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1.
Proc Biol Sci ; 291(2015): 20232196, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38290542

RESUMEN

The order Chiroptera (bats) is the second largest group of mammals. One of the essential adaptations that have allowed bats to dominate the night skies is laryngeal echolocation, where bats emit ultrasonic pulses and listen to the returned echo to produce high-resolution 'images' of their surroundings. There are two possible scenarios for the evolutionary origin of laryngeal echolocation in bats: (1) a single origin in a common ancestor followed by the secondary loss in Pteropodidae, or (2) two convergent origins in Rhinolophoidea and Yangochiroptera. Although data from palaeontological, anatomical, developmental and genomic studies of auditory apparatuses exist, they remain inconclusive concerning the evolutionary origin of bat laryngeal echolocation. Here we compared musculoskeletal morphogenesis of the larynx in several chiropteran lineages and found distinct laryngeal modifications in two echolocating lineages, rhinolophoids and yangochiropterans. Our findings support the second scenario that rhinolophoids and yangochiropterans convergently evolved advanced laryngeal echolocation through anatomical modifications of the larynx for ultrasonic sound generation and refinement of the auditory apparatuses for more detailed sound perception.


Asunto(s)
Quirópteros , Ecolocación , Laringe , Animales , Evolución Biológica , Filogenia , Quirópteros/genética
2.
Ann Bot ; 133(4): 605-620, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38362930

RESUMEN

BACKGROUND AND AIMS: Variation in architectural traits related to the spatial and angular distribution of leaf area can have considerable impacts on canopy-scale fluxes contributing to water-use efficiency (WUE). These architectural traits are frequent targets for crop improvement and for improving the understanding and predictions of net ecosystem carbon and water fluxes. METHODS: A three-dimensional, leaf-resolving model along with a range of virtually generated hypothetical canopies were used to quantify interactions between canopy structure and WUE by examining its response to variation of leaf inclination independent of leaf azimuth, canopy heterogeneity, vegetation density and physiological parameters. KEY RESULTS: Overall, increasing leaf area index (LAI), increasing the daily-averaged fraction of leaf area projected in the sun direction (Gavg) via the leaf inclination or azimuth distribution and increasing homogeneity had a similar effect on canopy-scale daily fluxes contributing to WUE. Increasing any of these parameters tended to increase daily light interception, increase daily net photosynthesis at low LAI and decrease it at high LAI, increase daily transpiration and decrease WUE. Isolated spherical crowns could decrease photosynthesis by ~60 % but increase daily WUE ≤130 % relative to a homogeneous canopy with equivalent leaf area density. There was no observed optimum in daily canopy WUE as LAI, leaf angle distribution or heterogeneity was varied. However, when the canopy was dense, a more vertical leaf angle distribution could increase both photosynthesis and WUE simultaneously. CONCLUSIONS: Variation in leaf angle and density distributions can have a substantial impact on canopy-level carbon and water fluxes, with potential trade-offs between the two. These traits might therefore be viable target traits for increasing or maintaining crop productivity while using less water, and for improvement of simplified models. Increasing canopy density or decreasing canopy heterogeneity increases the impact of leaf angle on WUE and its dependent processes.


Asunto(s)
Fotosíntesis , Hojas de la Planta , Agua , Hojas de la Planta/fisiología , Hojas de la Planta/anatomía & histología , Agua/metabolismo , Agua/fisiología , Fotosíntesis/fisiología , Transpiración de Plantas/fisiología , Modelos Biológicos , Ecosistema , Luz
3.
Annu Rev Clin Psychol ; 20(1): 431-455, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38211624

RESUMEN

The Alternative Model of Personality Disorders (AMPD) is a dimensional, empirically based diagnostic system developed to overcome the serious limitations of traditional categories. We review the mounting evidence on its convergent and discriminant validity, with an incursion into the less-studied ICD-11 system. In the literature, the AMPD's Pathological Trait Model (Criterion B) shows excellent convergence with normal personality traits, and it could be useful as an organizing framework for mental disorders. In contrast, Personality Functioning (Criterion A) cannot be distinguished from personality traits, lacks both discriminant and incremental validity, and has a shaky theoretical background. We offer some suggestions with a view to the future. These include removing Criterion A, using the real-life consequences of traits as indicators of severity, delving into the dynamic mechanisms underlying traits, and furthering the integration of currently disengaged psychological paradigms that can shape a sounder clinical science.


