The formal theories of breakup reactions are reviewed. The direct breakup mechanism that is formulated within the framework of the post-form distorted-wave Born approximation, is discussed in detail. ...In this theory, which requires the information about only the ground state wave function of the projectile, the fragment–target interactions are included to all orders while fragment–fragment interaction is treated only in the first order. We put special emphasis on the breakup reactions of the near neutron drip line nuclei on heavy nuclear targets, which are dominated by the pure Coulomb breakup mechanism. The applicability of this theory to describe such reactions involving both spherical as well as deformed projectiles, is demonstrated by comparing the calculations with breakup data for total, energy and angle integrated cross sections and momentum distributions of fragments emitted in such reactions. Roles played by the pure Coulomb, pure nuclear and the Coulomb–nuclear interference terms in describing the breakup observables are discussed. Postacceleration effects in the Coulomb breakup of neutron halo nuclei are elaborated. The function of the pure Coulomb breakup mechanism in the one-neutron removal reactions of the type A(a,bγ)X on heavy target nuclei is underlined. The relationship between the parallel momentum distribution of the fragments and the break down of the magic numbers as the neutron drip line is approached, is highlighted.
Proper variance partitioning and estimation of genetic parameters at appropriate time interval is crucial for understanding the dynamics of trait variance and genetic correlations and for deciding ...the future breeding strategy of the population. This study was conducted on the same premise to estimate genetic parameters of major economic traits in a White Leghorn strain IWH using Bayesian approach and to identify the role of maternal effects in the regulation of trait variance. Three different models incorporating the direct additive effect (Model 1), direct additive and maternal genetic effect (Model 2) and direct additive, maternal genetic and maternal permanent environmental effects (Model 3) were tried to estimate the genetic parameters for body weight traits (birth weight, body weight at 16, 20, 40 and 52 weeks), Age at sexual maturity (ASM), egg production traits (egg production up to 24, 28, 40, 52, 64 and 72 weeks) and egg weight traits (egg weight at 28, 40 and 52 weeks). Model 2 and Model 3 with maternal effects were found to be the best having the highest accuracy for almost all the traits. The direct additive genetic heritability was moderate for ASM, moderate to high for body weight traits and egg weight traits and low to moderate for egg production traits. Though the maternal heritability (h.sup.2 .sub.mat) and permanent environmental effect (c.sup.2 .sub.mpe) was low (<0.1) for most of the traits, they formed an important component of trait variance. Traits like egg weight at 28 weeks (0.14±0.06) and egg production at 72 weeks (0.13±0.07) reported comparatively higher values for c.sup.2 .sub.mpe and h.sup.2 .sub.mat respectively. Additive genetic correlation was high and positive between body weight traits, between egg weight traits, between consecutive egg production traits and between body weight and egg weight traits. However, a negative genetic correlation existed between egg production and egg weight traits, egg production and body weight traits, ASM and early egg production traits. Overall, a moderate positive genetic correlation was estimated between ASM and body weight traits and ASM and egg weight traits. Based on our findings, we can deduce that maternal effects constitute an important source of variation for all the major economic traits in White Leghorn and should be necessarily considered in genetic evaluation programs.
Variance and covariance components of growth and production traits were analyzed employing REML animal model to assess the Dahlem Red (PD-3) chicken population for direct additive genetic, maternal ...effects and to estimate the estimated breeding value (EBV), genetic parameters, genetic trends and rate of inbreeding (ΔF) utilizing seven generation's data. The generation and hatch had significant (P≤0.01) effect on the body weight at 0 day (BW0), 2 (BW2), 4 (BW4) and 6 weeks (BW6) and shank length at six weeks of age (SL6). The average least squares means (LSM) for BW6 and SL6 were 273.93±0.62 g and 53.97±0.05 mm, respectively. All the production traits were significantly (P≤0.01) influenced by generation and hatch. The average LSM for age at sexual maturity (ASM), egg production up to 40 weeks (EP40) and egg mass up to 40 weeks (EM40) were 168.82±0.25 d, 72.60±0.41 eggs and 4.21±0.07 kg, respectively. Model 5 with additive direct, maternal genetic, maternal permanent environmental and residual variance components was the best for BW0, BW2 and BW4 based on the AIC values obtained in WOMBAT. Model 4 was the best model for BW6, SL6, ASM, EP40 and EM40 with additive direct, maternal permanent environmental and residual variance components. Maternal effects were higher during early age, decreased with age, and remained present until 20 weeks of age. The heritability (h2) estimates were low to moderate in magnitude for all the growth traits and ranged from 0.02±0.03 to 0.19±0.03. The maternal heritability was high at hatch (0.35±0.06), decreased gradually until 4th week (0.02±0.01) and ceased afterwards. The heritabilities of EP40 (0.11±0.03) and EM40 (0.12±0.04) were low. The direct additive genetic correlations (ra) between BW2, BW4, BW6 and SL6 were high and positive (P≤ 0.05). The additive genetic and maternal permanent environmental correlation between EP40 and EM40 were high and positive (P≤ 0.05). The EBV of EM40 was significant (P≤ 0.05) with 0.48 kg/generation in PD-3 chicken at the end of the seventh generation. The EBV of EP40 showed an increasing trend with a genetic gain of 1.87 eggs per generation. The average inbreeding coefficient of the population was 0.019 and average ΔF was 0.007 over the last seven generations of selection. The EBV trends for primary and associated traits showed linear trends in the desired direction and negligible inbreeding.
