A study of head and neck space infections and their sensitivity pattern at tertiary care hospital

<p class="abstract"><strong>Background:</strong> Head and neck space infections including submandibular, buccal, diffuse neck space, peritonsillar, parapharyngeal, parotid, submental, retropharyngeal, result in frequent hospital visits. Infection can be mild or severe life threatening infection.</p><p class="abstract"><strong>Methods:</strong> 40 patients with head and neck space infections were considered. Pus samples were collected with aseptic precautions and sent to department of microbiology for culture and antibiotic sensitivity. </p><p class="abstract"><strong>Results:</strong> The most common head and neck space infections are submandibular followed by buccal, diffuse neck abscess, peritonsillar, parapharyngeal, parotid, submental and retropharyngeal. Incidence of aerobic growth is 60%, fungal 10%, anaerobic 7.5%, tubercular 7.5% and no growth 15%. Predominant aerobes are <em>Staphylococcus aureus</em>, <em>Pseudomonas aeruginosa</em>, Methicillin Resistant<em> Staphlococcus aureus</em>, <em>Klebsiella</em> species and anaerobes are Peptostreptococcus and bacteroides and fungal species is <em>Candida</em>. Aerobic organism showed maximum sensitivity to Amikacin, Vancomycin, Linezolid, Piperacillin+Tazobactum, Clindamycin, Erythromycin, Cefoperazone, Ceftriaxone and maximum resistant to Levofloxacin, Cefoperazone, Ceftriaxone, Meropenem. Anaerobic bacteria showed sensitivity to Clindamycin, Metronidazole and Colistin and resistance to Vancomycin.</p><p class="abstract"><strong>Conclusions:</strong> Bacteriological examination and culture of head and neck abscesses helps to identify causative organisms. It helps to isolate even rarest of organisms and by knowing their sensitivity pattern we can detect specific therapy against them. Thus it helps in more effective treatment and fast recovery.</p>

Formability of Al 5xxx Sheet Metals Using Pulsed Current for Various Heat Treatments

Previous studies have shown that the presence of a pulsed electrical current, applied during the deformation process of an aluminum specimen, can significantly improve the formability of the aluminum without heating the metal above its maximum operating temperature range. The research herein extends these findings by examining the effect of electrical pulsing on 5052 and 5083 aluminum alloys. Two different parameter sets were used while pulsing three different heat-treatments (as-is, 398°C, and 510°C) for each of the two aluminum alloys. For this research, the electrical pulsing is applied to the aluminum while the specimens are deformed without halting the deformation process (a manufacturing technique known as electrically assisted manufacturing). The analysis focuses on establishing the effect of the electrical pulsing has on the aluminum alloy’s various heat-treatments by examining the displacement of the material throughout the testing region of dogbone-shaped specimens. The results from this research show that pulsing significantly increases the maximum achievable elongation of the aluminum (when compared with baseline tests conducted without electrical pulsing). Another beneficial effect produced by electrical pulsing is that the engineering flow stress within the material is considerably reduced. The electrical pulses also cause the aluminum to deform nonuniformly, such that the material exhibits a diffuse neck where the minimum deformation occurs near the ends of the specimen (near the clamps) and the maximum deformation occurs near the center of the specimen (where fracture ultimately occurs). This diffuse necking effect is similar to what can be experienced during superplastic deformation. However, when comparing the presence of a diffuse neck in this research, electrical pulsing does not create as significant of a diffuse neck as superplastic deformation. Electrical pulsing has the potential to be more efficient than the traditional methods of incremental forming since the deformation process is never interrupted. Overall, with the greater elongation and lower stress, the aluminum can be deformed quicker, easier, and to a greater extent than is currently possible.

Effect of Electrical Pulsing on Various Heat Treatments of 5XXX Series Aluminum Alloys

Previous studies have shown that the presence of a pulsed electrical current, applied during the deformation process of an aluminum specimen, can significantly improve the formability of the aluminum without heating the metal above its maximum operating temperature range. The research herein extends these findings by examining the effect of electrical pulsing on 5052 and 5083 Aluminum Alloys. Two different parameter sets were used while pulsing three different heat treatments (As Is, 398°C, and 510°C) for each of the two aluminum alloys. For this research, the electrical pulsing is applied to the aluminum while the specimens are deformed, without halting the deformation process. The analysis focuses on establishing the effect the electrical pulsing has on the aluminum alloy’s various heat treatments by examining the displacement of the material throughout the testing region of dogbone shaped specimens. The results from this research show that pulsing significantly increases the maximum achievable elongation of the aluminum (when compared to baseline tests conducted without electrical pulsing). Significantly reducing the engineering flow stress within the material is another beneficial effect produced by electric pulsing. The electrical pulses also cause the aluminum to deform non-uniformly, such that the material exhibits a diffuse neck where the minimum deformation occurs near the ends of the specimen (near the clamps) and the maximum deformation occurs near the center of the specimen (where fracture ultimately occurs). This diffuse necking effect is similar to what can be experienced during superplastic deformation. However, when comparing the presence of a diffuse neck in this research, electrical pulsing does not create as significant of a diffuse neck as superplastic deformation. Electrical pulsing has the potential to be more efficient than traditional methods of incremental forming since the deformation process is never interrupted. Overall, with the greater elongation and lower stress, the aluminum can be deformed quicker, easier, and to a greater extent than is currently possible.

Effect of Thickness on the Pure Stretchability of Aluminum Sheets

The effects of the thickness, lubricant, and temper of metals on pure stretchability of aluminum sheets have been studied. The pure stretchability of the sheet metals was markedly deteriorated by decreasing both the thickness in every lubricant and the temper of metal used in this experiment. The optimum frictional coefficient, which gives a maximum of the critical forming depth, was found in this experiment, and it was confirmed to change with the thickness and temper of metal. The thickness dependence of the critical forming depth was analytically calculated by means of Hill’s diffuse neck criterion, Yamaguchi’s method based on M-K theory and the criterion proposed by Gotoh. The result calculated by Yamaguchi’s method was comparatively in good agreement with the experiment in soft aluminum sheet and the result by Gotoh’s method did so in the half-hard one.