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Abstract Three-dimensional (3D) electronic band structure is fundamental for understanding a vast diversity of physical phenomena in solid-state systems, including topological phases, interlayer interactions in van der Waals materials, dimensionality-driven phase transitions, etc. Interpretation of ARPES data in terms of 3D electron dispersions is commonly based on the free-electron approximation for the photoemission final states. Our soft-X-ray ARPES data on Ag metal reveals, however, that even at high excitation energies the final states can be a way more complex, incorporating several Bloch waves with different out-of-plane momenta. Such multiband final states manifest themselves as a complex structure and added broadening of the spectral peaks from 3D electron states. We analyse the origins of this phenomenon, and trace it to other materials such as Si and GaN. Our findings are essential for accurate determination of the 3D band structure over a wide range of materials and excitation energies in the ARPES experiment.

Band bending at semiconductor surfaces and interfaces is the key to applications ranging from classical transistors to topological quantum computing. A semiconductor particularly important for optical as well as microwave devices is GaN. What makes the material useful is not only its large bandgap but also that it can be heavily doped to become metallic. Here, we apply soft-x-ray angle-resolved photoelectron spectroscopy (ARPES) to metallic Si-doped GaN to explore the electron density and momentum-resolved band dispersions of the valence and conduction electrons varying through the surface band-bending region. We find an upward band bending, where the measured band occupation reduces toward the surface, as probed with low photon energies 1.4keV, where the photoelectron mean free path exceeds the spatial extent of the band-bending region. Our quantitative analysis of the experimental data describes the potential variation in the band-bending region via self-consistent Poisson-Schrödinger equations. We put forward an insightful model to simulate the ARPES spectra from this region through summing up the contribution from all atomic layers, weighted by the photoelectron mean free path, under in-phase conditions achieved at particular values of the photoelectron out-of-plane momentum. The model adequately describes the peculiarities of the ARPES spectra caused by the surface band bending, including the photon-energy dependence of the apparent band occupation and Fermi-surface area, and allows accurate determination of the band-bending profile and values of the photoelectron mean free path. Finally, comparison of our data with supercell density functional theory calculations reveals the preferential location of Si atoms as substitutional for Ga, with the doped electrons entering the GaN conduction bands without formation of separate impurity states as would occur for Si interstitials. Our theoretical and experimental results resolve fundamental questions underpinning device performance of the GaN-based and other semiconductor materials in general and demonstrate a general methodology for quantitative studies of electron states in the band-bending region.

Semiconductor heterostructures hosting two-dimensional electron gases are widely used today in high-electron-mobility transistors. Here, the authors probe the electronic structure in GaN/AlGaN, heterostructures, discovering planar anisotropy of the electron Fermi surface, offering new insights into transport properties.

In compounds containing 4f and 5f elements, hidden-order phases exist which are undetectable by many methods, the origins of which are debated. Here, the authors use photoemission and neutron scattering methods to show how such a multipolar-ordered phase emerges due to Fermi surface instability in CeB6.

Electronic structure of a molecular beam epitaxy-grown system of (In,Mn)As quantum dots (QDs) buried in GaAs is explored with soft-x-ray angle-resolved photoelectron spectroscopy (ARPES) using photon energies around 1 keV. This technique, ideally suited for buried systems, extends the momentum-resolving capabilities of conventional ARPES with enhanced probing depth as well as elemental and chemical state specificity achieved with resonant photoexcitation. The experimental results resolve the dispersive energy bands of the GaAs substrate buried in ∼2 nm below the surface, and the impurity states (ISs) derived from the substitutional Mn atoms in the (In,Mn)As QDs and oxidized Mn atoms distributed near the surface. An energy shift of the Mn ISs in the QDs compared to (In,Mn)As DMS is attributed to the band offset and proximity effect at the interface with the surrounding GaAs. The absence of any ISs in the vicinity of the VBM relates the electron transport in (In,Mn)As QDs to the prototype (In,Mn)As diluted magnetic semiconductor. The SX-ARPES results are supported by measurements of the shallow core levels under variation of probing depth through photon energy. X-ray absorption measurements identify significant diffusion of interstitial Mn atoms out of the QDs towards the surface, and the role of magnetic circular dichroism is to block the ferromagnetic response of the (In,Mn)As QDs. Possible routes are drawn to tune the growth procedure aiming at practical applications of the (In,Mn)As based systems. [ABSTRACT FROM AUTHOR]