.
The one-neutron halos lying in the island of inversion around
N
=
20
has provided the podium to study the variation of total low-lying dipole strength with the neutron separation energy. We study ...three probable
p
-wave one-neutron halo candidates
31
Ne and
34
Na and
37
Mg lying in the island of inversion. A simple analytic model has been used for the calculation of the total low-lying dipole strength for the medium mass
p
-wave one-neutron halos. A correction factor to this analytical model has been estimated with a realistic Woods-Saxon potential. A comparison of these analytic calculations has been made with those performed by a finite-range distorted-wave Born approximation theory of the Coulomb dissociation. We also make an estimate of the one-neutron separation energies of
31
Ne,
34
Na and
37
Mg.
Earthquakes in the Himalayas pose a significant hazard to the densely populated Indo-Gangetic Plains (IGP). Due to liquefaction of soils, ground settlements and structural tilting are prevalent ...during earthquakes. This study aims to identify liquefaction potential zones in the North-Bihar region of the East Ganga Plains by performing morphotectonic analysis over six drainage basins and liquefaction susceptibility mapping using Analytical Hierarchy Process (AHP) while taking site-specific parameters into account. The Index of Relative Active Tectonic (IRAT) value for Gandak and Mahananda was determined to be 1, indicating that the basins are extremely active, whereas Burhi Gandak, Bagmati, and Kosi were moderately active with a 2 IRAT value. The Kamla basin is the least active with an IRAT value of 4. The Liquefaction Susceptibility Map (LSM) was divided into three categories: liquefaction not likely (24%), liquefaction possible (45%), and liquefaction likely (31%); the estimated RMSE values were 0.0084, 0.00048, and 0.00031, respectively. The integrated analysis, which employs both techniques, demonstrates how the individual basins will be affected by liquefaction during an earthquake. The proposed methodology would be beneficial to decision-makers when designing strategies for urban planning projects, as well as structural engineers when selecting sites for field-based surveys.
In March 2018, a large fissure closely parallel to the eastern rift belt of the East African Rift (EAR) system in Kenya emerged across the highway near Mai Mahiu town. It raises the possibility of ...rift tectonics aided by subsurface erosion. A thorough investigation was made based on remote sensing-based lineament analysis, land surface deformation by spaceborne geodetic techniques, and rainfall pattern vs denudational processes in the affected area in relation to local geology to adjudge the cause of the aseismic fissure. By conventional and advanced differential interferometric SAR (DInSAR and ADInSAR) and GNSS data analyses aided by the knowledge of generalised rift direction obtained from remote-sensing based lineament analysis, we inferred miniature dike intrusion and reactivation of pre-existing fault in a transiently elevated extensional regime. Episodic magmatic inflation in the Mt Longonot volcano and sudden increase in hydrological loading due to prolonged torrential rainfall led to the elevated extension and fracturing of the magma chamber, which prompted to miniature dyke intrusion along the pre-existing NNW-SSE fault, reactivation of faults and fractures and subtle rifting on SW dipping normal fault. Further, internal erosion in porous and permeable sandy soil and volcaniclastic deposits led to cavity formation along the reactivated weak plane, which finally led to the emergence of the ground fissure. In this paper, we presented our observations on volcano movements (due to magmatic inflation), reactivation of the pre-existing fault(s)/fracture(s) and, finally, their linkage with the formation of the surface fissure in an area with favourable geomorphology, rock and soil properties for internal erosion during heavy torrential rainfall.
In order to examine the progressive chemical evolution of halogens (F, Cl, Br, I) in altered ocean crust (AOC) during prograde subduction, this study compares bulk and in situ halogen concentrations ...in mafic samples from three petrogenetically related exhumed terrains in the Western Alps (the Chenaillet ophiolite, the Queyras ophiolites of the Schistes Lustrés, and the Monviso ophiolite). Samples from the Chenaillet ophiolite represent oceanic crust unaffected by metamorphic halogen loss and define a protolith halogen content (122 μg/g F, 29 μg/g Cl, 82 ng/g Br, and 98 ng/g I). Samples from the Queyras ophiolites experienced blueschist facies conditions, undergoing recrystallization and halogen loss (74 μg/g F, 19 μg/g Cl, 70 ng/g Br, and 63 ng/g I). Eclogite facies samples from the Monviso meta‐ophiolite exhibit markedly reduced Cl (8 μg/g Cl) and Br (42 ng/g Br) contents relative to samples from Chenaillet and Queyras. Using electron probe microanalysis (EPMA), F and Cl host minerals (e.g., amphibole, chlorite, epidote) are identified and characterized in selected samples, showing a broad distribution of F and Cl, lending support to the view that halogen devolatilization in the subducting slab occurs continuously and is not dependent on the breakdown of a particular phase. In situ Cl concentrations decrease significantly between sub‐greenschist and blueschist assemblages. Fluorine is retained within subducting AOC and is decoupled from the heavy halogens (Cl, Br, I), which undergo continuous devolatilization during prograde metamorphism.
