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1.
Nanomaterials (Basel) ; 14(13)2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38998740

ABSTRACT

Ice formation on aircraft surfaces poses significant safety risks, and current detection systems often struggle to provide accurate, real-time predictions. This paper presents the development and comprehensive evaluation of a smart ice control system using a suite of machine learning models. The system utilizes various sensors to detect temperature anomalies and signal potential ice formation. We trained and tested supervised learning models (Logistic Regression, Support Vector Machine, and Random Forest), unsupervised learning models (K-Means Clustering), and neural networks (Multilayer Perceptron) to predict and identify ice formation patterns. The experimental results demonstrate that our smart system, driven by machine learning, accurately predicts ice formation in real time, optimizes deicing processes, and enhances safety while reducing power consumption. This solution holds the potential for improving ice detection accuracy in aviation and other critical industries requiring robust predictive maintenance.

2.
Int J Mol Sci ; 25(11)2024 May 21.
Article in English | MEDLINE | ID: mdl-38891788

ABSTRACT

In the process of tissue engineering, several types of stresses can influence the outcome of tissue regeneration. This outcome can be understood by designing hydrogels that mimic this process and studying how such hydrogel scaffolds and cells behave under a set of stresses. Here, a hydrogel formulation is proposed to create biomimetic scaffolds suitable for fibroblast cell culture. Subsequently, we examine the impact of external stresses on fibroblast cells cultured on both solid and porous hydrogels. These stresses included mechanical tension and altered-gravity conditions experienced during the 83rd parabolic flight campaign conducted by the European Space Agency. This study shows distinct cellular responses characterized by cell aggregation and redistribution in regions of intensified stress concentration. This paper presents a new biomimetic hydrogel that fulfills tissue-engineering requirements in terms of biocompatibility and mechanical stability. Moreover, it contributes to our comprehension of cellular biomechanics under diverse gravitational conditions, shedding light on the dynamic cellular adaptations versus varying stress environments.


Subject(s)
Fibroblasts , Hydrogels , Tissue Engineering , Fibroblasts/drug effects , Fibroblasts/metabolism , Fibroblasts/cytology , Hydrogels/chemistry , Tissue Engineering/methods , Cell Culture Techniques/methods , Stress, Mechanical , Biomimetics/methods , Animals , Tissue Scaffolds/chemistry , Biomimetic Materials/chemistry , Biomimetic Materials/pharmacology , Humans , Mice
3.
Global Spine J ; : 21925682241262704, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38874188

ABSTRACT

STUDY DESIGN: A single centre retrospective review. OBJECTIVE: Recent studies have suggested that distal lordosis (L4-S1, DL) remains constant across all pelvic incidence (PI) subgroups, whilst proximal lordosis (L1-L4, PL) varies. We sought to investigate the impact of post-operative DL on adjacent segment disease (ASD) requiring reoperation in patients undergoing lumbar fusion for degenerative conditions. METHODS: Patients undergoing 1-3 level lumbar fusion with the two senior authors between 2007-16 were included. Demographic and radiographic data were recorded. Univariate, multivariate binary logistic regression, and Kaplan Meier survivorship analyses were performed. RESULTS: 335 patients were included in the final analysis. Most had single (67%) or two (31%) level fusions. The mean follow-up was 64-month. Fifty-seven patients (17%) underwent reoperation for ASD at an average of 78-month post-operatively (R group). The R group had a significantly lower mean post-operative DL (27.3 vs 31.1 deg, P < .001) and mean PI (55.5 vs 59.2 deg, P < .05). On univariate analysis, patients with a post-operative DL of <35 deg had higher odds of reoperation for ASD than those with a post-operative DL of ≥35 deg (OR 2.7, P = .016). In the multivariate model, post-operative DL, low/average PI, and spondylolisthesis were all significantly associated with reoperation for ASD. CONCLUSION: This study provides preliminary support to an association between post-operative distal lumbar lordosis and risk of reoperation for ASD in patients undergoing fusions for degenerative conditions. Further multicentre prospective study is needed to independently confirm this association and identify the impact of restoration of physiological distal lumbar lordosis on long term patient outcomes.

