Giant paramagnetism induced valley polarization of electrons in charge-tunable monolayer MoSe2

For applications exploiting the valley pseudospin degree of freedom in transition metal dichalcogenide monolayers, efficient preparation of electrons or holes in a single valley is essential. Here, we show that a magnetic field of 7 Tesla leads to a near-complete valley polarization of electrons in MoSe2 monolayer with a density 1.6x10^{12} cm^{-2}; in the absence of exchange interactions favoring single-valley occupancy, a similar degree of valley polarization would have required a pseudospin g-factor exceeding 40. To investigate the magnetic response, we use polarization resolved photoluminescence as well as resonant reflection measurements. In the latter, we observe gate voltage dependent transfer of oscillator strength from the exciton to the attractive-Fermi-polaron: stark differences in the spectrum of the two light helicities provide a confirmation of valley polarization. Our findings suggest an interaction induced giant paramagnetic response of MoSe2, which paves the way for valleytronics applications

Intense Molar Circular Dichroism in Fully Conjugated All-Carbon Macrocyclic 1,3-Butadiyne Linked pseudo-meta [2.2]Paracyclophanes

The synthetic access to macrocyclic molecular topologies with interesting photophysical properties has greatly improved thanks to the successful implementation of organic and inorganic corner units. Based on recent reports, we realized that pseudo-meta [2.2]paracyclophanes (PCPs) might serve as optimal corner units for constructing 3D functional materials, owing to their efficient electronic communication, angled substituents and planar chirality. Herein, we report the synthesis, characterization and optical properties of four novel all-carbon enantiopure macrocycles bearing three to six pseudo-meta PCPs linked by 1,3-butadiyne units. The macrocycles were obtained by a single step from enantiopure, literature-known dialkyne pseudo-meta PCP and were unambiguously identified and characterized by state of the art spectroscopic methods and in part even by x-ray crystallography. By comparing the optical properties to relevant reference compounds, it is shown that the pseudo-meta PCP subunit effectively elongates the conjugated system throughout the macrocyclic backbone, such that already the smallest macrocycle consisting of only three subunits reaches a polymer-like conjugation length. Additionally, it is shown that the chiral pseudo-meta PCPs induce a remarkable chiroptical response in the respective macrocycles, reaching unprecedented high molar circular dichroism values for all-carbon macrocycles of up to 1307 L mol-1 cm-1

Intense Molar Circular Dichroism in Fully Conjugated All‐Carbon Macrocyclic 1,3‐Butadiyne Linked pseudo‐ meta [2.2]Paracyclophanes**

The synthetic access to macrocyclic molecular topologies with interesting photophysical properties has greatly improved thanks to the successful implementation of organic and inorganic corner units. Based on recent reports, we realized that pseudo-meta [2.2]paracyclophanes (PCPs) might serve as optimal corner units for constructing 3D functional materials, owing to their efficient electronic communication, angled substituents and planar chirality. Herein, we report the synthesis, characterization and optical properties of four novel all-carbon enantiopure macrocycles bearing three to six pseudo-meta PCPs linked by 1,3-butadiyne units. The macrocycles were obtained by a single step from enantiopure, literature-known dialkyne pseudo-meta PCP and were unambiguously identified and characterized by state of the art spectroscopic methods and in part even by x-ray crystallography. By comparing the optical properties to relevant reference compounds, it is shown that the pseudo-meta PCP subunit effectively elongates the conjugated system throughout the macrocyclic backbone, such that already the smallest macrocycle consisting of only three subunits reaches a polymer-like conjugation length. Additionally, it is shown that the chiral pseudo-meta PCPs induce a remarkable chiroptical response in the respective macrocycles, reaching unprecedented high molar circular dichroism values for all-carbon macrocycles of up to 1307 L mol$^{−1}$ cm$^{−1}$

Implementation of a hospital-integrated general practice : a successful way to reduce the burden of inappropriate emergency-department use

