[Interprofessional weaning boards and weaning consults for long-term ventilated patients: A qualitative study of perceived potential for patient care]

BACKGROUND

The PRiVENT project aims to improve the care of invasively ventilated patients and to reduce the number of out-of-hospital long-term ventilated patients. PRiVENT offers intensive care units the opportunity to exchange information with experts from specialized weaning centers in interprofessional weaning boards and weaning consults and to exploit the full weaning potential of the patients. In the context of the accompanying process evaluation, the PRiVENT intervention components will be examined for sustainability, scalability and effectiveness, and the interprofessional collaboration between intensive care units and the responsible weaning centers will be investigated in order to identify potentials for the care of invasively managed patients.

METHODS

In a qualitative cross-sectional study, semistructured, problem-oriented interviews were conducted with care providers of participating ICUs. The data were digitally recorded, pseudonymized and verbatim transcribed. Data analysis was based on Brown and Clarke's Thematic Analysis and the Consolidated Framework for Implementation Research. MAXQDA 2020 software was used to organize the data.

RESULTS

Fourteen interviews were conducted with ICU care providers. The early transfer of patients to a weaning center and the integration of pulmonary expertise into routine care were identified as positively perceived potentials of the weaning boards and weaning consults. Especially in critically ill, multimorbid patients suffering from COVID-19, the expertise of the weaning centers was considered helpful. Due to heavy workloads, nurses were unable to participate in weaning boards and weaning consults.

CONCLUSION

Interprofessional collaboration between weaning centers and ICUs in weaning boards and weaning consults can improve the care of invasively ventilated patients. Strategies to promote the involvement of nurses should be discussed and developed.

[Between New Responsibility and Daily Routines - The Role of the VERAH in GP Care: A Qualitative Secondary Data Case Study of the Introduction of Software-Based Case Management]

BACKGROUND

The concept of Care Assistant in General Practice (VERAH) was developed in order to integrate non-medical staff more strongly into primary care and thus to meet the increasing demand for care and the simultaneous shortage of medical staff. VERAHs are increasingly responsible for software-supported case management and are thus confronted with new tasks. The aim of this study was therefore to explore the role of the VERAH in primary care practices.

METHODS

The present study is a qualitative secondary data analysis; the data collection took place within the projects VESPEERA and TelePraCMan. Twenty individual interviews and two focus group meetings were conducted with a total of 30 physicians, VERAHs and medical assistants from primary care. The data were analysed qualitatively according to Emerson. Contextual and socio-demographic data were collected with an accompanying questionnaire.

RESULTS

The VERAHs of all primary care practices from which interview partners participated performed tasks within software-supported case management. Concerning the role of the VERAH, three themes were identified in the interviews: a) concrete tasks of the VERAH in software-supported case management within the practice team, b) relevance of software-supported case management within the activities of the VERAHS and c) relationship between VERAHs and patients.

CONCLUSION

Taking over tasks in software-supported case management can contribute to strengthening and expanding the role of the VERAH. In the future, more attention should be paid to a clear description of the new role, and the conditions of the VERAHs' task fulfilment should be considered.

Climate change mitigation: Qualitative analysis of environmental impact-reducing strategies in German primary care

BACKGROUND

The German healthcare system is responsible for 5,2% of the national emissions of greenhouse gases. Therefore, mitigation actions to reduce the carbon footprint are crucial. However, there have been few approaches to achieve this in German primary care.

OBJECTIVES

This study aimed to identify environmental impact-reducing strategies of German primary care practices.

METHODS

During the summer of 2021, a qualitative study was conducted using interviews and focus groups with experts in primary care across Germany, such as physicians, medical assistants, health scientists and experts on the health system level. Verbatim transcribed data were analyzed using Thematic Analysis.

RESULTS

The sample comprised 26 individual interviews and two focus groups with a total of N = 40 participants. Findings provide a first overview of pursued mitigation strategies and contextual factors influencing their implementation. Strategies referred to the use of water and energy, recycling and waste management, supply chains and procurement, digitisation, mobility, patient care, behavioural changes and system level. Implementing sustainable actions in daily care was considered expensive and often unfeasible due to lack of staff, time and restrictive hygiene regulations. Participants called for more instruction on implementing mitigating actions, for example, through websites, podcasts, guidelines or quality indicators.

CONCLUSION

This study's findings can support the development of future environmental impact-reducing strategies in primary care. Potential options for guidance and support should be considered to facilitate sustainability.

Prevention of invasive ventilation (PRiVENT)-a prospective, mixed-methods interventional, multicentre study with a parallel comparison group: study protocol

BACKGROUND

Invasive mechanical ventilation (IMV) is a standard therapy for intensive care patients with respiratory failure. With increasing population age and multimorbidity, the number of patients who cannot be weaned from IMV increases, resulting in impaired quality of life and high costs. In addition, human resources are tied up in the care of these patients.

METHODS

The PRiVENT intervention is a prospective, mixed-methods interventional, multicentre study with a parallel comparison group selected from insurance claims data of the health insurer Allgemeine Ortskrankenkasse Baden-Württemberg (AOK-BW) conducted in Baden-Württemberg, Germany, over 24 months. Four weaning centres supervise 40 intensive care units (ICUs), that are responsible for patient recruitment. The primary outcome, successful weaning from IMV, will be evaluated using a mixed logistic regression model. Secondary outcomes will be evaluated using mixed regression models.

