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The application of pultruded glass fibre-reinforced polymer composites (PGFRPC) as a replacement material for conventional wooden cross-arm in high transmission towers is relatively new. Although there are several studies on enhancement of the cross-arm structure, there is still a lack of study on the elastic properties of a full-scale PGFRPC cross-arm enhanced with honeycomb sandwich structure. To full-fill the gap, this paper describes an experimental methodology used to obtain the elastic properties of the cross-arm using a three-point bending (3-PB) flexural test by following ASTM D790 standard for deflection behaviour and flexural creep response. The investigation involved several cross-arm members subjected to loading across different span lengths by propose two methods in order to measure the effective cross-arm member section flexural modulus (Ec) and shear modulus (Gc). The creep behaviour of the panels was successfully modeled using Findley's power law, confirming the ability of this empirical approach to simulate the viscoelastic response of the cross-arm. Next predictions were made for up to 50 years of service and the results shows the elastic modulus reduction for the enhanced cross-arm with the honeycomb sandwich structure was approximately reduce to 70 % compare with existing cross-arm which reduce almost 75 % at 50 years of application. The enhanced cross-arm exhibited lower deflection and better creep resistance and increased the bending strength of the cross-arm as well as extended its potential lifespan. Predictions indicated that the enhanced cross-arm maintained better mechanical properties over time compared to the existing one.

The utilization of pultruded glass fibre-reinforced polymer composites (PGFRPC) to replace traditional wooden cross-arms in high transmission towers is a relatively recent development. While there have been numerous investigations into enhancing cross-arm structures, there remains a notable absence of research focused on the elastic characteristics of a full-scale PGFRPC cross-arm, particularly one enhanced with a honeycomb sandwich structure. To full-fill the gap, this paper presents an experimental and numerical study through cantilever beam flexural tests on assembled cross-arm condition to examine deflection behavior and the flexural creep response. For deflection behavior, the load was applied up to actual working load. For creep behavior, the hanging load was applied for 1000 h in open area condition followed ASTM D2990 standards. By using Findley's power law, confirming the ability of this empirical approach to simulate the viscoelastic response of the cross-arm. The results obtained prove that the addition of a honeycomb sandwich structure reduced deflection and improved resilience against bending forces, enhancing specific points' elastic modulus slightly. Long-term creep tests revealed Point Y3 had the highest strain, but the enhanced cross-arm displayed superior resistance and a shorter viscoelastic transition period, indicating increased stability. Besides that, the Findley's Power Law Model effectively represented creep behavior for both cross-arm types, with low errors. Over 50 years, both versions showed a significant reduction in average elastic modulus, with the enhanced variant 20 % stronger due to the honeycomb structure. In conclusion, this study validates the superior creep properties of the enhanced PGFRPC cross-arm and demonstrates the honeycomb sandwich structure's substantial role in increasing strength and extending the cross-arm's lifespan, making it a valuable enhancement for such applications.

Owing to the high potential application need in the aerospace and structural industry for honeycomb sandwich composite, the study on the flexural behaviour of sandwich composite structure has attracted attention in recent decades. The excellent bending behaviour of sandwich composite structures is based on their facesheet (FS) and core materials. This research studied the effect of woven glass-fibre prepreg orientation on the honeycomb sandwich panel. A three-point bending flexural test was done as per ASTM C393 standard by applying a 5 kN load on different orientation angles of woven glass-fibre prepreg honeycomb sandwich panel: α = 0°, 45° and 90°. The results show that most of the sandwich panel has almost the same failure mode during the three-point bending test. Additionally, the α = 0° orientation angle shows a higher maximum load prior to the first failure occurrence compared to others due to higher flexibility but lower stiffness. In addition, the woven glass-fibre prepreg orientation angle, α = 0°, has the maximum stress and flexural modulus, which directly depend upon the maximum load value obtained during the flexural test. In addition, the experimental results and analytical prediction for honeycomb sandwich deflection show good agreement. According to the result obtained, it is revealed that woven glass-fibre honeycomb sandwich panels with an α = 0° orientation is a good alternative compared to 45° and 90°, especially when better bending application is the main purpose. The final result of this research can be applied to enhance the properties of glass-fibre-reinforced polymer composite (GFRPC) cross-arm and enhance the existing cross-arm used in high transmission towers.

Nowadays, pultruded glass fiber-reinforced polymer composite (PGFRPC) structures have been used widely for cross-arms in high transmission towers. These composite structures have replaced cross-arms of conventional materials like wood due to several factors, such as better strength, superior resistance to environmental degradation, reduced weight, and comparatively cheaper maintenance. However, lately, several performance failures have been found on existing cross-arm members, caused by moisture, temperature changes in the atmosphere, and other environmental factors, which may lead to a complete failure or reduced service life. As a potential solution for this problem, enhancing PGFRPC with honeycomb-filled composite structures will become a possible alternative that can sustain a longer service life compared to that of existing cross-arms. This is due to the new composite structures’ superior performance under mechanical duress in providing better stiffness, excellence in flexural characteristics, good energy absorption, and increased load-carrying capacity. Although there has been a lack of previous research done on the enhancement of existing composite cross-arms in applications for high transmission towers, several studies on the enhancement of hollow beams and tubes have been done. This paper provides a state-of-the-art review study on the mechanical efficiency of both PGFRPC structures and honeycomb-filled composite sandwich structures in experimental and analytical terms.