4.
NPJ Microgravity ; 10(1): 50, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38693246

ABSTRACT

Periodically, the European Space Agency (ESA) updates scientific roadmaps in consultation with the scientific community. The ESA SciSpacE Science Community White Paper (SSCWP) 9, "Biology in Space and Analogue Environments", focusses in 5 main topic areas, aiming to address key community-identified knowledge gaps in Space Biology. Here we present one of the identified topic areas, which is also an unanswered question of life science research in Space: "How to Obtain an Integrated Picture of the Molecular Networks Involved in Adaptation to Microgravity in Different Biological Systems?" The manuscript reports the main gaps of knowledge which have been identified by the community in the above topic area as well as the approach the community indicates to address the gaps not yet bridged. Moreover, the relevance that these research activities might have for the space exploration programs and also for application in industrial and technological fields on Earth is briefly discussed.

5.
J Orthop Case Rep ; 14(3): 168-175, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38560320

ABSTRACT

Introduction: Ewing sarcoma (ES) is a malignant and aggressive bony tumor affecting the most common age group of 5-20 years. It constitutes 10%-15% of all bone sarcomas and is the second most common primary malignant bone tumor after osteosarcoma. It usually presents with pain, which is typically constant and progressive in nature. The primary source of pain is due to the instability of the spine to support the weight of the body, the vertebral body's expanding cortices due to the growing mass, compression of nerve roots due to tumour mass, pathologic fractures, spinal cord compression, and invasion of tissue by the tumour mass. Methods: We reviewed the literature on Ewing's Sarcoma of the spine to evaluate its etiology, clinical presentations, differential diagnosis, imaging modalities and management with chemotherapy, radiotherapy, and surgical management. PubMed, EMBASE, Google Scholar and Cochrane key articles were searched. Keywords like 'Ewing's Sarcoma,' 'Spine,' 'etiology,' 'treatment,' 'surgical management,' and 'en bloc resection' were used. Discussion: The current management of Ewing's sarcoma of the spine usually involves three primary modalities: combination chemotherapy, surgery and/or radiotherapy. Recent improvements in combination chemotherapy (vincristine, doxorubicin, cyclophosphamide +/- Ifosfamide and etoposide) are among the most significant factors for improving survival. Also, recent advancements in radiotherapy, instrumentation, and fusion techniques in surgical management have been demonstrated to improve local disease control and overall survival. Conclusion: Primary Ewing sarcoma of the spine is a rare condition affecting the most common age group of 5-20 years, accounting for 1-3 cases/million/year. About 5 % of cases have spine involvement. Recent improvements in combination chemotherapy have improved the overall survival rates. Enbloc resection and/or radiotherapy have improved local control of the disease.

6.
Micromachines (Basel) ; 15(4)2024 Apr 07.
Article in English | MEDLINE | ID: mdl-38675315

ABSTRACT

In the context of improving aircraft safety, this work focuses on creating and testing a graphene-based ice detection system in an environmental chamber. This research is driven by the need for more accurate and efficient ice detection methods, which are crucial in mitigating in-flight icing hazards. The methodology employed involves testing flat graphene-based sensors in a controlled environment, simulating a variety of climatic conditions that could be experienced in an aircraft during its entire flight. The environmental chamber enabled precise manipulation of temperature and humidity levels, thereby providing a realistic and comprehensive test bed for sensor performance evaluation. The results were significant, revealing the graphene sensors' heightened sensitivity and rapid response to the subtle changes in environmental conditions, especially the critical phase transition from water to ice. This sensitivity is the key to detecting ice formation at its onset, a critical requirement for aviation safety. The study concludes that graphene-based sensors tested under varied and controlled atmospheric conditions exhibit a remarkable potential to enhance ice detection systems for aircraft. Their lightweight, efficient, and highly responsive nature makes them a superior alternative to traditional ice detection technologies, paving the way for more advanced and reliable aircraft safety solutions.

