In vivo stability of ester- and ether-linked phospholipid-containing liposomes as measured by perturbed angular correlation spectroscopy

To evaluate liposome formulations for use as intracellular sustained-release drug depots, we have compared the uptake and degradation in rat liver and spleen of liposomes of various compositions, containing as their bulk phospholipid an ether-linked phospholipid or one of several ester-linked phospholipids, by perturbed angular correlation spectroscopy. Multilamellar and small unilamellar vesicles (MLVs and SUVs), composed of egg phosphatidylcholine, sphingomyelin, distearoyl phosphatidylcholine (DSPC), dipalmitoyl phosphatidylcholine (DPPC) or its analog dihexadecylglycerophosphorylcholine (DHPC), and cholesterol plus phosphatidylserine, and containing (111)In complexed to nitrilotriacetic acid, were injected intravenously in rats. Recovery of (111)In-labeled liposomes in blood, liver, and spleen was assessed at specific time points after injection and the percentage of liposomes still intact in liver and spleen was determined by measurement of the time-integrated angular perturbation factor ([G22(∞)] of the (111)In label. We found that MLVs but not SUVs, having DHPC as their bulk phospholipid, showed an increased resistance against lysosomal degradation as compared to other phospholipid-containing liposomes. The use of diacyl phospholipids with a high gel/liquid-crystalline phase-transition temperature, such as DPPC and DSPC, also retarded degradation of MLV, but not of SUV in the dose range tested, while the rate of uptake of these liposomes by the liver was lower

Interactions between wild oat and a weed-competitive and non-competitive wheat cultivar as influenced by arbuscular mycorrhizal fungi

Non-Peer ReviewedThe response of a weed-competitive (Columbus) and non-competitive (Oslo) wheat (Triticum aestivum L.) cultivar, alone and in competition with wild oat (Avena fatua L.) to arbuscular mycorrhizal fungi (AMF) was assessed in a greenhouse study using four AMF species. Plants were inoculated with 300 spores of Glomus clarum, G. etunicatum, G. intraradices or G. mosseae and grown for 77 d in field soil containing low levels of indigenous AMF populations. The AMF species had no significant (P<0.05) effect on the shoot fresh or dry weight of single stands of Oslo or Columbus compared to the uninoculated controls. However, G. etunicatum significantly (P<0.05) enhanced the shoot fresh weight of single stands of wild oat, and G. intraradices significantly (P<0.05) increased the shoot fresh and dry weight of wild oat compared to the uninoculated control. The competitiveness of wild oat in competition with Oslo was significantly (P<0.05) enhanced by inoculation with G. mosseae, whereas the other AMF species had no effect. In contrast, inoculation of Oslo with G. clarum significantly (P<0.05) increased the ability of Oslo to withstand wild oat competition. On the other hand, there were no differences in the ability of any of the AMF species to impact on wild oat growth in competition with Columbus. However, G. intraradices significantly (P<0.05) increased the shoot dry weight of Columbus in competition with wild oat. These preliminary results indicate that different AMF species interact differently with various hosts, and that these interactions may be specific. In addition, it is apparent that these specific interactions may enhance the competitiveness of a non-competitive host against weeds

Psychosomatic Rehabilitation Patients and the General Population During COVID-19: Online Cross-sectional and Longitudinal Study of Digital Trainings and Rehabilitation Effects.

BACKGROUND: The COVID-19 pandemic has largely affected people's mental health and psychological well-being. Specifically, individuals with a pre-existing mental health disorder seem more impaired by lockdown measures posing as major stress factors. Medical rehabilitation treatment can help people cope with these stressors. The internet and digital apps provide a platform to contribute to regular treatment and to conduct research on this topic. OBJECTIVE: Making use of internet-based assessments, this study investigated individuals from the general population and patients from medical, psychosomatic rehabilitation clinics. Levels of depression, anxiety, loneliness, and perceived stress during the COVID-19 pandemic, common COVID-19-related worries, and the intention to use digital apps were compared. Furthermore, we investigated whether participating in internet-delivered digital trainings prior to and during patients' rehabilitation stay, as well as the perceived usefulness of digital trainings, were associated with improved mental health after rehabilitation. METHODS: A large-scale, online, cross-sectional study was conducted among a study sample taken from the general population (N=1812) in Germany from May 2020 to April 2021. Further, a longitudinal study was conducted making use of the internet among a second study sample of psychosomatic rehabilitation patients at two measurement time points-before (N=1719) and after (n=738) rehabilitation-between July 2020 and April 2021. Validated questionnaires and adapted items were used to assess mental health and COVID-19-related worries. Digital trainings were evaluated. Propensity score matching, multivariate analyses of covariance, an exploratory factor analysis, and hierarchical regression analyses were performed. RESULTS: Patients from the psychosomatic rehabilitation clinics reported increased symptoms with regard to depression, anxiety, loneliness, and stress (F4,2028=183.74, P<.001, η2p=0.27) compared to the general population. Patients perceived greater satisfaction in communication with health care professionals (F1,837=31.67, P<.001, η2p=0.04), had lower financial worries (F1,837=38.96, P<.001, η2p=0.04), but had higher household-related worries (F1,837=5.34, P=.02, η2p=0.01) compared to the general population. Symptoms of depression, anxiety, loneliness, and perceived stress were lower postrehabilitation (F1,712=23.21, P<.001, η2p=0.04) than prior to rehabilitation. Psychosomatic patients reported a higher intention to use common apps and digital trainings (F3,2021=51.41, P<.001, η2p=0.07) than the general population. With regard to digital trainings offered prior to and during the rehabilitation stay, the perceived usefulness of digital trainings on rehabilitation goals was associated with decreased symptoms of depression (β=-.14, P<.001), anxiety (β=-.12, P<.001), loneliness (β=-.18, P<.001), and stress postrehabilitation (β=-.19, P<.001). Participation in digital group therapy for depression was associated with an overall change in depression (F1,725=4.82, P=.03, η2p=0.01) and anxiety (F1,725=6.22, P=.01, η2p=0.01) from pre- to postrehabilitation. CONCLUSIONS: This study validated the increased mental health constraints of psychosomatic rehabilitation patients in comparison to the general population and the effects of rehabilitation treatment. Digital rehabilitation components are promising tools that could prepare patients for their rehabilitation stay, could integrate well with face-to-face therapy during rehabilitation treatment, and could support aftercare. TRIAL REGISTRATION: ClinicalTrials.gov NCT04453475; https://clinicaltrials.gov/ct2/show/NCT04453475 and ClinicalTrials.gov NCT03855735; https://clinicaltrials.gov/ct2/show/NCT03855735