DISCUSSION

The overall objective of the PRiVENT project is the evaluation of strategies to prevent long-term IMV. Additional objectives aim to improve weaning expertise in and cooperation with the adjacent Intensive Care Units.

TRIAL REGISTRATION

This study is registered at ClinicalTrials.gov (NCT05260853).

Interprofessional weaning boards for invasively ventilated patients in intensive care units: Qualitative interview study with healthcare professionals in Germany

Numbers of mechanically ventilated patients are increasing worldwide. Weaning Boards could support weaning from the ventilator by facilitating interprofessional consultations between Weaning Centers and nonpneumological intensive care units. This study, which is linked to the project Prevention of invasive Ventilation, aimed to explore the design and implementation of future Weaning Boards. Semistructured interviews were conducted with physicians, nurses, respiratory therapists, and physiotherapists of intensive care units and Weaning Centers in Baden-Wuerttemberg, Germany. Participants were asked to share their views on (a) required characteristics of Weaning Boards and (b) the current care of weaning patients in their wards. Qualitative data analysis included inductive and deductive steps referring to the Template for Intervention Description and Replication checklist and the Consolidated Framework for Implementation Research. The 14 interviewed healthcare professionals addressed characteristics of future Weaning Boards including (a) preconditions, (b) procedure, (c) interprofessional participants, (d) type of performance, and (d) time frame. Identified determinants for successful implementation were related to (a) individual characteristics of healthcare professionals, (b) ward characteristics, and (c) healthcare system characteristics. Weaning Boards could be a useful tool to advance knowledge sharing between professionals, improve education about weaning protocols, and support patient-oriented care. The implementation of Weaning Boards can be influenced by individual characteristics of participating professionals, difficulties in the interaction between professional groups, the present workplace culture, and the current coronavirus disease 2019 (COVID-19) pandemic.

Building resilience in German primary care practices: a qualitative study

Background

In recent years, healthcare has faced many different crises around the world such as HIV-, Ebola- or H1N1-outbrakes, opioid addiction, natural disasters and terrorism attacks). In particular, the current pandemic of Covid-19 has challenged the resilience of health systems. In many healthcare systems, primary care practices play a crucial role in the management of crises as they are often the first point of contact and main health care provider for patients. Therefore, this study explored which situations are perceived as crises by primary care practice teams and potential strategies for crisis management.

Methods

A qualitative observational study was conducted. Data were collected in interviews and focus groups with experts from primary care practices and stakeholders focusing on primary care practices in Germany such as physicians, medical assistants, practice managers, quality managers, hygiene managers and institutions on health system level (politics, research and health insurance). All interviews and focus groups were audio-recorded and transcribed verbatim. A qualitative content analysis was performed using a rapid qualitative analysis approach first, followed by a thematic analysis.

Results

Two focus groups and 26 interviews including 40 participating experts were conducted. Many different situations were perceived as crises, varying from issues in the practice organization to problems on health system level and international disasters. Distinct aspects associated with the perception of a crisis situation by interviewees were the presence of emotional reactions, a need for organizational changes and a lack of necessary resources. A broad spectrum of possible strategies was discussed that could help to cope with or even prevent the emergence of an actual crisis. In particular, strengthening communication within practice teams and resilience among employees was perceived to be fundamental for improving responses to crises or preventing them.

Conclusions

The study provides perspectives of primary health care workers on crises in health, that could inform health policy regarding prevention and management of future crises in primary care facilities.

Effects and Processes of an mHealth Intervention for the Management of Chronic Diseases: Prospective Observational Study

Background

Mobile health (mHealth) interventions for self-management are a promising way to meet the needs of patients with chronic diseases in primary care practices. Therefore, an mHealth intervention, TelePraCMan, was developed and evaluated for patients with type 2 diabetes mellitus, chronic obstructive pulmonary disease, high blood pressure, or heart failure in a German primary care setting. TelePraCMan entails a symptom diary, an appointment manager, a manager to document goals, and a warning system. The app should foster the self-management of participating patients.

Objective

We aimed to examine the effects of TelePraCMan on patient activation and quality of life and explored the underlying contextual factors, impacts, and degree of implementation.

Methods

In a prospective observational study design, we collected data by using interviews and written questionnaires from participating patients (intervention and control groups) and primary care workers (physicians and practice assistants). The primary outcomes of interest were patient-reported quality of life (12-Item Short Form Survey) and patient activation (patient activation measure). The quantitative analysis focused on differences between patients in the intervention and control groups, as well as before (T0) and after (T1) the intervention. Interviews were analyzed by using qualitative content analysis via MAXQDA (VERBI GmbH).

Results

At baseline, 25 patients and 24 primary care workers completed the questionnaire, and 18 patients and 21 primary care workers completed the follow-up survey. The patients were predominantly male and, on average, aged 64 (SD 11) years (T0). The primary care workers were mostly female (62%) and, on average, aged 47 (SD 10) years (T0). No differences were observed in the outcomes before and after the intervention or between the intervention and control groups. In the additional interviews, 4 patients and 11 primary care workers were included. The interviewees perceived that the intervention was useful for some patients. However, contextual factors and problems with implementation activities negatively affected the use of the app with patients. The main reasons for the low participation were the COVID-19 pandemic and the target group, which seemed to have less interest in mHealth; the interviewees attributed this to the older age of patients. However, the respondents felt that the app would be better accepted in 5 or 10 years.

