcomes between waterpipe smokers and nonsmokers in Lebanon. An online randomized crossover experimental study was conducted among young adults (n = 403, August 2021) who observed three conditions of HWLs: pictorial HWLs on the tobacco package, pictorial HWLs on all waterpipe's parts and text-only HWL on the tobacco package in random order. Participants completed post-exposure assessments of health communication outcomes after each image. Using linear mixed models, we examined the differences in the effect of HWL conditions on several outcomes (i.e. warning reactions) between waterpipe smokers and nonsmokers, controlling for confounders (i.e. age, sex). Nonsmokers reported greater attention (β = 0.54 [95% confidence interval: 0.25-0.82]), cognitive elaboration (0.31 [0.05-0.58]) and social interaction (0.41 [0.18-0.65]) for pictorial HWLs on the tobacco packages than text-only compared with smokers. Pictorial HWLs on three parts versus one part elicited higher cognitive reactions and perceived message effectiveness in nonsmokers compared with waterpipe smokers. These findings provide valuable information for policymakers about the potential of implementing HWLs specific to waterpipes to prevent their use among young adults and limit tobacco-related morbidity and mortality in Lebanon.

Measurements of Groomed-Jet Substructure of Charm Jets Tagged by D^{0} Mesons in Proton-Proton Collisions at sqrt[s]=13 TeV

Understanding the role of parton mass and Casimir color factors in the quantum chromodynamics parton shower represents an important step in characterizing the emission properties of heavy quarks. Recent experimental advances in jet substructure techniques have provided the opportunity to isolate and characterize gluon emissions from heavy quarks. In this Letter, the first direct experimental constraint on the charm-quark splitting function is presented, obtained via the measurement of the groomed shared momentum fraction of the first splitting in charm jets, tagged by a reconstructed D^{0} meson. The measurement is made in proton-proton collisions at sqrt[s]=13  TeV, in the low jet transverse-momentum interval of 15≤p_{T}^{jet ch}<30  GeV/c where the emission properties are sensitive to parton mass effects. In addition, the opening angle of the first perturbative emission of the charm quark, as well as the number of perturbative emissions it undergoes, is reported. Comparisons to measurements of an inclusive-jet sample show a steeper splitting function for charm quarks compared with gluons and light quarks. Charm quarks also undergo fewer perturbative emissions in the parton shower, with a reduced probability of large-angle emissions.

Bridging the Gap of Radiotherapy Treatment Planning Quality between High-Income, and Low- and Middle-Income Countries Using Knowledge-Based Planning

PURPOSE/OBJECTIVE(S)

Radiotherapy departments in low- and middle-income countries (LMICs) like Guatemala have recently introduced intensity-modulated radiotherapy (IMRT). IMRT has become the standard of care in high-income countries (HIC) due to reduced toxicity and improved outcomes in some cancers. The purpose of this work is to show the feasibility of adapting knowledge-based (KB) models established in a HIC to a LMIC lacking experience in IMRT to improve plan quality and planning efficiency.

MATERIALS/METHODS

A Halcyon Linac was installed at our clinic in Guatemala in 2019 and has been used to treat approximately 90 patients daily with IMRT. A model developed on a cohort of head and neck cancer patients at a US academic radiotherapy center were applied at our center to create 20head and neck VMAT plans with different prescriptions, including simultaneous-integrated and sequential boosts.

RESULTS

The plans created using the KB models achieved similar coverage of the planning target volume for each plan KB plans showed better 1) Parotid sparing with a mean dose reduction between 5%-25% and spinal cord maximum dose reduction between 3%-15%. The time efficiency to create VMAT plans using KB model versus manual planning improved four-fold, on average one hour versus more than 4 hours, respectively.

CONCLUSION

Despite different prescriptions, guidelines and demographics of cancer patients between two institutions in a HIC and LMIC, this work demonstrates that KB planning can be used to generate better and more consistent VMAT plans versus manually created plans. In addition, KB planning has the potential to greatly increase planning efficiency higher efficiency and help address the shortage of medical physicists and dosimetrists in LMICs.

