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This paper proposes a new classification method for spatial data by adjusting prior class probabilities according to local spatial patterns. First, the proposed method uses a classical statistical classifier to model training data. Second, the prior class probabilities are estimated according to the local spatial pattern and the classifier for each unseen object is adapted using the estimated prior probability. Finally, each unseen object is classified using its adapted classifier. Because the new method can be coupled with both generative and discriminant statistical classifiers, it performs generally more accurately than other methods for a variety of different spatial datasets. Experimental results show that this method has a lower prediction error than statistical classifiers that take no spatial information into account. Moreover, in the experiments, the new method also outperforms spatial auto-logistic regression and Markov random field-based methods when an appropriate estimate of local prior class distribution is used.

We review recent progress and motivate the need for further developments in nuclear optical potentials that are widely used in the theoretical analysis of nucleon elastic scattering and reaction cross sections. In regions of the nuclear chart away from stability, which represent a frontier in nuclear science over the coming decade and which will be probed at new rare-isotope beam facilities worldwide, there is a targeted need to quantify and reduce theoretical reaction model uncertainties, especially with respect to nuclear optical potentials. We first describe the primary physics motivations for an improved description of nuclear reactions involving short-lived isotopes, focusing on its benefits for fundamental science discoveries and applications to medicine, energy, and security. We then outline the various methods in use today to build optical potentials starting from phenomenological, microscopic, and ab initio methods, highlighting in particular the strengths and weaknesses of each approach. We then discuss publicly-available tools and resources facilitating the propagation of recent progresses in the field to practitioners. Finally, we provide a set of open challenges and recommendations for the field to advance the fundamental science goals of nuclear reaction studies in the rare-isotope beam era., Comment: This paper is the outcome of the Facility for Rare Isotope Beams Theory Alliance (FRIB - TA) topical program "Optical Potentials in Nuclear Physics" held in March 2022 at FRIB. Its content is non-exhaustive, was chosen by the participants and reflects their efforts related to optical potentials

We present the first systematic nonlocal dispersive optical model analysis using both bound-state and scattering data of $^{16,18}$O, $^{40,48}$Ca, $^{58,64}$Ni, $^{112,124}$Sn, and $^{208}$Pb. In all systems, roughly half the total nuclear binding energy is associated with the most-bound 10% of the total nucleon density. The extracted neutron skins reveal the interplay of asymmetry, Coulomb, and shell effects on the skin thickness. Our results indicate that simultaneous optical model fits of inelastic scattering and structural data on isotopic pairs are effective for constraining asymmetry-dependent nuclear structural quantities otherwise difficult to observe experimentally., 6 pages, 3 figures

The energy density is calculated in coordinate space for $^{12}$C, $^{40}$Ca, $^{48}$Ca, and $^{208}$Pb using a dispersive optical model constrained by all relevant data including the corresponding energy of the ground state. The energy density of $^{8}$Be is also calculated using the Green's function Monte-Carlo method employing the Argonne/Urbana two and three-body interactions. The nuclear interior minimally contributes to the total binding energy due to the 4$\pi r^2$ phase space factor. Thus, the volume contribution to the energy in the interior is not well constrained. The dispersive-optical-model energy densities are in good agreement with \textit{ab initio} self-consistent Green's function calculations of infinite nuclear matter restricted to treat only short-range and tensor correlations. These results call into question the degree to which the equation of state for nuclear matter is constrained by the empirical mass formula. In particular, the results in this paper indicate that saturated nuclear matter does not require the canonical value of 16 MeV binding per particle but only about 13-14 MeV when the interior of $^{208}$Pb is considered., Comment: 15 pages, 13 figures

