Limited Role Research Articles

Sequential pulmonary functions in survivors of leptospirosis pulmonary haemorrhage syndrome: a prospective cohort study

BackgroundLeptospirosis, a spirochaete infection, can lead to Leptospirosis Pulmonary Haemorrhage Syndrome (LPHS), which requires intensive care admission and has a high mortality. Although data on short-term outcomes are available, the long-term respiratory sequelae of LPHS survivors are not known. We aimed to identify the post-discharge pulmonary functions and functional limitations in survivors of LPHS.MethodsWe conducted a prospective cohort study from January to December 2022 at the Medical Intensive Care Unit (ICU) of the National Hospital of Sri Lanka to assess the sequential changes in the spirometry parameters in patients who survived LPHS. The Forced Vital Capacity (FVC) and Forced Expiratory Volume in 1 s (FEV1) were measured on the day of discharge from the ICU (D0), 7th day after discharge (D7) and 28th day after discharge (D28). The predicted lung volume was calculated using the gender, age and height as per standard protocol. Physical and functional role limitations were assessed on D28 using the modified Medical Outcomes Study Questionnaire Short Form 36 Health Survey (SF-36).ResultsTwenty-one patients with a mean age of 44 years (SD 16.07) were enrolled for the study. The majority were male patients (n = 19, 90.5%). Leptospirosis was serologically confirmed in all individuals. Seventeen (81%) patients had reduced FEV1 and FVC on D0, indicating a restrictive lung abnormality. FVC and FEV1 improved during the first 7 days (p < 0.01) but did not change significantly afterwards. Only seven individuals (33.3%) achieved a normal FVC (exceeding 80% of the predicted volume) at D28. However, 19 (90.5%) individuals achieved a normal FEV1 (exceeding 80% of predicted volume) by D28. In our study, administering corticosteroids during ICU stay did not impact lung recovery in FVC (p = 0.521) or FEV1 (p = 0.798). The participants did not have significant physical, functional, and role limitations at D28.ConclusionsThe spirometry measurements of individuals diagnosed with LPHS significantly improved during the first 7 days. Most survivors did not have a functional impairment despite the FVC not recovering to normal by D28.

Effects of the Change in Respiratory Kinematics on the Singing Voice: Re-Visiting the Benefits of Diaphragmatic-Abdominal Breathing in Professional Singers with Problems in Pitch.

Objectives: To assess the effect of voice therapy on pitch in professional singers with faulty respiratory kinematics. Methodology: In this prospective interventional study, professional singers with easy voice fatigability and inability to reach higher pitches, following appropriate selection criteria, were subjected to a 1-month structured voice therapy that transformed their predominant breathing pattern from thoracic to diaphragmatic-abdominal. Acoustic parameters (pitch range and its extreme values before/after therapy, and difference in pitch range) were analyzed using Praat software and compared using standard statistical methods (paired t-test). The singers' age and career duration were also correlated with the pitch parameters (Pearson's correlation coefficient). Results: The singers (n = 60; 55% men, 45% women; respective mean age: 34.24, 35.92 years; average singing career: 12.56 years) had thoracic breathing before treatment [average pitch-range: 92.8 Hz; 85.84 Hz (men), 101.29 Hz (women)] that turned to abdominal type post-therapy [average pitch-range: 189.21 Hz; 178.54 Hz (men), 202.25 Hz (women)]. The decrease in the mean lowest pitch was significant by paired t-test in both men and women (t = 7.96 and 7.87, respectively; .0001 significant level of test), as also the increase in mean highest pitch (t = 23.85 and 17.45, respectively; .0001 significant level of test) and change in pitch range (t = 19.45 and 17.37, respectively; .0001 significant level of test). Correlations between age/career duration with pitch range before and after therapy and its difference varied from very poor to fair [respectively, for men and women, age with pitch range: r = -.54, r = .03 (pre-therapy); r = .045, r = -.39 (post-therapy); age with difference in pitch range: r = .21, r = -.30; singing career with pitch-range: r = -.36, r = .25 (pre-therapy); r = .3, r = -.5 (post-therapy); singing career with difference in pitch range: r = .29, r = -.51]. Conclusions: Voice therapy directed to change respiratory kinematics from thoracic to diaphragmatic-abdominal was significant in the restoration of acoustic voice parameters in professional singers. Their age and duration of singing career had limited roles as adjuncts to voice therapy in the process.