Standardizing LT Chest Wall Radiotherapy Treatment Planning in a Low- or Middle- Income Country Radiotherapy Clinic Using Knowledge Based Planning

PURPOSE/OBJECTIVE(S)

Radiotherapy departments in low- or middle-income countries (LMICs) tend to lag behind introducing emerging technologies like intensity-modulated radiotherapy (IMRT). IMRT has become the standard of care in high-income countries (HIC) due to reduced toxicity and improved outcomes in a wide variety of cancers. The purpose of this work is showing the results of left Chest-Wall knowledge-based planning (KBP) standardization and implementation in a LMIC setting.

MATERIALS/METHODS

A Halcyon Linac was installed at our clinic in Guatemala in 2019 and currently used to treat ∼90 IMRT patients daily. The standardization of IMRT procedures has been difficult for complex sites like chest-wall. The steps for standardization included: AAPM TG-263 nomenclature implementation, and planning workflows within the TPS, creation of optimization structures, and plan quality evaluation following RTOG1005 protocol hypofractionation arm. 25 plans were created manually achieving all RTOG1005 protocol constraints. The statistics were analyzed trough the model analytics tool provided by KPB manufacturer.

RESULTS

The results show that more plans are needed to improve the KBP model. This initial model was used to create a standardized clinical protocol in the TPS in order to continue adding plans to the KBP model database. This approach ensures that we obtain consistent plan quality and standardize our planning. The manual planning objectives achieved: CONCLUSION: The experience using the TPS to standardize our treatment planning process achieved good consistency in our planning objectives. This approach will help create KBP models according to our own clinic-specific requirements. Future work will be made to compare our LMIC KBP models with those made at a HIC academic radiotherapy center.

Temporospatial Feathering of Hot Spots for Computed Tomography-Guided Stereotactic Adaptive Radiotherapy (CT-STAR) for the Ultra-Central Thorax

PURPOSE/OBJECTIVE(S)

SBRT to the ultra-central thorax is limited by potential toxicity. It has been demonstrated that exposing proximal bronchial tree or pulmonary arteries to high dose per fraction (fx) treatment may induce bronchopulmonary hemorrhage, amongst other serious complications. Online adaptive radiotherapy is a technique that adjusts a treatment plan to the anatomy-of-the-day and benefits have been demonstrated in ultra-central thoracic disease. In addition, feathering is a treatment planning technique that generates several plans to avoid consistent organ-at-risk (OAR) doses throughout treatment. With daily adaptation, it may be possible to adjust the position of a hot spot (>120% prescription (Rx)) within the tumor each fx (temporospatial feathering) while respecting hard OAR constraints. We investigated the feasibility and plan quality of using CBCT-guided stereotactic adaptive radiotherapy (CT-STAR) for ultra-central lung tumors with hotspot temporospatial feathering.

MATERIALS/METHODS

Seven patients with ultra-central thoracic disease (6 patients with parenchymal tumors in contact with the trachea, proximal bronchial tree, great vessels, esophagus, or heart; 1 patient with a subcarinal lymph node) receiving standard of care radiotherapy were enrolled on an imaging study. An in-silico planning study first generated an SBRT plan (in silico Rx: 55 Gy in 5fx) that used a GTV_OPT (GTV minus OAR plus a safety margin) to optimize the location of the plan hotspot. Five spherical boost structures were manually created inside of the GTV_OPT structure. The same planning template was used except the boost structures were iteratively used in plan optimization instead of the GTV_OPT structure, to simulate the five CT-STAR fx hotspot temporospatially feathering. The five-plan composite was compared to the initial plan.

RESULTS

All plans generated met strict OAR constraints. Table 1 shows the mean difference in PTV, GTV, and OARs percent coverage by various isodose levels. Feathering the hotspot had negligible impact on target coverage by 50 Gy and 55 Gy isodose lines as well as OAR doses compared to the base SBRT plan. The feathered plan sum resulted in 14.7% increase in V66 Gy of the GTV. One patient saw a decrease in V66 Gy coverage to all target structures, though V50 Gy and V55 Gy were not affected.

