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1.
Pediatr Transplant ; 28(7): e14856, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39267498

RESUMO

BACKGROUND: Two common indications for pediatric heart transplantation are congenital heart disease and cardiomyopathy. Prior studies suggest differences in chronotropy on cardiopulmonary exercise testing outcomes depending on indication for heart transplantation. We aimed to determine whether the number of pretransplant sternotomies is associated with differences in heart rate response during exercise testing. METHODS: A retrospective analysis of our institutional pediatric heart transplant data between 2004 and 2022 was performed. Patients were categorized by indication for transplantation into a cardiomyopathy (CM) group if they had a congenital or acquired cardiomyopathy or a congenital heart disease (CHD) group including all other forms of congenital cardiac anatomic abnormalities. RESULTS: CHD patients (n = 40) differed from CM patients (n = 53) by mean number of sternotomies prior to transplant (2.4 ± 1.8 vs. 0.5 ± 0.9, p < 0.001). There were no significant differences in echocardiographic function or catheterization hemodynamics. In cardiopulmonary exercise testing performance, the congenital heart disease group had a significantly higher resting heart rate (91.8 ± 11.2 vs. 86.4 ± 10.2 bpm, p = 0.019), lower percent predicted age-predicted maximal heart rate achieved (78.3 ± 8.5% vs. 83.2 ± 11.4%, p = 0.032), and lower heart rate reserve (68.6 ± 19.8 vs. 84.4 ± 24.0 bpm, p = 0.001) despite a similar age and average time from transplantation. Regression analysis confirmed number of pretransplant sternotomies as a main predictor of heart rate metrics. CONCLUSIONS: There is greater chronotropic incompetence in patients who underwent transplantation due to congenital heart disease compared to cardiomyopathy. The groups differ significantly by number of sternotomies, potentially supporting the hypothesis that prior surgical disruption of cardiac innervation may cause decreased chronotropic response to exercise following transplantation.


Assuntos
Cardiomiopatias , Teste de Esforço , Cardiopatias Congênitas , Frequência Cardíaca , Transplante de Coração , Humanos , Cardiopatias Congênitas/cirurgia , Cardiopatias Congênitas/fisiopatologia , Masculino , Feminino , Estudos Retrospectivos , Criança , Frequência Cardíaca/fisiologia , Cardiomiopatias/fisiopatologia , Cardiomiopatias/etiologia , Cardiomiopatias/diagnóstico , Adolescente , Pré-Escolar , Lactente , Exercício Físico/fisiologia
3.
Pediatr Cardiol ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39153090

RESUMO

Studies have suggested that pediatric patients with heart transplants (HT) due to congenital heart disease (CHD) perform differently on cardiopulmonary exercise testing compared to pediatric patients with HT due to cardiomyopathy (CM). However, it is not known if this relationship changes over time. The aim of this study was to examine the differences in cardiopulmonary exercise test (CPET) parameters over time between patients with HT due to CHD versus CM. A large single-institution CPET database was used for this study. We conducted a retrospective cohort study of 250 total CPETs from 93 unique patients, examining how patients with HT due to CHD (109 CPETs, 40 unique patients) differed in CPET performance from patients with HT due to CM (141 CPETs, 53 unique patients) from < 2 years post-HT, 2 to < 6 years post-HT, and ≥ 6 years post-HT. There were no differences between patients with HT due to CHD compared to CM in CPETs performed < 2 years post-HT. In CPETs performed 2 to < 6 years post-HT, the CM group had higher maximal HR and percentage of age-predicted maximal heart rate (APMHR) achieved. At ≥ 6 years post-HT, the CM group continued to have higher maximal HR and percentage of APMHR achieved, but also improved HR recovery at one minute. Initial indication for transplant may affect performance on CPETs post-transplant. Patients with HT due to CM have improved chronotropic measures compared to patients with HT due to CHD and these differences are more pronounced with increased time post-HT.