7.
NPJ Microgravity ; 10(1): 16, 2024 Feb 10.
Article in English | MEDLINE | ID: mdl-38341423

ABSTRACT

Progress in mechanobiology allowed us to better understand the important role of mechanical forces in the regulation of biological processes. Space research in the field of life sciences clearly showed that gravity plays a crucial role in biological processes. The space environment offers the unique opportunity to carry out experiments without gravity, helping us not only to understand the effects of gravitational alterations on biological systems but also the mechanisms underlying mechanoperception and cell/tissue response to mechanical and gravitational stresses. Despite the progress made so far, for future space exploration programs it is necessary to increase our knowledge on the mechanotransduction processes as well as on the molecular mechanisms underlying microgravity-induced cell and tissue alterations. This white paper reports the suggestions and recommendations of the SciSpacE Science Community for the elaboration of the section of the European Space Agency roadmap "Biology in Space and Analogue Environments" focusing on "How are cells and tissues influenced by gravity and what are the gravity perception mechanisms?" The knowledge gaps that prevent the Science Community from fully answering this question and the activities proposed to fill them are discussed.

8.
Micromachines (Basel) ; 15(2)2024 Jan 28.
Article in English | MEDLINE | ID: mdl-38398926

ABSTRACT

This study details the development and validation of a graphene-based ice detection system, designed to enhance flight safety by monitoring ice accumulation on aircraft surfaces. The system employs a semiconductive polymer (PEDOT:PSS) with graphene electrodes, interpreting resistance changes to detect water impact and ice formation in real time. The sensor's performance was rigorously tested in a wind tunnel under various temperature and airflow conditions, focusing on resistance signal dependency on air temperature and phase change. The results demonstrate the sensor's ability to distinguish water droplet impacts from ice formation, with a notable correlation between resistance signal amplitude and water droplet impacts leading to ice accretion. Further analysis shows a significant relationship between air temperature and the resistance signal amplitude, particularly at lower temperatures beneficial to ice formation. This underlines the sensor's precision in varied atmospheric conditions. The system's compact design and accurate detection highlight its potential for improving aircraft ice monitoring, offering a path toward a robust and reliable ice detection system.

9.
NPJ Microgravity ; 9(1): 84, 2023 Oct 21.
Article in English | MEDLINE | ID: mdl-37865644

ABSTRACT

The present white paper concerns the indications and recommendations of the SciSpacE Science Community to make progress in filling the gaps of knowledge that prevent us from answering the question: "How Do Gravity Alterations Affect Animal and Human Systems at a Cellular/Tissue Level?" This is one of the five major scientific issues of the ESA roadmap "Biology in Space and Analogue Environments". Despite the many studies conducted so far on spaceflight adaptation mechanisms and related pathophysiological alterations observed in astronauts, we are not yet able to elaborate a synthetic integrated model of the many changes occurring at different system and functional levels. Consequently, it is difficult to develop credible models for predicting long-term consequences of human adaptation to the space environment, as well as to implement medical support plans for long-term missions and a strategy for preventing the possible health risks due to prolonged exposure to spaceflight beyond the low Earth orbit (LEO). The research activities suggested by the scientific community have the aim to overcome these problems by striving to connect biological and physiological aspects in a more holistic view of space adaptation effects.

10.
Materials (Basel) ; 16(17)2023 Aug 24.
Article in English | MEDLINE | ID: mdl-37687489

ABSTRACT

Recently, the goal of space exploration has shifted from the incognito of the solar system to the Moon. Concepts like human permanence on the Moon and thermal protective structures made with ISRU (in situ resource utilization) of raw materials have started to be implemented. By limiting the need to launch supplies from the Earth, the paradigm of spaceflight is changed, privileging the vanguard of the utilisation of resources in situ. Still, the main challenges of surviving the radiation dose and the cryogenic temperatures of the lunar night remain. Recent studies have demonstrated how innovative composite materials can help reduce the temperature stress on exploration vehicles. This research presents the material properties of aerogel insulating materials combined with LHS (lunar highlands simulant) regolith obtained by freeze frying. Organic-based aerogels with different percentages of LHS have been analysed in terms of material, morphology, and thermal properties.