CONCLUSION

We demonstrated the feasibility and utility of temporospatially adapting the hotspot for central lung SBRT, which safely increases the amount of tumor receiving more than 120% Rx.

Initial Experience with the Commercial Electron FLASH Research Extension

PURPOSE/OBJECTIVE(S)

The purpose of this study was to introduce a new commercial electron FLASH system that has the potential to become widely available for FLASH researchers globally. In this study, we first present the initial acceptance and commissioning tests for the FLASH system, and second, we highlight preliminary FLASH effect results from our cell studies.

MATERIALS/METHODS

A linear accelerator was converted into a commercial research platform with the FLASH Research Extension, enabling the generation of a powerful 16 MeV electron FLASH beam. The dosimetric and stability tests were conducted using various dosimeters (i.e., radiochromic film, optically stimulated luminescent dosimeters (OSLDs), and a plane-parallel ionization chamber). To evaluate the FLASH effect, normal and cancer cell lines were FLASH irradiated using different pulse repetition frequencies (PRF) of 18 pulses/s and 180 pulses/s.

RESULTS

The electron FLASH mode was able to generate over 1 Gy per pulse at the isocenter and a dose rate of up to 690 Gy/s near the accessory mount of the Linac gantry head. The charge collected by the plane-parallel ionization chamber at the highest PRF (i.e., 180 pulses/s) showed a linear relationship with the delivered number of pulses (i.e., 1 to 99 pulses) with a coefficient of determination (R2) of 0.9996. The absorbed dose measured using radiochromic film and OSLDs agreed within 3%, on average, and followed an inverse square law as the source-to-axis distance (SAD) varied for which the R2 values were 0.9972 and 0.9955 for radiochromic film and OSLDs, respectively. The profile of the FLASH beam was symmetrical but was not as flat as the conventional 16 MeV electron beam due to the use of a thinner custom scattering foil to reduce the degradation of the ultra-high dose rate. The depth-dose curve beyond the build-up region for the FLASH beam was similar to the conventional 16 MeV electron beam for which the range at 50% the maximum dose (R50) agreed within 0.5 mm. The FLASH beam output remained consistent over a 4-month period with a variation of 2.5%, on average. The FLASH sparing effect was observed in vitro for healthy human pancreatic cells. Furthermore, we observed that the highest PRF beam (180 pulses/s) was more effective at destroying pancreatic cancerous cells while minimizing damage to healthy cells compared to the lowest PRF beam (18 pulses/s).

CONCLUSION

The novel commercial FLASH Research Extension system was dosimetrically characterized for pre-clinical FLASH research, and preliminary in vitro results demonstrated the FLASH effect. Given the prevalence of linear accelerators, this new commercial system has the potential to greatly increase the access to FLASH research.

Effect of Dose to the Heart and Cardiac Substructures on Cardiac Toxicity after Breast Cancer Radiation

PURPOSE/OBJECTIVE(S)

Pre-existing cardiovascular disease, chemotherapy, and higher mean heart dose are known risk factors for cardiac toxicity after breast radiation therapy. However, the relationship between cardiac substructure radiation exposure and toxicity is not well understood. We hypothesized that mean heart dose is a surrogate for global cardiac radiation exposure but that more specific dosimetric thresholds for the heart and its substructures could be identified, which could be used to guide radiation planning for breast cancer patients in the future.