Conclusions

Although the TelePraCMan app was rated as very good and important by the participants, few patients used it. The digital intervention was hardly implemented and had limited impact in the current setting of German primary care.

Trial Registration

German Clinical Trials Register DRKS00017320; https://tinyurl.com/4uwrzu85

Risk Factors for Prolonged Mechanical Ventilation and Weaning Failure: A Systematic Review

INTRODUCTION

Prolonged mechanical ventilation (PMV) and weaning failure are factors associated with prolonged hospital length of stay and increased morbidity and mortality. In addition to the burden these places on patients and their families, it also imposes high costs on the public health system. The aim of this systematic review was to identify risk factors for PMV and weaning failure.

METHODS

The study was conducted according to PRISMA guidelines. After a comprehensive search of the COCHRANE Library, CINHAL, Web of Science, MEDLINE, and the LILACS Database a PubMed request was made on June 8, 2020. Studies that examined risk factors for PMV, defined as mechanical ventilation ≥96 h, weaning failure, and prolonged weaning in German and English were considered eligible; reviews, meta-analyses, and studies in very specific patient populations whose results are not necessarily applicable to the majority of ICU patients as well as pediatric studies were excluded from the analysis. This systematic review was registered in the PROSPERO register under the number CRD42021271038.

RESULTS

Of 532 articles identified, 23 studies with a total of 23,418 patients met the inclusion criteria. Fourteen studies investigated risk factors of PMV including prolonged weaning, 9 studies analyzed risk factors of weaning failure. The concrete definitions of these outcomes varied considerably between studies. For PMV, a variety of risk factors were identified, including comorbidities, site of intubation, various laboratory or blood gas parameters, ventilator settings, functional parameters, and critical care scoring systems. The risk of weaning failure was mainly related to age, previous home mechanical ventilation (HMV), cause of ventilation, and preexisting underlying diseases. Elevated PaCO2 values during spontaneous breathing trials were indicative of prolonged weaning and weaning failure.

CONCLUSION

A direct comparison of risk factors was not possible because of the heterogeneity of the studies. The large number of different definitions and relevant parameters reflects the heterogeneity of patients undergoing PMV and those discharged to HMV after unsuccessful weaning. Multidimensional scores are more likely to reflect the full spectrum of patients ventilated in different ICUs than single risk factors.

[An exploratory cross-sectional study on technical affinity and smartphone use among practice staff and patients: development of an app for multimorbid patients in general practice]

INTRODUCTION

Due to individual care needs, the provision of care to patients with two or more chronic diseases (multimorbidity) is described as complex. In addition, the number of chronically ill people is increasing, due in part to demographic changes which pose a challenge, especially for outpatient primary care. In order to fulfil patients' needs and to promote self-management as a central care element of chronically ill patients, the use of eHealth applications increases. TelePraCMan will be developed as one of these applications and includes a symptom-based electronic diary, which will be implemented in the established German disease management programme 'PraCMan'. This study is conducted as a part of the TelePraCMan project and aims to detect the needs of potential end users (physicians, medical assistants, patients).

METHODS

In the TelePraCMan development phase, an explorative cross-sectional study was conducted with potential end users of the TelePraCMan app (patients, physicians and medical assistants). For this purpose, a written survey was conducted in Baden-Wurttemberg between April 2019 and March 2020. The survey covered smartphone usage behaviour, technology affinity using the standardised questionnaire TA-EG, support network for technical questions and sociodemographic data.

RESULTS

A total of n=202 patients (n=98), physicians (n=58) and medical assistants (n=43) participated in the survey. Concerning smartphone use, 78.2 % of the participants stated that the function used most frequently was writing short messages. Health apps were the least used function (9.6 %). Furthermore, patients (12.6 %) use health apps more often than medical assistants (10.3%) and doctors (4.4 %). Participants aged 50 and younger were found to have a higher affinity for technology (mean=3.20, SD=0.51) than participants over 50 years of age (mean=2.98, SD=0.67). Older, multimorbid respondents had a particularly low affinity for technology (mean=2.52, SD=0.69). 10.9 % of the over-fifties and 12.5 % of the multimorbid persons felt able to fix any technical problems on their own without help. Multimorbid participants over the age of 50 were observed to prefer personal support over internet-based support.

DISCUSSION

On average, multimorbid respondents in the age group over 50 have a lower affinity for technology than respondents aged under 50 without multimorbidity. The most frequent negative attitude towards electronic devices is also found among patients over 50 years of age, who are expected to be the main target group of the TelePraCMan app. These findings can be used to derive requirements for the design and development of functions of the app, as well as accompanying measures, such as intuitive and simple user interface, a telephone hotline to support users, close consultation with users on the planned functions, and more.

CONCLUSION

Based on this survey, we were able to determine the needs of the future target group of the TelePraCMan app. This is seen as a starting point for the development of an implementation strategy and the pilot testing of the app in primary care.