Asunto(s)
Modelos Psicológicos , Trastornos de la Personalidad , Humanos , Trastornos de la Personalidad/diagnóstico , Trastornos de la Personalidad/clasificación , Trastornos de la Personalidad/fisiopatología , Clasificación Internacional de Enfermedades , Reproducibilidad de los Resultados
4.
Pediatr Radiol ; 54(3): 450-456, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37039912

RESUMEN

Effective communication of imaging findings in term hypoxic ischemic injury to family members, non-radiologist colleagues and members of the legal profession can be extremely challenging through text-based radiology reports. Utilization of three-dimensional (D) printed models, where the actual findings of the brain can be communicated via tactile perception, is a potential solution which has not yet been tested in practice. We aimed to determine the sensitivity and specificity of different groups, comprising trained radiologists, non-radiologist physicians and non-physicians, in the detection of gross disease of the cerebral cortex from 3-D printed brain models derived from magnetic resonance imaging (MRI) scans of children. Ten MRI scans in children of varying ages with either watershed pattern hypoxic ischemic injury (cortical injury) or basal-ganglia-thalamus hypoxic ischemic injury pattern with limited perirolandic cortical abnormalities and 2 normal MRI scans were post processed and 3-D printed. In total, 71 participants reviewed the 12 models and were required to indicate only the brain models that they felt were abnormal (with a moderate to high degree of degree of confidence). The 71 participants included in the study were 38 laypeople (54%), 17 radiographic technologists (24%), 6 nurses (8%), 5 general radiologists (7%), 4 non-radiologist physicians- 3 pediatricians and 1 neurologist (6%) and 1 emergency medical services staff (1%). The sensitivity and specificity for detecting the abnormal brains of the 71 participants were calculated. Radiologists showed the highest sensitivity (72%) and specificity (70%). Non-radiologist physicians had a sensitivity of 67.5% and a specificity of 75%. Nurses had a sensitivity of 70% and a specificity of 41.7%. Laypeople (non-medical trained) had a sensitivity of 56.1% and a specificity of 55.3%. Radiologists' high sensitivity and specificity of 72% and 70%, respectively, validates the accuracy of the 3-D-printed models in reproducing abnormalities from MRI scans. The non-radiologist physicians also had a high sensitivity and specificity. Laypeople, without any prior training or guidance in looking at the models, had a sensitivity of 56.1% and a specificity of 55.3%. These results show the potential for use of the 3-D printed brains as an alternate form of communication for conveying the pathological findings of hypoxic ischemic injury of the brain to laypeople.


Asunto(s)
Hipoxia-Isquemia Encefálica , Niño , Humanos , Hipoxia-Isquemia Encefálica/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Encéfalo , Sensibilidad y Especificidad , Radiólogos
5.
Neurosurg Focus ; 56(1): E6, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38163339