MATERIALS/METHODS

In this cohort study, all breast cancer patients who received curative intent breast or chest wall radiotherapy at a single high-volume institution in 2014 and 2017 were included (n = 841). Baseline characteristics included hormone therapy, chemotherapy, menopausal status, diabetes, dyslipidemia, pre-existing cardiac toxicity, and age at diagnosis. Outcomes included any cardiac toxicity, arrhythmia, cardiomyopathy, ischemia, valvular, pericardial disease, and death. The heart and substructures, including left ventricle, right ventricle, left atrium, right atrium, aortic valve, pulmonic valve, mitral valve, tricuspid valve, and left anterior descending artery, were delineated on the simulation CT for each patient. Dosimetric variables, including mean dose, max dose, and V1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, and 70 Gy for the heart and substructures (in cc) were extracted. For each dosimetric variable, multivariable logistic regression was performed using baseline covariates in addition to the single dosimetric variable. Patients with missing data values were excluded. Results were combined and False Discovery Rate p-value correction was performed.

RESULTS

Multiple cardiac substructure dosimetric variables were associated with increased risk of mortality on multivariable analysis (p < 0.05). For left atrium and right atrium, V2, 3, 4, and 5 Gy were all significant. For right ventricle, mean dose, V1, 2, 3, 4, 5, 10, 15, 20, 25, 30, and 35 Gy were significant. For mitral valve, mean dose, max dose, V3, 4, and 5 Gy were significant. For tricuspid valve, mean dose was significant. For aortic valve, max dose, mean dose, V4, and V5 Gy were significant. For the whole heart, V1, 2, 3, 4, 5, 10, 15, 20, 25, 30, and 35 Gy were significant.

CONCLUSION

We have identified multiple dosimetric variables for the heart and its substructures which were associated with increased risk of mortality after breast cancer radiation. In fact, for certain structures, there were multiple exposure thresholds which showed increased risk of toxicity, highlighting the complex relationship between substructure dose and outcomes. Further study into these relationships will identify the most critical cardiac substructure constraints that could be used in radiation treatment planning.

Commissioning and Initial Validation of Commercial Treatment Planning System for the Electron FLASH Research Extension

PURPOSE/OBJECTIVE(S)

The aim of this study was to investigate the feasibility of commissioning the 16 MeV electron FLASH beam in a commercial treatment planning system (TPS) for pre-clinical research purposes. The delivery system consisted of a new commercial solution for which a linear accelerator was modified into a FLASH Research Extension platform. Additionally, preliminary radiation biology results were highlighted to showcase the future use of this system.

MATERIALS/METHODS

To commission a commercial electron Monte Carlo (MC) for dose calculation of a 16 MeV FLASH beam in the TPS, radiochromic film was used to measure the vendor-required beam data, e.g., profiles and percent depth dose (PDD) curves for cone sizes of 6 × 6 cm2, 10 × 10 cm2, and 15 × 15 cm2 as well as an in-air profile for a 40 × 40 cm2 open field (no cone). Once the electron MC beam model was generated, additional measurements were collected for validation and compared against the calculated dose from the TPS. A treatment planning comparison between the newly commissioned FLASH beam and the conventional electron beam was conducted. Specifically, the dose-volume histograms (DVHs) for target volumes and organs at risk were investigated for skin cancer cases previously treated with conventional electron beams. Lastly, the FLASH dose distribution predicted by the electron MC for an in vitro cell study setup was validated with radiochromic film measurements, and initial radiobiology tests were conducted using FLASH and conventional dose-rate electron beams.

RESULTS

The electron MC calculated dose for the 16 MeV electron FLASH beam agreed with measured PDDs within 1% for all field sizes. The beam profile characteristics, such as penumbra, shape, and full width at half maximum, demonstrated good agreement with less than 0.5 mm difference between the TPS and measurements. There were noticeable differences in the profiles of large fields between the FLASH and conventional dose-rate beam models due to the more forward-peaked FLASH beam. For treatment planning, Regarding DVH, the FLASH dose-rate plan provided comparable plan quality to the conventional dose-rate plan, achieving adequate coverage for the target volumes and sparing the healthy organs and tissues. The electron MC dose prediction for the FLASH beam was also found to be in good agreement with the film measurements of the in vitro cell study setup. Furthermore, the FLASH beam was observed to be more effective with a 20 % increase in killing pancreatic cancer cells compared to the conventional dose rate.