Principles: Emergency departments (Eds) are over-crowded by lower acuity patients, which might be more efficiently treated by general practitioners (Gps). This study evaluated the impact of triaging lower acuity patients to a new hospital-integrated general practice (HGP) on ED case-load and the reasons for choosing the ED/HGP. Methods and Results: Patients were consecutively assessed according to the emergency severity index (ESI) to triage lower acuity patients to the HGP. Consultation numbers at the emergency centre (Ed and HGP) increased by 43% between 2007 (n=16974) and 2011 (n=24331) (implementation of HGP in 2009). Although self-referrals increased significantly at the emergency centre from 54% to 63% (p<0.001), the proportion of self-referrals at the ED was significantly reduced to 48% (p=0.007). The HGP was able to reduce the burden of increasing total consultations by 36%; 4.6% were referred back to the ED after triaging to the HGP. Overall, 95% of HGP patients were self-referred, Swiss nationals (65%) and with a personal GP (82%) they attended regularly (69%). The most common reason for presenting at the emergency centre was not being able to reach the GP(60%). Diagnoses were injury- (29%) and infection- (23%) related problems affecting the musculoskeletal (27%) system and skin (21%). Conclusion: The HGP succeeded in reducing the burden of inappropriate ED use: the majority of low acuity self-referred patients were conclusively treated at the HGP. The HGP does not represent competition to the GP out-of-hours care service, since the main reason for presenting at the hospital was not lacking a relationship but the Gps’in-accessibility

Walk-ins seeking treatment at an emergency department or general practitioner out-of-hours service: a cross-sectional comparison

Background Emergency Departments (ED) in Switzerland are faced with increasing numbers of patients seeking non-urgent treatment. The high rate of walks-ins with conditions that may be treated in primary care has led to suggestions that those patients would best cared for in a community setting rather than in a hospital. Efficient reorganisation of emergency care tailored to patients needs requires information on the patient populations using the various emergency services currently available. The aim of this study is to evaluate the differences between the characteristics of walk-in patients seeking treatment at an ED and those of patients who use traditional out-of-hours GP (General Practitioner) services provided by a GP-Cooperative (GP-C). Methods In 2007 and 2009 data was collected covering all consecutive patient-doctor encounters at the ED of a hospital and all those occurring as a result of contacting a GP-C over two evaluation periods of one month each. Comparison was made between a GP-C and the ED of the Waid City Hospital in Zurich. Patient characteristics, time and source of referral, diagnostic interventions and mode of discharge were evaluated. Medical problems were classified according to the International Classification of Primary Care (ICPC-2). Patient characteristics were compared using non-parametric tests and multiple logistic regression analysis was applied to investigate independent determinants for contacting a GP-C or an ED. Results Overall a total of 2974 patient encounters were recorded. 1901 encounters were walk-ins and underwent further analysis (ED 1133, GP-C 768). Patients consulting the GP-C were significantly older (58.9 vs. 43.8 years), more often female (63.5 vs. 46.9%) and presented with non-injury related medical problems (93 vs. 55.6%) in comparison with patients at the ED. Independent determining factors for ED consultation were injury, male gender and younger age. Walk-in distribution in both settings was equal over a period of 24 hours and most common during daytime hours (65%). Outpatient care was predominant in both settings but significantly more so at the GP-C (79.9 vs. 85.7%). Conclusions We observed substantial differences between the two emergency settings in a non gate-keeping health care system. Knowledge of the distribution of diagnoses, their therapy, of diagnostic measures and of the factors which determine the patients' choice of the ED or the GP-C is essential for the efficient allocation of resources and the reduction of costs

