bluuebunny/crossref_metadata_2025 huggingface dataset:
Microscale damper prototype: A preliminary study on suppressing air flow oscillations within microchannels
Authors: Fichera A , Pagano A , Volpe R
Published: February 2024

This research introduces a novel micro-damper designed to mitigate pressure and velocity oscillations from a piezoelectric micropump in microfluidic environments. Unlike existing research focusing on damping in incompressible liquid flows with methods like elastic films and PDMS membranes, this study proposes a novel micro-damper prototype. Integrated into a microdevice for particle granulometric separation and detection, the damper connects to a piezoelectric micropump outlet and to a focusing microchannel inlet, followed by a capacitive sensor for size-based particle counting. Preliminary analysis determined an optimal airflow velocity at w = 0.5 m/s for accurate focusing and counting under laminar conditions. The micro-damper, constrained by the piezoelectric pump’s geometry, features a 27 µm high and 1000 µm wide cross section. Its outlet supports two potential focusing microchannel inlet configurations of 30 µm or 40 µm. Distinctively, it incorporates two symmetrical backward micro-channels connecting to the atmosphere, allowing direct piezometric contact between the main flow and an infinite compliant volume. OpenFOAM simulations confirm the damper’s effectiveness in maintaining laminar outlet flow and suppressing micropump disturbances. Thus, the proposed micro-damper ensures optimal inlet conditions for subsequent microchannel processes, enabling stable particle separation and detection in controlled airflow samples.
Thermal-hydraulic study of the EU-DEMO Helium Cooled Pebble Bed Breeding Blanket Primary Heat Transport System
Authors: Vallone E , Agnello G , Bongiovì G , Castrovinci F M , D’Amico S , Di Maio P A , Moscato I , Quartararo A
Published: February 2024

The European DEMO reactor will work under normal operating conditions in accordance with a pulsed duty cycle. However unplanned and planned transients of plasma overpower may occur compromising the integrity of its plasma-facing components structures. Consequently, adopting appropriate tools is essential to accurately and consistently model the thermal-hydraulic response of the involved cooling systems under both normal operating conditions and accidental events. Given this background, the University of Palermo, in collaboration with EUROfusion, started a research work to study the thermal-hydraulic behaviour of the Primary Heat Transport System (PHTS) of the Helium Cooled Pebble Bed Breeding Blanket (HCPB BB) of the DEMO device under steady-state and transient conditions. The activity has been performed adopting a computational approach, employing the thermal-hydraulic system code TRACE version 5.0 patch 6. The key point of the work has been the code-to-code benchmark with the outcomes previously obtained with the RELAP5-3D code, to estimate the impact of the physical models, numerical resolution schemes and modelling techniques adopted on the predictive capabilities of the system codes considered. The models and the analysis results are presented and critically discussed herein.
Thermal performance of clay bricks with different fillings: a CFD analysis
Authors: Merli F , Susta S , Buratti C
Published: February 2024

The thermal conductivity of 15 loadbearing and infill bricks was calculated through a Computational Fluid Dynamic (CFD) analysis. Clay bricks filled with air, expanded polystyrene EPS, and graphitized expanded polystyrene were selected from the catalogue of the manufacturer F.B.M. - Fornaci Briziarelli Marsciano. The company provided the geometric features of each block and the thermal characteristics of the clay mix and the filling. The thermal conductivity value of each air cavity was calculated in compliance with UNI EN ISO 6946. Each volume was discretized in triangular meshes. The equivalent thermal conductivity of each block was calculated starting from the simulation of the isotherms trend inside the sample and from the heat flux passing through it. The obtained results were discussed depending on the filling, the geometry, and the hole percentage. In general, thermal conductivity increases with hole percentage in the bricks with air. Similar geometries have similar thermal behaviour. EPS or graphitized EPS involve better thermal performance as the hole percentage increases. Finally, the influence of the different orientations of the blocks was investigated. Equivalent thermal conductivity values increase for horizontally-brick placed, especially in homogeneous and compact geometries.
Critical assessment of thermal conductivity models for Miscibility Gap Alloy-based composite Phase Change Materials for high temperature Thermal Energy Storage
Authors: Molteni M. , Carraretto I. M. , Bassani P. , Gariboldi E. , Lucchini A. , Colombo L. P. M.
Published: February 2024

Miscibility Gap Alloys (MGAs), such as Al-Sn-based systems, provide a viable solution for the development of composite Phase Change Materials (PCMs) for Thermal Energy Storage (TES) purposes. Their successful production depends on the cooling rate imposed to the melt. Finite Element Analyses (FEA), which relies also on thermal conductivity values, represent a powerful tool for the design of the production process. Thermal conductivity, which depends on the arrangement of the phases in the system, also affects the thermal response of the alloy. In the view of evaluating the impact of the phase morphology, the authors adapted some of the models developed for composites and solutions to Al-Sn and Al-Sn-Si-Mg alloys, characterized by broad solidification ranges in terms of composition and temperature and by significantly different phases thermal conductivity. In the fully-liquid range, Filippov and Novoselova model was selected for the description of both alloys. Models that consider sphere-like dispersions give values quite close to the theoretical upper Wiener bound when the high-melting phase is solid. The phase morphology impact is relevant when the solidification range is considered. The resulting arrangement-related thermal conductivity curves are compared to those supplied by CALPHAD-based software and to available literature data.
Evaluating the potential of persistent luminescence in counteracting urban overheating
Authors: Chiatti C , Fabiani C , Bou-Zeid E , Pisello AL
Published: February 2024