Data blinding for the nEDM experiment at PSI

Psychological bias towards, or away from, prior measurements or theory predictions is an intrinsic threat to any data analysis. While various methods can be used to try to avoid such a bias, e.g. actively avoiding looking at the result, only data blinding is a traceable and trustworthy method that can circumvent the bias and convince a public audience that there is not even an accidental psychological bias. Data blinding is nowadays a standard practice in particle physics, but it is particularly difficult for experiments searching for the neutron electric dipole moment (nEDM), as several cross measurements, in particular of the magnetic field, create a self-consistent network into which it is hard to inject a false signal. We present an algorithm that modifies the data without influencing the experiment. Results of an automated analysis of the data are used to change the recorded spin state of a few neutrons within each measurement cycle. The flexible algorithm may be applied twice (or more) to the data, thus providing the option of sequentially applying various blinding offsets for separate analysis steps with independent teams. The subtle manner in which the data are modified allows one subsequently to adjust the algorithm and to produce a re-blinded data set without revealing the initial blinding offset. The method was designed for the 2015/2016 measurement campaign of the nEDM experiment at the Paul Scherrer Institute. However, it can be re-used with minor modification for the follow-up experiment n2EDM, and may be suitable for comparable projects elsewhere.

The role of personalised professional relations across care sectors in achieving high continuity of care

Background

High continuity of care has a positive impact on health outcomes, but insight into the mechanisms underlying this impact is limited. Information continuity, on which our study focuses, is especially important when relational continuity is not given, which is often the case at hospital admission or hospital discharge. The aim of this study is to provide insight into the information flows between general practices and hospitals in Germany, and to identify factors associated with these flows of information.

Methods

This is a qualitative interview study in a purposeful sample of staff from hospitals and general practices (general practitioners, care assistants in general practice, hospital management, hospital physicians, and nursing staff). Interviews were conducted via telephone or face-to-face using a self-developed semi-structured interview guide. Stepwise systematic content analysis was used to structure collected material into themes and sub-themes that related to the study aim. Data was analysed by two researchers in several cycles, alternating between inductive and deductive approaches.

Results

A total of 49 interviews were conducted. Duration of the interviews varies between 21 and 78 min (mean duration 43 min). Across all groups, more than two thirds of participants were female (n = 34, 69%). The analysis highlighted six interdependent main themes regarding factors that affect information flows between hospitals and general practices: organisational, legal, financial, patient factors, individual characteristics, and emotional & social factors. The latter theme emerged as particularly rich and was therefore divided into four subthemes: appreciation and understanding of the respective other, (intrinsic) motivation, socialisation, and relationships. Organised meetings and events were mentioned as strategies to address emotional and social factors.

Conclusions

Digitalisation can facilitate information flows between care providers. However, knowing each other and good personal relations remain important for effective collaboration. Cooperation between all stakeholders is needed to aim to achieve continuity of care.

Trial registration: DRKS00015183 on DRKS/ Universal Trial Number (UTN): U1111-1218–0992. Date of registration 23/08/2018.

A New Method for Structured Integration of User Needs in Two Health Technology Development Projects: Action Sheets

An early integration of users and stakeholders is needed for a successful innovation process. Nonetheless, the integration of users is often hard to realize - especially when dealing with persons with chronic diseases. In addition, patients or users in general often are not able to formulate the requirements in a technical manner. Therefore, even if user requirements are collected, it is not certain that the developers know or understand 'what is really wanted'. To overcome these 'gaps', we have developed so-called Action Sheets (AS). This article presents the use of AS in two projects: the development of health technologies for people with cancer (INFOPAT) and dementia (QuartrBack). Depending on the project context, group sessions were conducted with different stakeholders to identify the needs of (potential) users. Within the INFOPAT project, ten focus groups were conducted with patients, physicians and other healthcare professionals. In QuartrBack stakeholders like e.g. care professionals, technical assistance organizations and citizens participated in two focus groups and three world cafés. Their requirements were then 'fed' into the technology development by the use of AS. AS appear to be a promising tool to make user needs based on social values more tangible and implementable into technology development processes. In addition, it shows up that four phases seem to be necessary for transferring identified user and stakeholder needs into AS, which can therefore be seen as essential to translate non-technically formulated requirements into technically feasible ones. The case study shows as lessons learned that despite the successful integration of user needs, context-sensitive adjustments are still necessary.

Caregivers' role in using a personal electronic health record: a qualitative study of cancer patients and caregivers in Germany

Background

Particularly in the context of severe diseases like cancer, many patients wish to include caregivers in the planning of treatment and care. Many caregivers like to be involved but feel insufficiently enabled. This study aimed at providing insight into patients’ and caregivers’ perspectives on caregivers’ roles in managing the patient portal of an electronic personal health record (PHR).

Methods

A descriptive qualitative study was conducted comprising two study phases: (1) Usability tests and interviews with patients with cancer and caregivers (2) additional patient interviews after a 3-month-pilot-testing of the PHR. For both study parts, a convenience sample was selected, focusing on current state of health and therapy process and basic willingness to participate and ending up with a mixed sample as well as saturation of data. All interviews were audio-recorded, pseudonymized, transcribed verbatim and qualitatively analyzed.

Results

Two main categories emerged from qualitative data: ‘Caregivers’ role’ and ‘Graduation of access rights’ – consisting of four subcategories each. The interviewed patients (n = 22) and caregivers (n = 9) felt that the involvement of caregivers is central to foster the acceptance of a PHR for cancer patients. However, their role varied from providing technical support to representing patients, e.g. if the patient’s state of health made this necessary. Heterogeneous opinions emerged regarding the question whether caregivers should receive full or graduated access on a patient’s PHR.