Purpose: Scholarly research is considered as a yardstick to measure progress and development in any country, institution, or subject or individual. This study describes the growth of publications in the field of dentistry by researchers affiliated to the Kingdom of Saudi Arabia (KSA) during two decades from 1998 to 2017. Research Design: This observational and quantitative analysis on dental research growth in KSA is based upon the data retrieved from Scopus database. This study was carried out at the College of Dentistry, King Saud bin Abdulaziz University for Health Sciences (KSAU-HS). Bibliometric indicators such as year-wise growth, productive author, research-type, source publication, productive national institutions, international research collaboration and collaborating countries have been used to illustrate research performance of KSA. Relevant bibliometric studies on medical and dental research have been reviewed. Microsoft Excel used for data analysis. Key Findings: The results of the study provide various characteristics of dental literature published during the projected period. Total of 6,415 research items produced by 22 Arab countries, a share of KSA counted 2,427 (37.83%) documents. Nearly half of the research items (n=1,209; 49.81%) published during the last three years from 2015 to 2017. Journal of Contemporary Dental Practice published 242 articles. King Saud University (KSU) appeared highest prolific national institution (n=938) and Alexandria University with 67 papers grasp top rank in international research collaborating institutions. United States (US) with 474 papers stood at the top in collaborating countries. Most of the papers have been written on the subject of dental procedures, resin, dental caries, tooth prosthesis and dental implants. Dr. Shankargouda Patil affiliated with Jazan University found as the most instrumental author with 60 publications in his credit. Conclusions/Implications: Findings of this study illustrate that dentistry has been progressing over the years in KSA. High tech dental research has a direct impact on the oral health and wellbeing of citizens. KSA researchers are thriving for more informed dental practices and research-based education leading to quality oral health care to their community. Keywords: dentistry; oral health research,Scholarly publication; bibliometric analysis; Saudi Arabia; Scopus; Biomedical publications, Introduction KSA is the largest country in the Arab world, investing sizeable amount on the provision of quality education and hi-tech health care facilities to its citizens. Numbers of higher [...]

Aim: This study was intended to investigate the marketing of library and information services in medical college libraries in the province of Punjab, Pakistan. Research Methodology: The study employed a descriptive survey research design. The population consisted of 55 medical library in-charges, irrespective of their administrative set-up (public and private). A self-administrated questionnaire comprising five-point Likert scale was prepared. Which was pilot-tested and revised. The questionnaire was used as an instrument for data collection consisted of seven main research questions with 72 items. The descriptive statistics, frequency, percentage, mean, and standard deviation of the data were analyzed by using IBM SPSS-23. Results: All the targeted respondents participated in the survey. Administratively, 18 medical colleges were functioning under the public sector domain, while 37 medical colleges were run by the private sector. The finding demonstrated the necessity of marketing library and information services in order fulfill the objectives of the library and inform patrons of the value of library use. Most of the medical libraries marketed themselves by providing valuable library services to their clientele. The competencies required for librarians in marketing library services are the ability to answer the user's query and evaluate, improve as well as introduce value-added services in the libraries. Furthermore, study's finding revealed that lack of funds, lack of the latest facilities to market library services and unsupportive attitude of administrations were the leading factors militating against marketing library services. Conclusion: Based on the findings it was concluded that more funds should be allocated, workshops and seminars should also be organized for librarians to train them on how to market their library services effectively. The curriculum of Library and Information Science/Information Management should be redesigned to accommodate marketing courses. Finally, librarians must be committed to improve their competencies and market their services in befitting manner. [ABSTRACT FROM AUTHOR]

Abstract Introduction Acute acalculous cholecystitis is traditionally associated with elderly or critically ill patients. Case presentation We present the case of an otherwise healthy 23-year-old Caucasian man who presented with acute right-sided abdominal pain. An ultrasound examination revealed evidence of acute acalculous cholecystitis. A laparoscopy was undertaken and the dual pathologies of acute acalculous cholecystitis and acute appendicitis were discovered and a laparoscopic cholecystectomy and appendectomy were performed. Conclusion Acute acalculous cholecystitis is a rare clinical entity in young, healthy patients and this report describes the unusual association of acute acalculous cholecystitis and appendicitis. A single stage combined laparoscopic appendectomy and cholecystectomy is an effective treatment modality.