Objective: The Rubber Hand Illusion (RHI) has previously been used to depict the hierarchy between visual, tactile and perceptual stimuli. Studies on schizophrenia inpatients (SZs) have found mixed results in the ability to first learn the illusion, and have yet to explain the learning process involved. This study's aim was two-fold: to examine the learning process of the RHI in SZs and healthy controls over time, and to better understand the relationship between psychotic symptoms and the RHI., Method: Thirty schizophrenia inpatients and 30 healthy controls underwent five different trials of the RHI over a two-week period., Results: As has been found in previous studies, SZs felt the initial illusion faster than healthy controls did, but their learning process throughout the trials was inconsistent. Furthermore, for SZs, no correlations between psychotic symptoms and the learning of the illusion emerged., Conclusion: Healthy individuals show a delayed reaction to first feeling the illusion (due to latent inhibition), but easily learn the illusion over time. For SZs, both strength of the illusion and the ability to learn the illusion over time are inconsistent. The cognitive impairment in SZ impedes the learning process of the RHI, and SZs are unable to utilize the repetition of the process as healthy individuals can., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Inositol is a key precursor for synthesis of phosphatidylinositol in a major second messenger signalling system. It is biologically active in syndromes such as respiratory distress syndrome but has been thought to be excluded from CNS by the blood-brain barrier. Oral inositol treatment of 8 patients is shown to significantly increase CSF inositol by almost 70%, suggesting possible CNS therapeutic applications of this compound and possible CNS side-effects of systemic therapy.

A solitary cervical metastasis of a typical carcinoid tumor was found in the subcutaneous tissue of an asymptomatic 38-yr-old woman. Investigations failed to disclose the primary site until the 5th yr, when she presented with carcinoid syndrome. Multifocal ileal carcinoid tumors were resected and debulking of abdominal metastases performed. Interferon and somatostatin analogue treatment resulted in remission. Solitary cervical metastasis is an exceedingly rare initial manifestation of a mid-gut carcinoid tumor, and poses a therapeutic dilemma. There are no directions in the literature as to whether a "wait-and-see" approach or exploration surgery is the preferred management when one is confronted by a cervical metastasis of typical carcinoid tumor of unknown primary site.

The hypothesis was tested that cancer, by virtue of it being a thrombotic diathesis, may enhance ischemic heart disease. Because cancer therapy may precipitate thromboembolism, the authors focused on patients with occult neoplasia before therapy. Occult cancer was defined as a time period of 2 years before a cancer diagnosis was established. Data obtained from the files of patients with the diagnosis of malignant tumors and admitted to a general hospital during a 3-year period were reviewed for coronary risk factors, coronary events, and characteristics of cancer. Indices of coronary instability were studied: the incidence of first coronary events, the incidence of all coronary events, and the coronary events burden. These indices were calculated for 366 patients with cancer (from the Department of Medicine files of 166 consecutive patients with cancer of several primary sites and from the surgical ward files of 100 consecutive patients with colorectal cancer and 100 consecutive patients with cancer of the prostate or bladder) and for 100 patients with benign prostatic hypertrophy. The patients with benign prostatic hypertrophy served as controls. A steep and statistically significant increase in coronary instability indices was observed in all groups of patients with cancer in the 2-year period before cancer diagnosis in comparison with the coronary instability indices of control patients (P less than or equal to 0.05 to 0.0001). Patients with colorectal cancer presented the highest indices in the 2-year period before cancer diagnosis, with unstable ischemic heart disease being reported in 18% and first coronary events in 10%. The coronary events burden was 0.92. The lowest indices among patients with cancer were recorded in those with prostatic and bladder cancer. Unstable ischemic heart disease occurred in 6% and first coronary events in 4%. The coronary events burden was 0.36. The indices were several times lower for control patients than for patients with cancer. Unstable ischemic heart disease occurred in 3% of control patients, and first coronary events in 2%. The coronary events burden was 0.15. Other possible etiologic factors, particularly the known coronary risk factors and anemia, were not statistically related with an increased risk of coronary events in the 2-year period before cancer diagnosis. Based on these epidemiologic data, it appears that there may be an association between occult cancer and coronary events.