RESUMEN

OBJECTIVE: A comprehensive understanding of microsurgical neuroanatomy, familiarity with the operating room environment, patient positioning in relation to the surgery, and knowledge of surgical approaches is crucial in neurosurgical education. However, challenges such as limited patient exposure, heightened patient safety concerns, a decreased availability of surgical cases during training, and difficulties in accessing cadavers and laboratories have adversely impacted this education. Three-dimensional (3D) models and augmented reality (AR) applications can be utilized to depict the cortical and white matter anatomy of the brain, create virtual models of patient surgical positions, and simulate the operating room and neuroanatomy laboratory environment. Herein, the authors, who used a single application, aimed to demonstrate the creation of 3D models of anatomical cadaver dissections, surgical approaches, patient surgical positions, and operating room and laboratory designs as alternative educational materials for neurosurgical training. METHODS: A 3D modeling application (Scaniverse) was employed to generate 3D models of cadaveric brain specimens and surgical approaches using photogrammetry. It was also used to create virtual representations of the operating room and laboratory environment, as well as the surgical positions of patients, by utilizing light detection and ranging (LiDAR) sensor technology for accurate spatial mapping. These virtual models were then presented in AR for educational purposes. RESULTS: Virtual representations in three dimensions were created to depict cadaver specimens, surgical approaches, patient surgical positions, and the operating room and laboratory environment. These models offer the flexibility of rotation and movement in various planes for improved visualization and understanding. The operating room and laboratory environment were rendered in three dimensions to create a simulation that could be navigated using AR and mixed reality technology. Realistic cadaveric models with intricate details were showcased on internet-based platforms and AR platforms for enhanced visualization and learning. CONCLUSIONS: The utilization of this cost-effective, straightforward, and readily available approach to generate 3D models has the potential to enhance neuroanatomical and neurosurgical education. These digital models can be easily stored and shared via the internet, making them accessible to neurosurgeons worldwide for educational purposes.


Asunto(s)
Neuroanatomía , Quirófanos , Humanos , Neuroanatomía/educación , Laboratorios , Simulación por Computador , Cadáver
6.
Sensors (Basel) ; 24(17)2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39275634

RESUMEN

As the Rural Revitalization Strategy continues to progress, there is an increasing demand for the digitization of rural houses, roads, and roadside trees. Given the characteristics of rural areas, such as narrow roads, high building density, and low-rise buildings, the precise and automated generation of outdoor floor plans and 3D models for rural areas is the core research issue of this paper. The specific research content is as follows: Using the point cloud data of the outer walls of rural houses collected by backpack LiDAR as the data source, this paper proposes an algorithm for drawing outdoor floor plans based on the topological relationship of sliced and rasterized wall point clouds. This algorithm aims to meet the needs of periodically updating large-scale rural house floor plans. By comparing the coordinates of house corner points measured with RTK, it is verified that the floor plans drawn by this algorithm can meet the accuracy requirements of 1:1000 topographic maps. Additionally, based on the generated outdoor floor plans, this paper proposes an algorithm for quickly generating outdoor 3D models of rural houses using the height information of wall point clouds. This algorithm can quickly generate outdoor 3D models of rural houses by longitudinally stretching the floor plans, meeting the requirements for 3D models in spatial analyses such as lighting and inundation. By measuring the distance from the wall point clouds to the 3D models and conducting statistical analysis, results show that the distances are concentrated between -0.1 m and 0.1 m. The 3D model generated by the method proposed in this paper can be used as one of the basic data for real 3D construction.

7.
Clin Anat ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38715464

RESUMEN

The dysplastic hip is characterized by incomplete coverage of the femoral head, resulting in increased risk of early osteoarthritis. The morphological variation of the hip joint is diverse and clear differences exist between females and males. The aim of this observational study was therefore to investigate the relationship between the morphology of the hip, sex, and hip dysplasia using a three-dimensional model. Statistical shape models of the combined femur and pelvic bones were created from bilateral hips of 75 patients. Using manual angle measurements and regression analysis, the characteristic shape differences associated with sex and hip dysplasia were determined. The model showed clear differences associated with sex and hip dysplasia. We found that the acetabular anteversion in females was significantly higher (p < 0.0001) than in males while no significant difference in acetabular anteversion was found between normal and dysplastic hips (p = 0.11). The model showed that decreased acetabular anteversion resulted in the appearance of the cross-over sign and the prominent ischial spine sign commonly associated with retroversion. Sex could be predicted with an area under the curve of 0.99 and hip dysplasia could be predicted with an area under the curve of ≥0.73. Our findings suggest that retroversion is a result of decreased anteversion of the acetabulum and is primarily associated with sex. This finding should be taken into account during the reorientation of the acetabulum in the surgical treatment of hip dysplasia.

