Fiber Architecture Research Articles

Supramolecular Conductive Hydrogels for Tissue Engineering Applications.

Owing to their unique attributes, including reversibility, specificity, directionality, and tunability, supramolecular biomaterials have evolved as an excellent alternative to conventional biomaterials like polymers, ceramics, and metals. Supramolecular hydrogels, in particular, have garnered significant interest because their fibrous architecture, high water content, and interconnected 3D network resemble the extracellular matrix to some extent. Consequently, supramolecular hydrogels have been used to develop biomaterials for tissue engineering. Supramolecular conductive hydrogels combine the advantages of supramolecular soft materials with the electrical properties of metals, making them highly relevant for electrogenic tissue engineering. Given the versatile applications of these hydrogels, it is essential to periodically review high-quality research in this area. In this review, we focus on recent advances in supramolecular conductive hydrogels, particularly their applications in tissue engineering. We discuss the conductive components of these hydrogels and highlight notable reports on their use in cardiac, skin, and neural tissue engineering. Additionally, we outline potential future developments in this field.

Progress in Multiscale Modeling of Silk Materials.

As a result of their hierarchical structure and biological processing, silk fibers rank among nature's most remarkable materials. The biocompatibility of silk-based materials and the exceptional mechanical properties of certain fibers has inspired the use of silk in numerous technical and medical applications. In recent years, computational modeling has clarified the relationship between the molecular architecture and emergent properties of silk fibers and has demonstrated predictive power in studies on novel biomaterials. Here, we review advances in modeling the structure and properties of natural and synthetic silk-based materials, from early structural studies of silkworm cocoon fibers to cutting-edge atomistic simulations of spider silk nanofibrils and the recent use of machine learning models. We explore applications of modeling across length scales: from quantum mechanical studies on model peptides, to atomistic and coarse-grained molecular dynamics simulations of silk proteins, to finite element analysis of spider webs. As computational power and algorithmic efficiency continue to advance, we expect multiscale modeling to become an indispensable tool for understanding nature's most impressive fibers and developing bioinspired functional materials.

Enhancement of pin‐bearing behavior of pultruded FRP profiles by multi‐directional fiber architecture design

AbstractThe low resistance of bolted joints in pultruded unidirectional (UD) fiber‐reinforced polymer (FRP) profiles limits the load grade of truss bridges due to shear damage along UD fibers. To address this issue, this study proposes multi‐directional (MD) fiber architecture in FRP profiles to improve the ultimate bearing strength of bolted joints. The digital image correlation shows that the addition of off‐axis fibers in MD FRP profiles prevents shear failure in the UD FRP profile. As a result, the ultimate bearing strengths of MD FRP profiles are enhanced attributed to “off‐axis fiber tie action”. Micro‐computed tomography shows that fiber damage in MD FRP profiles emerged from outer plies, including fiber breakage in 90° and ±45° fibers and fiber kinking in 0° and ±45° fibers. The off‐axis fibers break due to tension when resisting the bearing load in MD FRP profiles. The fiber kinking indicated strength contribution from 0° to ±45° fibers. The fiber breakage and fiber kinking in each ply are dominant in bearing failure instead of delamination, which increases the bearing strength of the pultruded MD FRP profiles. These findings facilitate controlling damage evolution in the pultruded MD FRP profiles and designing high‐resistance bolted joints.Highlights Multi‐directional fibers improved bearing strengths of FRP profiles by 28.5%–33%. Off‐axis fibers bent under pin‐bearing, forming a tie action until breakage. Fiber breakage and kinking in each ply contributed to the bearing failure. Strain localization and redistribution were observed using DIC.

Dynamic Compression of Glass/Epoxy Composites: The Effects of Fibre Architecture & Ageing, and Use of Energy Flux as a Characterisation Tool

Dynamic Compression of Glass/Epoxy Composites: The Effects of Fibre Architecture & Ageing, and Use of Energy Flux as a Characterisation Tool

Assessment of the supraspinatus muscle fiber architecture with diffusion tensor imaging in healthy volunteers