4.
Nat Ecol Evol ; 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39209981

RESUMO

Ecosystem functioning depends on biodiversity at multiple trophic levels, yet relationships between multitrophic diversity and ecosystem multifunctionality have been poorly explored, with studies often focusing on individual trophic levels and functions and on specific ecosystem types. Here, we show that plant diversity can affect ecosystem functioning both directly and by affecting other trophic levels. Using data on 13 trophic groups and 13 ecosystem functions from two large biodiversity experiments-one representing temperate grasslands and the other subtropical forests-we found that plant diversity increases multifunctionality through elevated multitrophic diversity. Across both experiments, the association between multitrophic diversity and multifunctionality was stronger than the relationship between the diversity of individual trophic groups and multifunctionality. Our results also suggest that the role of multitrophic diversity is greater in forests than in grasslands. These findings imply that, to promote sustained ecosystem multifunctionality, conservation planning must consider the diversity of both plants and higher trophic levels.

5.
Ann Vasc Surg ; 108: 393-402, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39019257

RESUMO

BACKGROUND: Carotid endarterectomy (CEA) is a well-established standard therapy for patients with symptomatic or asymptomatic high-grade carotid stenosis. The aim of carotid endarterectomy is to decrease the risk of stroke and avoid relevant functional loss. However, carotid endarterectomy is known to be associated with hemodynamic dysregulation. In this study we compared eversion CEA (E-CEA) and conventional CEA (C-CEA) regarding postoperative blood pressure values as well as preoperative and postoperative baroreceptor sensitivity in the first 7 days after surgery. The aim was to find possible factors influencing changes in baroreceptor sensitivity. METHODS: Patients (111 patients were enrolled, of which 50 patients received C-CEA and 61 patients E-CEA) were prospectively enrolled in this study. For the measurement of baroreceptor sensitivity, a noninvasive Finometer measuring device from Finapres Medical System B.V. (Amsterdam, The Netherlands) was used. Measurements were performed 1 day before surgery (PRE), directly after surgery (F1), on day 1 (F2), day 2 (F3), and on day 7 (F4) postoperatively. RESULTS: Postoperative blood pressure values were significantly higher in the E-CEA group on the day of surgery (F1) (P < 0.001) and on day 1 (F2) (P < 0.001). From day 2 (F3, F4) postoperatively, no significant difference was found between the 2 groups. The invasive blood pressure measurement in the postoperative recovery room showed significantly higher systolic blood pressure values in the E-CEA group (P = 0.001). The need of acute antihypertensive therapy was significantly higher in the recovery room in the E-CEA group (P = 0.020). With regard to changes in baroreceptor sensitivity, significantly lower baroreceptor sensitivity (BRS) values were recorded in the E-CEA group at 1 day (F2) postoperatively (P = 0.005). The regression analysis showed that the applied surgical technique and the patient's age were significant factors influencing changes in baroreceptor sensitivity. CONCLUSIONS: In this study we could confirm higher blood pressure levels after E-CEA in the first 2 days after surgery. Additionally, we identified 22 factors possibly influencing baroreceptor sensitivity: surgical technique and age. Based on the data obtained in this study, hemodynamic dysregulation after CEA (E-CEA, C-CEA) is temporary and short-term. Already after the second postoperative day, there was no significant difference between the E-CEA and E-CEA groups, this effect remained stable after 7 days.


Assuntos
Barorreflexo , Pressão Sanguínea , Estenose das Carótidas , Endarterectomia das Carótidas , Pressorreceptores , Humanos , Endarterectomia das Carótidas/efeitos adversos , Masculino , Feminino , Idoso , Estenose das Carótidas/cirurgia , Estenose das Carótidas/fisiopatologia , Estudos Prospectivos , Pressorreceptores/fisiopatologia , Resultado do Tratamento , Fatores de Tempo , Pessoa de Meia-Idade , Fatores de Risco , Idoso de 80 Anos ou mais
7.
Glob Chang Biol ; 30(3): e17225, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38462708