Effects of Exercise and a Lifestyle App on Sleep-Disordered Breathing, Physical Health, and quality of Life

Background. Sleep-disordered breathing (SDB) is a growing public health problem, and non-invasive treatments may be a valid option. The objective of this randomized controlled trial was to assess the effects of a 12-week exercise program and a lifestyle app on SDB severity, physical health (anthropometry, body composition, physical fitness), and health-related quality of life (HRQoL) in 18–50 years old adults with mild-to-moderate SDB.Methods. One-hundred-ninety-two participants (age 37.4±6.3years, BMI 33.3±4.2kg·m−2, 52.6% males) with mild-to-moderate SDB (apnea-hypopnea index [AHI] ≥5&lt;30.0, objective snore ≥10%) were randomized into: Exercise (three times/week, 60 min), app, and control groups. The assessments included a three-night self-applied polysomnography, anthropometryt, body composition, physical fitness, and HRQoL. Repeated ANOVA, Wilcoxon signed-rank and Kruskal-Wallis test were used to evaluate the changes.Results. Time effect was observed in AHI (F=6.290, p=0.014), neck circumference (F=5.253, p=0.024), hand dynamometry (F=7.102, p=0.009), and 6-minute walking test (F=8.340, p=0.005). Group x time interactions were observed in weight (F=9.318, p=&lt;0.001), BMI (F=9.302, p=&lt;0.001), body fat percentage (F=4.756, p=0.01), body fat mass (F=5.916, p=0.004), and skeletal muscle mass (F=9.380, p=&lt;0.001). Intragroup changes were observed in physical functioning, vitality, and general health in both the exercise and app groups, in addition to role limitations due to physical health in the exercise group.Conclusions. The 12-week exercise program reduced AHI and increased skeletal muscle mass, physical fitness, and HRQoL in four domains. The lifestyle app program reduced weight, BMI, neck circumference, body fat, visceral adiposity and skeletal muscle mass while increased three HRQoL domains in participants with mild-to-moderate SDB.

Tailored culture strategies to promote antimicrobial secondary metabolite production in Diaporthe caliensis: a metabolomic approach

BackgroundIn the search for new antimicrobial secondary metabolites of fungi, optimizing culture conditions remains a critical challenge, as standard laboratory approaches often result in low yields. While non-selective methods, such as modifying culture media, have been effective in expanding the chemical diversity of fungal metabolites, they have not yet established a direct link to key process parameters crucial for further optimization. This study investigates the capacity of Diaporthe caliensis as a biofactory for biologically active secondary metabolites, employing tailored culture media to explore the relationship between chemical diversity and critical process variables.ResultsThe metabolomic profiles, antibacterial activities, and production yields of the extracts were analyzed to progressively adjust the culture conditions. This study was conducted in five steps, evaluating carbon and nitrogen source concentration, nitrogen source type, salt supplementation, and pH adjustment. Altering the rice starch concentration affected biomass yield per unit of oxygen consumed, while modifications to the nitrogen source concentration influenced both the bioactivity and chemical space by Diaporthe caliensis. Despite changes at the metabolome level, the extracts consistently exhibited potent antibacterial activities, influenced by the nitrogen source, added salts and pH adjustments. For instance, when using corn steep liquor and rice starch, supplemented with micronutrients, different metabolites were produced depending on whether buffer or water was used, though both conditions showed similar antibacterial activities (IC50 ≈ 0.10 mg mL− 1 against Staphylococcus aureus and ≈ 0.14 mg mL− 1 against Escherichia coli). In the treatment where buffer was used to stabilize pH change, there was an increase in the production of phomol-like compounds which are associated with known antibiotic properties. In contrast, in the treatments using water, the drop in pH stimulated the production of previously unidentified metabolites with potential antimicrobial activity.ConclusionsThis study proposes a strategic methodology for the tailored formulation of culture media aiming to promote the biosynthesis of diverse secondary metabolites. This approach revealed the critical role of nutrient limitation and pH regulation in stimulating the production of polyketide-lactone derivatives, including the antibiotic phomol. Ultimately, the systematic, custom-designed culture conditions developed in this work offer a promising strategy for expanding the chemical diversity of Diaporthe caliensis, while providing valuable insights into the key parameters needed for optimizing this fungal biofactory.Graphical

