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Prostatitis is a common clinical syndrome classified into four categories: acute bacterial, chronic bacterial, chronic prostatitis/chronic pelvic pain syndrome, and asymptomatic. Bacterial prostatitis (acute and chronic) is primarily diagnosed with history and microbiologic studies, although physical examination can be helpful to localize infection within the genitourinary system. Bacterial prostatitis is treated with antibiotics; the span of treatment is guided by the duration of symptoms and presence of complications. Chronic prostatitis/chronic pelvic pain syndrome is the most common form of prostatitis and is a diagnosis of exclusion with no standardized treatments. Asymptomatic prostatitis does not require treatment and is usually diagnosed incidentally during the workup for other urologic presentations. [ABSTRACT FROM AUTHOR]

The article focuses on a case of a 69-year-old female who developed progressive facial symptoms following dental work, initially treated with corticosteroids and antibiotics. Topics include the diagnosis and management of post-dental procedure complications, particularly distinguishing between potential causes like giant cell arteritis and local anesthetic reactions, and the importance of timely, accurate diagnosis to prevent serious outcomes such as cranial nerve palsies and vision loss.

Key Clinical Message: Amebic liver abscesses should be considered in adult males with a liver abscess and a history of travel to endemic areas. Effective treatment includes metronidazole, followed by paromomycin. [ABSTRACT FROM AUTHOR]

A lack of clinical response to empiric antimicrobials behooves the clinician to reflect further on diagnostic considerations. When prescribing antibiotics, determining the correct dose, most optimal route of administration, and considering the pharmacokinetic properties of the drug with respect to clinical and patient factors are crucial. Improving antibiotic usage is paramount. Antibiotic prescribing is a purposeful process, requiring a clinical indication, determination of the optimal drug dosage/route of administration, and consideration of clinical pharmacokinetics in a patient. [ABSTRACT FROM AUTHOR]

Although compact fluorescent lamps (CFLs) have been in the market for a long time, many of them do not achieve the same power factor as the incandescent lamps do, which appears to be a significant problem for the utility with the current widespread use of CFLs for household lightings. A single-stage single-switch electronic ballast with active power factor correction is presented in this study for CFL applications. Unlike other single-switch ballast circuits, the presented integrated dual-boost converter circuit can produce a symmetric bipolar square-wave voltage, thus generating a near-pure high-frequency sinusoidal voltage on the lamp, which is beneficial to the CFL lifetime. Moreover, its soft-switching variant can achieve the ZVZC turn-on and ZV turn-off for the MOSFET to improve the conversion efficiency. Detailed operating principles and circuit analysis of the proposed circuit have been provided in this study. Simulation and experimental results on a prototype of a 15 W CFL validate the theoretical analysis and highlight the merits of the presented work. [ABSTRACT FROM AUTHOR]

Tick-borne relapsing fever (TBRF) is an infection caused by Borrelia spirochetes. In North America, Borrelia hermsii is the most common cause for TBRF. This vector-borne disease is transmitted by Ornithodoros hermsi, a soft-bodied tick found in high altitudes in northwestern United States and southwestern Canada. Once bitten by the tick and infected by B. hermsii, episodes of fever alternating with afebrile periods can occur. A case of TBRF in a pregnant host was complicated by Jarisch-Herxheimer reaction requiring critical care. This case emphasizes the importance of maintaining a high index of suspicion in TBRF. Clinician recognition, diagnosis and treatment of TBRF as well as public awareness of strategies to prevent tick bites should be strengthened. [ABSTRACT FROM AUTHOR]

Rationale: Epidemic Pseudomonas aeruginosa (PA) plays an important role in cystic fibrosis (CF) lung disease. A novel strain, the 'Prairie Epidemic Strain' (PES), has been identified in up to 30% of patients in Prairie-based Canadian CF centres.Objective: To determine the incidence, prevalence and long-term clinical impact of PES infection.Methods: A cohort of adults with CF was followed from 1980 to 2014 where bacteria isolated from clinical encounters were prospectively collected. Strain typing was performed using pulse-field gel electrophoresis and multilocus sequence typing. Patients were divided into one of four cohorts: no PA, transient PA, chronic PA with unique strains and chronic PES. Proportional Cox hazard and linear mixed models were used to assess for CF-associated respiratory death or transplantation, and rates of %FEV1 and body mass index (BMI) decline.Results: 274 patients (51.7% male) were analysed: 44--no PA, 29--transient PA, 137--unique PA, 64--PES. A total of 92 patients (33.6%) died or underwent lung transplantation (2423.0 patient-years). PES infection was associated with greater risk of respiratory death or lung transplant compared with the no PA group (aHR, 3.94 (95% CI 1.18 to 13.1); p=0.03) and unique PA group (aHR, 1.75 (95% CI 1.05 to 2.92) p=0.03). Rate of lung function decline (%FEV1 predicted) was greatest in the PES group (1.73%/year (95% CI 1.63% to 1.82%); p<0.001). BMI improved over time but at an attenuated rate in the PES group (p=0.001).Conclusions: Infection with PES was associated with increased patient morbidity through three decades and manifested in an increased risk of respiratory death and/or lung transplantation. [ABSTRACT FROM AUTHOR]