11.
Spine J ; 23(12): 1920-1927, 2023 12.
Article in English | MEDLINE | ID: mdl-37572881

ABSTRACT

BACKGROUND CONTEXT: Intraoperative neuromonitoring (IONM) during surgical correction of spinal deformity has been shown to reduce iatrogenic injury in pediatric and adult populations. Although motor-evoked potentials (MEP), somatosensory-evoked potentials (SSEP), and electromyography (EMG) have been shown to be highly sensitive and specific in detecting spinal cord and nerve root injuries, their utility in detecting motor and sensory nerve root injury in pediatric high-grade spondylolisthesis (HGS) remains unknown. PURPOSE: We aim to assess the diagnostic accuracy and therapeutic impact of unimodal and multimodal IONM in the surgical management of HGS. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: Pediatric patients undergoing posterior spinal fusion (PSF) for treatment of HGS. OUTCOME MEASURES: Data on patient demographics, spinopelvic and spondylolisthesis parameters, and the presence of pre-and postoperative neurological deficits were collected. METHODS: Intraoperative MEP, SSEP, and EMG alerts were recorded. Alert criteria were defined as a change in amplitude of more than 50% for MEP and/or SSEP, with or without change in latency, and more than 10 seconds of sustained EMG activity. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated for each modality and the combination of MEP and SSEP. The 95% confidence intervals (CIs) were calculated using the exact (Clopper-Pearson) method. RESULTS: Fifty-four pediatric patients with HGS undergoing PSF between 2003 and 2021 in a single tertiary center were included. Seventy-two percent (39/54) of patients were female; the average age of patients was 13.7±2.3 years. The sensitivity of MEP in detecting new postoperative neurologic deficit was 92.3% (95% CI [64.0-99.8]), SSEP 77.8% (95% CI [40.0-97.2]), EMG 69.2% (95% CI [38.6-90.9]), and combination MEP and SSEP 100% (95% CI [73.5-100]). The specificity of MEP was 80.0% (95% CI [64.4-91.0]), SSEP 95.1% (95% CI [83.5-99.4]), EMG 65.9% (95% CI [49.4-79.9]), and combination MEP and SSEP 82.9% (95% CI [67.9-92.9]). The accuracy of SSEP was 92.0% (95% CI [80.8%-97.8%]), and the combination of MEP and SSEP was 86.8% (95% CI [74.7%-94.5%]). Twelve (22.2%) patients had a new motor or sensory deficit diagnosed immediately postoperatively. Nine patients made a full recovery, and 3 had some neurologic deficit on final follow-up. CONCLUSION: Unimodal IONM using SSEP and MEP alone were accurate in diagnosing sensory and motor nerve root injuries, respectively. The diagnostic accuracy in predicting motor and sensory nerve injuries in pediatric HGS improved further with the use of multimodal IONM (combining MEP and SEP). We recommend the utilization of multimodal IONM in all HGS PSF surgeries.


Subject(s)
Intraoperative Neurophysiological Monitoring , Peripheral Nerve Injuries , Radiculopathy , Spondylolisthesis , Adult , Humans , Child , Female , Adolescent , Male , Intraoperative Neurophysiological Monitoring/methods , Spondylolisthesis/diagnosis , Spondylolisthesis/surgery , Retrospective Studies , Evoked Potentials, Motor/physiology , Evoked Potentials, Somatosensory , Peripheral Nerve Injuries/diagnosis , Peripheral Nerve Injuries/etiology
12.
IEEE Trans Biomed Eng ; 70(10): 2886-2894, 2023 10.
Article in English | MEDLINE | ID: mdl-37067977