ObjectivesThis study presents a framework for the calculation of supraspinatus (SSP) muscle pennation angles (PAs) from diffusion tensor imaging (DTI).Materials and methodsTen healthy individuals (five females and five males; age 32.0 ± 4.7 years) underwent three sessions of 3-T MRI, including a stimulated echo acquisition mode DTI sequence. The imaging plane of the DTI sequence was angled along the intramuscular part of the SSP tendon. A custom-built software was developed and implemented to compute DTI-based PAs of the anterior and posterior SSP in relation to the orientation of the tendon. Subsequently, three readers measured PAs from the post-processed images. Test-retest reliability, inter-reader agreement, and intra-reader agreement of PA measurements were evaluated with intraclass correlation coefficients (ICCs).ResultsThe mean PA in the anterior SSP was 15.6 ± 2.1° and 10.7 ± 0.9° in the posterior SSP. MRI-derived PAs showed good to excellent test-retest reliability (ICC: 0.856–0.945), inter-reader agreement (ICC: 0.863–0.955), and intra-reader agreement (ICC: 0.804–0.955).ConclusionPAs derived from DTI demonstrated good to excellent test-retest reliability, inter-reader agreement, and intra-reader agreement. We successfully implemented a highly standardized technique for evaluating PAs of the SSP muscle.Critical relevance statementThis proposed low-complex method might facilitate the increased use of the PA as a biomarker for pathological conditions of the rotator cuff.Key PointsA low-complex method for measuring PAs of the SSP might help identify pathology early.The mean PA was 15.6 ± 2.1° and 10.7 ± 0.9° in the anterior and posterior SSP, respectively.ICCs were ≥ 0.856 for test-retest reliability, ≥ 0.863 for inter-reader agreement, and ≥ 0.804 for intra-reader agreement.Graphical

Bioinspired 4D Printed Tubular/Helicoidal Shape Changing Metacomposites for Programmable Structural Morphing

AbstractBiological structures combine passive shape‐changing with force generation through intricate composite architectures. Natural fibers, with their tubular‐like structures and responsive components, have inspired the design of pneumatic tubular soft composite actuators. However, no development of passive structural actuation is available despite the recent rise of 4D printing. In this study, a biomimicry approach is proposed with inspiration from natural fiber architecture to create a novel concept of thermally active 4D printed tubular metacomposites. These metacomposites exhibit high mechanical performance and 3D‐to‐3D shape‐changing ability triggered by changes in temperature. A rotative printer is proposed for winding a continuous carbon fibers reinforced PolyAmide 6.I composite on a PolyAmide 6.6 polymer mandrel in a similar manner to the structure of cellulose microfibrils within the polysaccharide matrix of natural fiber cell‐walls. The resulting 4D printed tubular metacomposites exhibit programmable rotation and torque in response to thermal variations thanks to the control of their mesostructure and the overall geometry. Energy density values representing a trade‐off between the rotation and the torque are comparable to shape memory alloys when normalized by stiffness. Finally, a proof of concept for an autonomous solar tracker is presented, showcasing its potential for designing autonomous assemblies for structure morphing.

Primary Breast Necrotising Fasciitis in an Elderly Woman Managed with Nipple–Areola Conservation and Delayed Primary Closure in a Resource-Poor Setting A Case Report

Abstract Primary breast necrotising fasciitis is a rare disease that can rapidly progress with high morbidity and mortality rates. Due to its rare occurrence, it is often misdiagnosed. This case was a 65-year-old, obese, immobile, and newly diagnosed woman who presented with a 2-week history of progressive left breast pain and swelling with associated darkening of the breast skin and discharge of foul-smelling fluid. There was no history of fever and the nipple–areola complex was spared. The surrounding healthy skin has a characteristic peau d’orange and erythematous. Two discrete and slightly tender left axillary lymph nodes were noted. At the presentation, her blood sugar was high. Initially, a breast malignancy was suspected but later an ultrasound showed increased fibrous and fatty tissue architecture of the mammary gland. It also noted inflammatory collections within the mammary glands and thus concluded breast inflammation. Early intervention with antibiotic cover and wound debridement forestalled the progress of the disease and nipple–areola salvage. The wound was later covered by delayed primary closure after 14 days of wound dressing with a silver-based solution. Breast asymmetry was noted as a surgical complication. Early aggressive intervention in necrotising fasciitis of the breast in an elderly woman with comorbidities contributed to the preservation of nipple–areola complex with eventual satisfactory management using direct wound closure.