RESUMO

It is well known that biodiversity positively affects ecosystem functioning, leading to enhanced ecosystem stability. However, this knowledge is mainly based on analyses using single ecosystem functions, while studies focusing on the stability of ecosystem multifunctionality (EMF) are rare. Taking advantage of a long-term grassland biodiversity experiment, we studied the effect of plant diversity (1-60 species) on EMF over 5 years, its temporal stability, as well as multifunctional resistance and resilience to a 2-year drought event. Using split-plot treatments, we further tested whether a shared history of plants and soil influences the studied relationships. We calculated EMF based on functions related to plants and higher-trophic levels. Plant diversity enhanced EMF in all studied years, and this effect strengthened over the study period. Moreover, plant diversity increased the temporal stability of EMF and fostered resistance to reoccurring drought events. Old plant communities with shared plant and soil history showed a stronger plant diversity-multifunctionality relationship and higher temporal stability of EMF than younger communities without shared histories. Our results highlight the importance of old and biodiverse plant communities for EMF and its stability to extreme climate events in a world increasingly threatened by global change.


Assuntos
Ecossistema , Pradaria , Biodiversidade , Plantas , Solo
8.
Phys Imaging Radiat Oncol ; 29: 100547, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38390589

RESUMO

Background and Purpose: The lack of dedicated tools in commercial planning systems currently restricts efficient review and planning for re-irradiation. The aim of this study was to develop an automated re-irradiation planning framework based on cumulative doses. Materials and Methods: We performed a retrospective study of 14 patients who received spine SBRT re-irradiation near a previously irradiated treatment site. A fully-automated workflow, DART (Dose Accumulation-based Re-irradiation Tool), was implemented within Eclipse by leveraging a combination of a dose accumulation script and a proprietary automated optimization algorithm. First, we converted the prior treatment dose into equivalent dose in 2 Gy fractions (EQD2) and mapped it to the current anatomy, utilizing deformable image registration. Subsequently, the intersection of EQD2 isodose lines with relevant organs at risk defines a series of optimization structures. During plan optimization, the residual allowable dose at a specified tissue tolerance was treated as a hard constraint. Results: All DART plans met institutional physical and cumulative constraints and passed plan checks by qualified medical physicists. DART demonstrated significant improvements in target coverage over clinical plans, with an average increase in PTV D99% and V100% of 2.3 Gy [range -0.3-7.7 Gy] and 3.4 % [range -0.4 %-7.6 %] (p < 0.01, paired t-test), respectively. Moreover, high-dose spillage (>105 %) outside the PTV was reduced by up to 7 cm3. The homogeneity index for DART plans was improved by 19 % (p < 0.001). Conclusions: DART provides a powerful framework to achieve more tailored re-irradiation plans by accounting for dose distributions from the previous treatments. The superior plan quality could improve the therapeutic ratio for re-irradiation patients.

9.
J Pediatr ; 268: 113964, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38369240

RESUMO

OBJECTIVE: To evaluate the effect of neighborhood-level characteristics on cardiorespiratory fitness (CRF) via peak oxygen consumption (VO2peak) for healthy pediatric patients. STUDY DESIGN: The institutional cardiopulmonary exercise testing (CPET) database was analyzed retrospectively. All patients aged ≤ 18 years without a diagnosis of cardiac disease and with a maximal effort CPET were included. Patients were divided into three self-identified racial categories: White, Black, and Latinx. The Child Opportunity Index (COI) 2.0 was used to analyze social determinants of health. CRF was evaluated based on COI quintiles and race. Assessment of the effect of COI on racial disparities in CRF was performed using ANCOVA. RESULTS: A total of 1753 CPETs met inclusion criteria. The mean VO2peak was 42.1 ± 9.8 mL/kg/min. The VO2peak increased from 39.1 ± 9.6 mL/kg/min for patients in the very low opportunity cohort to 43.9 ± 9.4 mL/kg/min for patients in the very high opportunity cohort. White patients had higher percent predicted VO2peak compared with both Black and Latinx patients (P < .01 for both comparisons). The racial differences in CRF were no longer significant when adjusting for COI. CONCLUSION: In a large pediatric cohort, COI was associated with CRF. Racial disparities in CRF are reduced when accounting for modifiable risk factors.