ABSTRACT

OBJECTIVE: An accurate and timely diagnosis of burn severity is critical to ensure a positive outcome. Laser Doppler imaging (LDI) has become a very useful tool for this task. It measures the perfusion of the burn and estimates its potential healing time. LDIs generate a 6-color palette image, with each color representing a healing time. This technique has very high costs associated. In resource-limited areas, such as low- and middle-income countries or remote locations like space, where access to specialized burn care is inadequate, more affordable and portable tools are required. This study proposes a novel image-to-image translation approach to estimate burn healing times, using a digital image to approximate the LDI. METHODS: This approach consists of a U-net architecture with a VGG-based encoder and applies the concept of ordinal classification. Paired digital and LDI images of burns were collected. The performance was evaluated with 10-fold cross-validation, mean absolute error (MAE), and color distribution differences between the ground truth and the estimated LDI. RESULTS: Results showed a satisfactory performance in terms of low MAE ( 0.2370 ±0.0086). However, the unbalanced distribution of colors in the data affects this performance. SIGNIFICANCE: This novel and unique approach serves as a basis for developing more accessible support tools in the burn care environment in resource-limited areas.


Subject(s)
Burns , Deep Learning , Humans , Skin , Laser-Doppler Flowmetry/methods , Wound Healing , Burns/diagnostic imaging , Burns/therapy
13.
Langmuir ; 39(1): 64-74, 2023 Jan 10.
Article in English | MEDLINE | ID: mdl-36575153

ABSTRACT

The shedding kinematics of water droplets in a condensation environment when exposed to aerodynamic forces in microgravity was studied. Understanding the shedding of droplets from a surface is a critical part of the dropwise condensation process for improving heat transfer. Because gravity as a droplet removal technique is not available in space, the use of airflow to shed droplets is considered for condensing heat exchangers in environmental control and life support systems. Surface coatings affect drop adhesion, and here, four different surfaces (PMMA, PS, PTFE, and SHS) and various droplet sizes (80, 60, and 40 µL) were used to understand the above phenomenon. It was found that the critical velocity to shed a droplet in microgravity was up to 8% lower than that in normal gravity. Also, the effect of the droplet size was investigated for both microgravity and normal gravity; the shedding velocity was lower for microgravity, and it decreased as droplet size increased. Increasing the hydrophobicity of the coating decreased the critical velocity for shedding. Finally, the droplet was found to detach from superhydrophobic surfaces in microgravity. The detachment of droplets from the substrate will hamper the condensation process that can produce a larger fresh area; also, detachment of droplets and entrainment in airflow counter the concept of removing moisture from the air in a dehumidification process.

14.
Sci Rep ; 12(1): 22107, 2022 Dec 21.
Article in English | MEDLINE | ID: mdl-36543823

ABSTRACT

A hydrogel film, poly-3,4-ethylenedioxythiophene (PEDOT):polystyrenesulfonate (PSS), containing an ionic liquid, is used as an air-cathode for a metal-air battery and its performance is investigated. This work presents the development of the air-cathode and the characterization of its physical, chemical and mechanical properties. Moreover, in view of wearable batteries, these air-cathodes are implemented within a flexible aluminium-air battery. It contains an aluminium anode, an electrolyte made of cellulose paper imbibed with an aqueous sodium chloride solution and the PEDOT:PSS air-cathode. Characterisation tests showed that the ionic liquid did not change the air-cathode chemically, while the electric conductivity increased considerably. The anode has an acceptable purity and was found to be resistant against self-corrosion. Discharge tests showed operating voltages up to 0.65 V, whereas two batteries in series could deliver up to 1.3 V at a current density of 0.9 mA cm-2 for almost a day, sufficient for monitoring and medical devices. Several discharge tests with current densities from 0.25 up to 2.5 mA cm-2 have presented operating lifetimes from 10 h up until over a day. At a current density of 2.8 mA cm-2, the operating voltage and lifetime dropped considerably, explained by approaching the limiting current density of about 3 mA cm-2, as evidenced by linear sweep voltammetry. The batteries showed high specific energies up to about 3140 Wh kg-1. Mechanical tests revealed a sufficient stretchability of the air-cathode, even after battery discharge, implying an acceptable degree of wearability. Together with the reusability of the air-cathode, the battery is a promising route towards a low-cost viable way for wearable power supply for monitoring medical devices with long lifetimes and high specific energies. Optimization of the air-cathode could even lead to higher power applications.