Capturing sclera anisotropy using direct collagen fiber models. Linking microstructure to macroscopic mechanical properties.

Because of the crucial role of collagen fibers on soft tissue mechanics, there is great interest in techniques to incorporate them in computational models. Recently we introduced a direct fiber modeling approach for sclera based on representing the long-interwoven fibers. Our method differs from the conventional continuum approach to modeling sclera that homogenizes the fibers and describes them as statistical distributions for each element. At large scale our method captured gross collagen fiber bundle architecture from histology and experimental intraocular pressure-induced deformations. At small scale, a direct fiber model of a sclera sample reproduced equi-biaxial experimental behavior from the literature. In this study our goal was a much more challenging task for the direct fiber modeling: to capture specimen-specific 3D fiber architecture and anisotropic mechanics of four sclera samples tested under equibiaxial and four non-equibiaxial loadings. Samples of sclera from three eyes were isolated and tested in five biaxial loadings following an approach previously reported. Using microstructural architecture from polarized light microscopy we then created specimen-specific direct fiber models. Model fiber orientations agreed well with the histological information (adjusted R2's>0.89). Through an inverse-fitting process we determined model characteristics, including specimen-specific fiber mechanical properties to match equibiaxial loading. Interestingly, the equibiaxial properties also reproduced all the non-equibiaxial behaviors. These results indicate that the direct fiber modeling method naturally accounted for tissue anisotropy within its fiber structure. Direct fiber modeling is therefore a promising approach to understand how macroscopic behavior arises from microstructure.

Abstract A054: Collagen fiber architecture modulates PDAC cell and organoid phenotype

Abstract Introduction Collagen plays a significant role in the development of pancreatic ductal adenocarcinoma (PDAC). Disease progression is mediated by a dense collagenous stroma, which acts as a barrier to drug delivery and immune cell access. Current in vitro models do not well represent the collagenous stroma seen in PDAC. The aim of this study is to develop a fibrillar collagen-based hydrogel system which mimics the tumour microenvironment seen in PDAC and assess cell-mediated collagen remodeling. Methods Metastatic SUIT2-007 pancreatic cancer cells, non-metastatic BxPC3 pancreatic cancer cells, and human pancreatic stellate cells (hPSCs) were encapsulated in bovine type I collagen gels of various concentrations. KPC mouse derived tumour organoids were also encapsulated in bovine type I collagen gels of 2 mg/ml and 6 mg/ml concentrations, basement membrane extract (BME), and a combination of BME and collagen gel. Cell viability and proliferation was assessed using Live/Dead imaging and CellTitre-Glo 3D respectively. Cell mediated collagen remodeling was assessed via monitoring of gel contraction on the mm scale, and confocal reflectance microscopy on the cellular scale. Collagen contraction around cells was assessed by measuring the pixel intensity of collagen fibrils within the vicinity of the cell. Cell phenotype was assessed via immunofluorescent staining and qPCR. Results Collagen concentration alters the hydrogel structure and stiffness, with 3 mg/ml collagen resulting in straighter, shorter and thicker fibrils. Metastatic SUIT-007 cells contracted collagen gels more rapidly than non-metastatic BxPC3 cells, with both achieving similar contraction by day 7. SUIT2-007 cells remodel and align soft 1 mg/ml gels while 3 mg/ml gels proved to be sufficiently stiff to resist remodeling. Cellular collagen association was increased in more elongated SUIT-007 cells than in BxPC3 cells. Organoid proliferation varies with hydrogel collagen concentration. Conclusion Metastatic SUIT2-007 cells were able to remodel collagen more rapidly and to a greater extent than non-metastatic BxPC3 cells. Collagen supports an invasive organoid phenotype. Collagen gels combined with confocal reflectance microscopy provide a platform for the quantitative assessment of cell-matrix interactions in PDAC. Acknowledgements This project was funded by a Medical Traineeship from UCD School of Medicine, and summer student scholarships from Irish Cancer Society and Breakthrough Cancer Research. We acknowledge the Conway Imaging Core Facility for assistance with microscopy. Citation Format: Ciara L Doyle, Shanu Xavier, Jarren Y.S Lu, Leah Fallon, Anwesha Sarkar, Jan J Baguyo, Maela Gars, Stephen D Thorpe. Collagen fiber architecture modulates PDAC cell and organoid phenotype [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A054.