8.
Medicina (Kaunas) ; 60(6)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38929603

RESUMEN

Background and Objectives: To assess femoral shaft bowing (FSB) in coronal and sagittal planes and introduce the clinical implications of total knee arthroplasty (TKA) by analyzing a three-dimensional (3D) model with virtual implantation of the femoral component. Materials and Methods: Sixty-eight patients (average age: 69.1 years) underwent 3D model reconstruction of medullary canals using computed tomography (CT) data imported into Mimics® software (version 21.0). A mechanical axis (MA) line was drawn from the midportion of the femoral head to the center of the intercondylar notch. Proximal/distal straight centerlines (length, 60 mm; diameter, 1 mm) were placed in the medullary canal's center. Acute angles between these centerlines were measured to assess lateral and anterior bowing. The acute angle between the distal centerline and MA line was measured for distal coronal and sagittal alignment in both anteroposterior (AP) and lateral views. The diameter of curve (DOC) along the posterior border of the medulla was measured. Results: The mean lateral bowing in the AP view was 3.71°, and the mean anterior bowing in the lateral view was 11.82°. The average DOC of the medullary canal was 1501.68 mm. The average distal coronal alignment of all femurs was 6.40°, while the distal sagittal alignment was 2.66°. Overall, 22 femurs had coronal bowing, 42 had sagittal bowing, and 15 had both. Conclusions: In Asian populations, FSB can occur in coronal, sagittal, or both planes. Increased anterolateral FSB may lead to cortical abutment in the sagittal plane, despite limited space in the coronal plane. During TKA, distal coronal alignment guides the distal femoral valgus cut angle, whereas distal sagittal alignment aids in predicting femoral component positioning to avoid anterior notching. However, osteotomies along the anterior cortical bone intended to prevent notching may result in outliers due to differences between the distal sagittal alignment and the distal anterior cortical axis.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Fémur , Imagenología Tridimensional , Tomografía Computarizada por Rayos X , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Anciano , Femenino , Masculino , Fémur/anatomía & histología , Fémur/diagnóstico por imagen , Fémur/cirugía , Imagenología Tridimensional/métodos , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Anciano de 80 o más Años
9.
Soins Psychiatr ; 45(350): 40-42, 2024.
Artículo en Francés | MEDLINE | ID: mdl-38218622

RESUMEN

The question of mental health can be approached using the three-dimensional model. In the light of the biological, environmental and circumstantial ingredients characterizing it, a critical analysis of both diagnosis and treatment can be proposed. The environment, like the individual, is both a factor and a player in psychological suffering. Treating one as well as the other is therefore the challenge of an ecosystemic approach.


Asunto(s)
Trastornos Mentales , Salud Mental , Humanos , Ecosistema , Trastornos Mentales/terapia , Ansiedad
10.
Biochem Biophys Res Commun ; 653: 69-75, 2023 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-36857902

RESUMEN

The medium-temperature alpha-amylase of Bacillus amyloliquefaciens is widely used in the food and washing process. Enhancing the thermostability of alpha-amylases and investigating the mechanism of stability are important for enzyme industry development. The optimal temperature and pH of the wild-type BAA and mutant MuBAA (D28E/V118A/S187D/K370 N) were all 60 °C and 6.0, respectively. The mutant MuBAA showed better thermostability at 50 °C and 60 °C, with a specific activity of 206.61 U/mg, which was 99.1% greater than that of the wild-type. By analyzing predicted structures, the improving thermostability of the mutant MuBAA was mainly related to enhanced stabilization of a loop region in domain B via more calcium-binding sites and intramolecular interactions around Asp187. Furthermore, additional intramolecular interactions around sites 28 and 370 in domain A were also beneficial for improving thermostability. Additionally, the decrease of steric hindrance at the active cavity increased the specific activity of the mutant MuBAA. Improving the thermostability of BAA has theoretical reference values for the modification of alpha-amylases.


