Range Extension of \u3ci\u3eStylogomphus Albistylus\u3c/i\u3e (Odonata: Gomphidae) for the Upper Peninsula of Michigan

Larvae, exuviae, and teneral adults of Stylogomphus albistylus (Hagen) were collected from Mountain Stream, within the boundaries of the Huron Mountain Club, in the Upper Peninsula of Michigan (Marquette County). This represents the first published report of this species from the Upper Peninsula of Michigan, and only the second recorded site for the state of Michigan

Dissolution and diffusion characteristics of 316L stainless steel in molten zinc containing variable concentrations of aluminum

Molten metal corrosion of pot hardware materials in continuous galvanizing lines is an important factor in maintaining high productivity at steel sheet mills around the world. A complete understanding of the mechanisms which impact the corrosion properties of structural metals submerged in industrial molten zinc baths has not been achieved. Acquisition of deeper knowledge in this field is very difficult because of the numerous variables involved with the zinc environment. As an example, the aluminum content that is employed varies from near 0% aluminum in general (batch) galvanizing pots to around 0.14wt% Al for high-grade automotive sheet steels and again to aluminum levels exceeding 0.2wt% for various construction-grade steels. Moreover, it is widely experienced that the molten metal corrosivity of these small changes in aluminum concentration can have a pronounced impact on the life of submerged galvanizing hardware.;One aspect of understanding the molten zinc corrosion characteristics is determining the solubility of structural hardware metals as a function of changes in aluminum content in the liquid zinc. Hence, an array of tests was performed to measure the actual corrosion loss of 316L stainless steel samples after immersion in molten zinc with aluminum concentrations ranging from about 0% to 1wt% Al. In general, these tests indicated that the corrosion rate of 316L was quite high for pure zinc (0% Al) then decreased drastically at increasing aluminum levels between 0% and about 0.14wt% to a rather minimal corrosion rate beyond 0.14% aluminum, maintaining a low dissolution rate beyond 1% Al. The significance of 0.14wt% Al has been defined by not only the microanalysis of the reaction mechanisms on test samples but also by industry-accepted phase diagrams and previously published research.;Based on the results and procedures characterized by this investigation, it may be possible to further understand the reaction mechanisms and detailed corrosion features of other alloys utilized in industrial galvanizing operations, such as cobalt-based and iron-based superalloys. Furthermore, recognizing the significance of the phase transformations in the region of 0.14wt% aluminum on these advanced alloys may promote more focused research in this economically important aluminum regime

Effect of Social Media on Perceived Students Academic Performance of Higher Institutions: A case of Public Universities in Accra, Ghana

It is an undisputable fact that the advancement of technology has taken over all activities in the world. Being it business, education or church activities. The popularity of social media is relatively recent and the effect of Online Social Networking (OSN) on students’ performance has not received much scholarly attention. The aim of this study is to examine the role of social media on perceived students’ academic performance of higher educational institutions focusing on public universities in Accra, Ghana. The study adopted a descriptive survey. Purposive sampling technique was used to select three public universities within greater Accra Region. Primary data was collected using structured questionnaires which were administered personally. Stratified random sampling technique was used to select the sample size of 298 students from the three public universities. Data was presented by the use of frequency tables then analyzed using descriptive statistical techniques such as frequencies and percentages. A multiple regression analysis was also conducted to investigate the effect of social media platforms on students’ academic performance. The study ascertained that there is positive correlation between social media and academic performance and social media can be used to predict academic performance of tertiary students. The study concludes that most of the students use social media platforms to entertain themselves during lecture period when lectures is boring. It’s recommended that, tertiary institutions should make it a point connecting academic activities with social media platforms in order to get the attention of students to improve upon their academic performance. Keywords: Social Media, Perceived Students, Academic Performance and Public Universities in Ghan

Novel Oral Anticoagulants: A Comparative Study of the Clinical Potential for Dabigatran, Rivaroxaban, and Apixaban versus Warfarin

Although Coumadin® (warfarin) has been the standard outpatient anticoagulant for long-term prevention of thrombosis for many decades, it presents with significant challenges for both patients and health care providers in optimizing standards of care including dietary and drug restrictions, regular monitoring of the patient\u27s International Normalized Ratio (INR), and difficulty maintaining therapeutic levels. Despite its unmistakable effectiveness, there has been an interest from the medical community in developing potential alternative drug therapies. As a result, within the past three years the U.S. Food and Drug Administration (FDA) has approved the use of three new oral anticoagulant drugs (dabigatran, rivaroxaban, and apixaban) specifically targeting thrombin or factor Xa that have overcome many of the barriers seen in warfarin therapy. The use of these new oral anticoagulants is of particular interest in patients who have failed warfarin therapy or for whom warfarin therapy is contraindicated, in situations when monitoring is not feasible or interactions are problematic, or if patient INR control is poor. All of these novel agents are currently approved for prevention of thrombosis in patients with nonvalvular atrial fibrillation, and with ongoing clinical research these agents may present health care providers with additional therapeutic options in a greater variety of disease states. For the comparative purposes of this article, we have combined all of the recent clinical evidence and major landmark trials for each of these new agents as well as benefits and drawbacks of therapy in specific patient populations when compared to warfarin

Pitting and Repair of the Space Shuttle's Inconel(Registered TradeMark) Honeycomb Conical Seal Panel