CONCLUSION

The study successfully incorporated the 16 MeV electron FLASH Research Extension into the commercial TPS using electron Monte Carlo for dose calculation. This will be valuable for pre-clinical cell and animal studies. This research also enables FLASH treatment planning studies, a key component for the future implementation of FLASH into clinical care. Further research is necessary to incorporate the radiation biology effect of FLASH into the treatment planning system.

Measurement of the Lifetime and Λ Separation Energy of _{Λ}^{3}H

The most precise measurements to date of the _{Λ}^{3}H lifetime τ and Λ separation energy B_{Λ} are obtained using the data sample of Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV collected by ALICE at the LHC. The _{Λ}^{3}H is reconstructed via its charged two-body mesonic decay channel (_{Λ}^{3}H→^{3}He+π^{-} and the charge-conjugate process). The measured values τ=[253±11(stat)±6(syst)]  ps and B_{Λ}=[102±63(stat)±67(syst)]  keV are compatible with predictions from effective field theories and confirm that the _{Λ}^{3}H structure is consistent with a weakly bound system.

Is the process of withdrawal of life-sustaining measures in the intensive care unit different for deceased organ donors compared with other dying patients? A secondary analysis of prospectively collected data

OBJECTIVE

To investigate whether observable differences exist between patterns of withdrawal of life-sustaining measures (WLSM) for patients eligible for donation after circulatory death (DCD) in whom donation was attempted compared with those patients in whom no donation attempts were made.

SETTING

Adult intensive care units from 20 centres in Canada, the Czech Republic and the Netherlands.

DESIGN

Secondary analysis of quantitative data collected as part of a large, prospective, cohort study (the Death Prediction and Physiology after Removal of Therapy study).

PARTICIPANTS

Patients ≥18 years of age who died after a controlled WLSM in an intensive care unit. Patients were classified as not DCD eligible, DCD eligible with DCD attempted or DCD eligible but DCD was not attempted.

PRIMARY AND SECONDARY OUTCOME MEASURES

The process of WLSM (timing and type and, if applicable, dosages of measures withdrawn, dosages of analgesics/sedatives) was compared between groups.

RESULTS

Of the 635 patients analysed, 85% had either cardiovascular support stopped or were extubated immediately on WLSM. Of the DCD eligible patients, more were immediately extubated at the initiation of WLSM when DCD was attempted compared with when DCD was not attempted (95% vs 61%, p<0.0001). Initiation of WLSM with the immediate cessation of cardiovascular measures or early extubation was associated with earlier time to death, even after adjusting for confounders (OR 2.94, 95% CI 1.39 to 6.23, at 30 min). Other than in a few patients who received propofol, analgesic and sedative dosing after WLSM between DCD attempted and DCD eligible but not attempted patients was not significantly different. All patients died.

CONCLUSIONS

Patients in whom DCD is attempted may receive a different process of WLSM. This highlights the need for a standardised and transparent process for end-of-life care across the spectrum of critically ill patients and potential organ donors.

Measurement of the J/ψ Polarization with Respect to the Event Plane in Pb-Pb Collisions at the LHC

We study the polarization of inclusive J/ψ produced in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV at the LHC in the dimuon channel, via the measurement of the angular distribution of its decay products. We perform the study in the rapidity region 2.5 Collapse

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First Measurement of Antideuteron Number Fluctuations at Energies Available at the Large Hadron Collider

The first measurement of event-by-event antideuteron number fluctuations in high energy heavy-ion collisions is presented. The measurements are carried out at midrapidity (|η|<0.8) as a function of collision centrality in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV using the ALICE detector. A significant negative correlation between the produced antiprotons and antideuterons is observed in all collision centralities. The results are compared with a state-of-the-art coalescence calculation. While it describes the ratio of higher order cumulants of the antideuteron multiplicity distribution, it fails to describe quantitatively the magnitude of the correlation between antiproton and antideuteron production. On the other hand, thermal-statistical model calculations describe all the measured observables within uncertainties only for correlation volumes that are different with respect to those describing proton yields and a similar measurement of net-proton number fluctuations.