In recent years, the use of numerical simulations to model real atmospheric conditions over cities has become increasingly popular. One of the primary objectives of these models is to assess the efficacy of various strategies for mitigating the Urban Heat Island (UHI) phenomenon. At the same time, researchers have developed and studied new adaptive materials for building applications that aim to reduce buildings’ energy consumption and improve urban microclimate conditions, while performing radiative cooling. Among the new generation of passive cooling solutions, persistent luminescent (PL) materials have emerged as a cutting-edge option for energy-saving purposes, owing to their ability to reject the incident solar radiation through both reflection and light emission. Here, the Princeton Urban Canopy Model (PUCM) is used to evaluate the potential of an advanced PL roof coating to counteract urban overheating. The phenomenon of persistent luminescence is modeled for the first time, taking advantage of experimentally obtained parameters coming from previous studies. Results demonstrate how persistent luminescence can effectively mitigate surface overheating reducing the roof’s surface temperature and net shortwave radiation up to 1.15 °C and 35 W/m2 respectively, with consequent benefits to the overall energy balance of the envelope. Such results may be further increased with the optimization of PL materials for engineering solutions.
Experimental analysis of insulating materials using Guarded Hot Box - Preliminary results
Authors: de Rubeis T , Ciccozzi A , Paoletti D , Ambrosini D
Published: February 2024

The containment of energy consumption in the construction sector strongly depends on the envelope, which is mainly responsible for heat loss in buildings. Thus, great attention should be paid to the selection of thermally-performing materials. In this work, preliminary results of three different configurations of walls in real size have been compared, conducting the analyses with the heat flow meter method inside the Guarded Hot Box apparatus, capable of guaranteeing repeatable and controlled conditions. The analyses were carried out with two types of heat flow meters, characterized by different sensitivity. The side of the wall facing the hot chamber has been insulated with rock wool for all the experiments, while the other side has been insulated first with expanded polystyrene (EPS) with graphite, then with hemp, and finally with cork. The results showed that the sample with the best thermal behaviour is the first one, i.e., the wall with EPS with graphite, characterized by a transmittance value between 0.148 W/m2K and 0.153 W/m2K. The other two configurations, characterized by the use of natural materials, showed worse performance with conductance values about 20% higher than EPS. The percentage differences between the two heat flux sensors for the experimental campaigns ranged from 2.8% to 4.4%.
Improving the energy performance of a 3D-printed wall using recycled material
Authors: Neri M , Licciardello L , Reggia A , Pilotelli M , Lezzi A M
Published: February 2024

In this paper, we present the results of a preliminary experimental campaign conducted on a 3D-printed wall 40 cm thick made of three concrete walls, connected by metal pins and concrete curbs to form three types of cavity - one rectangular and two triangular. The tests were performed in a climatic chamber at the Pietro Pisa Laboratory of the University of Brescia. The wall thermal performance has been evaluated by examining four scenarios in which the cavities have been filled with insulating material made of cellulose-based recycled flakes characterized by a declared thermal conductivity of 0.038 W/mK. The wall thermal transmittance U is measured based on the temperatures and heat fluxes measured through the structure. Based on the degree of filling, the wall thermal transmittance ranges between 1.58 W/m2K for the wall without insulation, and 0.28 W/m2K for the configuration with all cavities completely filled.
Experimental study on a Dual-Source Heat Pump in ground mode to assess the soil thermal response by means of a Distributed Temperature Sensing system
Authors: Natale C , Dongellini M , Naldi C , Morini G L
Published: February 2024

In this paper, a Dual-Source Heat Pump (DSHP), able to exploit both aerothermal and geothermal energy sources, has been tested in ground mode to evaluate experimentally the soil thermal response in presence of an undersized Borehole Heat Exchanger (BHE) field. The field is instrumented with a Distributed Temperature Sensing (DTS) system, by which the geothermal fluid temperature can be measured over the entire length of the boreholes during the heat pump operation. The DSHP has been tested to reproduce the working profile of a heat generator coupled to a reference building, which has been numerically simulated by means of ALMABuild, a Matlab-Simulink tool. Three operating profiles have been identified within the simulation results to define three typical days of the heating season, characterized by different required loads. The results show that a DSHP operated in ground-mode and coupled to a borefield 50% undersized can meet completely the heating needs of a typical winter day, whilst higher building loads must be satisfied exploiting both air and ground sources. In this case, 80% of the undisturbed temperature of the soil can be recovered in an hour when aerothermal energy is extracted, thus the unit efficiency remains high and the investment cost is strongly reduced.
Development and validation of a model for an air-to-air air conditioner
Authors: Ferretto W , Molinaroli L , Inzoli F , De Antonellis S
Published: February 2024