Asunto(s)
Bacillus amyloliquefaciens , Bacillus , Bacillus amyloliquefaciens/genética , Bacillus amyloliquefaciens/metabolismo , Secuencia de Aminoácidos , alfa-Amilasas/genética , alfa-Amilasas/química , alfa-Amilasas/metabolismo , Estabilidad de Enzimas , Temperatura , Mutación
11.
Adv Exp Med Biol ; 1406: 79-102, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37016112

RESUMEN

Technology has revolutionized the way dentists are able to treat their patients. These technological advances have paved the way for the creation of virtual patient models utilizing these 3-dimensional intra-oral patient models, cone bean computer tomography (CBCT) radiograph scans, extraoral 3-dimensional scans, and jaw motion tracings to create a patient-specific model. These models are advantageous in planning surgical treatments by providing 3-dimensional views of vital anatomical structures to accurately identify the location, size, and shape of a structure or defect in order to plan accordingly. Virtual augmentation of either hard tissue (bone) and/or soft tissue (i.e., gingiva) can also be accomplished.Technology has allowed the capture of the dynamic motions of the jaw and combined them with the virtual patient to develop permanent restorations in harmony with the patient's orofacial complex. With the introduction of new technology in the realm of digital dentistry, patient care is being brought to a new and higher level. This creates a level of more optimal care that a dentist can deliver to patients.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Imagenología Tridimensional , Humanos , Imagenología Tridimensional/métodos , Tomografía Computarizada de Haz Cónico/métodos , Invenciones , Odontología
12.
Sensors (Basel) ; 23(24)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38139520

RESUMEN

The excretion care robot's (ECR) accurate recognition of transfer-assisted actions is crucial during its usage. However, transfer action recognition is a challenging task, especially since the differentiation of actions seriously affects its recognition speed, robustness, and generalization ability. We propose a novel approach for transfer action recognition assisted by a bidirectional long- and short-term memory (Bi-LSTM) network combined with a multi-head attention mechanism. Firstly, we utilize posture sensors to detect human movements and establish a lightweight three-dimensional (3D) model of the lower limbs. In particular, we adopt a discrete extended Kalman filter (DEKF) to improve the accuracy and foresight of pose solving. Then, we construct an action prediction model that incorporates a fused Bi-LSTM with Multi-head attention (MHA Bi-LSTM). The MHA extracts key information related to differentiated movements from different dimensions and assigns varying weights. Utilizing the Bi-LSTM network effectively combines past and future information to enhance the prediction results of differentiated actions. Finally, comparisons were made by three subjects in the proposed method and with two other time series based neural network models. The reliability of the MHA Bi-LSTM method was verified. These experimental results show that the introduced MHA Bi-LSTM model has a higher accuracy in predicting posture sensor-based excretory care actions. Our method provides a promising approach for handling transfer-assisted action individual differentiation in excretion care tasks.


Asunto(s)
Líquidos Corporales , Robótica , Humanos , Individualidad , Reproducibilidad de los Resultados , Extremidad Inferior
13.
J Clin Psychol ; 79(10): 2439-2451, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37310149