Standard model plethystics

We study the vacuum geometry prescribed by the gauge invariant operators of the minimal supersymmetric standard model via the plethystic program. This is achieved by using several tricks to perform the highly computationally challenging Molien-Weyl integral, from which we extract the Hilbert series, encoding the invariants of the geometry at all degrees. The fully refined Hilbert series is presented as the explicit sum of 1422 rational functions. We found a good choice of weights to unrefine the Hilbert series into a rational function of a single variable, from which we can read off the dimension and the degree of the vacuum moduli space of the minimal supersymmetric standard model gauge invariants. All data in Mathematica format are also presented

Distress, loneliness, and mental health during the COVID-19 pandemic: Test of the extension of the Evolutionary Theory of Loneliness.

COVID-19 restrictions such as lockdowns or quarantines may increase the risk for social isolation and perceived loneliness. The mechanisms can be modeled by Cacioppo's Evolutionary Theory of Loneliness (ETL), which predicts that a lack of perceived social connectedness may lead, in the long-term, to mental and physical health consequences. However, the association between COVID-19 pandemic distress, mental health, and loneliness is not sufficiently understood. The present longitudinal study examined the relationship between distress and depression, and the mediating effects of anxiety and loneliness in a German rehabilitation sample (N = 403) at two timepoints (≤6 weeks pre-rehabilitation; ≥12 weeks post-rehabilitation; mean time between T1 and T2 was  52 days). Change scores between T1 and T2 were examined for the variables COVID-19 Peritraumatic Distress Index (CPDI), anxiety, loneliness, and depression. The results of the serial mediation analysis indicated that anxiety and loneliness were able to explain the relationship between distress and depression with 42% of variance in depression accounted for. Findings extend research on the relationship between COVID-19 and mental health by considering anxiety and loneliness as sustaining factors of depressive symptoms, thus, successfully applying the ETL. Results stress the necessity to consider anxiety and loneliness in the treatment or prevention of depression

Psychological Intervention to Improve Communication and Patient Safety in Obstetrics: Examination of the Health Action Process Approach.

BACKGROUND: Human failure and a lack of effective communication are the main reasons for preventable adverse events, compromising patient safety in obstetrics. In order to improve safety, team and communication interventions have been implemented but lack feasibility in obstetric care. Psychological models such as the health action process approach might help to improve interventions. METHODS: In a cross-sectional online survey with N = 129 healthcare workers (Study 1) and a paper-pencil survey with N = 137 obstetric healthcare workers at two obstetric university hospitals (Study 2), associations of social-cognitive variables were tested in a path analysis and a multiple regression. Preliminary results informed a communication training for all obstetric healthcare workers. A repeated-measures MANOVA was used to compare pre- and post-intervention data. RESULTS: Social-cognitive variables were associated according to model suggestions (β = -0.26 to 0.45, p < 0.05) except for planning in the first study. Triggers of adverse events were associated (β = -0.41 to 0.24, p < 0.05) with communication behavior (Study 2), action self-efficacy and planning (Study 1), as well as barriers to effective communication (both studies). The intervention was rated positively (M = 3.3/4). Afterward, fewer triggers were reported and coping self-efficacy increased. There were group differences regarding hospital, experience, and time. DISCUSSION: The health action process approach was examined in the context of safe communication in obstetrics and can be used to inform interventions. A theory-based, short training was feasible and acceptable. Perceived patient safety improved but communication behavior did not. Future research should aim to test a more comprehensive psychological communication intervention in a thorough RCT design

Assessment of Arctic seasonal snow cover rates of change

Arctic snow cover extent (SCE) trends and rates of change reported across recent climate assessments vary due to the time period of available data, the selection of snow products, and methodological considerations. While all reported trends are strongly negative during spring, more uncertainty exists in autumn. Motivated to increase the confidence in SCE trends reported in climate assessments, we quantify the impact of (1) year-over-year increases in time series length over the past 2 decades, (2) the choice of reference period, (3) the application of a statistical methodology to improve inter-dataset agreement, (4) the dataset ensemble size, and (5) product version changes. Results show that the rate of change during May and June has remained consistent over the past decade as time series length has increased and is largely insensitive to the choice of reference period. Although new product versions have increased spatial resolution, use more advanced reanalysis meteorology to force snow models, and include improved remote sensing retrieval algorithms, these enhancements do not result in any notable changes in the observed rate of Arctic SCE change in any month compared to a baseline set of older products. The most impactful analysis decision involves the scaling of dataset climatologies using an updated version of the NOAA snow chart climate data record as the baseline. While minor for most months, this adjustment can influence the calculated rate of change for June by a factor of 2 relative to different climatological baselines.</p