Air conditioning units are responsible for a significant amount of global warming, with demand predicted to triple by 2050. Mathematical models aid in designing energy efficient air conditioners that can contribute to climate change mitigation. This study presents a steady-state model for a air-to-air air conditioner. The proposed model can assist in reducing the number of experiments and optimizing the efficiency of air conditioning systems. It utilizes a bottom-up approach to solve for compressor, condenser, capillary tube, and evaporator sub-models. The compressor is modelled using polynomial equations to determine refrigerant mass flow rate and power consumption based on operating temperatures. Heat exchanger models are solved using finite volume approach and reliable correlations are used for void fraction, friction factor, and heat transfer coefficient calculations. The closing equations are the mass conservation, i.e. constant refrigerant charge, and the equivalence between the mass flow rate sucked by the compressor and the one that flows through the capillary tube, while the evaporating and condensing pressures are the independent variables. The capillary tube is modelled using semiempirical correlations. The model is validated against experimental data at various operating conditions and shows a ±7% agreement for predicted cooling capacity.
Local heat-transfer coefficient estimation in cross-helix corrugated tubes under turbulent regime
Authors: Azam Muhammad Waheed , Malavasi M , Cattani L , Bozzoli F , Rainieri S
Published: February 2024

In a wide variety of engineering applications, convection heat transfer enhancement plays a major role in reducing the heat exchanger’s size and costs and increasing their efficiency. The passive methods for increasing convective heat transfer are the most interesting since they don’t require any external power to achieve the desired enhancement. For this reason, this approach is preferred in the industrial sector of heat exchangers. For the enhancement of the performances of these apparatuses, in particular, the tubular ones used in the pharmaceutical, food, and chemical, the most adopted passive solution is the corrugation of their tube walls. Two pipes characterized by cross-helix corrugation have been experimentally analyzed both investigating the global heat transfer performance and studying the local heat transfer coefficient distribution to profoundly examine the thermal performance enhancement mechanisms of this passive technique. It has been observed that at Re = 16,000, the heat transfer rate in the smaller pitch tube is 18.18% higher than that in the larger pitch tube. The inverse heat conduction problem in the tube wall is addressed to achieve the local coefficient distribution method by using temperature readings collected from an infrared camera on the outer surface of the tube as the initial data.
The role of SRF in achieving the EU landfill targets in the Umbria Region, Italy
Authors: Pazzaglia Aron , Castellani Beatrice
Published: February 2024

In December 2015, the European Commission published the circular economy package “Closing the loop - An European action plan for the Circular Economy” with four quantitative objectives: long-term recycling targets for municipal waste (55% in 2025, 60% in 2030 and 65% in 2035) and landfill target of 10% by 2030. In Umbria (Italy) 43% of waste are landfilled in 2020, so the region is far from the European target. Hence, it is significant to analyse different strategies to improve the waste management in the region. In particular, the main issue is how to reduce waste landfill in the most efficient way. The SRF and waste-to-energy approaches are the most interesting to study as a substitute for landfilling. In the communication “The role of waste-to-energy in the circular economy”, the European Commission clarifies the position covered by the different energy processes in the waste hierarchy and identifying the technologies with the highest potential in terms of efficient management of resources and environmental impact. Among the most efficient waste-to-energy technologies, the document mentions the gasification of recovered solid fuel (SRF) and co-incineration of the resulting synthesis gases in the combustion plant to replace fossil fuels in the production of electricity and heat and co-incineration in the cement production. The European Commission recognizes the important role of energy recovery in the transition to the circular economy, if this does not stop the improvement in recycling rates. In this paper, MSW management policy in Umbria (Italy) and possible solutions are discussed. The paper considers three scenarios in the management of MSW: i) direct combustion of residual waste in waste-to-energy plants; ii) combustion of SRF in waste-to-energy plants; iii) combustion of F-SRF in dedicated plants (cement plant). All three scenarios may be able to match the 10% landfill EU target.
Control of CO2 evaporation in an integrated photovoltaic module: experiments and modelling
Authors: Azzolin M , Zanetti E , Conte R , Del Col D
Published: February 2024

The use of environmentally friendly refrigerants and the improvement of the system performance are two main topics in the research on heat pump technology. Given the recent limitations imposed on the usage of high global warming potential refrigerants, there is a growing demand in the market for the adoption of natural refrigerants, like CO2. Nevertheless, CO2 heat pumps operate under transcritical conditions, which can adversely affect its efficiency. Therefore, incorporating a solar heat source into a CO2 heat pump can offer a solution to mitigate low system performance issues. In the present study, a photovoltaic module integrated with the evaporator of a CO2 heat pump is experimentally studied. The PV-T evaporator exploits solar radiation to both generate electricity in the PV cells and ensure the evaporation of CO2 in the collector’s tubes. Simultaneously, the PV conversion efficiency is improved by the cooling effect of the evaporation. The present evaporator works in dry expansion mode, thus the refrigerant flow after the expansion device is sent to the solar collectors, where it evaporates before returning to the compressor. When using a PV-T evaporator, it is necessary to prevent superheating in the evaporator to keep a uniform and efficient cooling of the PV cells. The current heat pump design prevents the occurrence of superheated vapor at the PV-T evaporator’s outlet. Beside the experimental activity a dynamic numerical model of the system has been developed and validated.
Design and thermal test of high-vacuum insulator for heat delivery pipes
Authors: Capolupo F. , D’Alessandro C. , Strazzullo P. , Russo R. , Musto M.
Published: February 2024