16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 459-462, 2022 07.
Article in English | MEDLINE | ID: mdl-36086430

ABSTRACT

The incidence of burn injuries is higher in low-and middle-income countries, and particularly in remote areas where the access to specialized burn assessment, care and recovery is limited. Given the high costs associated with one of the most used techniques to evaluate the severity of a burn, namely laser Doppler imaging (LDI), an alternative approach could be beneficial for remote locations. This study proposes a novel approach to estimate the LDI from digital images of a burn. The approach is a pixel-wise regression model based on convolutional neural networks. To minimize the dependency on the conditions in which the images are taken, the effect of two image normalization techniques is also studied. Results indicate that the model performs satisfactorily on average, presenting low mean absolute and squared errors and high structural similarity index. While no significant differences are found when changing the normalization of the images, the performance is affected by their quality. This suggests that changes in the intensity of the images do not alter the relevant information about the wound, whereas changes in brightness, contrast and sharpness do.


Subject(s)
Burns , Skin , Burns/diagnostic imaging , Diagnostic Imaging , Humans , Laser-Doppler Flowmetry/methods , Lasers
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 3915-3918, 2022 07.
Article in English | MEDLINE | ID: mdl-36086473

ABSTRACT

Scaffolds have been used to stimulate cell migration, cell adhesion, and cell proliferation as extracellular matrix analogues. This study proposes a novel method for creating hybrid alginate-gelatine aerogel-based scaffold, which could be suitable for cell adhesion. To this end, alginate-gelatine at 4% was first used to make stable hydrogels, which were then frozen at -70°C and dried under a vacuum to produced aerogels. Aerogels are materials known for their extremely low density, which, by definition, should be lower than 0.5 g/cm3, In this study, a bulk density of 0.16 g/cm3 was reached, confirming that the created material fits within the definition of an aerogel. In addition, the material presented a sponge-like structure, high absorption properties, and high-porosity, with an average pore size of 193µm. These properties fit within the requirements for fibroblast cell infiltrate and survival, demonstrating that the proposed alginate-gelatine aerogels are suitable candidates for various applications such as tissue engineering and regenerative medicine.


Subject(s)
Gelatin , Tissue Engineering , Alginates/chemistry , Gelatin/chemistry , Hydrogels , Tissue Engineering/methods , Tissue Scaffolds/chemistry
18.
Front Bioeng Biotechnol ; 10: 896166, 2022.
Article in English | MEDLINE | ID: mdl-35875487

ABSTRACT

Three-dimensional (3D) bio-printing has recently emerged as a crucial technology in tissue engineering, yet there are still challenges in selecting materials to obtain good print quality. Therefore, it is essential to study the influence of the chosen material (i.e., bio-ink) and the printing parameters on the final result. The "printability" of a bio-ink indicates its suitability for bio-printing. Hydrogels are a great choice because of their biocompatibility, but their printability is crucial for exploiting their properties and ensuring high printing accuracy. However, the printing settings are seldom addressed when printing hydrogels. In this context, this study explored the printability of double network (DN) hydrogels, from printing lines (1D structures) to lattices (2D structures) and 3D tubular structures, with a focus on printing accuracy. The DN hydrogel has two entangled cross-linked networks and a balanced mechanical performance combining high strength, toughness, and biocompatibility. The combination of poly (ethylene glycol)-diacrylate (PEDGA) and sodium alginate (SA) enables the qualities mentioned earlier to be met, as well as the use of UV to prevent filament collapse under gravity. Critical correlations between the printability and settings, such as velocity and viscosity of the ink, were identified. PEGDA/alginate-based double network hydrogels were explored and prepared, and printing conditions were improved to achieve 3D complex architectures, such as tubular structures. The DN solution ink was found to be unsuitable for extrudability; hence, glycerol was added to enhance the process. Different glycerol concentrations and flow rates were investigated. The solution containing 25% glycerol and a flow rate of 2 mm/s yielded the best printing accuracy. Thanks to these parameters, a line width of 1 mm and an angle printing inaccuracy of less than 1° were achieved, indicating good shape accuracy. Once the optimal parameters were identified, a tubular structure was achieved with a high printing accuracy. This study demonstrated a 3D printing hydrogel structure using a commercial 3D bio-printer (REGEMAT 3D BIO V1) by synchronizing all parameters, serving as a reference for future more complex 3D structures.