Assuntos
Aptidão Cardiorrespiratória , Teste de Esforço , Consumo de Oxigênio , Adolescente , Criança , Feminino , Humanos , Masculino , Negro ou Afro-Americano/estatística & dados numéricos , Aptidão Cardiorrespiratória/fisiologia , Disparidades nos Níveis de Saúde , Hispânico ou Latino/estatística & dados numéricos , Consumo de Oxigênio/fisiologia , Características de Residência , Estudos Retrospectivos , Determinantes Sociais da Saúde , Brancos
10.
J Appl Clin Med Phys ; 25(4): e14300, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38386967

RESUMO

PURPOSE: The aim of this study was to characterize a second-generation wide-detector dual-layer spectral computed tomography (CT) system for material quantification accuracy, acquisition parameter and patient size dependencies, and tissue characterization capabilities. METHODS: A phantom with multiple tissue-mimicking and material-specific inserts was scanned with a dual-layer spectral detector CT using different tube voltages, collimation widths, radiation dose levels, and size configurations. Accuracy of iodine density maps and virtual monoenergetic images (MonoE) were investigated. Additionally, differences between conventional and MonoE 70 keV images were calculated to evaluate acquisition parameter and patient size dependencies. To demonstrate material quantification and differentiation, liver-mimicking inserts with adipose and iron were analyzed with a two-base decomposition utilizing MonoE 50 and 150 keV, and root mean square error (RMSE) for adipose and iron content was reported. RESULTS: Measured inserts exhibited quantitative accuracy across a wide range of MonoE levels. MonoE 70 keV images demonstrated reduced dependence compared to conventional images for phantom size (1 vs. 27 HU) and acquisition parameters, particularly tube voltage (4 vs. 37 HU). Iodine density quantification was successful with errors ranging from -0.58 to 0.44 mg/mL. Similarly, inserts with different amounts of adipose and iron were differentiated, and the small deviation in values within inserts corresponded to a RMSE of 3.49 ± 1.76% and 1.67 ± 0.84 mg/mL for adipose and iron content, respectively. CONCLUSION: The second-generation dual-layer CT enables acquisition of quantitatively accurate spectral data without compromises from differences in patient size and acquisition parameters.


Assuntos
Iodo , Tomografia Computadorizada por Raios X , Humanos , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X/métodos , Imagens de Fantasmas , Obesidade , Ferro
11.
Med Phys ; 51(2): 1405-1414, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37449537

RESUMO

BACKGROUND: Quality assurance of deformable image registration (DIR) is challenging because the ground truth is often unavailable. In addition, current approaches that rely on artificial transformations do not adequately resemble clinical scenarios encountered in adaptive radiotherapy. PURPOSE: We developed an atlas-based method to create a variety of patient-specific serial digital phantoms with CBCT-like image quality to assess the DIR performance for longitudinal CBCT imaging data in adaptive lung radiotherapy. METHODS: A library of deformations was created by extracting the longitudinal changes observed between a planning CT and weekly CBCT from an atlas of lung radiotherapy patients. The planning CT of an inquiry patient was first deformed by mapping the deformation pattern from a matched atlas patient, and subsequently appended with CBCT artifacts to imitate a weekly CBCT. Finally, a group of digital phantoms around an inquiry patient was produced to simulate a series of possible evolutions of tumor and adjacent normal structures. We validated the generated deformation vector fields (DVFs) to ensure numerically and physiologically realistic transformations. The proposed framework was applied to evaluate the performance of the DIR algorithm implemented in the commercial Eclipse treatment planning system in a retrospective study of eight inquiry patients. RESULTS: The generated DVFs were inverse consistent within less than 3 mm and did not exhibit unrealistic folding. The deformation patterns adequately mimicked the observed longitudinal anatomical changes of the matched atlas patients. Worse Eclipse DVF accuracy was observed in regions of low image contrast or artifacts. The structure volumes exhibiting a DVF error magnitude of equal or more than 2 mm ranged from 24.5% (spinal cord) to 69.2% (heart) and the maximum DVF error exceeded 5 mm for all structures except the spinal cord. Contour-based evaluations showed a high degree of alignment with dice similarity coefficients above 0.8 in all cases, which underestimated the overall DVF accuracy within the structures. CONCLUSIONS: It is feasible to create and augment digital phantoms based on a particular patient of interest using multiple series of deformation patterns from matched patients in an atlas. This can provide a semi-automated procedure to complement the quality assurance of CT-CBCT DIR and facilitate the clinical implementation of image-guided and adaptive radiotherapy that involve longitudinal CBCT imaging studies.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Estudos Retrospectivos , Tomografia Computadorizada de Feixe Cônico/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Imagens de Fantasmas , Pulmão/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
12.
ACS Appl Mater Interfaces ; 15(29): 35600-35610, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37459562

