An evaluation of the morphological, microstructural and mechanical behaviour of the glass fibre/HDPE thermoplastic composite pipe.

Composite pipes are increasingly being used as an alternative solution to conventional metal-based pipes. This development is in response to significant corrosion failures with the metallic pipes and enables better decision making especially for the plausibility of alternative offshore energy sources. Flexible pipes which thermoplastic composite pipes (TCP) belong to have proven to have beneficial features. The aim of this research is to experimentally investigate TCP and the layers based on the morphological and mechanical properties, identify and utilize the methods to obtain relatively precise material properties of the TCP which are currently barely known

Advances in structural analysis and process monitoring of thermoplastic composite pipes.

Thermoplastic composite pipes (TCP) in comparison to other pipes have proven beneficial features due to its flexibility which includes being fit for purpose, lightweight and no corrosion. However, during the manufacturing of TCP which involves the consolidation process, certain defects may be induced in it because of certain parameters, and this can affect the performance of the pipe in the long run as the induced defects might lead to in-service defects. Current techniques used in the industry are facing challenges with on-the-spot detection in a continuous manufacturing system. In TCP manufacturing process, the pipe is regularly monitored. When a defect is noticed, the whole process stops, and the appropriate action is taken. However, shutting down the process is costly; hence it is vital to decrease the downtime during manufacturing to the barest minimum. The solutions include optimizing the process for reduction in the manufacturing defects amount and thoroughly understanding the effect of parameters which causes certain defect types in the pipe. This review covers the current state-of-the-art and challenges associated with characterizing the identified manufacturing induced defects in TCP. It discusses and describes all effective consolidation monitoring strategy for early detection of these defects during manufacturing through the application of suitable sensing technology that is compatible with the TCP. It can be deduced that there is a correlation between manufacturing process to the performance of the final part and selection of characterization technique as well as optimizing process parameters

Bio-based sustainable polymers and materials: from processing to biodegradation.

In the life cycle of a material, there will be either chemical or physical change due to varying environmental factors such as biological activity, light, heat, moisture, and chemical conditions. This process leads to polymer property change as pertains to functional deterioration because of the physical, biological, and chemical reactions that result in chemical transformations and bond scission and thus can be regarded as polymer degradation. Due to the present demand for sustainable polymers, bio-based polymers have been identified as a solution. There is therefore a need to compare the sustainability impacts of bio-based polymers, to maximize their use in functional use stage and still withhold the bio-degradation capability. This study focuses are poly (lactic acid) (PLA), Poly (ε-caprolactone) (PCL), polyhydroxyalkanoates (PHA), and polyamides (PA) as biopolymers of interest due to their potential in technological applications, stability, and biodegradability. For preparing bio-based value-added products, an appropriate selection of the fabrication or functional modification process is a very important factor for particular industrial or biomedical applications. The literature review indicates that in vivo is preferred to in vitro because it suits an overall study of the experiment's effects on a living subject. This study will explore these features in detail. In particular, the review will cover processing and biodegradation pathways for each of the biopolymers. In addition, thermal degredation and photodegradation are covered, and future trends and conclusions are drawn

3D printing for hip implant applications: a review.

There is a rising demand for replacement, regeneration of tissues and organ repairs for patients who suffer from diseased/damaged bones or tissues such as hip pains. The hip replacement treatment relies on the implant, which may not always meet the requirements due to mechanical and biocompatibility issues which in turn may aggravate the pain. To surpass these limitations, researchers are investigating the use of scaffolds as another approach for implants. Three-dimensional (3D) printing offers significant potential as an efficient fabrication technique on personalized organs as it is capable of biomimicking the intricate designs found in nature. In this review, the determining factors for hip replacement and the different fabrication techniques such as direct 3D printing, Fused Deposition Modelling (FDM), Selective Laser Sintering (SLS) and stereolithography (SLA) for hip replacement. The study also covers surface modifications of 3D printed implants and provides an overview on 3D tissue regeneration. To appreciate the current conventional hip replacement practices, the conventional metallic and ceramic materials are covered, highlighting their rationale as the material of choice. Next, the challenges, ethics and trends in the implants’ 3D printing are covered and conclusions drawn. The outlook and challenges are also presented here. The knowledge from this review indicates that 3D printing has enormous potential for providing a pathway for a sustainable hip replacement

Material challenges and opportunities in 3D printing for hip implant applications.

There is a current need for tissue and organ repairs, replacement and regeneration for the patients who suffer from diseased/damaged tissues or organs. This situation is continuously on the rise and the supply on this form of therapy does not meet the demand mostly due to lack of donors and biocompatibility issues which causes immune system rejection of the implants. To succeed through these limitations, researchers are currently carrying out investigation about the use of scaffolds as another approach for implants. The conventional scaffold fabrication technique is limited due to pore design accuracy. The 3D printing technology on the otherside can produce extracellular matrix with a higher degree of complexity and matching details such as pore size and geometry suitably based on certain factors including the tissue engineering, hip biomechanism, material suitability, ethical standards, future, and challenges. This paper in particular focus materials challenges and opportunities addressing various issues at various levels to materials-process-property relationship. It is comprehensive starting with hip biomechanism in gait and stress distribution to give the reader a clear perspective of the hip implants problem magnitude and details to consider when designing the materials. This is followed by 3D printing for orthopaedic applications and 3D hip tissue regeneration. The hip replacement materials including polymers, composites and metals are explored and corelated to conventional hip replacement materials. The work is concluded with some concluding remarks on opportunities, challenges, and future trends. The goal is to have scaffolds that have the capability of having a biomimicking design similar to the extracellular matrix with the advantage being the provision of structural supports for cell attachment, growth and differentiation with the main goal of producing an operational organ or tissue. The knowledge derived from this review offers huge potential for providing a pathway for sustainable healing

Manufacturing defects in thermoplastic composite pipes and their effect on the in-situ performance of thermoplastic composite pipes in oil and gas applications.