19.
Front Bioeng Biotechnol ; 10: 806362, 2022.
Article in English | MEDLINE | ID: mdl-35646874

ABSTRACT

Wound management in Space is an important factor to be considered in future Human Space Exploration. It demands the development of reliable wound monitoring systems that will facilitate the assessment and proper care of wounds in isolated environments, such as Space. One possible system could be developed using liquid crystal films, which have been a promising solution for real-time in-situ temperature monitoring in healthcare, but they are not yet implemented in clinical practice. To progress in the latter, the goal of this study is twofold. First, it provides a full characterization of a sensing element composed of thermotropic liquid crystals arrays embedded between two elastomer layers, and second, it discusses how such a system compares against non-local infrared measurements. The sensing element evaluated here has an operating temperature range of 34-38°C, and a quick response time of approximately 0.25 s. The temperature distribution of surfaces obtained using this system was compared to the one obtained using the infrared thermography, a technique commonly used to measure temperature distributions at the wound site. This comparison was done on a mimicked wound, and results indicate that the proposed sensing element can reproduce the temperature distributions, similar to the ones obtained using infrared imaging. Although there is a long way to go before implementing the liquid crystal sensing element into clinical practice, the results of this work demonstrate that such sensors can be suitable for future wound monitoring systems.

20.
Int J Spine Surg ; 16(1): 194-201, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35177526

ABSTRACT

BACKGROUND: Congenital kyphoscoliosis due to hemivertebra is generally treated surgically because of high risk of curve progression and high risk of nervous system complications. Modern posterior access surgical techniques, including total hemivertebra resection, can completely correct deformity without additional anterior access surgeries. The purpose of this study was to evaluate midterm results of hemivertebra resection and spinal arthrodesis; the hypothesis was that it is a safe, effective, and reproducible procedure. MATERIALS AND METHODS: From 2006 to 2019, hemivertebra resection and instrumented spinal arthrodesis with pedicle screws was performed on 82 patients with congenital vertebral deformities (62 scoliosis and 20 kyphoscoliosis) by posterior approach. Mean age at surgery was 8.6 years, and 22 patients were under 10 years of age. After stabilization patients have been braced for a period from 3 to 5 months. RESULTS: Mean follow-up was 9.6 years (range 1.2-12.8 years); mean kyphosis curve after surgery was reduced to 20° Cobb; and mean scoliosis curve was reduced to 11° Cobb. We experienced no major complications (postsurgical infection, instrumentation failure, severe neurological impairment, severe blood loss) at latest follow-up . CONCLUSION: We strongly advocate one-time posterior hemivertebra resection and arthrodesis as the most suitable surgical procedure for congenital scoliosis due to hemivertebra. Posterior approach interventions with pedicle screws instrumentation are less invasive than combined anterior-posterior approach interventions. We think that posterior approach procedures can lead to excellent deformity correction in both frontal and sagittal views, optimal stability, and low risk of nervous injury. CLINICAL RELEVANCE: Congenital scoliosis treatment is one of the most challeging conditions a spine surgeon has to face. We advocate that a one-stage posterior approach for hemivertebrectomy and fusion is a reliable, safe tachnique, whom excellent results remain stable at a mid/long-term follow-up. LEVEL OF EVIDENCE: Level 4.

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