In order to provide a common basis for treatment decisions and the future evaluation of breast cancer therapy, the breast cancer protocol used in our clinic was formulated for the computer. A system for the simulation of clinical reasoning was used which allows the physician to express the medical logic as a series of inferences to be confirmed or rejected on the basis of Boolean combinations of medical criteria. The system enables the physician to rearrange these criteria into a questionnaire for complete and accurate recording of patient data. These data are then fed into the computer to produce a patient status report and treatment recommendations. The data from 26 patients in various stages of breast cancer have been processed by the computer and the computer's conclusions compared to the assessment made by a junior physician in our department. In three cases the staging was not identical, in 15 cases the treatment decisions were not identical and in all cases investigations were left out by the physician. The system has been of considerable value in standardising patient examination and treatment and in training inexperienced physicians.

A jaundiced patient due to inoperable bile duct carcinoma was treated by a combination of surgery, radiotherapy, and chemotherapy. At the operation an intra-abdominal, extra-choledochal bypass of the tumor was performed with a T-tube obstruction 10 months after diagnosis, and no evidence of malignancy was seen. The T-tube was replaced by an Argyle tube. One year later jaundice reappeared, due to displacement of the tube, and islets of metastatic tumor ce and additional cytotoxic treatment was given. Three months later, after the patient's demise due to an unrelated cause, no evidence of the disease was found. This case demonstrates the importance of palliative by-passing of the tumor in order to relieve obstruction, thus enabling further oncological treatment, which may be, as in the present case, highly effective.

Combination chemotherapy was administered to 62 patients with metastatic breast cancer in the years 1977-9. The combination consisted of cyclophosphamide, methotrexate and 5-fluorouracil. The average age was 52.5 years, and the range from 27-76. Complete or partial remission for a period of 11.5 months (median) was achieved in 56.5%. Among 23 cases of lung metastases 48% had partial or complete remissions, among 16 cases of lymph node metastases 81%, and among 32 cases of bone metastases, 37.5%. Of six cases of local recurrence, 33.3% had partial remissions. Among four cases of liver metastases, 50% had objective responses. Among five cases of miscellaneous metastases, all had complete or partial responses. The median survival of the complete responders was 17 months, while that of the nonresponders was only 11 months. Side effected were tolerable and no deaths were attributed to the treatment.

Six female rabbits (Oryctolagus cuniculus) were experimentally infected intravenously with approximately 1.5 X 10(7) live spores of Encephalitozoon cuniculi. Head tilt was observed as the single clinical sign in only one of the six animals. Antibody response was registered over 68 days postinfection using the indirect immunofluorescence test (IFT) for IgM and IgG, and the carbon immunoassay (CIA). IgG titers reached a level of 160-2560 after a latent phase of 13-28 days, followed by a 2-4 week relatively steep increase. The IgM seroconversion was faster than that of IgG and occurred at the beginning of the antibody response. Thus, simultaneous detection of both IgM and IgG allowed the infection to be identified as recent. Long, short, and episodic antibody responses could be distinguished: the IgG titer continued to increase on Day 68 in one animal (long response) and began to decrease between Days 45 and 63 in three other animals (short response). In two additional animals the seroconversion was very short, occurring between Days 13 and 41, and 28 and 52, respectively (episodic response). The CIA proved to be specific, reliable, and simple to perform; titers were slightly higher than in the IFT. Parasite pseudocysts were detected scattered throughout the brain on Day 68 in four of the six rabbits. The persistence of antigen in the brain did not correlate with antibody response, which in most cases was shorter.