Thermal piping insulation of implants is crucial for heat delivery, production, collection, or storage at high temperature values. It is currently obtained by enveloping low thermal conductivity materials such as rockwool, fiberglass, polyurethane, polystyrene, and aerogel. However, better performances can be reached by adopting vacuum technology. In this case, conductive losses are annihilated, and the radiative heat transfer mechanism represents the only loss mechanism. Here, we compare a high vacuum-based novel solution and the traditional insulation for heat delivery applications. We propose a high vacuum- based solution consisting of an evacuated gap that surrounds the hot pipe coated by a thin aluminium foil. Experimental results using this novel solution show a fivefold reduction of the thermal radiation losses compared to the traditional solutions when in the temperature range between 100 °C and 250 °C.
Fluid dynamic parameters of naturally derived hydroxyapatite scaffolds for in vitro studies of bone cells
Authors: Salerno E , d’Adamo A , Corda G , Ongaro C , Zardin B , Orlandi G , Ruffini A , Bertacchini J , Angeli D
Published: February 2024

Hydroxyapatite scaffolds obtained from the biomorphic transformation of wood are characterized from a fluid dynamic point of view. Such material of recent introduction offers great advantages for the in vitro study of bone cells, mostly in virtue of its peculiar porous structure. Determining the flow resistance and morphological parameters of these scaffolds is an essential step towards their practical use in bioreactors and microfluidic devices. To this aim, a series of tests involving a draining fluid are performed on a set of disc-shaped scaffolds, followed by the microscopy analysis of the pores visible on the sample faces. Contrarily to what expected, a temperature dependence is observed for the flow resistance, even after normalizing it by the fluid properties. The interpretation of the experimental results is assisted by numerical outcomes from Computational Fluid Dynamics modelling, which underline some limitations in the application of classical laws to the present problem. While the complex and variable internal structure of the scaffolds prevents the systematic use of simplified formulae, a correlation is found between the flow resistance and the pore geometry, which can facilitate the characterization of further samples.
Generative machine learning for detector response modeling with a conditional normalizing flow
Authors: Xu Allison , Han Shuo , Ju Xiangyang , Wang Haichen
Published: February 2024

In this paper, we explore the potential of generative
machine learning models as an alternative to the computationally
expensive Monte Carlo (MC) simulations commonly used by the Large
Hadron Collider (LHC) experiments. Our objective is to develop a
generative model capable of efficiently simulating detector
responses for specific particle observables, focusing on the
correlations between detector responses of different particles in
the same event and accommodating asymmetric detector responses. We
present a conditional normalizing flow model (𝒞𝒩ℱ) based
on a chain of Masked Autoregressive Flows, which effectively
incorporates conditional variables and models high-dimensional
density distributions. We assess the performance of the
𝒞𝒩ℱ model using a simulated sample of Higgs boson
decaying to diphoton events at the LHC. We create
reconstruction-level observables using a smearing technique. We show
that conditional normalizing flows can accurately model complex
detector responses and their correlation. This method can
potentially reduce the computational burden associated with
generating large numbers of simulated events while ensuring that the
generated events meet the requirements for data analyses. We make
our code available at https://github.com/allixu/normalizing_flow_for_detector_response.
Pharmacist perceptions of delivering patient care through telehealth
Authors: Lobkovich Alison , Javed Sameera , Hammoud Reem , Habhab Ayah , Lipari Melissa
Published: February 2024

Purpose

To evaluate pharmacists’ perceptions of the benefits of and barriers to telehealth as experienced in actual telehealth visits with patients.

Methods

This qualitative study used virtual focus groups and a validated questionnaire (the Health Optimum Telemedicine Acceptance [HOTA] survey) to assess telehealth facilitators and barriers. Participants were included if they were licensed pharmacists utilizing telehealth in the outpatient setting. Pharmacist focus group responses were transcribed and analyzed using Miles and Huberman’s qualitative data analysis model.

Results

Six pharmacists participated in this study. Their responses were placed into 2 categories: clinical effectiveness and patient experience. All participants had performed at least 20 virtual visits, and all agreed that telehealth improved patients’ health status. Respondents agreed that telehealth results in more frequent patient interactions and allows for provision of multiple types of care virtually. However, technological difficulties and the inability to provide physical examinations and obtain laboratory values were identified limitations. The surveyed pharmacists agreed that the main benefit that patients gained from telehealth was the elimination of transportation concerns, allowing increased access to care. However, pharmacists voiced their concern for patient privacy and barriers to educating patients on proper use of medical devices.