Optical Microangiography and Progressive Retinal Nerve Fiber Layer Loss in Primary Angle-closure Glaucoma

Precis Younger patient age (coefficient: 0.10, P=0.04) and greater peak IOP during follow-up (coefficient: -0.14, P=0.03), but not baseline optical microangiography parameters, were significantly associated with a faster rate of RNFL loss in mild-moderate PACG. Purpose: To evaluate the association between optical microangiography (OMAG) measurements and progressive retinal nerve fiber layer (RNFL) loss in primary angle-closure glaucoma (PACG). Methods: In a prospective study, 45 eyes of 30 PACG patients (86 hemifields) with mild to moderate functional damage were longitudinally studied for at least 2 years and with a minimum of 3 optical coherence tomography (OCT) examinations. OMAG imaging was performed at the baseline visit. Effect of clinical parameters (age, gender, presence of systemic diseases, central corneal thickness, mean, peak and fluctuation of intraocular pressure during follow-up), baseline hemifield mean deviation (MD) and baseline OMAG (quadrant peripapillary and macular perfusion density [PD]) on the rate of RNFL change was evaluated using linear mixed models. Results: Average (±SD) hemifield MD, RNFL thickness, peripapillary PD and macular PD of the analyzed quadrants at baseline were -6.0±3.4 dB, 89±21 µm, 40.1±3.5% and 29.6±10.3%, respectively. Rate of quadrant RNFL change was -2.5±1.7 µm/year. Multivariate mixed models showed that younger patient age (coefficient: 0.10, P=0.04) and higher peak IOP during follow-up (coefficient: -0.14, P=0.03) were significantly associated with a faster rate of RNFL loss. Conclusions: Younger patient age and greater peak IOP during follow-up were significantly associated with a faster rate of RNFL loss in PACG patients with mild to moderate severity of functional damage. None of the OMAG parameters at baseline were associated with RNFL thinning suggesting a limited role of OCTA imaging in predicting structural progression in mild-moderate PACG.

Impact of advertising and sales promotion expenses on the sales performance of Jordanian companies: The moderating role of firm size

This study aimed at analyzing the effect of sales promotion and advertising expenses on sales performance, considering firm size as a likely moderating variable.This research conducted regression analyses on 474 Jordanian companies based on the firm’s advertising expenditure, gross margin, firm size, and sales performance. It tested two models: first, direct impact of advertising expenses on sales performance, and, second, firm size affecting the relationship between advertising expenses and sales performance.The findings show that advertising and sales promotion expenses do not have a significant effect on sales performance. Besides, firm size did not moderate this relationship, as referred by a non-significant t-value of –1.459 and a p-value of 0.145. The models explained only 4.1% and 0.5% of the variance in sales performance, respectively, suggesting that other factors play a more significant role.These results suggest that Jordanian firms have to reevaluate their advertising strategies and consider alternative approaches to enhance sales. The research contributes to more understanding of the limited role of advertising in sales performance within the Jordanian market. AcknowledgementThis research was funded through the annual funding track by the Deanship of Scientific Research, from the vice presidency for graduate studies and scientific research, King Faisal University, Saudi Arabia [Grant no. KFU242402].

Health-related Quality of life among patients with Ankylosing Spondylitis and its correlation with disease-related variables. A Cross-Sectional Study in Erbil City

Background and objectives: Ankylosing spondylitis is a chronic, rheumatic, inflammatory disease that basically involves axial skeleton. As a result, functional limitations develop that may negatively affect quality of life. Our aim is to assess the quality-of-life in patients with ankylosing spondylitis and to determine its’ correlation with disease variables including disease activity, functional status, spinal mobility, and bodily pain. Methods: A cross-sectional study enrolled fifty patients with ankylosing spondylitis in the Rizgari teaching hospital was conducted between November 2022 to March 2023. Both short form-36 and ankylosing spondylitis quality of life instruments were used to evaluate Health related quality of life. Bath Disease Activity Index, Bath Functional Index, Bath Metrology Index, and total pain visual analogue scale used to assess disease related variables. Results: fifty patients aged (20-50) years participated, their mean age was (35.4), the majority (80%) were males. The peripheral joints were involved in 42% of these patients. The mean ankylosing spondylitis quality of life score was 8.7 ± (4.6) SD, short form-36 domains of physical role limitation, general health, vitality, and bodily pain had the lowest scores (43.5, 44.6, 45.8, 50.7) respectively. both Bath disease activity index (B = 1.047; p = 0.010) and Bath functional index (B=0.974; p=0.012) were poor predictors of Ankylosing Spondylitis Quality of Life score, while Bath Metrology Index (B = -3.444; p = 0.043) was the main predictor for physical functioning. Conclusion: The health-related Quality of life in participants was significantly impaired. High disease activity, poor functional status and limitation in spinal mobility were recognized as poor predictors of Health-related quality of life.