Multi-scale characterization of self-sensing fiber reinforced composites

The piezoresistive properties of fiber-based embedded sensors across tow, fabric, and laminate scales offer opportunities for their efficient application in fiber reinforced polymer composite (FRPC) structures. This study involves the multi-scale characterization of rGO-coated glass fiber tows, fabric, and laminates produced via vacuum assisted resin transfer molding (VARTM). The study demonstrates how fiber type, areal weight, and architecture affect piezoresistivity in rGO-coated glass fiber-based sensors subjected to in-plane tensile loading. In this study, rGO-coated glass fiber tows, with three linear densities (138, 1200, 1232 TEX), were examined. Fabric-level sensors, including plain weave (PW), and quadriaxial (QUAD), with areal densities of 200, 600, and 807 g/m2 were also studied. For comparison, laminates using UD carbon fabrics (300 g/m2) were employed as embedded piezoresistive sensors in the glass fiber-based laminates. It has been shown that rGO-coated sensors with lower areal weights outperformed all other sensor types in terms of their piezoresistive characteristics. This study suggests that piezoresistive sensors offer significant potential for use in load-bearing structural applications which can be further enhanced by investigating their lower scales.

Programming-via-spinning: Electrospun shape memory polymer fibers with simultaneous fabrication and programming

Porous shape memory polymer (SMP) scaffolds are promising ‘smart’ materials for potential use in a wide range of biomedical applications. Electrospinning provides an approach to produce fibrous SMP scaffolds to enhance their porosity, mass transfer, and flexibility. Here, we studied the effects of electrospinning parameters (rotating collector rotational speed and solvent) on shape memory and mechanical properties of a biostable thermoplastic polyurethane (PUr) SMP. Scanning electron microscopy confirmed that fiber diameter and tortuosity could be tuned using varied collector rotation speeds and/or solvents. Mechanical properties, including modulus, tensile strength, and ultimate elongation, were tuned independently of chemistry based on variations in fiber architectures. All scaffolds demonstrated shape memory properties. Additionally, due to strains that are trapped in the fibers during the electrospinning process, SMP fibers are programmed into a strained, temporary shape during the fabrication step. These fibers can be immediately triggered to recover to a non-strained primary shape after fabrication to reduce sample preparation time and complexity. As a proof-of-concept, bacterial protease-responsive SMPs were electrospun and exposed to S. aureus in programmed secondary shapes. Upon exposure to bacteria, these SMPs underwent shape recovery, which resulted in reduced bacterial attachment and biofilm formation. These materials could be employed as bacteria-responsive wound dressings in future work. Overall, electrospinning provides a valuable tool for tuning mechanical and shape memory properties independently from chemistry and for programming SMPs during fabrication to enable scale-up of electrospun SMP scaffolds.

Strain-dependent dynamic re-alignment of collagen fibers in skeletal muscle extracellular matrix

Collagen fiber architecture within the skeletal muscle extracellular matrix (ECM) is significant to passive muscle mechanics. While it is thought that collagen fibers re-orient themselves in response to changes in muscle length, this has not been dynamically visualized and quantified within a muscle. The goal of this study was to measure changes in collagen alignment across a range of muscle lengths and compare the corresponding alignment to muscle mechanics. We hypothesized that collagen fibers dynamically increase alignment in response to muscle stretching, and this change in alignment is related to passive muscle stiffness. Further, we hypothesized that digesting collagen fibers with collagenase would reduce the re-alignment response to muscle stretching. Using DBA/2J and D2.mdx mice, we isolated extensor digitorum longus (EDL), soleus, and diaphragm muscles for collagenase or sham treatment and decellularization to isolate intact or collagenase-digested decellularized muscles (DCMs). These DCMs were mechanically tested and imaged using second harmonic generation microscopy to measure collagen alignment across a range of strains. We found that collagen alignment increased in a strain-dependent fashion, but collagenase did not significantly affect the strain-dependent change in alignment. We also saw that the collagen fibers in the diaphragm epimysium (surface ECM) and perimysium (deep ECM) started at different angles, but still re-oriented in the same direction in response to stretching. These robust changes in collagen alignment were weakly related to passive DCM stiffness. Overall, we demonstrated that the architecture of muscle ECM is dynamic in response to strain and is related to passive muscle mechanics. Statement of significanceOur study presents a unique visualization and quantification of strain-induced changes in muscle collagen fiber alignment as they relate to passive mechanics. Using dynamic imaging of collagen in skeletal muscle we demonstrate that as skeletal muscle is stretched, collagen fibers re-orient themselves along the axis of stretch and increase their alignment. The degree of alignment and the increase in alignment are each weakly related to passive muscle stiffness. Collagenase treatments further demonstrate that the basis for muscle Extracellular matrix stiffness is dependent on factors beyond collagen crosslinking and alignment. Together the study contributes to the knowledge of the structure-function relationships of muscle extracellular matrix to tissue stiffness relevant to conditions of fibrosis and aberrant stiffness.