Conclusion

Pharmacists felt that telehealth was useful in several clinical scenarios. However, they also identified opportunities to improve its development in clinical practice. Further investigation must be done to better grasp impediments to telehealth in order to provide the most effective patient care.
labelSeg: segment annotation for tumor copy number alteration profiles
Authors: Zhao Hangjia , Baudis Michael
Published: February 2024

Somatic copy number alterations (SCNAs) are a predominant type of oncogenomic alterations that affect a large proportion of the genome in the majority of cancer samples. Current technologies allow high-throughput measurement of such copy number aberrations, generating results consisting of frequently large sets of SCNA segments. However, the automated annotation and integration of such data are particularly challenging because the measured signals reflect biased, relative copy number ratios. In this study, we introduce labelSeg, an algorithm designed for rapid and accurate annotation of CNA segments, with the aim of enhancing the interpretation of tumor SCNA profiles. Leveraging density-based clustering and exploiting the length–amplitude relationships of SCNA, our algorithm proficiently identifies distinct relative copy number states from individual segment profiles. Its compatibility with most CNA measurement platforms makes it suitable for large-scale integrative data analysis. We confirmed its performance on both simulated and sample-derived data from The Cancer Genome Atlas reference dataset, and we demonstrated its utility in integrating heterogeneous segment profiles from different data sources and measurement platforms. Our comparative and integrative analysis revealed common SCNA patterns in cancer and protein-coding genes with a strong correlation between SCNA and messenger RNA expression, promoting the investigation into the role of SCNA in cancer development.
Cognitive function mediates the relationship between age and anaesthesia-induced oscillatory-specific alpha power
Authors: Boncompte Gonzalo , Freedman Isaac , Qu Jason , Turco Isabella , Khawaja Zain Q , Cortinez Ignacio , Pedemonte Juan C , Akeju Oluwaseun
Published: February 2024

Cognitive decline is common among older individuals, and although the underlying brain mechanisms are not entirely understood, researchers have suggested using EEG frontal alpha activity during general anaesthesia as a potential biomarker for cognitive decline. This is because frontal alpha activity associated with GABAergic general anaesthetics has been linked to cognitive function. However, oscillatory-specific alpha power has also been linked with chronological age. We hypothesize that cognitive function mediates the association between chronological age and (oscillatory-specific) alpha power. We analysed data from 380 participants (aged over 60) with baseline screening assessments and intraoperative EEG. We utilized the telephonic Montreal Cognitive Assessment to assess cognitive function. We computed total band power, oscillatory-specific alpha power, and aperiodics to measure anaesthesia-induced alpha activity. To test our mediation hypotheses, we employed structural equation modelling. Pairwise correlations between age, cognitive function and alpha activity were significant. Cognitive function mediated the association between age and classical alpha power [age → cognitive function → classical alpha; β = −0.0168 (95% confidence interval: −0.0313 to −0.00521); P = 0.0016] as well as the association between age and oscillatory-specific alpha power [age → cognitive function → oscillatory-specific alpha power; β = −0.00711 (95% confidence interval: −0.0154 to −0.000842); P = 0.028]. However, cognitive function did not mediate the association between age and aperiodic activity (1/f slope, P = 0.43; offset, P = 0.0996). This study is expected to provide valuable insights for anaesthesiologists, enabling them to make informed inferences about a patient’s age and cognitive function from an analysis of anaesthetic-induced EEG signals in the operating room. To ensure generalizability, further studies across different populations are needed.
In Search of Status: China and the USA in United Nations Speeches, 1970–2020
Authors: Parent Joseph M , MacDonald Paul K
Published: February 2024

What is China’s status? The answer has major repercussions for China’s rights, responsibilities, and risk acceptance in international disputes. Although definitions of status are contested, there is broad agreement that it is socially constructed and relative to peer states, which makes measuring it difficult. We aim to address definitional and measurement problems by using text as data from United Nations General Debates speeches, 1970–2020. This allows one to see the language China uses to refer to itself, the language by which others refer to China, and how that compares to the USA. Contrary to conventional wisdom, we find that China is not more status obsessed than its peer, is not more status obsessed over time, and is not gaining in status over time. The implications for world politics are complex but suggest that status will not be a primary cause of conflict in the foreseeable future.
Biomarkers vs Machines: The Race to Predict Acute Kidney Injury
Authors: Ghazi Lama , Farhat Kassem , Hoenig Melanie P , Durant Thomas J S , El-Khoury Joe M
Published: February 2024

Background

Acute kidney injury (AKI) is a serious complication affecting up to 15% of hospitalized patients. Early diagnosis is critical to prevent irreversible kidney damage that could otherwise lead to significant morbidity and mortality. However, AKI is a clinically silent syndrome, and current detection primarily relies on measuring a rise in serum creatinine, an imperfect marker that can be slow to react to developing AKI. Over the past decade, new innovations have emerged in the form of biomarkers and artificial intelligence tools to aid in the early diagnosis and prediction of imminent AKI.

Content

This review summarizes and critically evaluates the latest developments in AKI detection and prediction by emerging biomarkers and artificial intelligence. Main guidelines and studies discussed herein include those evaluating clinical utilitiy of alternate filtration markers such as cystatin C and structural injury markers such as neutrophil gelatinase-associated lipocalin and tissue inhibitor of metalloprotease 2 with insulin-like growth factor binding protein 7 and machine learning algorithms for the detection and prediction of AKI in adult and pediatric populations. Recommendations for clinical practices considering the adoption of these new tools are also provided.