Conclusions

In order to support the patient and to participate in the care process, caregivers need up-to-date information on the patient’s health and treatment. Nevertheless, some patients do not want to share all medical data with caregivers, which might strain the patient-caregiver relationship. This needs to be considered in development and implementation of personal health records. Generally, in the debate on patient portals of a personal health record, paying attention to the role of caregivers is essential. By appreciating the important relationship between patients and caregivers right from the beginning, implementation, of a PHR would be enhanced.

Trial registration

ISRCTN85224823. Date of registration: 23/12/2015 (retrospectively registered).

An Electronic Medication Module to Improve Health Literacy in Patients With Type 2 Diabetes Mellitus: Pilot Randomized Controlled Trial

Background

In primary care, patients play a crucial role in managing care processes and handling drug treatment. A decisive factor for success is their health literacy, and several interventions have been introduced to support patients in fulfilling their responsibility.

Objective

The aim of this study is to assess the influence of such an intervention (ie, a medication module) within a patient-led electronic health record on patients’ health literacy.

Methods

We conducted a randomized controlled study among community-dwelling patients with type 2 diabetes mellitus. Patients were recruited from primary care practices. After randomization, patients either had access to an internet-based medication module allowing them to store their medication information, look up drug information, and print a medication schedule (intervention group), or they received an information brochure on the importance of medication schedules (control group). After 4-8 weeks, all patients were invited to attend a structured medication review (ie, follow-up visit). Data were collected via questionnaires before the start of the intervention and during the follow-up visit. The main outcome measure was the mean difference in health literacy between baseline and follow-up assessments of patients in the control and intervention groups.

Results

Of 116 recruited patients, 107 (92.2%) completed the follow-up assessment and were eligible for intention-to-treat analyses. Only 73 patients, of which 29 were in the intervention group, followed the study protocol and were eligible for per-protocol analysis. No differences in overall health literacy were observed in either the intention-to-treat or in the per-protocol cohorts. Reasons for a null effect might be that the cohort was not particularly enriched with participants with low health literacy, thus precluding measurable improvement (ie, ceiling effect). Moreover, the success of implementation was considered poor because both the correct application of the study procedure (ie, randomization according to the protocol and dropout of 29 patients) and the actual interaction with the medication module was modest (ie, dropout of 9 patients).

Conclusions

The conduct of this randomized controlled study was challenging, leaving it open whether inadequate implementation, too short of a duration, or insufficient efficacy of the intervention, as such, contributed to the null effect of this study. This clearly outlines the value of piloting complex interventions and the accompanying process evaluations.

Measurement of the Permanent Electric Dipole Moment of the Neutron

We present the result of an experiment to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute using Ramsey's method of separated oscillating magnetic fields with ultracold neutrons. Our measurement stands in the long history of EDM experiments probing physics violating time-reversal invariance. The salient features of this experiment were the use of a ^{199}Hg comagnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic-field changes. The statistical analysis was performed on blinded datasets by two separate groups, while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is d_{n}=(0.0±1.1_{stat}±0.2_{sys})×10^{-26}  e.cm.

nEDM experiment at PSI: Data-taking strategy and sensitivity of the dataset

We report on the strategy used to optimize the sensitivity of our search for a neutron electric dipole moment at the Paul Scherrer Institute. Measurements were made upon ultracold neutrons stored within a single chamber at the heart of our apparatus. A mercury cohabiting magnetometer together with an array of cesium magnetometers were used to monitor the magnetic field, which was controlled and shaped by a series of precision field coils. In addition to details of the setup itself, we describe the chosen path to realize an appropriate balance between achieving the highest statistical sensitivity alongside the necessary control on systematic effects. The resulting irreducible sensitivity is better than 1 × 10−26e cm. This contribution summarizes in a single coherent picture the results of the most recent publications of the collaboration.

The n2EDM experiment at the Paul Scherrer Institute

We present the new spectrometer for the neutron electric dipole moment (nEDM) search at the Paul Scherrer Institute (PSI), called n2EDM. The setup is at room temperature in vacuum using ultracold neutrons. n2EDM features a large UCN double storage chamber design with neutron transport adapted to the PSI UCN source. The design builds on experience gained from the previous apparatus operated at PSI until 2017. An order of magnitude increase in sensitivity is calculated for the new baseline setup based on scalable results from the previous apparatus, and the UCN source performance achieved in 2016.

Conductance Spectroscopy of Exfoliated Thin Flakes of Nb xBi2Se3

We study unconventional superconductivity in exfoliated single crystals of a promising three-dimensional (3D) topological superconductor candidate, Nb-doped Bi₂Se₃ through differential conductance spectroscopy and magneto-transport. The strong anisotropy of the critical field along the out-of-plane direction suggests that the thin exfoliated flakes are in the quasi-2D limit. Normal metal-superconductor (NS) contacts with either high or low transparencies made by depositing gold leads onto Nb-doped Bi₂Se₃ flakes both show significant enhancement in zero bias conductance and coherence dips at the superconducting energy gap. Such behavior is inconsistent with conventional Blonder-Tinkham-Klapwijk theory. Instead, we discuss how our results are consistent with p-wave pairing symmetry, supporting the possibility of topological superconductivity in Nb-doped Bi₂Se₃. Finally, we observe signatures of multiple superconducting energy gaps, which could originate from multiple Fermi surfaces reported earlier in bulk crystals.