RESUMEN

OBJECTIVE: There is a strong evidence-base for a psychodynamic approach, supporting primary theoretical tenets as well as the treatment effectiveness. Additionally, there are increasing calls from the field for more individualized treatment for clients, and the lack of training in multiple orientations limits the ability of students in clinical psychology Ph.D. programs in the United States to personalize their treatments. The accumulated evidence-base for contemporary relational psychodynamic theory and therapy places it in good standing to return to the standard clinical psychology curriculum, along with other evidence-based approaches. METHODS: We use data from the Insider's Guide (which describes clinical Ph.D. programs in the United States) from three time points over 20 years to document the waning psychodynamic approach in clinical psychology programs. We review the scientific evidence for four primary tenets of a contemporary psychodynamic approach: three related to development-from healthy to psychopathological: (1) unconscious processes; (2) internal representations of self and other; (3) dimensional model of psychopathology, and a fourth tenet that builds on these three and is the foundation for a contemporary psychodynamic approach to psychotherapy: (4) therapeutic relationship as a primary mechanism of change. RESULTS/CONCLUSIONS: Based on the review of the evidence, we make specific recommendations for clinical psychology training programs about how to include a psychodynamic approach in the curriculum.


Asunto(s)
Psicología Clínica , Psicoterapia Psicodinámica , Humanos , Psicoterapia/métodos , Curriculum , Estudiantes , Resultado del Tratamiento , Psicoterapia Psicodinámica/métodos
14.
Entropy (Basel) ; 25(10)2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37895491

RESUMEN

Digital watermarking technology is an important means to effectively protect three-dimensional (3D) model data. Among them, "blind detection" and "robustness" are key and difficult points in the current research of digital watermarking technology based on 3D models. In order to realize the blind detection of a watermark and improve its robustness against various common attacks at the same time, this paper proposes a dual blind watermarking method based on the normal feature of the centroid of first-ring neighboring points. The local spherical coordinate system is constructed by calculating two different normal vectors, and the first pattern watermark and the second random binary sequence watermark are embedded, respectively. The experimental results show that this method can not only realize the blind detection of dual watermarks, but also have the ability to resist common attacks such as translation, rotation, scaling, cropping, simplification, smoothing, noise, and vertex reordering to a certain extent.

15.
Mol Microbiol ; 116(3): 890-908, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34184334

RESUMEN

The lipid mediators, platelet-activating factor (PAF) and lysophosphatidylcholine (LPC), play relevant pathophysiological roles in Trypanosoma cruzi infection. Several species of LPC, including C18:1 LPC, which mimics the effects of PAF, are synthesized by T. cruzi. The present study identified a receptor in T. cruzi, which was predicted to bind to PAF, and found it to be homologous to members of the progestin and adiponectin family of receptors (PAQRs). We constructed a three-dimensional model of the T. cruzi PAQR (TcPAQR) and performed molecular docking to predict the interactions of the TcPAQR model with C16:0 PAF and C18:1 LPC. We knocked out T. cruzi PAQR (TcPAQR) gene and confirmed the identity of the expressed protein through immunoblotting and immunofluorescence assays using an anti-human PAQR antibody. Wild-type and knockout (KO) parasites were also used to investigate the in vitro cell differentiation and interactions with peritoneal mouse macrophages; TcPAQR KO parasites were unable to react to C16:0 PAF or C18:1 LPC. Our data are highly suggestive that PAF and LPC act through TcPAQR in T. cruzi, triggering its cellular differentiation and ability to infect macrophages.


Asunto(s)
Lisofosfatidilcolinas/metabolismo , Factor de Activación Plaquetaria/metabolismo , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Trypanosoma cruzi/genética , Trypanosoma cruzi/metabolismo , Secuencia de Aminoácidos , Animales , Diferenciación Celular , Enfermedad de Chagas/parasitología , Técnicas de Inactivación de Genes/métodos , Interacciones Huésped-Parásitos , Humanos , Lisofosfatidilcolinas/química , Macrófagos , Ratones , Simulación del Acoplamiento Molecular , Filogenia , Factor de Activación Plaquetaria/química , Conformación Proteica , Proteínas Protozoarias/química , Receptores de Adiponectina/química , Receptores de Adiponectina/genética , Receptores de Adiponectina/metabolismo , Receptores de Progesterona/química , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Trypanosoma cruzi/química
16.
Microvasc Res ; 139: 104259, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34624307