Plain Language Summary
Halogens are volatile elements found predominantly in the Earth's oceans and sediments. During hydrothermal processes, they bond with other elements to form volatile‐bearing minerals. Tectonic processes can bring halogen‐enriched rocks into subduction zones, regions where one tectonic plate submerges beneath another. Subduction governs the transport of material from Earth's surface to its interior, influencing the chemical evolution of the crust, atmosphere, hydrosphere, and mantle. As the subducting plate carries rocks to greater depths beneath the surface, volatile‐bearing minerals destabilize, releasing volatile components as fluids. Halogens alter the properties of subduction‐derived fluids and impact the behavior of other biologically, climatically, and economically important elements (e.g., H2O, CO2, Au). Due to the influential role of halogens in subduction zone environments, the timing and extent of halogen loss must be constrained. This study investigates metamorphic rock samples from the Western Alps which underwent halogen‐enrichment followed by subduction and devolatilization. Results show that halogens behave differently from each other. Fluorine is not removed; it is retained until deep in the subduction zone and is returned to the Earth's mantle. The efficient removal of the other halogens occurs early in subduction (<60 km depth) and is not linked to the destabilization of a specific mineral.
Key Points
Exhumed ophiolites in the Western Alps record prograde subduction zone metamorphism and halogen devolatilization of altered ocean crust
Results show halogen decoupling. Fluorine is retained, whereas heavy halogens are mobilized from mafic rocks in the subducting slab
Devolatilization of altered ocean crust occurs early in subduction; a significant portion of Cl, Br, and I is lost prior to eclogite facies
In the conventionally fractionated phase III FLAME prostate trial, focal boosts improved local control and biochemical disease-free survival (bDFS). We explored the toxicity and effectiveness of a ...moderately hypofractionated schedule with focal boosts.
BIOPROP20 is a phase II single-arm non-randomised trial for intermediate- to very high-risk localised prostate cancer patients with bulky tumour volumes. Multi-parametric magnetic resonance imaging (MRI) and 18F-choline positron emission tomography-computed tomography (PET-CT) scans were used for staging and boost volume definition. Patients were treated with 60Gy in 20 fractions with a boost dose up to 68Gy. Five patients with positive lymph nodes on the PET-CT scan received radiotherapy to pelvic lymph nodes (45Gy to elective nodes, boosted up to 50Gy to involved nodes). Primary outcomes were acute (≤18 weeks) and late urinary and gastrointestinal toxicity, prospectively recorded up to 5 years with Common Terminology Criteria for Adverse Events v4 (CTCAE). Secondary outcomes were biochemical or clinical progression, metastasis-free survival (MFS), and overall survival (OS).
61 patients completed radiotherapy with hormone therapy (range: 6–36 months). Cumulative acute and late gastrointestinal toxicity was low at 6.6% and 5.0%, respectively. Cumulative acute and late urinary toxicity was 49.2% and 30.1%, respectively; the prevalence reduced to 5.9% at 5 years. At 5 years: 6 patients had biochemical progression (bDFS: 88.5%; 95% CI: 80.2–97.6%), the MFS was 82.4% (95% CI: 73.0–92.9%), 5 patients died (OS: 91.2%; 95% CI: 84.1–98.9%), one with prostate cancer. The prostate, boost, nodal planning volumes, and the organs at risk (rectum, bowel, urethra, and bladder) met the optimal protocol dose constraints. There was a trend to increased urinary toxicity with increasing urethral (RR: 1.95, 95% CI: 0.73–5.22, p = 0.18), but not bladder dose.
Focal boosts with a 20 fraction hypofractionated prostate radiotherapy schedule are associated with an acceptable risk of gastrointestinal and urinary toxicity and achieve good cancer control.
NCT02125175.
•Focal boosting is a safe prostate radiotherapy technique with a low toxicity profile.•It can be used with moderately fractionated radiotherapy schedules (20 fractions).•High-risk localised prostate cancer patients achieve excellent long-term outcomes.•Patients with PET-avid pelvic lymph nodes were treated with prostate focal boost, pelvic node and nodal boost radiotherapy.
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