The race to detect AKI is heating up. Regulatory approval of select biomarkers for clinical use and the emergence of machine learning algorithms that can predict imminent AKI with high accuracy are all promising developments. But the race is far from being won. Future research focusing on clinical outcome studies that demonstrate the utility and validity of implementing these new tools into clinical practice is needed.
A Retrospective Study of Factors Contributing to the Performance of an Interferon-Gamma Release Assay Blood Test for Tuberculosis Infection
Authors: Song Junhyup , Kim Sinyoung , Park Younhee
Published: February 2024

Background

Tuberculosis (TB) remains a significant global health concern. Accurate detection of latent TB infection is crucial for effective control and prevention. We aimed to assess the performance of an interferon-gamma release assay blood test (QuantiFERON-TB Gold Plus [QFT-Plus]) in various clinical contexts and identify conditions that affect its results.

Methods

We conducted a retrospective analysis of 31 000 QFT-Plus samples collected from 26 000 subjects at a tertiary hospital in South Korea over a 4-year period and compared the rates of positivity and indeterminate results across diverse clinical situations. We also analysed the contribution of the QuantiFERON TB2 tube to the test’s sensitivity and determined optimal cutoff values for 3 hematologic parameters to distinguish false-negative results. These cutoff values were validated in a separate cohort of subjects with microbiologically confirmed subclinical TB.

Results

Rates of QFT-Plus positivity and indeterminate results were disparate across diagnoses. The TB2 tube increased QFT-Plus sensitivity by 4.1% (95% CI, 1.1%–7.0%) in patients with subclinical TB. Absolute lymphocyte count ≤1.19 × 109/L, absolute neutrophil count ≥5.88 × 109/L, and neutrophil-to-lymphocyte ratio ≥4.33 were effective criteria to discriminate false-negative QFT-Plus results. Application of the hematologic criteria, individually or combined with mitogen response <10 IU/mL, substantially improved performance in the main study cohort and the validation cohort.

Conclusions

These findings highlight the influence of clinical context and patient hematologic profiles on QFT-Plus results. To minimise neglected latent TB infections due to false-negative QFT-Plus results, serial retesting is advisable in patients with severe lymphopenia or neutrophilia, particularly when the mitogen response is <10 IU/mL.
Complex percutaneous transcatheter closure of incomplete surgical ligation of the left atrial appendage: a case report
Authors: Tomaselli Michele , Verolino Giuseppe , Sganzerla Paolo , Gavazzoni Mara
Published: February 2024

Background

Incomplete surgical left atrial appendage (LAA) closure, in the form of incompletely surgically ligated LAA (ISLL), increases thrombo-embolic risk in patients with atrial fibrillation (AF). Although its management is not standardized, the percutaneous closure of ISLL could be an alternative in patients with contraindication for anticoagulants. We present the case of a percutaneous transcatheter LAA device implantation in a patient with AF and ISLL, complicated by severe anaemia.

Case summary

A 83-year-old woman, with permanent AF and a history of previous surgical LAA ligation, was referred to our hospital for fatigue and worsening dyspnoea. Laboratory tests showed severe microcytic anaemia, with a haemoglobin level of 4.9 g/dL (normal reference: 13.8–18.0 g/dL). Oesophagogastroduodenoscopy and colonoscopy excluded signs of either recent or ongoing haemorrhage. After achieving clinical improvement by haemotransfusions, we performed a transoesophageal echocardiography that showed an ISLL with a narrow neck of 5 mm. Since the patient had high thrombo-embolic and haemorrhagic risk (CHA2DS2-VASc risk score of 4 and a HAS-BLED score of 4), we decided to discontinue anticoagulant therapy and perform elective percutaneous transcatheter LAA occlusion (LAAO) with an Amplatzer Amulet device. Patient was discharged in good clinical status. After three months, the stability of haemoglobin level and the absence of device thrombosis allowed the discontinuation of antithrombotic therapy.

Discussion

We described the first experience of percutaneous ISLL closure with Amulet device (Abbott Vascular, Santa Clara, CA, USA), a commercially available device for LAAO. The procedure was feasible and safe, without long-term complications.
Predicting heart failure outcomes by integrating breath-by-breath measurements from cardiopulmonary exercise testing and clinical data through a deep learning survival neural network
Authors: Ross Heather J , Peikari Mohammad , Vishram-Nielsen Julie K K , Fan Chun-Po S , Hearn Jason , Walker Mike , Crowdy Edgar , Alba Ana Carolina , Manlhiot Cedric
Published: February 2024

Aims

Mathematical models previously developed to predict outcomes in patients with heart failure (HF) generally have limited performance and have yet to integrate complex data derived from cardiopulmonary exercise testing (CPET), including breath-by-breath data. We aimed to develop and validate a time-to-event prediction model using a deep learning framework using the DeepSurv algorithm to predict outcomes of HF.

