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Quality assessment of textile composites needs to have sufficient knowledge about the various types of non-destructive testing techniques to detect defects as well as the effect of these defects on mechanical performance. The paper aims to discuss these issues.

The major approach of this paper was to evaluate the potential of two inspection techniques named ultrasounds, vibrations for detecting textile reinforcement defects in composites and evaluate the composite performance in the presence of a damage.

Potential solutions have been identified to solve the issue of signal attenuation observed during C-scan ultrasonic testing, and the criticality of initial defects on static test was determined.

The research work presented here has been a first attempt to apply the combination of different techniques in particular polar scan for the textile composite inspection. This will become more crucial as requirements for high performance and complex shape textile composite parts.

The purpose of this paper is to experimentally investigate the capability of four non-destructive testing (NDT) techniques to detect the layer orientation in textile composite laminates. The aerospace industry has been the primary driving force in the use of textile composites.

Woven glass fiber composite samples were inspected using C-scan ultrasonic, vibration analyzer, X-ray micro-tomography and ultraviolet technique. In a complementary study, mechanical testing was carried out to investigate the effect of mid-layer orientation on in-plane tensile strength and their failure modes using microscopic imagining.

During C-scan ultrasonic, the high attenuation and scattering of ultrasonic waves caused by the textile fabric layers limited its application to only detect the first layer of samples. Frequency response tests of composite samples were also conducted to investigate the effect of mid-layer orientation on dynamic responses. The same trend was observed in the finite element modeling results with a clear effect of the fiber orientation defect seen in frequency response function response and higher mode shapes. Moreover, the results of micro computed tomography demonstrate that this technique could definitely detect the orientation of each layer; however, X-ray imaging at small scales introduced some challenges. Images obtained from ultraviolet technique did not reveal mid-layer orientation.

In this paper, the application of different NDT techniques along with finite element modeling to inspect two-dimensional textile composites was presented. Hopefully, the research results presented here will lead to much published papers in inspection of textile composites.

This study aims, a systematic review and meta-analysis, to evaluate the effects of folic acid (folate) on patients with depression.

Related articles were found by searching PubMed, SCOPUS, Web of science and Cochrane’s Library, from inception to January 2022. Weighted mean differences (WMD) were pooled using a random-effects model. Heterogeneity, sensitivity analysis and publication bias were reported using standard methods.

Pooled analysis of six randomized controlled trials revealed that folic acid supplementation decreased the depression score in the Beck Depression Inventory (WMD: −3.9; 95% CI: −5.3 to −2.4, p < 0.001) compared with control group, without heterogeneity (I2 = 0.0%, p = 1.000). It also lowered the depression score in the Hamilton (HAM) Depression Inventory (WMD: −3.5 mg/dL; 95% CI: −4.6 to −2.4, p < 0.001) compared with control group, with moderate heterogeneity (I2 = 71.8%, p = 0.007). Moreover, subgroup analysis showed that the folic acid supplementation reduced HAM in all subgroups. Meta-regression analysis demonstrated that there is no evidence of a significant linear relationship between dose and duration of folic acid supplementation and changes in HAM. Also, based on the non-linear dose response, no evidence of a relationship between dose and duration of folic acid supplementation and changes in HAM was found.

Folic acid supplementation could possibly have an effect on lowering depression in patients. However, the clinical trials thus far are insufficient for clinical guidelines and practice.