Direct assessment of the proton affinity of individual surface hydroxyls with non-contact atomic force microscopy

The state of protonation/deprotonation of surfaces has far-ranging implications in all areas of chemistry: from acid-base catalysis$^1$ and the electro- and photocatalytic splitting of water$^2$, to the behavior of minerals$^3$ and biochemistry$^4$. The acidity of a molecule or a surface site is described by its proton affinity (PA) and pK$_\mathrm{a}$ value (the negative logarithm of the equilibrium constant of the proton transfer reaction in solution). For solids, in contrast to molecules, the acidity of individual sites is difficult to assess. For mineral surfaces such as oxides they are estimated by semi-empirical concepts such as bond-order valence sums$^5$, and also increasingly modeled with first-principles molecular dynamics simulations$^{6,7}$. Currently such predictions cannot be tested - the experimental measures used for comparison are typically average quantities integrated over the whole surface or, in some cases, individual crystal facets$^8$, such as the point of zero charge (pzc)$^9$. Here we assess individual hydroxyls on In$_2$O$_3$(111), a model oxide with four different types of surface oxygen atoms, and probe the strength of their hydrogen bond with the tip of a non-contact atomic force microscope (AFM). The force curves are in quantitative agreement with density-functional theory (DFT) calculations. By relating the results to known proton affinities and pK$_\mathrm{a}$ values of gas-phase molecules, we provide a direct measure of proton affinity distributions at the atomic scale

Outpatient multidisciplinary cancer rehabilitation in Switzerland: a status assessment

Aim This study aimed to assess the situation of outpatient multidisciplinary cancer rehabilitation in Switzerland as of March 2018. Subject and methods Seventeen programmes providing outpatient cancer rehabilitation were identified; 12 in the German-speaking, 4 in the French-speaking and 1 in the Italian-speaking part of Switzerland. Structure, organisation, type of programme and details on therapies offered were assessed. Difference by language regions and the status of the programme (running vs in development) were examined in a descriptive analysis. Results Centres in the German- and Italian-speaking parts had mostly individual modular programmes with a longer duration (median: 12 weeks) and low intensity (median: 2.5–3 h per week). The French-speaking part had standard programmes with a shorter duration (median: 9 weeks) but higher intensity (median: 5.5 h per week) and a higher number of obligatory modules a patient must attend (median: 2 instead of 1). The language regions also showed differences in duration of therapies, communication, indications and screening instruments. Conclusion Outpatient cancer rehabilitation in Switzerland is characterized by a wide range of programmes. These differences between language regions, as well as between the individual programmes, highlight important variables that may influence the efficiency and the quality of the different programmes; understanding these variables could lead to improvements in cancer rehabilitation in Switzerland

Adsorption configurations of Co-phthalocyanine on In2O3(111)

Indium oxide offers optical transparency paired with electric conductivity, a combination required in many optoelectronic applications. The most-stable In2O3(111) surface has a large unit cell (1.43 nm lattice constant). It contains a mixture of both bulk-like and undercoordinated O and In atoms and provides an ideal playground to explore the interaction of surfaces with organic molecules of similar size as the unit cell. Non-contact atomic force microscopy (nc-AFM), scanning tunneling microscopy (STM), and density functional theory (DFT) were used to study the adsorption of Co-phthalocyanine (CoPc) on In2O3(111). Isolated CoPc molecules adsorb at two adsorption sites in a 7:3 ratio. The Co atom sits either on top of a surface oxygen ('F configuration') or indium atom ('S configuration'). This subtle change in adsorption site induces bending of the molecules, which is reflected in their electronic structure. According to DFT the lowest unoccupied molecular orbital of the undistorted gas-phase CoPc remains mostly unaffected in the F configuration but is filled by one electron in S configuration. At coverages up to one CoPc molecule per substrate unit cell, a mixture of domains with molecules in F and S configuration are found. Molecules at F sites first condense into a F-(2x2) structure and finally rearrange into a F-(1x1) symmetry with partially overlapping molecules, while S-sited molecules only assume a S-(1x1) superstructure

The prototypical organic-oxide interface: intra-molecular resolution of sexiphenyl on In2_2O3_3(111)