Methods and results

Inception cohort of 2490 adult patients with high-risk cardiac conditions or HF underwent CPET with breath-by-breath measurements. Potential predictive features included known clinical indicators, standard summary statistics from CPETs, and mathematical features extracted from the breath-by-breath time series of 13 measurements. The primary outcome was a composite of death, heart transplant, or mechanical circulatory support treated as a time-to-event outcomes. Predictive features ranked as most important included many of the features engineered from the breath-by-breath data in addition to traditional clinical risk factors. The prediction model showed excellent performance in predicting the composite outcome with an area under the curve of 0.93 in the training and 0.87 in the validation data sets. Both the predicted vs. actual freedom from the composite outcome and the calibration of the prediction model were excellent. Model performance remained stable in multiple subgroups of patients.

Conclusion

Using a combined deep learning and survival algorithm, integrating breath-by-breath data from CPETs resulted in improved predictive accuracy for long-term (up to 10 years) outcomes in HF. DeepSurv opens the door for future prediction models that are both highly performing and can more fully use the large and complex quantity of data generated during the care of patients with HF.
Post-cardiac arrest temporal evolution of left ventricular function in a rat model: speckle-tracking echocardiography and cardiac circulating biomarkers
Authors: De Giorgio Daria , Olivari Davide , Fumagalli Francesca , Novelli Deborah , Cerrato Marianna , Motta Francesca , Ristagno Giuseppe , Latini Roberto , Staszewsky Lidia
Published: February 2024

Aims

There is little information from experimental studies regarding the evolution of post-resuscitation cardiac arrest [post-return of spontaneous circulation (post-ROSC)] myocardial dysfunction during mid-term follow-up. For this purpose, we assessed left ventricular (LV) function and circulating cardiac biomarkers at different time points in a rat model of cardiac arrest (CA).

Methods and results

Rats were divided into two groups: control and post-ROSC rats. Eight minutes of untreated ventricular fibrillation were followed by 8 min of cardiopulmonary resuscitation. Conventional and speckle-tracking echocardiographic (STE) parameters and cardiac circulating biomarkers concentrations were assessed, at 3, 4, 72, and 96 h post-ROSC. At 3 and 4 h post-ROSC, LV systolic function was severely impaired, and high-sensitivity cardiac troponin T and N-terminal pro-atrial natriuretic peptide (NT-proANP) plasma concentrations were significantly increased, compared with control rats (P < 0.0001 for all). At 72 and 96 h post-ROSC, LV ejection fraction (LVEF) normalized. At 96 h, the following variables were significantly different from control rats: early trans-mitral peak velocity, 56.8 ± 3.1 vs. 87.8 ± 3.8 cm/s, P < 0.0001; late trans-mitral peak velocity, 50.6 ± 4.7 vs. 73.7 ± 4.2 cm/s, P < 0.0001; mean s′ wave velocity, 4.6 ± 0.3 vs. 5.9 ± 0.3 cm/s, P < 0.0001, global longitudinal strain (GLS) −7.5 ± 0.5 and vs. −11 ± 1.2%, P < 0.01; GLS rate (GLSR) −0.9 ± 0.4 and −2.3 ± 0.2 1/s, P < 0.01; and NT-proANP concentration, 2.5 (0.2; 6.0) vs. 0.4 (0.01; 1.0) nmol/L, P < 0.01.

Conclusion

s′ velocity, GLS, and GLSR indicated that LV systolic function was still impaired 96 h post-ROSC. These findings agree with NT-proANP concentrations, which continue to be high. Normalization of LVEF supports the use of STE for its greater sensitivity for monitoring post-CA cardiac function. Further investigations are needed to provide evidence of the post-ROSC LV diastolic function pattern.
Divergence in evolutionary potential of life history traits among wild populations is predicted by differences in climatic conditions
Authors: Chantepie Stéphane , Charmantier Anne , Delahaie Boris , Adriaensen Frank , Matthysen Erik , Visser Marcel E , Álvarez Elena , Barba Emilio , Orell Markku , Sheldon Ben , Ivankina Elena , Kerimov Anvar , Lavergne Sébastien , Teplitsky Céline
Published: February 2024

Short-term adaptive evolution represents one of the primary mechanisms allowing species to persist in the face of global change. Predicting the adaptive response at the species level requires reliable estimates of the evolutionary potential of traits involved in adaptive responses, as well as understanding how evolutionary potential varies across a species’ range. Theory suggests that spatial variation in the fitness landscape due to environmental variation will directly impact the evolutionary potential of traits. However, empirical evidence on the link between environmental variation and evolutionary potential across a species range in the wild is lacking. In this study, we estimate multivariate evolutionary potential (via the genetic variance–covariance matrix, or G-matrix) for six morphological and life history traits in 10 wild populations of great tits (Parus major) distributed across Europe. The G-matrix significantly varies in size, shape, and orientation across populations for both types of traits. For life history traits, the differences in G-matrix are larger when populations are more distant in their climatic niche. This suggests that local climates contribute to shaping the evolutionary potential of phenotypic traits that are strongly related to fitness. However, we found no difference in the overall evolutionary potential (i.e., G-matrix size) between populations closer to the core or the edge of the distribution area. This large-scale comparison of G-matrices across wild populations emphasizes that integrating variation in multivariate evolutionary potential is important to understand and predict species’ adaptive responses to new selective pressures.
Telepsychology revolution in the mental health care delivery: a global overview of emerging clinical and legal issues
Authors: Sablone Sara , Bellino Mara , Lagona Valeria , Franco Tamara Patrizia , Groicher Matthew , Risola Roberta , Violante Maria Grazia , Grattagliano Ignazio
Published: February 2024