Abstract Lipoid proteinosis is a rare autosomal recessive disease characterized by cutaneous and mucosal lesions and hoarseness appearing in early childhood that is caused by homozygous or compound heterozygous mutations in the ECM1 gene located on chromosome 1q21. The aim of the study was to investigate the molecular genetic defect underlying lipoid proteinosis in a consanguineous Pakistani family. Methods Genotyping of seven members of the family was performed by amplifying microsatellite markers, tightly linked to the ECM1 gene. To screen for mutations in the ECM1 gene, all of its exons and splice junctions were PCR amplified from genomic DNA and analyzed by SSCP and sequenced directly in an ABI 3130 genetic analyzer. Results The results revealed linkage of the LP family to the ECM1 locus. Sequence analysis of the coding exons and splice junctions of the ECM1 gene revealed a novel homozygous mutation (c.616C > T) in exon 6, predicted to replace glutamine with stop codon (p.Q206X) at amino acid position 206. Conclusions The finding of a novel mutation in Pakistani family extends the body of evidence that supports the importance of ECM1 gene for the development of lipoid proteinosis.

Background: Myasthenia gravis (MG) is an autoimmune disease affecting acetylcholine postsynaptic receptor of voluntary muscles. Thymectomy is done in these patients and is a mainstay in the treatment of MG; however, the long-term result of surgery is still controversial. This study dealt with the investigation of the results of thymectomy in treatment, recovery and control of the symptoms of these patients. Methods: This study was performed through a retrospective method in patients suffering from MG who underwent trans-sternal thymectomy between 2011 and 2016. We conducted thymectomy, excision of mediastinal mass and contents of tissues between the right and left phrenic nerves for all patients. Then, the effect of various variables including age, sex, time interval between onset of disease and surgery, thymus pathology and the dosage of drug on clinical response after surgery was determined using various statistical tests. Results: 47 patients including 26 men and 21 women with the mean age of 33.0 ± 4.6 years have been investigated. The mean age of patients was 36.2 and 29.7 in men and women respectively (P = 0.041). Spiral chest computed tomography (CT) scan was present in 47 patients demonstrating mediastinal mass in 40 (85.1%) patients. Also, our pathological results showed thymic cells in aortopulmonary window contents of 4 patients. According to the results, the younger age of patients at the time of surgery, shorter time between diagnosis and thymectomy, being a woman and non-thymoma pathology were along with better clinical outcomes after thymectomy. Conclusion: Our study shows better clinical results of thymectomy in patients with normal chest CT scan and normal or atrophic thymus in pathologic reports. Generally, it seems that performing thymectomy in a shorter time interval after diagnosis of MG is beneficial. Moreover, in MG patients who do not suffer from thymoma, it is along with positive results. [ABSTRACT FROM AUTHOR]

Pakistan is widely being portrayed a weak democratic state as elected governments were unnecessarily broken frequently. Violence in the recent years has given more strength to the negative perception of Pakistan as a polity not conducive for democratic institutions, this was doubled with the risk of military coup, which overshadowed the encouraging trends, like the maturing of Pakistani democracy, as demonstrated in parliament's adoption of far-reaching constitutional reforms. It is also evident that international community, at least indirectly if not directly, is the responsible for the lack of democracy and peace in Pakistan. Western powers, particularly, supported military government to promote their ideal of stability under misperceptions or for safeguarding of their own interests. [ABSTRACT FROM AUTHOR]

Junctional Epidermolysis Bullosa (JEB) affects intra-lamina lucida of skin and is an exclusively autosomal recessive mechanobullous disorder. Its major subtypes include Herlitz (H-JEB; MIM#226700) and non Herlitz-JEB (nH-JEB; MIM#226650). the former being the lethal form. Genetic causes of this disease include mutations in genes encoding for laminin-332 (LM-332) i.e. LA.1L43, LAMB3 and LAXÍC2. The objective of the current study was to elucidate the genetic basis of JEB patients in a consanguineous family of Pakistani origin. Screening of exons and intron-exon boundaries of LAMA3, LAMB3 and LAMC2 was carried out. Normal as well as carriers of the affected family, along with 99 healthy control individuals of the same ethnicity, were screened by PCR-RFLP and dye terminator cycle sequencing. Sequence analyses of the patient revealed homozygosity for a missense variant c.4540G>C (p.D1514H) in LAM43, which encodes the alpha chain of LM-332 (a skin adhesion protein) that is of importance for cell surface binding. The majority of cases with H-JEB are caused by truncating mutations with loss of LM-332 whereas missense mutations are extremely rare. These results add to the mutation spectrum associated with JEB and improve our understanding of LAXIA3 in epidermal-dermal integrity. [ABSTRACT FROM AUTHOR]

The article focuses on the use of a polytetrafluoroethylene (PTFE) vascular graft as an arterial and venous graft for kidney transplantations in several patients. The graft was interposed between the short renal vessels and the vessels of the recipients. It was used for making end-to-end and end-to-side anastomoses between the donor's renal artery and the external iliac artery of the recipient in case of two recipients. The graft was used for lengthening the veins and making end-to-end anastomoses between the renal veins and external iliac veins in three other recipients.

Competing Interests: Conflict of interests The authors declare no conflict of interest in this study.

Paraganglioma originates from chromaffin cells of adrenal medulla and autonomic paraganglia, which are derived from the neural crest cells. Paragangliomas are half as common as pheochromocytomas with 69% occurring in head and neck, 22% in abdomen and pelvis and 10% in the thorax. About 70% paragangliomas are sporadic, 30% are hereditary, having identifiable germline mutations of Succinate Dehydrogenase enzyme (SDH).