An arbitrary-function light power controller

We describe the design, applications, and performance of a simple light power controller. The device is built on a fiber-coupled electro-optic modulator with an active electronic feedback. It can be used to actively stabilize laser power or to impress an arbitrary waveform onto the power. The bandwidth of the device is ∼70 kHz.

Observation of Gravitationally Induced Vertical Striation of Polarized Ultracold Neutrons by Spin-Echo Spectroscopy

We describe a spin-echo method for ultracold neutrons (UCNs) confined in a precession chamber and exposed to a |B0|=1  μT magnetic field. We have demonstrated that the analysis of UCN spin-echo resonance signals in combination with knowledge of the ambient magnetic field provides an excellent method by which to reconstruct the energy spectrum of a confined ensemble of neutrons. The method takes advantage of the relative dephasing of spins arising from a gravitationally induced striation of stored UCNs of different energies, and also permits an improved determination of the vertical magnetic-field gradient with an exceptional accuracy of 1.1  pT/cm. This novel combination of a well-known nuclear resonance method and gravitationally induced vertical striation is unique in the realm of nuclear and particle physics and should prove to be invaluable for the assessment of systematic effects in precision experiments such as searches for an electric dipole moment of the neutron or the measurement of the neutron lifetime.

Highly stable atomic vector magnetometer based on free spin precession

We present a magnetometer based on optically pumped Cs atoms that measures the magnitude and direction of a 1 μT magnetic field. Multiple circularly polarized laser beams were used to probe the free spin precession of the Cs atoms. The design was optimized for long-time stability and achieves a scalar resolution better than 300 fT for integration times ranging from 80 ms to 1000 s. The best scalar resolution of less than 80 fT was reached with integration times of 1.6 to 6 s. We were able to measure the magnetic field direction with a resolution better than 10 μrad for integration times from 10 s up to 2000 s.

Spectroscopy of Mn atoms isolated in solid ⁴He

We present an experimental study of the laser-induced luminescence spectra of Mn atoms in solid helium matrices. We observe transitions of the valence electron and of inner-shell electrons. We find that the Mn-He interaction perturbs the inner-shell transitions to a lesser extent than the valence-electron transitions. The observed lineshapes of the inner-shell transitions of Mn are similar to those of an inner-shell transition in Ba studied earlier. At the same time, they are more strongly perturbed than the corresponding transitions in Au and Cu under the same conditions. We suggest a qualitative explanation of these observations based on the atomic bubble model. Our results also suggest that the inner-shell transitions of Mn in solid He are more strongly perturbed than the same lines of Mn isolated in solid Ar or Kr matrices.

Spectroscopy of gold atoms isolated in liquid and solid 4He matrices

We present a systematic experimental study of absorption and fluorescence spectra of Au atoms in bulk liquid and solid helium matrices. The results are compared to the spectra of Cu atoms studied earlier. We investigate the dependence of the observed spectral lineshapes on the helium pressure. The observed splitting of the 5d(10)6p - 5d(9)6s(2) transitions of Au in hcp solid He gives evidence for an anisotropic trapping site structure formed either by a non-spherical atomic bubble or a four-vacancy center.

A Bell-Bloom experiment with polarization-modulated light of arbitrary duty cycle

We report on a study of polarization-modulation experiments on the 4 → 3 hyperfine component of the D1 transition in Cs vapor contained in a paraffin-coated cell. The laser beam's polarization was switched between left- and right-circular polarization at a rate of 200 Hz. Variations of the transmitted light power were recorded while varying the amplitude of a transverse magnetic field. The power shows electromagnetically induced transparency (EIT) resonances when the atomic Larmor frequency matches a harmonic of the modulation frequency. We made a quantitative study of the resonance amplitudes with square-wave modulations of various duty cycles, and find an excellent agreement with recent algebraic model predictions.

Spectroscopy of Cs2, RbCs, and Rb2 in solid 4He

We present comparative experimental and theoretical studies of the absorption and fluorescence spectra of the alkali-metal dimer molecules Cs(2) and RbCs immersed in a solid helium matrix, thereby extending our recent observations of Rb(2) in solid (4)He. The laser-excited molecular states are mostly quenched by the interaction with the He matrix. The quenching efficiently populates the second lowest excited state of the molecule, i.e., (1)  (3)Π((u)) that is metastable in the homonuclear dimers. Molecular excitation and emission bands are modeled by calculating Franck-Condon factors that give a reasonable agreement with the experimental findings.

Test of Lorentz invariance with spin precession of ultracold neutrons

A clock comparison experiment, analyzing the ratio of spin precession frequencies of stored ultracold neutrons and 199Hg atoms, is reported. No daily variation of this ratio could be found, from which is set an upper limit on the Lorentz invariance violating cosmic anisotropy field b perpendicular < 2 x 10(-20) eV (95% C.L.). This is the first limit for the free neutron. This result is also interpreted as a direct limit on the gravitational dipole moment of the neutron |gn| < 0.3 eV/c2 m from a spin-dependent interaction with the Sun. Analyzing the gravitational interaction with the Earth, based on previous data, yields a more stringent limit |gn| < 3 x 10(-4) eV/c2 m.