Since the outbreak of the COVID-19 pandemic, remote healthcare delivery by technological devices has become a growing practice. It represented an unprecedented change in personal and professional activities, allowing health specialists to continue working online by assisting their patients from home. Psychological practice greatly benefited from this innovation, guaranteeing diagnostic and therapeutic effectiveness through cyber counseling. However, in many countries there have been no enactments of specific laws nor adaptations of the professional deontological code aimed at regulating this new psychological practice dimension, generally defined as telepsychology. This article aims to briefly review the scientific literature on this tool’s effectiveness and especially analyze the legal and operational framework in which telepsychology has been to date practiced in Italy and other national realities, thus providing a global overview that may be useful to understand how to improve this valuable but still immature practice.

Key points
The evolution and scope of Medicaid Section 1115 demonstrations to address nutrition: a US survey
Authors: Hanson Erika , Albert-Rozenberg Daniel , Garfield Kathryn M , Broad Leib Emily , Ridberg Ronit A , Hager Kurt , Mozaffarian Dariush
Published: February 2024

Poor nutrition and food insecurity are drivers of poor health, diet-related diseases, and health disparities in the US. State Medicaid Section 1115 demonstration waivers offer opportunities to pilot food-based initiatives to address health outcomes and disparities. Several states are now leveraging 1115 demonstrations, but the scope and types of utilization remain undefined. To fill this gap, we conducted a systematic analysis of state Medicaid Section 1115 applications and approvals available on Medicaid.gov through July 1, 2023. We found that 19 approved and pending 1115 waivers address nutrition, with 11 submitted or approved since 2021. Fifteen states provide or propose to provide screening for food insecurity, referral to food security programs, and/or reporting on food security as an evaluation metric. Thirteen provide or propose to provide coverage of nutrition education services. Ten provide or propose to provide direct intervention with healthy food. The primary target populations of these demonstrations are individuals with chronic diet-sensitive conditions, mental health or substance use disorders, and/or who are pregnant or postpartum. Since 2021, state utilization of Medicaid 1115 demonstrations to address nutrition has accelerated in pace, scope, and population coverage. These findings and trends have major implications for addressing diet-related health and health equity in the United States.
Comparing Medicare plan selection among beneficiaries with and without a history of cancer
Authors: Jazowski Shelley A , Achola Emma M , Nicholas Lauren H , Wood William A , Friese Christopher R , Dusetzina Stacie B
Published: February 2024

Individuals aging into Medicare must choose among plans that vary in their scope of benefits, access to health care providers, and exposure to out-of-pocket expenses. When faced with complex coverage decisions, it is unclear whether older adults consider their experiences with prior serious illness or current medical conditions. We estimated the association between a self-reported history of cancer and initial plan selection among 3811 Health and Retirement Study participants aging into Medicare between 2008 and 2020. The proportion of individuals with and without a history of cancer who chose Medicare Advantage was similar; however, the probability of selecting traditional Medicare plus supplemental coverage was 8.03 percentage points (95% confidence interval, 2.99–13.07) higher for respondents with a history of cancer compared with those without a history of cancer. Individuals with a history of cancer may have accounted for their previous experiences with high-cost health care services and prioritized plans with robust benefits (eg, greater financial protections). Raising awareness of and enhancing educational resources could ensure that older adults select plans that meet their current and evolving health care needs.
Why rights should not be considered (entirely) constricted and why identities are not exactly imagined: A reply to Alma Begicevic and Jennifer Balint
Authors: Sahadžić Maja
Published: February 2024

In their recent article “Constricted Rights and Imagined Identities: Peace and Accountability Processes and Constitution-Making in Bosnia and Herzegovina,” Alma Begicevic and Jennifer Balint argue that underlying reasons for the seemingly sudden establishment of the complex constitutional arrangements in Bosnia and Herzegovina (BH) are associated with the abrupt adoption of the Dayton Peace Agreement and its Annex IV (the Constitution of BH) that introduced the ethnoterritorial setup and the lack of accountability of the neighboring countries for the atrocities committed during the Bosnian War. As a consequence, the country cannot effectively (re)construct a nation state and, instead, suffers from a lack of homogeneity. Moreover, post-conflict institutional and procedural arrangements appear to be comparatively uncharted territory. This article scrutinizes and counters these claims with the thesis that territorial accommodation of differences is a rather frequent approach in fragmenting systems with competing identities. To substantiate the thesis, the article draws on the concepts of cohesion and stability linked to adaptiveness and coordination. It then analyzes the role of the power ratio during the Bosnian War and the internal building blocks that contributed to the ethnoterritorial setup. Finally, the article focuses on the concept of equality in complex systems linked to mutual respect, solidarity, and trust to analyze the necessity for plural equality in BH.