During return to flight servicing of the rudder speed brake (RSB) for each Space Shuttle Orbiter, inspectors discovered numerous small pits on the surface of the #4 right hand side honeycomb panel that covers the rudder speed brake actuators. Shortly after detection of the problem, concurrent investigations were initiated to determine the extent of damage, the root cause, and to develop a repair plan, since fabrication of a replacement panel is impractical for cost, schedule, and sourcing considerations. This paper describes the approach, findings, conclusions and recommendations associated with the investigation of the conical seal pitting. It documents the cause and contributing factors of the pitting, the means used to isolate each contributor, and the supporting evidence for the primary cause of the pitting. Finally, the selection, development and verification of the repair procedure used to restore the conical seal panel is described with supporting process and metallurgical rationale for selection

Antibacterial Activity of Alchornea cordifolia (Christmas bush) Leaves Extract on Carbapenem Resistant Enterobacteriaceae Causing Multi-drug Resistant Systemic Infections

Carbapenems have been used for the treatment of systemic infections caused by Enterobacteriaceae. However, recent studies suggested that some Enterobacteriaceae are producing carbapenemases, which has limited the treatment options for carbapenem-resistant Enterobacteriaceae. Some of the emerging carbapenemase resistant Enterobacteriaeae that are causing multi-drug resistant systemic infections include Escherichia coli, Klebsiellae pneumoniae, Providencia rettgeri, Proteus mirabili, Pantoea species, Citrobacter koseri and Acinetobacter baumanii. There is therefore the need for alternative treatment regimens for carbapenem-resistant Enterobacteriaceae. This study determined the in vitro efficacy of Alchornea cordifolia on carbapenem-resistant Enterobacteriaceae using agar well diffusion and well microplate dilution method. Serial dilutions of the ethanolic crude extract of the leaves were prepared and used against the carbapenem-resistant Enterobacteriaceae. The phytochemical screening was also performed to determine the antibacterial compounds. The christmas bush leaves extracts concentrations ranging from 50 mg/ml – 200 mg/ml showed active diameter zone of inhibition. The ethanolic extract of Christmas bush leaves had minimum inhibition concentration and minimum bactericidal concentration of 3.13mg/ml indicating significant antibiotic activity against the carbapenem-resistant Enterobacteriaceae. The phytochemical screening of the Christmas bush leaves showed the presence of antimicrobial phytochemicals such as flavonoids. This offers the possibility of developing effective antimicrobial agent to treat multi-drug resistant systemic infections. Therefore, there is the need to determine the toxicological effect and perform clinical trials of the active antimicrobial compounds isolated in the leave extracts of Christmas bush shrub. Keywords: Alchornea cordifolia, Flavonoids, Antibacterial, Carbapenem-resistant Enterobacteriaceae DOI: 10.7176/JNSR/10-10-03 Publication date:May 31st 202

The spectrum of heart disease in adults in Malawi: A review of the literature with reference to the importance of echocardiography as a diagnostic modality

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New Record for the Coffee Berry Borer, Hypothenemus hampei, in Hawaii

The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae) is endemic to Africa and is the most devastating pest of coffee worldwide. The female bores a hole in the coffee berry and deposits her eggs inside. Upon hatching, larvae feed on the seeds, thus reducing both quality and yields of the marketable product. The coffee berry borer was found in the district of Kona on the island of Hawaii in August 2010 and appears to be restricted to that area

Antimicrobial Activity of Psidium Guajava (Guava) Leaves Extract on Extended-Spectrum Beta-Lactamase-Producing Klebsiella Pneumoniae that Cause Multi-Drug Resistant Urinary Tract Infections

Extended-spectrum beta-lactamases (ESBLs) are plasmid-mediated enzymes commonly found in the Enterobacteriaceae that are capable of hydrolysing ß-lactams except carbapenems and cephamycins. ESBLs also confer resistance to several non-ß-lactam antibiotics. ESBL producing isolates are predominantly Klebsiella pneumoniae and Eschericia coli. Klebsiella pneumoniae are one of the most common causes of urinary tract infections such as cystitis and pyelonephritis developed by about 150 million people in every given year. ESBL-producing Klebsiella pneumoniae appear susceptible to cephalosporins in vitro using conventional breakpoints but ineffective in vivo. This has limited treatment options for urinary tract infections caused by extended-spectrum beta-lactamases -producing K. pneumoniae. This study determined the in vitro efficacy of Psidium guajava on extended-spectrum beta-lactamases -producing K. pneumoniae using agar well diffusion and well microplate dilution method. Serial dilutions of the ethanolic extract of the leaves were prepared and tested against the extended-spectrum beta-lactamases-producing K. pneumoniae. The phytochemical screening was performed to determine the antibacterial compounds. The guava leaves extracts concentrations ranging from 50 mg/ml – 200 mg/ml showed active diameter zone of inhibition. The ethanolic extract of guava leaves had minimum inhibition concentration and minimum bactericidal concentration of 6.25mg/ml indicating significant antibiotic activity against the ESBL isolates. The phytochemical screening of the guava leaves showed the presence of antimicrobial phytochemicals such as flavonoids. Ethanolic extracts of guava leaves is proving to be efficacious against multi-drug resistant ESBL-producing K. pneumoniae, which a major cause urinary tract infections. This offers hope for the development of effective antibiotics against multi-drug resistant urinary tract infections due to the presence of flavonoids in the guava leaf extracts. Therefore, there is the need to determine the toxicological effect of the active antimicrobial compounds isolated in the leaf extracts of guava plant. Keywords: Psidium guajava, Flavonoids, Multi-drug resistant, Extended-spectrum beta-lactamase, Klebsiella pneumoniae DOI: 10.7176/JNSR/11-22-02 Publication date: November 30th 202