Future role of ocean thermal energy converters in a 100% renewable energy system on the case of the Maldives

Energy transition on small islands is limited by the scarce availability of land, restricting large-scale implementation of onshore renewable energy technologies such as solar photovoltaics and wind power. Ocean energy technologies provide novel opportunities for land-constrained islands to achieve 100% renewable energy systems. While wave power is increasingly implemented in energy system modelling research, ocean thermal energy converters are not yet a standard technology in renewable energy technology portfolios. This research aims to study the impacts of ocean thermal energy converters on the energy system of the Maldives through a structured sensitivity analysis for the two scenario clusters covering e-fuel import and domestic production. The ocean thermal energy conversion plants are modelled using spatially and temporally resolved resource data and cost assumptions from a global upscaling scenario, considering the technology’s current development stage. Results show that ocean thermal energy converters play a limited role in 'purely' cost-optimised sub-scenarios due to the availability of very low-cost offshore floating photovoltaics, making it difficult for them to compete. Nevertheless, reduced requirement of energy storage technologies due to the stable electricity production of ocean thermal energy converters offers an option to diversify the renewable energy technology portfolio with only a minor increase in cost.

Self-Acceptance in Breast Cancer Patients: A Concept Analysis

Breast cancer is still one of the fears for most women in the world and ranks first regarding the number of cancers in Indonesia and is one of the first contributors to cancer deaths. Breast cancer patients with low self-acceptance will cause stress, lack of confidence, lack of enthusiasm for recovery and will affect poor health management. Self-acceptance is directly proportional to the patient's quality of life. The greater the patient's self-acceptance of their disease, the better the quality of life of breast cancer patients. The purpose of this analysis is to explain self-acceptance in breast cancer patients. An analysis of the concept of self-acceptance was conducted on articles published between 2019 and 2024. The databases used include Google Scholar, Proquest, Pubmed, and Science Direct. The results of the analysis show that the concept of self-acceptance has four attributes, namely, acceptance of physical changes, acceptance of physical and emotional limitations, accepting social and role limitations, accepting the healing process and uncertainty. Based on these attributes, nurses assess self-acceptance in breast cancer sufferers comprehensively. The results of the assessment will be the basis for nurses in determining appropriate diagnoses and nursing interventions to improve self-acceptance in breast cancer patients, by reducing psychological burden to improve quality of life.

Assessment of Platelet Response to Aspirin Therapy and Hemocompatibility-Related Adverse Events in HeartMate 3 Left Ventricular Assist Device Recipients.

Background: Patients with a HeartMate 3 (HM3) left ventricular assist device (LVAD) typically receive anticoagulation and antiplatelet therapy. The HM3 has shown a marked reduction in hemocompatibility-related adverse events (HRAEs) like stroke, bleeding, and pump thrombosis. This study evaluated whether aspirin (ASA) response influences HRAE incidence and if ASA sensitivity changes over time in HM3 recipients. Methods: This single-center, cross-sectional study included 32 HM3 patients (age: 59.0 ± 10.0 years, 15.6% female). ASA sensitivity was assessed twice using the VerifyNow assay, with ASA resistance defined by ASA reactivity units (ARU) > 550. The primary endpoint was HRAE incidence in ASA responders vs. non-responders over two consecutive follow-ups; the secondary endpoint was temporal changes in ASA resistance. Results: At the first follow-up, 13 (40.6%) patients were ASA-resistant, and 8 (28.6%) were resistant at the second follow-up, without significant change (p = 0.22). ASA non-responders and responders had similar ASA doses and baseline characteristics. No significant difference in HRAE incidence was found between ASA non-responders and responders (0.0% vs. 15.8%, p = 0.14), and no additional HRAEs occurred during follow-up. Conclusions: ASA resistance varied considerably among HM3 patients without significant temporal changes, and the demonstrated excellent hemocompatibility supports recent evidence that ASA may have a limited role in the antithrombotic regimen for HM3 recipients.