Fermi polaron-polaritons in charge-tunable atomically thin semiconductors

The dynamics of a mobile quantum impurity in a degenerate Fermi system is a fundamental problem in many-body physics. The interest in this field has been renewed due to recent ground-breaking experiments with ultracold Fermi gases. Optical creation of an exciton or a polariton in a two-dimensional electron system embedded in a microcavity constitutes a new frontier for this field due to an interplay between cavity coupling favouring ultralow-mass polariton formation6 and exciton–electron interactions leading to polaron or trion formation. Here, we present cavity spectroscopy of gate-tunable monolayer MoSe2 exhibiting strongly bound trion and polaron resonances, as well as non-perturbative coupling to a single microcavity mode. As the electron density is increased, the oscillator strength determined from the polariton splitting is gradually transferred from the higher-energy repulsive exciton-polaron resonance to the lower-energy attractive exciton-polaron state. Simultaneous observation of polariton formation in both attractive and repulsive branches indicates a new regime of polaron physics where the polariton impurity mass can be much smaller than that of the electrons. Our findings shed new light on optical response of semiconductors in the presence of free carriers by identifying the Fermi polaron nature of excitonic resonances and constitute a first step in investigation of a new class of degenerate Bose–Fermi mixtures.Physic

Implementation of a hospital-integrated general practice - a successful way to reduce the burden of inappropriate emergency-department use

PRINCIPLES Emergency departments (EDs) are overcrowded by lower acuity patients, which might be more efficiently treated by general practitioners (GPs). This study evaluated the impact of triaging lower acuity patients to a new hospital-integrated general practice (HGP) on ED case-load and the reasons for choosing the ED/HGP. METHODS AND RESULTS Patients were consecutively assessed according to the emergency severity index (ESI) to triage lower acuity patients to the HGP. Consultation numbers at the emergency centre (ED and HGP) increased by 43% between 2007 (n = 16 974) and 2011 (n = 24 331) (implementation of HGP in 2009). Although self-referrals increased significantly at the emergency centre from 54% to 63% (p <0.001), the proportion of self-referrals at the ED was significantly reduced to 48% (p = 0.007). The HGP was able to reduce the burden of increasing total consultations by 36%; 4.6% were referred back to the ED after triaging to the HGP. Overall, 95% of HGP patients were self-referred, Swiss nationals (65%) and with a personal GP (82%) they attended regularly (69%). The most common reason for presenting at the emergency centre was not being able to reach the GP (60%). Diagnoses were injury- (29%) and infection- (23%) related problems affecting the musculoskeletal (27%) system and skin (21%). CONCLUSION The HGP succeeded in reducing the burden of inappropriate ED use: the majority of low acuity self-referred patients were conclusively treated at the HGP. The HGP does not represent competition to the GP out-of-hours care service, since the main reason for presenting at the hospital was not lacking a relationship but the GPs' inaccessibility

Beyond the Rosenfeld Equation: Computation of Vibrational Circular Dichroism Spectra for Anisotropic Solutions

ISSN:1549-9618ISSN:1549-962

Longitudinal study on the colonisation and transmission of methicillin-resistant Staphylococcus aureus in pig farms.

Knowledge about the dynamics of methicillin-resistant Staphylococcus aureus (MRSA) in pigs lacks detail at the level of individual animal. The aim of our study was therefore to determine the colonisation status of MRSA in individual pigs from birth to slaughter in order to gain a better understanding of substantial factors involved in transmission. Two farrow-to-finish and two grow-to-finish herds were included in the study. A total of 1728 nasal swabs from 390 pigs and 592 environmental wipes were collected at 11 different time points. Intermittent colonisation throughout the entire production cycle was conspicuous in the tracking of MRSA in individual pigs. Almost all pigs from a MRSA-positive herd changed MRSA status several times, which implies that pigs are transiently rather than permanently colonised. We highly recommend the definition of MRSA status at herd level rather that at the level of the individual pig when considering prevention measures against MRSA. Therefore, to avoid the further spread of MRSA in countries with moderate prevalence, such as in Switzerland, defining farms as MRSA positive or MRSA negative and allowing the trade of pigs only within herds of the same status seems feasible. This will also be important for combating the further dissemination of livestock-associated (LA)-MRSA into healthcare facilities and the community via humans who have close contact with animals

Implementing a primary care center at an emergency departement and its impact on staff satisfaction

New service models for emergency health care are needed due to capacity overload of emergency departments (ED), decreasing attractiveness for health care professionals and dissatisfaction of general practitioners (GP) with their traditional out-of-hours emergency