Thermoplastic composite pipes (TCP), which are a form of fibre reinforced thermoplastic pipes, have proven benefits such as being lightweight and non-corrosive. However, during manufacturing, certain defects are induced because of certain parameters, which eventually affect TCP performance in-service. Current manufacturing techniques are challenged with on-the-spot detection as the pipe is regularly monitored. When a defect is noticed, the process stops and action is taken. However, stopping the process is costly; hence it is vital to decrease downtime during manufacturing. Potential solutions are through process optimisation for defect reduction and an in-depth understanding of the effect of parameters that cause defect formation in the pipe. This article provides an overview of manufacturing influence on end performance. This is intimately linked to the material features, properties and performance in-service. The material features are the determinants for the manufacturing technique to be used. For TCP, it is a melt fusion bonding process involving heating and consolidation (other factors are consolidation speed and pull force). Thermal behaviour is essential at this phase as it determines the curing rate, hence it is deduced that laser heating is the better heat source in efficiency terms. Defects such as fibre misalignments, voids and delamination are induced here. The sources of these defects have been discussed herein as well as the secondary defects caused by them, with consideration of residual stress impact. The presence of manufacturing defects has been identified to influence performance in terms of strength and stiffness, interlaminar shear strength, toughness and creep. The next phase is to explore the state of the art in defect characterization during manufacturing for TCP. The in-situ characterization aims to derive high-quality TCP with reduced defects and need for repairs, and increased production rate in safe and eco-friendly conditions, while maintaining the current manufacturing process

Studies on the serological markers for hepatitis B virus infection among type 2 diabetic patients

Background: Hepatitis B infection is a public health concern globally. HBV can be as- sociated with type II diabetes mellitus, as HBV outbreaks have been observed among diabetics in healthcare facilities. This study evaluates the prevalence of HBV infec- tion among patients with type II diabetes mellitus. Method: A total of one hundred and eighty (180) diabetic patients and one-hundred non-diabetics (Controls) were recruited forthis study. Structured questionnaires were administered to the consented participants to obtain relevant data. Sera samples ob- tained were screened using the HBsAg ELISA kit; CTK Biotech, Inc, while the 5 panel kit—rapid diagnostic test, was used to assay for serological markers. Questionnaires were used to obtain relevant information and demographic data. Result: Overall prevalence of HBV infection among diabetes patients was 13.3%. Breakdown showed 9 (5.0%) seropositivity was obtained among male subjects com- pared to 15(8.3%) recorded among the females, P = .834; P < .05. Subjects aged 41-50 years recorded, 7(3.9%) positivity P = .774; P > .05. Educational status of par- ticipants showed 22 (12.2%) positivity among subjects with tertiary level of educa- tion P = .032; P < .05). Risk factors considered showed that 5(2.8%).seropositive subjects were alcoholic consumers (P value = .9711; P > .05). Result among non-di- abetics (Control) subjects showed (4%) seropositivity among the male subjects com- pared to (5.0%) seropositivity recorded among the female subjects (P = .739; P > .05). Conclusion: There is an indication of higher risk of HBV infection among type 2 dia- betic patients when compared to non-diabetics. There is the need for more research on this area of study, to further validate the association between HBV infection and Diabetes Mellitus

Intra-operative Diagnosis of Lower Segment Scar Dehiscence in a Second Gravida After One Previous Lower Segment Cesarean Section: Should We Advocate for Routine Antenatal Uterine Scar Thickness Testing?

Background: Uterine dehiscence is a separation of uterine musculature with intact uterine serosa. It can be encountered at the time of cesarean delivery, suspected on obstetric ultrasound or diagnosed in-between pregnancies. The antenatal diagnosis may occasionally elude the Obstetricians. This particular case demonstrates an intra-operative diagnosis of uterine dehiscence with missed antenatal ultrasound diagnosis in an asymptomatic woman. Case presentation: She was a 32-year-old Nigerian second gravida who booked for antenatal care at 32 weeks of gestation following a referral from her attending Obstetrician from a neighboring state due to relocation. She had 3 antenatal visits and 2 antenatal ultrasound investigations without uterine scar thickness report. She subsequently had elective Cesarean section (CS) at a gestational age of 38 weeks plus 2 days due to persistent breech presentation on a background of a previous lower segment CS scar. There was no previous uterine curettage prior to or after the previous lower segment CS scar and there was no labor pains prior to the elective CS. The surgery was successful with intra-operative findings of moderate intra parietal peritoneal adhesions with rectus sheath and obvious uterine dehiscence along the line of the previous CS scar. The fetal outcomes were normal. Immediate post-operative condition was satisfactory and the woman was discharged on a third-day post operation. Conclusion: Obstetricians are charged to maintain a high index of suspicion when managing pregnant women with history of emergency CS in order to avert the adverse consequences of uterine rupture from asymptomatic uterine dehiscence. Based on this report, it may be useful to routinely assess the lower uterine segment scar of women with previous emergency CS using the available ultrasound facilities. However, more studies are needed before advocating for routine antenatal uterine scar thickness testing following emergency lower segment CS in low and middle-income settings