The neutron total cross sections $\sigma_{tot}$ of $^{16,18}$O, $^{58,64}$Ni, $^{103}$Rh, and $^{112,124}$Sn have been measured at the Los Alamos Neutron Science Center (LANSCE) from low to intermediate energies (3 $\leq E_{lab} \leq$ 450 MeV) by leveraging waveform-digitizer technology. The $\sigma_{tot}$ relative differences between isotopes are presented, revealing additional information about the isovector components needed for an accurate optical-model description away from stability. Digitizer-enabled $\sigma_{tot}$-measurement techniques are discussed and a series of uncertainty-quantified dispersive optical model (DOM) analyses using these new data is presented, validating the use of the DOM for modeling light systems ($^{16,18}$O) and systems with open neutron shells ($^{58,64}$Ni and $^{112,124}$Sn). The valence-nucleon spectroscopic factors extracted for each isotope reaffirm the usefulness of high-energy proton reaction cross sections for characterizing depletion from the mean-field expectation., Comment: 28 pages, 20 figures

A review of recent applications of the nonlocal dispersive optical model (DOM) is presented that allows a simultaneous description of nuclear structure and nuclear reactions. An assessment of the quality of the resulting potentials for $^{40}$Ca and $^{48}$Ca is discussed for the description of the $(e,e'p)$ reaction to valence hole states and the possibility of interpreting the data in terms of absolute spectroscopic factors. The relevance of these results in the context of conflicting interpretations between transfer and knockout reactions is pointed out as well as the importance of proton reaction cross sections for isotopes with neutron excess. Application of the nonlocal DOM to $^{48}$Ca incorporates the effect of the 8 additional neutrons and allows for an excellent description of elastic scattering data of both protons and neutrons. The corresponding neutron distribution constrained by all available data generates a prediction for the neutron skin that is larger than most mean-field and available \textit{ab initio} results. Results are presented for the most recent nonlocal DOM analysis of $^{208}$Pb., Comment: 7 pages, 3 figures, INPC2019 invited talk. arXiv admin note: substantial text overlap with arXiv:1812.07622

The nonlocal implementation of the dispersive optical model (DOM) provides all the ingredients for distorted-wave impulse-approximation (DWIA) calculations of the (e,e′p) reaction. It provides both the overlap function, including its normalization, and the outgoing proton distorted wave. This framework is applied to describe the knockout of a proton from the 0d32 and 1s12 orbitals in Ca40 with fixed normalizations of 0.71 and 0.60, respectively. Data were obtained in parallel kinematics for three outgoing proton energies: 70, 100, and 135 MeV. Agreement with the data is as good as, or better than, previous descriptions employing local optical potentials and overlap functions from Woods-Saxon potentials - both with standard nonlocality corrections - whose normalization (spectroscopic factor) and radius were fitted to the data. The present analysis suggests that slightly larger spectroscopic factors are obtained when nonlocal optical potentials are employed than those generated with local potentials. The results further suggest that the chosen kinematical window around 100 MeV proton energy provides the best and cleanest method to employ the DWIA for the analysis of this reaction. The conclusion that substantial ground-state correlations cannot be ignored when describing a closed-shell atomic nucleus is therefore confirmed in detail. To reach these conclusions, it is essential to have a complete description of the nucleon single-particle propagator that accounts for all elastic nucleon-scattering observables in a wide energy domain up to 200 MeV. The current nonlocal implementation of the DOM fulfills this requirement.

A nonlocal dispersive optical-model analysis has been carried out for neutrons and protons in $^{48}\mathrm{Ca}$. Elastic-scattering angular distributions, total and reaction cross sections, single-particle energies, the neutron and proton numbers, and the charge distribution have been fitted to extract the neutron and proton self-energies both above and below the Fermi energy. From the single-particle propagator resulting from these self-energies, we have determined the charge and neutron matter distributions in $^{48}\mathrm{Ca}$. A best fit neutron skin of $0.249\ifmmode\pm\else\textpm\fi{}0.023\text{ }\text{ }\mathrm{fm}$ is deduced, but values up to 0.33 fm are still consistent. The energy dependence of the total neutron cross sections is shown to have a strong sensitivity to the skin thickness.