RESUMEN

Blood flow pulsatility is an important determinant of macro- and microvascular physiology. Pulsatility is damped largely in the microcirculation, but the characteristics of this damping and the factors that regulate it have not been fully elucidated yet. Applying computational approaches to real microvascular network geometry, we examined the pattern of pulsatility damping and the role of potential damping factors, including pulse frequency, vascular viscous resistance, vascular compliance, viscoelastic behavior of the vessel wall, and wave propagation and reflection. To this end, three full rat mesenteric vascular networks were reconstructed from intravital microscopic recordings, a one-dimensional (1D) model was used to reproduce pulsatile properties within the network, and potential damping factors were examined by sensitivity analysis. Results demonstrate that blood flow pulsatility is predominantly damped at the arteriolar side and remains at a low level at the venular side. Damping was sensitive to pulse frequency, vascular viscous resistance and vascular compliance, whereas viscoelasticity of the vessel wall or wave propagation and reflection contributed little to pulsatility damping. The present results contribute to our understanding of mechanical forces and their regulation in the microcirculation.


Asunto(s)
Arteriolas/fisiología , Mesenterio/irrigación sanguínea , Microcirculación , Modelos Cardiovasculares , Flujo Pulsátil , Circulación Esplácnica , Vénulas/fisiología , Animales , Microscopía Intravital , Masculino , Ratas Wistar , Estrés Mecánico , Factores de Tiempo , Resistencia Vascular
17.
BMC Gastroenterol ; 22(1): 304, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35733109

RESUMEN

BACKGROUND: Distinguishing strangulated bowel obstruction (StBO) from simple bowel obstruction (SiBO) still poses a challenge for emergency surgeons. We aimed to construct a predictive model that could distinctly discriminate StBO from SiBO based on the degree of bowel ischemia. METHODS: The patients diagnosed with intestinal obstruction were enrolled and divided into SiBO group and StBO group. Binary logistic regression was applied to identify independent risk factors, and then predictive models based on radiological and multi-dimensional models were constructed. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were calculated to assess the accuracy of the predicted models. Via stratification analysis, we validated the multi-dimensional model in the prediction of transmural necrosis both in the training set and validation set. RESULTS: Of the 281 patients with SBO, 45 (16.0%) were found to have StBO, while 236(84.0%) with SiBO. The AUC of the radiological model was 0.706 (95%CI, 0.617-0.795). In the multivariate analysis, seven risk factors including pain duration ≤ 3 days (OR = 3.775), rebound tenderness (OR = 5.201), low-to-absent bowel sounds (OR = 5.006), low levels of potassium (OR = 3.696) and sodium (OR = 3.753), high levels of BUN (OR = 4.349), high radiological score (OR = 11.264) were identified. The AUC of the multi-dimensional model was 0.857(95%CI, 0.793-0.920). In the stratification analysis, the proportion of patients with transmural necrosis was significantly greater in the high-risk group (24%) than in the medium-risk group (3%). No transmural necrosis was found in the low-risk group. The AUC of the validation set was 0.910 (95%CI, 0.843-0.976). None of patients in the low-risk and medium-risk score group suffered with StBO. However, all patients with bowel ischemia (12%) and necrosis (24%) were resorted into high-risk score group. CONCLUSION: The novel multi-dimensional model offers a useful tool for predicting StBO. Clinical management could be performed according to the multivariate score.