Soft Fibrous Syringe Architecture for Electricity-Free and Motorless Control of Flexible Robotic Systems.

Flexible robotic systems (FRSs) and wearable user interfaces (WUIs) have been widely used in medical fields, offering lower infection risk and shorter recovery, and supporting amiable human-machine interactions (HMIs). Recently, soft electric, thermal, magnetic, and fluidic actuators with enhanced safety and compliance have innovatively boosted the use of FRSs and WUIs across many sectors. Among them, soft hydraulic actuators offer great speed, low noise, and high force density. However, they currently require bulky electric motors/pumps, pistons, valves, rigid accessories, and complex controllers, which inherently result in high cost, low adaptation, and complex setups. This paper introduces a novel soft fibrous syringe architecture (SFSA) consisting of two or more hydraulically connected soft artificial muscles that enable electricity-free actuation, motorless control, and built-in sensing ability for use in FRSs and WUIs. Its capabilities are experimentally demonstrated with various robotic applications including teleoperated flexible catheters, cable-driven continuum robotic arms, and WUIs. In addition, its sensing abilities to detect passive and active touch, surface texture, and object stiffness are also proven. These excellent results demonstrate a high feasibility of using a current-free and motor-less control approach for the FRSs and WUIs, enabling new methods of sensing and actuation across the robotic field.

Embedded three-dimensional printing of thick pea-protein-enriched constructs for large, customized structured cell-based meat production

Recent 3D-printing research showed the potential of using plant-protein-enriched inks to fabricate cultivated meat (CM) via agar-based support baths. However, for fabricating large, customized, structured, thick cellular constructs and further cultivation, improved 3D-printing capabilities and diffusion limit circumvention are warranted. The presented study harnesses advanced printing and thick tissue engineering concepts for such purpose. By improving bath composition and altering printing design and execution, large-scale, marbled, 0.5-cm-thick rib-eye shaped constructs were obtained. The constructs featured stable fibrous architectures comparable to those of structured-meat products. Customized multi-cellular constructs with distinct regions were produced as well. Furthermore, sustainable 1-cm-thick cellular constructs were carefully designed and produced, which successfully maintained cell viability and activity for 3 weeks, through the combined effects of void-incorporation and dynamic culturing. As large, geometrically complex construct fabrication suitable for long-term cellular cultivation was demonstrated, these findings hold great promise for advancing structured CM research.

The formation mechanism of gradient properties and the regulation mechanism of elastic properties in three‐dimensional tubular braided composites

AbstractThree‐dimensional tubular braided composites (3DTBCs) have mitigated delamination issues typical of laminated composites, gaining wide industrial application. However, their intricate internal fiber architecture, influenced by processing techniques, leads to continuous property variations, resulting in localized stress concentrations that can cause premature component failure and significantly impact performance. This paper introduces a field theory‐based quantitative analysis method for property gradients and investigates their formation mechanism. Additionally, it explores the effects of braiding parameters on property gradients. The described analysis method enables the prediction of gradient structures and associated strength distributions, offering potential pathways for maximizing the strength of 3DTBC.Highlights The mesostructure and mechanical properties of three‐dimensional braided tubular composites inherently exhibit unavoidable gradient distributions. The performance gradient can be quantitatively described using field theory‐based analytical methods. The motion trajectory of the yarn carrier is the primary cause of the property gradient. The property gradient can be controlled by adjusting the braiding process parameters.