RESUMO

Functional materials feature hierarchical microstructures that define their unique set of properties. The prediction and tailoring of these require a multiscale knowledge of the mechanistic interaction of microstructure and property. An important material in this respect is biodegradable magnesium alloys used for implant applications. To correlate the relationship between the microstructure and the nonlinear degradation process, high-resolution in situ three-dimensional (3D) imaging experiments must be performed. For this purpose, a novel experimental flow cell is presented which allows for the in situ 3D-nano imaging of the biodegradation process of materials with nominal resolutions below 100 nm using nanofocused hard X-ray radiation from a synchrotron source. The flow cell setup can operate under adjustable physiological and hydrodynamic conditions. As a model material, the biodegradation of thin Mg-4Ag wires in simulated body fluid under physiological conditions and a flow rate of 1 mL/min is studied. The use of two full-field nanotomographic imaging techniques, namely transmission X-ray microscopy and near-field holotomography, is compared, revealing holotomography as the superior imaging technique for this purpose. Additionally, the importance of maintaining physiological conditions is highlighted by the preliminary results. Supporting measurements using electron microscopy to investigate the chemical composition of the samples after degradation are performed.


Assuntos
Ligas , Reatores Biológicos , Ligas/química
13.
Biom J ; 65(8): e2100408, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37439440

RESUMO

Count data with an excess of zeros are often encountered when modeling infectious disease occurrence. The degree of zero inflation can vary over time due to nonepidemic periods as well as by age group or region. A well-established approach to analyze multivariate incidence time series is the endemic-epidemic modeling framework, also known as the HHH approach. However, it assumes Poisson or negative binomial distributions and is thus not tailored to surveillance data with excess zeros. Here, we propose a multivariate zero-inflated endemic-epidemic model with random effects that extends HHH. Parameters of both the zero-inflation probability and the HHH part of this mixture model can be estimated jointly and efficiently via (penalized) maximum likelihood inference using analytical derivatives. We found proper convergence and good coverage of confidence intervals in simulation studies. An application to measles counts in the 16 German states, 2005-2018, showed that zero inflation is more pronounced in the Eastern states characterized by a higher vaccination coverage. Probabilistic forecasts of measles cases improved when accounting for zero inflation. We anticipate zero-inflated HHH models to be a useful extension also for other applications and provide an implementation in an R package.


Assuntos
Sarampo , Modelos Estatísticos , Humanos , Fatores de Tempo , Simulação por Computador , Sarampo/epidemiologia , Sarampo/prevenção & controle , Alemanha/epidemiologia , Distribuição de Poisson
14.
Z Med Phys ; 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37353464

RESUMO

We present a multi-stage and multi-resolution deformable image registration framework for image-guidance at a small animal proton irradiation platform. The framework is based on list-mode proton radiographies acquired at different angles, which are used to deform a 3D treatment planning CT relying on normalized mutual information (NMI) or root mean square error (RMSE) in the projection domain. We utilized a mouse X-ray micro-CT expressed in relative stopping power (RSP), and obtained Monte Carlo simulations of proton images in list-mode for three different treatment sites (brain, head and neck, lung). Rigid transformations and controlled artificial deformation were applied to mimic position misalignments, weight loss and breathing changes. Results were evaluated based on the residual RMSE of RSP in the image domain including the comparison of extracted local features, i.e. between the reference micro-CT and the one transformed taking into account the calculated deformation. The residual RMSE of the RSP showed that the accuracy of the registration framework is promising for compensating rigid (>97% accuracy) and non-rigid (∼95% accuracy) transformations with respect to a conventional 3D-3D registration. Results showed that the registration accuracy is degraded when considering the realistic detector performance and NMI as a metric, whereas the RMSE in projection domain is rather insensitive. This work demonstrates the pre-clinical feasibility of the registration framework on different treatment sites and its use for small animal imaging with a realistic detector. Further computational optimization of the framework is required to enable the use of this tool for online estimation of the deformation.