Valuation survey for SF-6Dv2 in Japan based on the international protocol.

The SF-6D Classification System was recently updated (SF-6Dv2). We performed a valuation survey to construct a value set for the SF-6Dv2 in Japan. An online discrete choice experiment (DCE) with duration was used to estimate a value set for the SF-6Dv2 for Japan based on public preferences. The target sample number was 3800. Respondents were asked to complete 15 choice tasks. A conditional logit model that estimates interactions between time and each dimension was used to develop the value set. The collected sample included 3933 respondents for the DCE tasks. The results of all the unconstrained models showed some inconsistencies. In particular, inconsistencies in the two most severe levels of the role limitation (RL) and vitality (VT) dimensions were observed in all models. The number of inconsistencies was smallest in a core model (n = 3) and in a model for core and common health states (n = 2). The physical functioning (PF) and pain (PA) dimensions had the greatest influence on utility at the overall level across all models. RL, VT, and social functioning (SF) had smaller overall impacts on utility. The PF weights for the two most severe levels are much lower than those in the UK and Australia. The Japanese scores tended to be lower compared with the UK SF-6Dv2 scores. We obtained a value set for Japan (model 5). With the development of this value set, it is now possible to calculate quality-adjusted life years for economic evaluation in Japan when the SF-6Dv2 has been used.

Performance Evaluation of Battery Swapping Stations for EVs: A Multi-Method Simulation Approach

This study presents an optimisation framework for operating a battery swapping station (BSS) to enhance efficiency and sustainability in electric vehicle (EV) infrastructure. A hybrid modelling approach combines agent-based discrete event simulation and linear programming to model the dynamic behaviour of batteries and operational processes within the BSS. The model considers factors such as charging speed, battery degradation, grid power constraints, customer behaviour, and range anxiety. The agent-based model simulates the interaction between vehicles, batteries, and the station, capturing the stochastic nature of EVs’ arrivals and battery demand with the discrete event simulation. The linear programming component optimises battery state transitions to minimise degradation and ensure that the demand is met while respecting the power limits of the grid. Different battery types are considered based on vehicle category, each with specific capacity and usage patterns, reflecting real-world market conditions. The results demonstrate that the proposed optimisation framework can effectively manage the complex operational needs of a BSS. The proposed framework effectively balances service quality with resource efficiency by employing a strategic mix of charging modes and inventory management, reducing operational and degradation costs. This approach supports a more sustainable EV infrastructure, highlighting BSS as a viable solution to enhance the efficiency and sustainability of EV operations. Furthermore, the analysis highlights the critical role of power limits in determining charging strategies and their impact on operational efficiency. The findings suggest that with optimised operations, BSS can play a critical role in accelerating the adoption of EVs by offering a faster, more reliable, and sustainable alternative.

Mixotrophic protists and ecological stoichiometry: connecting homeostasis and nutrient limitation from organisms to communities

In recent decades, there has been a growing recognition that mixotrophy, the ability to utilize both phototrophy and phagotrophy, is more common among plankton than previously assumed. Even though mixotrophs can become highly abundant, especially under nutrient limitation, and significantly alter nutrient cycling and food-web dynamics due to their dual nutritional modes, a comprehensive synthesis from a stoichiometric perspective is still lacking. We conducted a systematic literature review in which we identified over 130 studies that directly relate nutrient ratios to mixotrophic protists at the organism to community scale. By conceptually linking mixotrophy with the concept of ecological stoichiometry, we provide insights into (1) the role of mixotrophic metabolism and nutrient limitation in regulating cellular homeostasis, (2) mixotroph abundance and community scale responses to nutrient limitation, and (3) the specific case of harmful algal bloom forming mixotrophs. On the organism scale, the existing literature points towards a stabilizing effect of mixotrophic metabolism on elemental composition, and the use of grazing as a compensation mechanism under stoichiometric imbalances in the water and prey. At the community scale, mixotrophs were found to increase in abundance relative to strict autotrophs and heterotrophs in nutrient-limited communities, and provide beneficial food for zooplankton grazers by maintaining relatively low and stable stoichiometry. Furthermore, global-scale models and studies of harmful algal blooms reveal the increasing importance of mixotrophs under climate change – highlighting the need for continued research addressing the interactions between mixotrophs and dynamic stoichiometry to understand the impacts of mixotrophs on global nutrient cycles.