Positive ion induced solidification of 4He

We have observed bulk solidification of 4He induced by nucleation on positive alkali ions in pressurized superfluid helium. The ions are extracted into the liquid from alkali-doped solid He by a static electric field. The experiments prove the existence of charged particles in a solid structure composed of doped He that was recently shown to coexist with superfluid helium below the He solidification pressure. This supports our earlier suggestion that the Coulomb interaction of positive ions surrounded by a solid He shell (snowballs) and electrons trapped in spherical cavities (electron bubbles), together with surface tension, is responsible for the stability of that structure against melting. We have determined the density of charges in the sample by two independent methods.

Direct experimental limit on neutron-mirror-neutron oscillations

In case a mirror world with a copy of our ordinary particle spectrum would exist, the neutron n and its degenerate partner, the mirror neutron n', could potentially mix and undergo nn' oscillations. The interaction of an ordinary magnetic field with the ordinary neutron would lift the degeneracy between the mirror partners, diminish the n' amplitude in the n wave function and, thus, suppress its observability. We report an experimental comparison of ultracold neutron storage in a trap with and without superimposed magnetic field. No influence of the magnetic field is found and, assuming negligible mirror magnetic fields, a limit on the oscillation time taunn' > 103 s (95% C.L.) is derived.

Administration of 6-methoxybenzoxazolinone (MBOA) does not augment ovulatory responses in St. Croix White ewes superovulated with PMSG

The objective of this investigation was to examine the effects of 6-methoxy-benzoxazolinone (MBOA), a plant compound that resembles melatonin and alters ovarian function in rodents, in combination with PMSG on superovulatory responses in the cycling ewe. In Experiment I, St. Croix White ewes (n = 44) were synchronized (intra-vaginal progestin sponge) for 14days followed by hCG (750 IU) at 1 day after sponge removal (day 0). Ewes were assigned to one of six treatments administered on day -1: Control (no PMSG or MBOA; n = 7); PMSG (1000 IU i.m.; n = 7); Low MBOA (0.43 mg/kg i.m.; n = 7); High MBOA (1.15 mg/kg i.m.; n = 7); Low MBOA + PMSG (n = 8); High MBOA + PMSG (n = 8). In Experiment II, St. Croix White ewes (n = 24) were synchronized (progestin CIDR) for 14 days followed by hCG on day 1 after CIDR removal (day 0). Ewes were assigned to one of three treatments administered on day -1: Control (n = 8); PMSG (n = 8); Low MBOA+PMSG (n = 8). Laparoscopy was performed on day 9 to assess numbers of corpora lutea (CL) and visible follicles on each ovary. Blood samples were collected on day -13, -1, 0, 1, and days 6 or 7-12 for analysis of serum progesterone (P4) by RIA. Treatment groups receiving PMSG (alone or with MBOA) exhibited greater (P < 0.05) serum concentrations of P4 post-synchrony than Control and MBOA-only groups. Ovulation rate was lower (P < 0.05) for Control and MBOA-only treated ewes than ewes receiving PMSG. Ovulation rate in ewes treated with MBOA alone was similar (P > 0.10) to Controls, and PMSG treatment alone did not differ (P > 0.10) from MBOA + PMSG treatment. Ewes treated with PMSG alone did not differ (P > 0.10) in follicle number from High MBOA + PMSG treated ewes, however, Low MBOA + PMSG treated ewes had greater numbers of follicles at day 9 (P < 0.05) than the PMSG or High MBOA + PMSG groups in Experiment I; although, this was not replicated in Experiment II with numbers of follicles in the Low MBOA + PMSG group being similar (P > 0.10) to PMSG alone. In summary, the addition of MBOA in combination with PMSG as part of a synchronization-superovuation protocol in the ewe did not increase ovulation rate.

Cs*Hen exciplexes in solid He4

We present a theoretical and experimental study of the laser-induced formation process and of the emission spectra of Cs*He(n) exciplexes in the hcp and bcc phases of solid helium. Two different exciplex molecules are detected: a linear triatomic Cs*He2, which can exist in two electronic states: APi(1/2) and BPi(3/2), and a larger complex, where six or seven He atoms form a ring around a single cesium atom in the 6P(1/2) state. A theoretical model is presented, which allows the interpretation of the experimentally observed spectra.

Design and Performance of Laser-Pumped Cs-Magnetometers for the Planned UCN EDM Experiment at PSI

We designed laser-pumped cesium vapor magnetometers in the M x configuration for the control and stabilization of magnetic field fluctuations and gradients in a new experiment searching for a permanent electric dipole moment of the neutron. The intrinsic sensitivity of the device was determined to be 30 fT in a measurement bandwidth of 1 Hz, limited by laser noise. In the shot noise limit the magnetometer can reach a sensitivity of 7 fT for 1 s integration time. Test measurements of the stability of a 2 µT magnetic field in a threefold magnetic shield have revealed fluctuations on the order of 200 fT to 300 fT with integration times in the range of 2 s to 100 s. Those fluctuations were traced back to the stability of the power supply used to generate the magnetic field. The laser-pumped magnetometer fulfills the requirements set by the planned neutron electric dipole moment experiment.