We present an account of the current status of the theoretical treatment of inclusive $(d,p)$ reactions in the breakup-fusion formalism, pointing to some applications and making the connection with current experimental capabilities. Three independent implementations of the reaction formalism have been recently developed, making use of different numerical strategies. The codes also originally relied on two different but equivalent representations, namely the prior (Udagawa-Tamura, UT) and the post (Ichimura-Austern-Vincent, IAV) representations. The different implementations have been benchmarked, and then applied to the Ca isotopic chain. The neutron-Ca propagator is described in the Dispersive Optical Model (DOM) framework, and the interplay between elastic breakup (EB) and non-elastic breakup (NEB) is studied for three Ca isotopes at two different bombarding energies. The accuracy of the description of different reaction observables is assessed by comparing with experimental data of $(d,p)$ on $^{40,48}$Ca. We discuss the predictions of the model for the extreme case of an isotope ($^{60}$Ca) currently unavailable experimentally, though possibly available in future facilities (nominally within production reach at FRIB). We explore the use of $(d,p)$ reactions as surrogates for $(n,\gamma)$ processes, by using the formalism to describe the compound nucleus formation in a $(d,p\gamma)$ reaction as a function of excitation energy, spin, and parity. The subsequent decay is then computed within a Hauser-Feshbach formalism. Comparisons between the $(d,p\gamma)$ and $(n,\gamma)$ induced gamma decay spectra are discussed to inform efforts to infer neutron captures from $(d,p\gamma)$ reactions. Finally, we identify areas of opportunity for future developments, and discuss a possible path toward a predictive reaction theory.

A nonlocal dispersive optical-model analysis has been carried out for neutrons and protons in ^{48}Ca. Elastic-scattering angular distributions, total and reaction cross sections, single-particle energies, the neutron and proton numbers, and the charge distribution have been fitted to extract the neutron and proton self-energies both above and below the Fermi energy. From the single-particle propagator resulting from these self-energies, we have determined the charge and neutron matter distributions in ^{48}Ca. A best fit neutron skin of 0.249±0.023 fm is deduced, but values up to 0.33 fm are still consistent. The energy dependence of the total neutron cross sections is shown to have a strong sensitivity to the skin thickness.

The nucleon self-energies of $^{40}$Ca and $^{48}$Ca are determined using a nonlocal dispersive optical model (DOM). By enforcing the dispersion relation connecting the real and imaginary part of the self-energy, scattering and structure data are used to constrain these self-energies. The ability to calculate both bound and scattering states simultaneously puts these self-energies in a unique position to consistently describe exclusive knockout reactions such as $(e,e'p)$. The present analysis reveals the importance of high-energy proton reaction cross-section data in constraining spectroscopic factors required for the description of the $(e,e'p)$ cross sections. In particular, it is imperative that high-energy proton reaction cross-section data are measured for $^{48}$Ca in the near future so that the quenching of the spectroscopic factors in the $^{48}$Ca$(e,e'p)^{47}$K reaction can be unambiguously constrained using the DOM. Measurements of proton reaction cross sections in inverse kinematics employing rare isotope beams with large neutron excess will provide corresponding constraints on proton spectroscopic factors for exotic nuclei. Moreover, DOM generated spectral functions indicate that the quenching of spectroscopic factors compared to $^{40}$Ca is not only due to long-range correlation, but also partly due to the increase in high-momentum protons in $^{48}$Ca on account of the strong neutron-proton interaction. Single-particle momentum distributions of protons and neutrons in $^{48}$Ca calculated from these spectral functions confirm that neutron excess causes a higher fraction of high-momentum protons than neutrons., Comment: 6 pages, 6 figures