Long-term quality of life and surgical outcome of female congenital adrenal hyperplasia patients.

To investigate the long-term quality of life and surgical outcome of female patients with congenital adrenal hyperplasia (CAH). Questionnaires for health-related quality of life (HRQoL) outcome (WHO-5, SF-36), lower urinary tract symptoms (ICIQ-FLUTS) and sexual outcome (ICIQ-FLUTSsex) were administered to adult CAH patients. Paediatric CAH patients and their parents were invited to complete WHO-5, PedsQL-4.0-SF15-Generic Core Scales and ICIQ-CLUTS. Six (46%) adults and 7 (54%) children with 21-hydroxylase-deficiency (age ranged from 8 years to 53 years) were recruited. Eleven (85%) had undergone a feminising genitoplasty. In the adult group, no statistically significant difference was identified in the HRQoL and ICIQ-FLUTS scores. Mean overall score of ICIQ-FLUTSsex was lower but not significantly in adult patients compared to controls (7.3 ± 2.9 vs. 2.9 ± 3.4, P = 0.06). A statistically significant negative correlation (r = -0.98, P = 0.02) was found between age at first operation and role limitations due to emotional problems in SF-36. No statistically significant difference was identified in the self-reported HRQoL and ICIQ-CLUTS scores in the paediatric group compared to controls. However, parent's report showed a statistically significant difference in school functioning (73.8 ± 18.9 vs. 91.2 ± 18.7, P = 0.02) and emotional functioning (80.3 ± 15.9 vs. 94.7 ± 12.7, P = 0.007). Our data did not show an impaired HRQoL nor long-term lower urinary tract symptoms in CAH patients' self-reports. Healthcare team should pay more attention to adult patient's sexual function.

Enablers and Barriers of Sustainability for Small Public Purchases

This study examines the sustainability of small public purchases, a largely overlooked area despite its substantial aggregate volume and legal flexibility compared to large purchases. We aim to understand if the sustainability potential in small public purchases is utilized and how it can be leveraged, providing insights into the dynamics of small purchases and offering practical guidance for policy and organizational change. Through case studies of five Dutch water authorities, incorporating interviews and document analyses, we examine internal and external factors that may inhibit or promote sustainability in small purchases. The findings indicate that sustainability currently plays a limited role in small purchases. Contrary to previous research, external factors do not drive sustainability in small purchases, as the focus remains on large purchases. All internal factors studied are perceived as barriers to achieving sustainable small purchases. We discuss that the external factor of “legal requirements” holds the most untapped potential to become a driver for sustainable small purchases. Additionally, we highlight “accountability” as an important internal factor, suggesting that improved accountability could lead to greater resources, higher risk tolerance, and increased organizational attention. Finally, we suggest that promoting sustainability in small purchases requires addressing underlying challenges, including its limited visibility.

Sex hormones and reproductive factors with cardiac arrhythmia and ECG indices: a mendelian randomization study

BackgroundSex is a determinant of the incidence and etiology of arrhythmia. Observational and basic studies suggest that sex hormones are essential in this process; however, the relationship between sex hormones and arrhythmia remains unclear. Mendelian randomization (MR) was used to investigate the causal relationships between sex hormone levels, arrhythmia, and electrocardiographic (ECG) indices.MethodsLarge genome-wide association studies (GWAS) data on sex hormones, stratified by sex, from the UK biobank consortium, were used as exposure data, and data on atrial fibrillation (AF), atrioventricular block, sick sinus syndrome, paroxysmal tachycardia, and ECG indices were obtained from the FinnGen consortium and summarized large GWAS data. Inverse variance weighting or wald odds was used as the primary analytical method, and weighted medians and MR-Egger regression were used for complementary analyses. The results of the MR of sex hormones and AF from different sources were analyzed using a meta-analysis. Summary-data-based MR analysis was utilized to explore the relationship between sex-hormone related drugs and arrhythmia.ResultsIn men, genetically predicted higher estradiol concentrations were associated with a lower risk of AF (odds ratio: 0.908 [0.852–0.967]; p = 0.0029], whereas genetically predicted higher concentrations of total testosterone were associated with lower heart rate variability. Sex hormones showed no association with atrioventricular block, sick sinus syndrome, paroxysmal tachycardia, resting heart rate, P wave duration, P wave terminal force in lead V1 [PTFV1], PR interval, QRS duration, QTc [QT interval corrected by heart rate], ST duration, spatial [spQRSTa] and frontal [fQRSTa] QRS-T angles in males. In females, there was no significant evidence that sex hormones are associated with arrhythmias or ECG indices.ConclusionIn this study, we identified a potential causal relationship between estradiol and the risk of AF in males. However, there was no significant association between sex hormones and either arrhythmias or ECG indices in females. These results suggested that sex hormones may play a limited role in cardiac arrhythmias, which requires further verification.