Muticomponent Melt‐Electrowritten Vascular Graft to Mimic and Guide Regeneration of Small Diameter Blood Vessels

AbstractCardiovascular disease is a leading cause of morbidity. Current treatments include vessel substitution using autologous/synthetic vascular grafts, but these commonly fail in small diameter applications, largely due to compliance mismatch and clot formation. In this study, a multicomponent vascular graft, that takes inspiration from native vessel architecture, is developed to overcome these limitations. Melt electrowriting (MEW) is used to produce tubular scaffolds with vascular‐mimetic fiber architecture and mechanics, which is combined with a lyophilized fibrinogen matrix with tailored degradation kinetics to generate a hybrid graft. The MEW framework not only contributes to graft mechanics, but also provides contact guidance to direct cell/neotissue orientation and mimic the native tunica media. This construct is further functionalized with heparin, which in combination with the smooth extracellular matrix (ECM) surface, reduced platelet adhesion and clot formation providing a substrate for endothelization, thereby mimicking the function of the intima. Lastly, an outer electrospun layer representing the adventitia is added to improve elasticity and reduce permeability. This graft satisfies ISO implantability requirements, matches the compliance of native vessels, and reestablishes physiological flow with minimal clot formation in a preclinical model. Therefore, this graft represents an innovative off‐the‐shelf alternative to address the unmet clinical need for small‐diameter vascular grafts.

Ultra-broad sensing range, high sensitivity textile pressure sensors with heterogeneous fibre architecture and molecular interconnection strategy

Textile-based pressure sensors have garnered extensive attentions owing to their potentials in health monitoring, human–machine interactions, wearable human–machine interfaces (HMIs) and soft robotics. High sensitivity over a broad sensing range are highly desired yet challenging for textile pressure sensors due to the incompressibility of matrix materials and the stiffening of microstructures. Herein, we developed a high performance pressure sensor based on the silk/3-Aminopropyltriethoxy-silane/titanium carbide (Silk/APTES/MXene) film. The silk is designed with heterogeneous fiber architecture, which enables rich and multi-level contact pattern and could compensate for the effect of structural stiffening. Furthermore, APTES molecules are used to enhance the interface bonding between MXene and silk, promoting the mechanical stability of the sensor. Benefiting from these advantages, the Silk/APTES/MXene sensor device is achieved with high sensitivity of 17.1 KPa−1 over an ultra-broad sensing range up to 3.3 MPa (R2 = 0.997), ultra-low detection limit (0.25 Pa), and low fatigue toughness after 5000 cycles loading and unloading. With these merits, we have demonstrated its capability for a series of human motion detection (such as foot movement detection, arm/wrist/finger bending, etc) and an overall accuracy of 95 % is obtained with the help of CNN-based convolution neural architecture. More significantly, we have built an entire intelligent human–machine dialogue system and a patient-audience dialogue system, from lip/sign language recognition to real-time screen display and final voice output.

Modeling of multi-kW in-band pumped triple-clad thulium-doped fiber architecture

We present a model and design for a high-power triple-clad thulium doped fiber specifically for in-band or tandem pumping. This fiber is designed to maximize the output signal power while taking into consideration common effects that limit high-power operation. In-band pumping will allow for thulium fiber lasers to reach multi-kW power levels.

Processing and properties of 3D woven SiC/SiC composites with hybrid matrix

3D woven SiC/SiC composites with Sylramic™-iBN SiC fibers have been fabricated by first partially infiltrating 3D woven fiber preforms with SiC by chemical vapor infiltration (CVI) and then by polymer infiltration and pyrolysis (PIP) of SiC-yielding polymer. The influence of fiber architecture on damage evolution and failure mechanisms during tensile loading, in-plane tensile properties, transverse thermal conductivity, and interlaminar tensile strength of the composites has been investigated. Wherever possible, the data are compared with those of 2D woven melt infiltrated (MI), CVI, and (CVI+PIP) hybrid SiC/SiC composites. The composites exhibit 300-hr creep durability at 1482 °C in air at stresses up to 138 MPa and show potential for elevated-temperature applications. Further improvements in composite properties are possible by optimizing composite constituents and fiber architecture.

Influence of Fibre Architectures on the Mechanical Properties and Damage Failures of Composite Laminates

Influence of Fibre Architectures on the Mechanical Properties and Damage Failures of Composite Laminates