The performance of an organic-semiconductor device is critically determined by the geometric alignment, orientation, and ordering of the organic molecules. While an organic multilayer eventually adopts the crystal structure of the organic material, the alignment and configuration at the interface with the substrate/electrode material is essential for charge injection into the organic layer. This work focuses on the prototypical organic semiconductor para-sexiphenyl (6P) adsorbed on In$_2$O$_3$(111), the thermodynamically most stable surface of the material that the most common transparent conducting oxide, indium tin oxide (ITO) is based on. The onset of nucleation and formation of the first monolayer are followed with atomically-resolved scanning tunneling microscopy (STM) and non-contact atomic force microscopy (nc-AFM). Annealing to 200$^\circ$C provides sufficient thermal energy for the molecules to orient themselves along the high-symmetry directions of the surface, leading to a single adsorption site. The AFM data suggests a twisted adsorption geometry. With increasing coverage, the 6P molecules first form a loose network with poor long-range order. Eventually the molecules re-orient and form an ordered monolayer. This first monolayer has a densely packed, well-ordered (2$\times$1) structure with one 6P per In$_2$O$_3$(111) substrate unit cell, i.e., a molecular density of 5.64$\times$10$^{13}$ cm$^{-2}$

National study for multidisciplinary outpatient oncological rehabilitation: online survey to support revised quality and performance criteria

PURPOSE More and more people survive cancer, but the disease and its treatment often lead to impairment. Multidisciplinary ambulatory oncological rehabilitation (OR) programs have thus been developed. SW!SS REHA, the organization of major Swiss rehabilitation clinics, has defined ambulatory OR quality criteria for its members (about 50% of the Swiss rehabilitation capacity). However, SW!SS REHA criteria are not fully implemented and/or interpreted differently by different specialties or in different linguistic regions in Switzerland. The aim of our study was to carry out an online survey of existing outpatient programs to define quality criteria for an ideal OR program in Switzerland. METHODS A mixed methods approach was used for the survey-qualitative and quantitative. The qualitative part consisted of a guided discussion with OR experts and the quantitative part of an online survey. The quantitative part comprised the development and evaluation of an online questionnaire. It served to record the opinions of OR centers in Switzerland on the desired situation of outpatient rehabilitation. RESULTS Eighteen OR centers and 71 (49.7% response rate) OR actors participated in the online survey. The survey results indicate that some of the SW!SS REHA quality and performance criteria only partially match with the desired OR criteria for Switzerland. Key disparities occur particularly in the program design and structure and specifically around how many interventions are required to constitute an OR program, the extent of standardization versus individualization of the program, i.e., how many and which modules in a program should be obligatory, and finally the duration and intensity of the program. The online survey did not generate any statistical evidence that OR requirements vary significantly between different linguistic regions and among different specialties. CONCLUSIONS Cancer patients are heterogeneous with respect to cancer type, prognosis, and disability level, such that a standard program cannot be uniformly applied. Therefore, a flexible program is required with few mandatory modules and additional individual modules to achieve the threshold number of modules that would constitute a multidisciplinary OR program. Intensity and frequency of OR needs to consider the health state of the participants. The results indicate a need to modify some of the existing SW!SS REHA criteria to ensure that more patients can gain access and benefit form evidence-based OR interventions. Furthermore, the survey provides important findings so that the existing OR offer can be improved with the goal that OR centers will be able to be quality certified in the future

Water Structures Reveal Local Hydrophobicity on the In2O3(111) Surface

Clean oxide surfaces are generally hydrophilic. Water molecules anchor at undercoordinated surface metal atoms that act as Lewis-acid sites, and they are stabilized by H bonds to undercoordinated surface oxygens. The large unit cell of In2O3(111) provides surface atoms in various configurations, which leads to chemical heterogeneity and a local deviation from this general rule. Experiments (TPD, XPS, ncAFM) agree quantitatively with DFT calculations and show a series of distinct phases. The first three water molecules dissociate at one specific area of the unit cell and desorb above room temperature. The next three adsorb as molecules in the adjacent region. Three more water molecules rearrange this structure and an additional nine pile up above the OH groups. Despite offering undercoordinated In and O sites, the rest of the unit cell is unfavorable for adsorption and remains water-free. The first water layer thus shows ordering into nanoscopic 3D water clusters separated by hydrophobic pockets

Myxofibrosarcoma of the thyroid gland

AbstractIntroductionMyxofibrosarcoma of the thyroid is exceptional: a Medline search found a single case report. We report a new case which raised diagnostic and therapeutic problems.ObservationWe report the case of a 74-year-old woman who presented with swelling of the left thyroid lobe and ipsilateral cervical lymphadenopathy. Total thyroidectomy with cervical lymph-node dissection was performed. Histological analysis diagnosed myxofibrosarcoma. Evolution was marked by rapid local recurrence, and chemotherapy based on doxorubicin and ifosfamide was introduced.Discussion/conclusionHead and neck myxofibrosarcoma is rare. MRI is essential and should always precede treatment. Diagnosis is histological. There is elevated risk of local recurrence after resection, accompanied by worsening tumor grade, whence the need for accurate diagnosis, appropriate treatment and regular MRI follow-up