15.
Environ Int ; 177: 108000, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37285713

RESUMO

BACKGROUND AND PURPOSE: Aluminum can be released into food by aluminum-containing food-contact materials (Al-FCM) during preparation or storage. There is considerable concern that extra aluminum intake may have negative effects on public health, especially with regard to its high background exposure and neurotoxic properties of aluminum in high exposures. Human in-vivo data on the additional aluminum load from Al-FCM, however, are lacking. As such, the objective of this study was to explore whether the consumption of a diet highly exposed to such products leads to an increased systemic Al load in real-world conditions. MATERIALS AND METHODS: An exploratory, single-arm intervention study with a partially standardized diet was designed and carried out with 11participants. The same 10-day sequence of dishes was repeated three times. Participants were exposed to Al-FCM from Days 11 to 20, whereas control-phase meals were prepared without Al-FCM during the first and last 10-day periods. Spot urine samples were collected each morning and evening and analyzed for their aluminum concentration; appropriate contamination countermeasures were taken. PRINCIPAL RESULTS: Urinary aluminum excretion showed a strong dependency on the creatinine concentration in urine and required adjustment in further analyses. The creatinine-adjusted aluminum excretion during the exposure phase (median 1.98 µg/g creatinine) was higher than in both control phases (1.78 µg/g creatinine each). Two different mixed-effects regression models showed a significant effect in the exposure phase. Considering a discrete time effect, the creatinine-adjusted mean increase in the exposure phase was estimated to be 0.19 µg/L (95% CI: 0.07-0.31; p = 0.0017). MAJOR CONCLUSIONS: This study demonstrated a measurable but fully reversible additional Al burden in humans from subacute Al-FCM exposure under real-world conditions. The estimated increase from Al-FCM corresponds to 8% of the baseline concentration. These data enable a more robust assessment of human health risks by Al-FCM.


Assuntos
Alumínio , Síndromes Neurotóxicas , Humanos , Alumínio/toxicidade , Alumínio/urina , Creatinina , Dieta
16.
ArXiv ; 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37205269

RESUMO

X-ray phase-contrast imaging offers enhanced sensitivity for weakly-attenuating materials, such as breast and brain tissue, but has yet to be widely implemented clinically due to high coherence requirements and expensive x-ray optics. Speckle-based phase contrast imaging has been proposed as an affordable and simple alternative; however, obtaining high-quality phase-contrast images requires accurate tracking of sample-induced speckle pattern modulations. This study introduced a convolutional neural network to accurately retrieve sub-pixel displacement fields from pairs of reference (i.e., without sample) and sample images for speckle tracking. Speckle patterns were generated utilizing an in-house wave-optical simulation tool. These images were then randomly deformed and attenuated to generate training and testing datasets. The performance of the model was evaluated and compared against conventional speckle tracking algorithms: zero-normalized cross-correlation and unified modulated pattern analysis. We demonstrate improved accuracy (1.7 times better than conventional speckle tracking), bias (2.6 times), and spatial resolution (2.3 times), as well as noise robustness, window size independence, and computational efficiency. In addition, the model was validated with a simulated geometric phantom. Thus, in this study, we propose a novel convolutional-neural-network-based speckle-tracking method with enhanced performance and robustness that offers improved alternative tracking while further expanding the potential applications of speckle-based phase contrast imaging.

17.
Sci Adv ; 9(16): eadf4049, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37083532

RESUMO

An integrated textile electronic system is reported here, enabling a truly free form factor system via textile manufacturing integration of fiber-based electronic components. Intelligent and smart systems require freedom of form factor, unrestricted design, and unlimited scale. Initial attempts to develop conductive fibers and textile electronics failed to achieve reliable integration and performance required for industrial-scale manufacturing of technical textiles by standard weaving technologies. Here, we present a textile electronic system with functional one-dimensional devices, including fiber photodetectors (as an input device), fiber supercapacitors (as an energy storage device), fiber field-effect transistors (as an electronic driving device), and fiber quantum dot light-emitting diodes (as an output device). As a proof of concept applicable to smart homes, a textile electronic system composed of multiple functional fiber components is demonstrated, enabling luminance modulation and letter indication depending on sunlight intensity.