Discovery of dumbbell-shaped Cs*Hen exciplexes in solid 4He

We have observed several new spectral features in the fluorescence of cesium atoms implanted in the hcp phase of solid helium following laser excitation to the 62P states. Based on calculations of the emission spectra using semiempirical Cs-He pair potentials the newly discovered lines can be assigned to the decay of specific Cs*Hen exciplexes: an apple-shaped Cs(APi3/2)He2 and a dumbbell-shaped Cs(APi1/2)Hen exciplex with a well-defined number n of bound helium atoms. While the former has been observed in other environments, it was commonly believed that exciplexes with n>2 might not exist. The calculations suggest Cs(APi1/2)He7 to be the most probable candidate for that exciplex, in which the helium atoms are arranged on a ring around the waist of the dumbbell-shaped electronic density distribution of the cesium atom.

Dynamical MCG mapping with an atomic vapor magnetometer

We have developed a magnetometer based on magnetic resonance in cesium vapor optically pumped by resonant laser radiation, which has the sensitivity and bandwidth to record human magnetocardiograms. The device is operated as a first-order gradiometer in a weakly shielded environment and allows us to record 2-dimensional field maps by shifting the subject with respect to a single sensor and making time-sequential measurements. We discuss the magnetometer technique and its performance as well as obtained results, which include a comparison of MCG data recorded with our single channel optical magnetometer with SQUID measurements from a commercial multi-channel device as well as from SQUID reference data. The results obtained so far in the detection of cardiomagnetic signals using the optical magnetometer make us confident that the technique has a high potential to serve as an alternative to SQUID detection.

Dynamical mapping of the human cardiomagnetic field with a room-temperature, laser-optical sensor

The magnetic field produced by the human heart carries valuable information for medical research, as well as for diagnostics and screening for disease. We have developed an optical method that allows us to produce movies of the temporal dynamics of the human cardiomagnetic field map. While such movies have been generated before with the help of SQUIDmagnetometers, our technique operates at room temperature and promises substantial economic advantages.

Diagnostic value of bone and tumour markers in patients with malignant diseases

INTRODUCTION

Biochemical bone markers, such as the bone isoenzyme form of alkaline phosphatase, have been used to assess the bone formation phase of bone turnover in health and disease. Skeletal metastases often occur in patients with malignancies. Recent developments suggest that bone markers could be valuable clinical tools for the management of patients with metastatic bone disease.

PATIENTS AND METHODS

Serum levels of BAP, along with serum levels of beta-CrossLap, were measured in a large group (n = 200) of patients with newly-diagnosed or progressive cancer of the prostate, breast, colon, liver and pancreas. Tumour markers such as PSA, CEA, CA 19-9, AFP, CA 15-3 and bone marker levels were correlated with the presence or absence of bone scan-documented metastases.

RESULTS

Both of the bone markers examined were elevated in a high proportion of patients with confirmed metastases to bone. All patients with prostate, breast and colon carcinoma showed elevated beta-CrossLap values. The determined values of beta-CrossLap and BAP were significantly correlated with the number of skeletal metastases.

CONCLUSION

Markers of biochemical bone remodeling can be used in assessing and managing patients with malignancies that metastasize to bone. These markers are abnormally raised in the blood of patients with metastatic bone disease.

Optical detection of nonradiating alkali atoms in solid helium

We have detected by optical means nonfluorescing 85Rb and 87Rb atoms implanted in a body centered cubic 4He crystal. In contrast to cesium the resonance fluorescence of rubidium is strongly quenched by the helium matrix, and the weak resonance absorption of the two Rb isotopes was detected using a double resonance technique. From a comparative study of the (optically detected) magnetic resonance spectra of 85Rb, 87Rb, and 133Cs we infer their effective g(F) factors and conclude that they are not perturbed by the He matrix at a level of 2 x 10(-4). We show further that optical pumping of Rb proceeds via depopulation, whereas for Cs it proceeds via repopulation.

Endosonography of insulin-secreting and clinically non-functioning neuroendocrine tumors of the pancreas: criteria for benignancy and malignancy

OBJECTIVE

Endosonography is a powerful tool in the diagnosis of gastroenteropancreatic neuroendocrine tumors. This study was performed in order to characterize endosonographic criteria of malignant and benign neuroendocrine pancreatic tumors focussing on those typically presented to endocrinologists, i.e. insulin-secreting tumors and clinically non-functioning tumors in MEN-1.

DESIGN

We studied six benign insulinomas, four hormone inactive benign neuroendocrine adenomas in MEN-1, and three non-metastatic neuroendocrine carcinomas with clinically symptomatic insulin secretion.

METHODS

Endosonography was performed using Pentax FG 32 UA endosonoscope with a longitudinal 7.5 MHz sector array.

RESULTS

Tumor diameter was larger in malignant tumors (19 - 70 / 47.0 +/- 25.9 mm) than in benign lesions (2.3 - 19 / 9.7 +/- 5.8 mm). Hypoechoic echogeneity was more or less present in benign and in malignant tumors and could not be used as a criteria for differential diagnosis. Heterogeneous or multinodular structure on endosonographic imaging however, was an exclusive feature of malignant tumors. Echo-free areas representing cystic transformation or necrosis and vascular invasion were additional signs of malignancy.

CONCLUSIONS

Molecular genetic diagnosis of MEN-1 and new therapeutic developments such as endoscopic surgery make sufficient imaging procedures in the management of neuroendocrine pancreatic tumors mandatory. Besides valid detection and exact localization, endosonography provides criteria for benign and malignant tumors and thus may be helpful in planning therapeutic strategies.