Background Little is known about the prevalence and associations of clinically relevant fatigue (CRF) in recurrence-free prostate cancer survivors. Patients and methods Four hundred and sixteen recurrence-free prostate cancer survivors who were >1 year post-radiotherapy or radical prostatectomy were surveyed. The prevalence of CRF (defined as Brief Fatigue Inventory >3) was determined and compared with a noncancer control group. Other measures included the Hospital Anxiety and Depression Scale, International Prostate Symptom Score, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire. Relationships between these factors and CRF were explored in univariate and multivariate analyses. Results Analyzable data were obtained from 91% (377/416) of patients. The prevalence of CRF was 29% (108/377) versus 16% (10/63) in the controls (P = 0.031). CRF was more common in post-radiotherapy than in post-prostatectomy 33% (79/240) versus 22% (29/133), P = 0.024. However, when other factors (current depression, anxiety, urinary symptoms, medical comorbidities, pain and insomnia) were controlled for, previous treatment did not predict CRF. Current depression [Hospital Anxiety and Depression Scale ≥8 was by far the strongest association [odds ratio 9.9, 95% confidence interval 4.2–23.5)]. Conclusions Almost one-third of recurrence-free prostate cancer survivors report CRF. Depression, anxiety, urinary symptoms, pain and insomnia measured at outcome are more strongly associated than type of cancer treatment previously received.

Net ecosystem calcification rates (NEC) and net photosynthesis (NP) were determined from CO 2 seawater parameters on the barrier coral reef of Kaneohe Bay, Oahu, Hawaii. Autosamplers were deployed to collect samples on the barrier reef every 2 h for six 48-hour deployments, two each in June 2008, August 2009, and January/February 2010. NEC on the Kaneohe Bay barrier reef increased throughout the day and decreased at night. Net calcification continued at low rates at night except for six time periods when net dissolution was measured. The barrier reef was generally net photosynthetic (positive NP) during the day and net respiring (negative NP) at night. NP controlled the diel cycles of the partial pressure of CO 2 (pCO 2 ) and aragonite saturation state (Ω arag ), resulting in high daytime Ω arag levels when calcification rates were at their peak. However, the NEC and NP diel cycles can become decoupled for short periods of time (several hours) without affecting calcification rates. On a daily basis, net ecosystem production (NEP) of the barrier reef was found to be sometimes net photosynthetic and sometimes net respiring and ranged from − 378 to 80 mmol m − 2 d − 1 when calculated using simple box models. Daily NEC of the barrier reef was positive (net calcification) for all deployments and ranged from 174 to 331 mmol CaCO 3 m − 2 d − 1 . Daily NEC was strongly negatively correlated with average daily pCO 2 (R 2 = 0.76) which ranged from 431 to 622 μatm. Daily NEC of the Kaneohe Bay barrier reef is similar to or higher than daily NEC measured on other coral reefs even though Ω arag levels (mean Ω arag = 2.85) are some of the lowest measured in coral reef ecosystems. It appears that while calcification rate and Ω arag are correlated within a single coral reef ecosystem, this relationship does not necessarily hold between different coral reef systems. It can be expected that ocean acidification will not affect coral reefs uniformly and that some may be more sensitive to increasing pCO 2 levels than others.

Primary cultures of human osteoblast-like cells are frequently used to study osteoblast function. Due to inhomogeneous growth of primary osteoblasts in culture, it is of interest if the use of confluence stages for analysis would reduce the overall variability. Consequently, we have tested the influence of degree of confluence and passage number on the growth and differentiation of human primary osteoblast-like cells. Phenotypic features of primary human osteoblast-like cells were compared at four successive cell densities defined as stage of confluence I (50%), stage II (75%), stage III (100%) and stage IV (5 days post confluence). The stability of the system was also tested by comparing these observations obtained using cells from the 2nd and 4th passages. As a sign for further differentiation, the number of AP-positive cells increased with a decrease in proliferation. The secretion of procollagen-I decreased to 50% during culture while procollagen I mRNA doubled from proliferation to confluence. A constant activity of alkaline phosphatase, procollagen-I secretion and procollagen I gene expression over passages was seen together with a decrease in growth. The paper introduces a potential model of osteoblastic differentiation in vitro for human primary osteoblast-like cells. We were able to show an increasing differentiation with a decrease in proliferation and the stability of this differentiation behaviour over cell passages in this model, but we were not able to reduce the overall variability.