Enhanced Deuteron Coalescence Probability in Jets

The transverse-momentum (p_{T}) spectra and coalescence parameters B_{2} of (anti)deuterons are measured in p-p collisions at sqrt[s]=13  TeV for the first time in and out of jets. In this measurement, the direction of the leading particle with the highest p_{T} in the event (p_{T}^{lead}>5  GeV/c) is used as an approximation for the jet axis. The event is consequently divided into three azimuthal regions, and the jet signal is obtained as the difference between the toward region, that contains jet fragmentation products in addition to the underlying event (UE), and the transverse region, which is dominated by the UE. The coalescence parameter in the jet is found to be approximately a factor of 10 larger than that in the underlying event. This experimental observation is consistent with the coalescence picture and can be attributed to the smaller average phase-space distance between nucleons in the jet cone as compared with the underlying event. The results presented in this Letter are compared to predictions from a simple nucleon coalescence model, where the phase-space distributions of nucleons are generated using pythia8 with the Monash 2013 tuning, and to predictions from a deuteron production model based on ordinary nuclear reactions with parametrized energy-dependent cross sections tuned on data. The latter model is implemented in pythia8.3. Both models reproduce the observed large difference between in-jet and out-of-jet coalescence parameters, although the almost flat trend of the B_{2}^{Jet} is not reproduced by the models, which instead give a decreasing trend.

Significantly longer time to deterioration of quality of life due to CANKADO PRO-React eHealth support in HR+ HER2- metastatic breast cancer patients receiving palbociclib and endocrine therapy: Primary outcome analysis of the multicenter randomized AGO-B WSG PreCycle trial

BACKGROUND

The multicenter, randomized phase IV intergroup AGO-B WSG PreCycle trial (NCT03220178) evaluated the impact of CANKADO-based ePRO (electronic patient-reported outcomes) assessment on quality of life (QoL) in HR+ HER2- locally advanced or metastatic breast cancer (MBC) patients receiving palbociclib (P) and an aromatase inhibitor or P+fulvestrant. CANKADO PRO-React, an EU-registered medical device, is an interactive autonomous application reacting to patient self-reported observations.

PATIENTS AND METHODS

Between 2017 and 2021, 499 patients (median age 59 years) from 71 centers were randomized (2:1, stratified by therapy line) between an active version of CANKADO PRO-React (CANKADO-active arm) or a version with limited functionality (CANKADO-inform arm). 412 patients (271 CANKADO-active; 141 CANKADO-inform) were available for analysis of the primary endpoint, time to deterioration (TTD) of QoL (10-point drop on FACT-G), using an Aalen-Johansen estimator for cumulative incidence function of TTD DQoL with 95% pointwise confidence intervals (CI). Secondary endpoints included PFS, OS, and DQoL (QoL deterioration).

RESULTS

In all pts (ITT-ePRO), cumulative incidence of DQoL was significantly more favorable (lower) in the CANKADO-active arm (HR=0.698, 95%CI [0.506 - 0.963]). Among 1^stL patients (n=295), the corresponding HR was 0.716 (0.484-1.060; p=0.09), and in 2^ndL patients (n=117) it was 0.661 (0.374-1.168; p=0.2). Absolute patient numbers declined in later visits; FACT-G completion rates were 80% and higher until about visit 30; mean FACT-G scores showed steady decline from baseline and an offset in favor of CANKADO-active. No significant differences in clinical outcome were observed between arms: Median PFS (ITT population) was 21.4 (95%CI 19.4-23.7) (CANKADO-active) and 18.7 (15.1-23.5) months (CANKADO-inform); median OS was not reached (CANKADO-active) and 42.6 months (CANKADO-inform).

CONCLUSIONS

PreCycle is the first multicenter randomized eHealth trial demonstrating a significant benefit for MBC patients receiving oral tumor therapy when using an interactive autonomous patient empowerment application.