18.
Quant Imaging Med Surg ; 13(2): 924-934, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36819257

RESUMO

Background: To determine the spectral accuracy in detector-based dual-energy CT (DECT) at 100 kVp and wide (8 cm) collimation width for dose levels and object sizes relevant to pediatric imaging. Methods: A spectral CT phantom containing tissue-equivalent materials and iodine inserts of varying concentrations was scanned on the latest generation detector-based DECT system. Two 3D-printed extension rings were used to mimic varying pediatric patient sizes. Scans were performed at 100 and 120 kVp, 4 and 8 cm collimation widths, and progressively reduced radiation dose levels, down to 0.9 mGy CTDIvol. Virtual mono-energetic, iodine density, effective atomic number, and electron density results were quantified and compared to their expected values for all acquisition settings and phantom sizes. Results: DECT scans at 100 kVp provided highly accurate spectral results; however, a size dependence was observed for iodine quantification. For the medium phantom configuration (15 cm diameter), measurement errors in iodine density, effective atomic number, and electron density (ED) were below 0.3 mg/mL, 0.2 and 1.8 %EDwater, respectively. The average accuracy was slightly different from scans at 120 kVp; however, not statistically significant for all configurations. Collimation width had no substantial impact. Spectral results were accurate and reliable for radiation exposures down to 0.9 mGy CTDIvol. Conclusions: Detector-based DECT at 100 kVp can provide on-demand or retrospective spectral information with high accuracy even at extremely low doses, thereby making it an attractive solution for pediatric imaging.

20.
BMC Geriatr ; 22(1): 1001, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36577973

RESUMO

BACKGROUND: Severe dementia is one of the most challenging conditions when caring for people in nursing homes. A manualised non-pharmacological, psychosocial group intervention especially adapted to the needs of people with severe dementia (PWSDs) is currently still lacking. To close this gap, we adapted the evidence-based multicomponent non-pharmacological MAKS intervention (Motor stimulation, ADL stimulation, Cognitive [german: Kognitive] stimulation, and Social functioning in a group setting) to the special needs of PWSDs called the MAKS-s intervention, where the s stands for severe dementia. METHODS: In a prospective, multicentre, cluster-randomised trial with a waitlist control group design, 26 nursing homes comprising 152 PWSDs were randomly assigned to either the MAKS-s intervention group (IG) or control group (CG) - 121 PWSDs were still alive after the 6-month intervention period (t6) and included in the intention-to-treat (ITT) sample. The two primary outcomes, behavioural and psychological symptoms (BPSDs, measured with NPI-NH) and quality of life (QoL, measured with QUALIDEM), and the secondary outcome, activities of daily living (ADLs, measured with ADCS-ADL-sev), were assessed at baseline (t0) and at t6. Mixed ANOVAs were computed to investigate possible effects of the MAKS-s intervention on the outcomes. RESULTS: In the ITT sample, BPSDs and QoL did not change significantly over time, and group assignment did not affect them, although the IG participants had significantly better overall QoL than the CG participants. ADLs decreased significantly over time, but group assignment did not affect them. Analyses in the per protocol (PP) sample showed comparable results, with the exception that the IG participants showed a significantly greater increase in BPSDs than the CG participants did. DISCUSSION: Under the situational conditions of the Covid-19 pandemic, no beneficial effects of the MAKS-s intervention on BPSDs, QoL, or ADLs were observed. This finding also means that under 'normal circumstances' (i.e., if there had been no pandemic), we could not make any statements about the effect or non-effect of MAKS-s. In order to be able to address the hypotheses formulated here, the study will have to be repeated incorporating helpful experiences of the present study. TRIAL REGISTRATION: https://doi.org/10.1186/ISRCTN15722923 (Registered prospectively, 07. August 2019).


Assuntos
COVID-19 , Demência , Humanos , Qualidade de Vida , Atividades Cotidianas , Pandemias , Estudos Prospectivos , Demência/epidemiologia , Demência/terapia , Demência/psicologia , Casas de Saúde
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