A 3×4 drop-plating protocol for estimation of Antimicrobial-resistant bacteria, taking Extended-spectrum beta-lactamases producing Escherichia coli as an example.

The estimation of antimicrobial-resistant (AMR) bacteria plays an important role in risk assessment and surveillance. To test the concentration of resistant bacteria with colony count is a fast and straightforward way to perform. Here we describe an optimized drop-plating method for colony counting of resistant bacteria. We took the ESBL-producing E. coli in freshwater samples as an example. The optimized methods can successfully quantify ESBL-producing E. coli of water samples in a concentration range of 104 CFU/L to 106 CFU/L. We have shown that this drop-plating method is comparable to the direct spreading method by testing with both methods on a series of simulated samples, which were constructed using raw surface water spiked with different concentrations of ESBL-producing E. coli. The ESBL-producing phenotype has been further confirmed with the double-disc synergy test. Compared to direct spread methods, our methods can save consumables and operate with smaller sample sizes. Therefore, this method could be more sustainable in AMR surveillance and risk assessment.

Adaptive signal processing for infrared wireless CDMA systems

Infrared system provides a feasible alternative to radio system for indoor wireless communication. Direct spread CDMA format is a promising candidate for infrared transmission system. In indoor systems, transmission is severely impaired by noise and interference produced by artificial light. In this thesis, the performance of the DS CDMA indoor wireless infrared system on diffuse channels is analyzed by taking the effects of inter symbol interference (ISI) and electronic ballast florescent light interference into account. Moreover, to mitigate the effects of ISI and electronic ballast florescent light interference, an adaptive filter technique is proposed for noise cancellation and equalization. This is done by considering a ceiling bounce model for the channel and electronic ballast florescent light for noise. Analytical and simulation results show 7dB improvement in SINR and 10-15 times improvement in BER.

Adaptive signal processing for infrared wireless CDMA systems

Infrared system provides a feasible alternative to radio system for indoor wireless communication. Direct spread CDMA format is a promising candidate for infrared transmission system. In indoor systems, transmission is severely impaired by noise and interference produced by artificial light. In this thesis, the performance of the DS CDMA indoor wireless infrared system on diffuse channels is analyzed by taking the effects of inter symbol interference (ISI) and electronic ballast florescent light interference into account. Moreover, to mitigate the effects of ISI and electronic ballast florescent light interference, an adaptive filter technique is proposed for noise cancellation and equalization. This is done by considering a ceiling bounce model for the channel and electronic ballast florescent light for noise. Analytical and simulation results show 7dB improvement in SINR and 10-15 times improvement in BER.

Development of an Iliacus Muscle Abscess after School Exercise in a 17-Year-Old Female Student

Primary psoas abscess is due largely to hematogenous or lymphatic spread under immunocompromised conditions, whereas secondary psoas abscess is due largely to direct spread from adjacent infected structures. Trauma or hematoma within the muscle may predispose to the development of a primary abscess, especially if infection is present prior to injury, despite the absence of previous signs or symptoms of infection. This report describes a 17-year-old female high school student who developed an abscess within her iliacus muscle due to methicillin-susceptible <i>Staphylococcus aureus</i> after running 3 km on a hill as a school exercise. She was positive for antinuclear antibody and had had atopic dermatitis, suggesting that these factors, as well as exercise-related minor trauma or hematoma within the muscle, may have predisposed to abscess formation. She was treated with appropriate antibiotics and surgical drainage, resulting in recovery after 4 weeks.

Acute Appendicitis with Perinephric Abscess - A Rare Occurrence

Vermiform appendix previously thought to be a vestigial organ, has a variable length of 2 - 20 cms. It arises from posteromedial wall of cecum, around 2 cms lower than the ileocecal valve. The tip of appendix can be in different directions like retrocecal, pelvic, subcecal, retroileal, preileal, subhepatic and ectopic.1 The appendix is supplied by the appendicular artery, anterior and posterior cecal arteries. Ileocolic and right colic veins drain venous blood of appendix. Ileocolic lymph nodes adjacent to the superior mesenteric artery drains the lymphatics.2 Acute appendicitis remains the commonest cause of acute abdominal pain requiring surgical intervention.3 Acute appendicitis may present as loss of appetite, periumbilical pain, nausea and few episodes of vomiting, associated with low grade fever (38˚ C), there is also signs of peritoneal inflammation in lower abdomen.4 Acute appendicitis is actually a clinical diagnosis and confirmed by laboratory investigations like neutrophilia and radiological studies like ultrasonography abdomen.5 Appendicular perforation, cecal perforation, gangrene, periappendicular abscess, peritonitis, bowel obstruction, septic seeding of mesenteric vessels, and very rarely perinephric abscess are the complications of acute appendicitis.6 Purulent collection between the kidney and Gerota’s fascia is called as perinephric abscess, mostly occurs due to rupture of intrarenal abscess into the space between kidney and Gerota’s fascia, few other causes of perinephric abscess include haematogenous spreading from other sites of infection and direct spread from adjacent viscera, perforated colon carcinoma, diverticulitis and osteomyelitis of adjacent ribs or vertebrae.7

New Constructions of Codebooks Nearly Meeting the Welch Bound

Optimal codebooks meeting the Welch bound with equality are desirable in many areas, such as direct spread code division multiple access communications, compressed sensing and so on. However, it is difficult to construct such optimal codebooks. There have been a number of attempts to construct codebooks nearly meeting the Welch bound. In this paper, we introduce a generic construction of codebooks using generalized bent functions from [Formula: see text] to [Formula: see text], where [Formula: see text] is a prime and [Formula: see text] is a positive integer with [Formula: see text]. With this construction, we obtain two new families of codebooks nearly meeting the Welch bound. These codebooks have new parameters and could have a small alphabet size. In particular, a class of regular generalized bent functions from [Formula: see text] to [Formula: see text] is presented.