Asunto(s)
Obstrucción Intestinal , Isquemia Mesentérica , Humanos , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/etiología , Intestino Delgado/diagnóstico por imagen , Isquemia , Necrosis , Estudios Retrospectivos
18.
Environ Sci Technol ; 56(24): 17712-17719, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36441951

RESUMEN

The mobility of nano zero-valent iron (nZVI) will greatly affect its practical application as a remediation material for contaminated groundwater. One-dimensional (1D) column tests are commonly used in previous work to study its migration behavior, but the two-dimensional (2D) test is still very limited. This study reports a novel research system to study the 2D transport and retention behavior of colloids and solutes, which includes a 2D model test setup and the corresponding image analysis method. The transport behaviors of methyl orange (MO), nZVI, and phosphate-loaded nZVI (PnZVI) are studied using this system. The results show that the research system can reasonably describe the tempo-spatial concentration distribution of colloids and solutes. After phosphate adsorption, the mobility of nZVI is enhanced due to the increase in negative surface charge, which implies a potential environmental risk of nZVI to facilitate contaminant transport. The migration of PnZVI is not significantly influenced by its density, which is faster than MO in the longitudinal direction. The range of the plume of PnZVI in the longitudinal direction is larger than that of MO, which implies that PnZVI has a stronger longitudinal dispersion than MO.

19.
Exp Lung Res ; 48(3): 126-136, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35594338

RESUMEN

Purpose: Idiopathic pulmonary fibrosis (IPF) is a complex progressive chronic lung disease where epithelial to mesenchymal interaction, extracellular matrix (ECM) contact, and pro-fibrotic cytokines dynamics take part in the development of the disease. The study of IPF in the widespread in vitro two-dimensional (2 D) culture fails to explain the interaction of cells with the changing environment that occurs in fibrotic lung tissue. A three-dimensional (3 D) co-culture model might shed light on the pathogenesis of IPF by mimicking the fibrotic environment. Materials and Methods: Fibroblasts from nine IPF were isolated and embedded in collagen matrices with the alveolar epithelial human cell line (A549) on the top. Cells were also cultured in 2 D with and without TGF-ß1 as a conventional model to compare with. Both types of cells were isolated separately. Protein and gene expression of the main fibrotic markers were measured by qPCR, Western blot, and ELISA. Results: IPF fibroblasts to myofibroblasts differentiation was observed in the 3 D model and in cells stimulated with TGF-ß1. In addition, ECM-related genes were highly up-regulated in the 3 D collagen matrix. A549 co-cultured 3 D with IPF fibroblasts showed EMT activation, with down-regulation of E-cadherin (CDH1). However, other pro-fibrotic genes as VIM, TGFB1, and MMP7 were up-regulated in A549 co-cultured 3 D with fibroblasts. Conclusions: 3 D-collagen matrices might induce fibroblasts' fibrotic phenotype as in the classic TGF-ß1 model, by up-regulating genes associated with matrix production. In addition, IPF lung fibroblasts seem to exert a pro-fibrotic influence in A549 cells when they are co-cultured. These results suggest that an improved 3 D co-culture model might serve as an important tool to study the fibrotic process and its regulation.


Asunto(s)
Fibrosis Pulmonar Idiopática , Factor de Crecimiento Transformador beta1 , Células Epiteliales Alveolares/metabolismo , Colágeno/metabolismo , Fibroblastos/metabolismo , Fibrosis , Humanos , Fibrosis Pulmonar Idiopática/genética , Pulmón/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo
20.
Indoor Air ; 32(6): e13066, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35762236

RESUMEN

Understanding airborne infectious disease transmission on public transport is essential to reducing the risk of infection of passengers and crew members. We propose a new one-dimensional (1D) model that predicts the longitudinal dispersion of airborne contaminants and the risk of disease transmission inside a railway carriage. We compare the results of this 1D-model to the predictions of a model that assumes the carriage is fully mixed. The 1D-model is validated using measurements of controlled carbon-dioxide experiments conducted in a full-scale railway carriage. We use our results to provide novel insights into the impact of various strategies to reduce the risk of airborne transmission on public transport.


Asunto(s)
Contaminación del Aire Interior , Contaminación del Aire Interior/análisis , Dióxido de Carbono
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