Number of electrons in a homogeneous field using delta function normalization

Abstract The number of electrons in a homogeneous electric field is derived quantum mechanically for a certain range. Using the delta function normalization method, which is described in detail in Landau–Lifshitz’s Quantum Mechanics, the normalization coefficient of the wavefunctions with continuous energy eigenvalue spectra is obtained. Subsequently, the number of electrons in a one-dimensional homogeneous field in a certain region is derived from this normalization coefficient. We illustrate the derivation of physical quantities using normalization coefficients through selected examples. The derivation provides an interesting application of delta function normalization, and thus can serve as a good textbook example of this normalization method, which used to play a limited role in quantum mechanics.

Ultrasound for Postoperative and Iatrogenic Peripheral Nerve Lesions: What Do Radiologists Need to Know?

Iatrogenic nerve injuries are common and require an immediate accurate diagnosis to allow surgical treatment within a short window of opportunity. Targeted investigation using high-resolution ultrasound (US) allows an accurate diagnosis in the acute phase when electrophysiology has a limited role. By identifying the exact site of injury, mechanism, and type of nerve damage, US can help determine the prognosis of the lesion and the need for surgical management. This pictorial review discusses the role of high-resolution US in the work-up of iatrogenic nerve injuries, with an emphasis on US appearances and the clinical knowledge needed by the radiologist to provide solutions to clinical challenges.

Multimodal management of PD‐L1 positive sinonasal inverted papilloma with malignant transformation

AbstractInverted papillomas (IP) are rare sinonasal tumors (Schneiderian papillomas) characterized by local invasion, with high recurrence rates and potential for malignant transformation into squamous cell carcinoma (SCC ex‐IP). Traditionally, the mainstay of treatment has been surgical resection, often challenging due to invasion of the skull base or vital neurovascular structures. In advanced cases, prognosis is poorer and radiation therapy is the current standard of care with limited role of systemic therapy. We present a case of unresectable SCC ex‐IP treated with sequential chemoradiation and PD‐1 immunotherapy (pembrolizumab) and achieving complete response at 1 year. This case suggests that immunotherapy can effectively treat SCC ex‐IP and we propose that programmed death ligand‐1 (PD‐L1) testing should be performed in all advanced cases. Prospective studies are needed to validate immunotherapy in adjuvant or frontline treatments for advanced SCC ex‐IP, and the role of PD‐L1 as a predictive biomarker.

CT-defined muscle density as a prognostic factor in multiple myeloma undergoing autologous stem cell therapy: a retrospective single center study.

Skeletal muscle quality assessment can be performed by cross-sectional imaging. Skeletal muscle density (SMD) identified to be of prognostic relevance of several clinically outcomes in patients with hematological diseases. The purpose of the present study was to establish the effect of SMD on overall survival (OS) and progression-free survival (PFS) in patients with multiple myeloma (MM). All patients with MM were retrospectively analyzed between 2009 and 2019. 127 patients were included into the analysis. Whole-body computed tomography (CT) was used to calculate skeletal muscle index (SMI), SMD, albumin-gauge score and intramuscular adipose tissue content (IMAC). Overall, 28 patients (22.0%) of the patient sample died. In the discrimination analysis muscle density was higher in non-survivors compared to survivors (mean 30.8 ± 12.5 versus 24.1 ± 15.8, p = 0.03) and IMAC was lower in non-survivors (-0.66 ± 1.8 versus -0.25 ± 0.21, p = 0.01). These differences, however, were not demonstrated in the logistic regression analysis, which could not show prognostic relevance for the investigated muscle density parameters on PFS or OS. CT-defined muscle density parameters have no prognostic relevance on survival in patients with MM undergoing autologous stem cell therapy, which was demonstrated in a comprehensive analysis. These results corroborate previous smaller studies that body composition might have a limited role in this tumor entity.