Presents a study that examined the zero-field muon-spin relaxation in (yttrium[sub1-x] praseodymium[subx]) barium[sub2 copper[sub3] oxygen[suby]. Methods; Discussion of muon-spin relaxation; Conclusion.

Background: Neurocysticercosis occurs when the eggs of the pork tapeworm (Taenia solium) migrate and hatch into larvae within the central nervous system. Neurocysticercosis is the most common cause of seizures in the developing world and is characterized on brain imaging by cysts in different stages of evolution. In Canada, cases of neurocysticercosis are rare and most of these patients acquire the disease outside of Canada. We report the case of a patient with multiple intracranial lesions whose history and diagnostic imaging were consistent with neurocysticercosis. Pathological investigations ultimately demonstrated that her brain lesions were secondary to malignancy. Brain metastases are considered to be the most common cause of intracranial cystic lesions. Case Presentation: We present the case of a 60-year-old Canadian-born Caucasian woman with a subacute history of ataxia, lower extremity hyper-reflexia, and otalgia who resided near a pig farm for most of her childhood. Computed tomography and magnetic resonance imaging showed that she had multiple heterogeneous intracranial cysts, suggestive of neurocysticercosis. Despite a heavy burden of disease, serological tests for cysticercosis were negative. This result and a lack of the central scolices on neuroimaging that are pathognomonic of neurocysticercosis prompted whole-body computed tomography imaging to identify another etiology. The whole-body computed tomography revealed right hilar lymphadenopathy associated with soft tissue nodules in her chest wall and abdomen. A biopsy of an anterior chest wall nodule demonstrated high-grade poorly differentiated carcinoma with necrosis, which stained strongly positive for thyroid transcription factor-1 and synaptophysin on immunohistochemistry. A diagnosis of stage 4 metastatic small cell neuroendocrine carcinoma was made and our patient was referred for oncological palliative treatment. Conclusions: This case illustrates the importance of the diagnostic approach to intracranial lesions. Our patient's diagnosis of neuroendocrine carcinoma was delayed because of her nontraditional presentation. Despite extensive metastatic burden, the lack of perilesional edema and the identification of lesions appearing to be in various stages of development led to a pursuit of neurocysticercosis as the diagnosis. The absence of constitutional symptoms should not discount the possibility of malignancy from the differential diagnosis. [ABSTRACT FROM AUTHOR]

Light emitting diode (LED) lamps with ac-input (50 or 60 Hz) usually require an electrolytic capacitor as the dc-link capacitor in the driver circuit to: 1) balance the energy between the input and output power, and 2) to minimize the low-frequency component of the output ripple across the LEDs. The lifetime of this capacitor, however, is much shorter than that of a LED. To maximize the potential lifetime of the LED lighting system, a new pulsating current driving LED driver that does not require any electrolytic capacitors or complicated control circuits to minimize the low-frequency (i.e., 100 or 120 Hz) output ripple is proposed in this paper. The proposed circuit is simple and a single-switch topology is designed to simplify the controller design. The proposed circuit is able to reduce the energy storage capacitance to a few microfarads range, so that film capacitor can be used to replace the unreliable electrolytic capacitor. The circuit operating principles and its theoretical analysis are provided in this paper. Simulation and experimental results are given on a 9-W LED lamp to highlight the merits of the proposed circuit. [ABSTRACT FROM AUTHOR]

With the global concerns on the issue of how to conserve the limited energy resources, compact fluorescent lamps (CFLs) have been forced in a lot of countries to replace the power-hungry incandescent lamps to reduce the energy cost. However, conventional passive power factor corrected electronic ballasts used in CFLs suffer two major drawbacks: 1) they are unable to achieve close-to-unity power factor and 2) they are unable to provide the same amount of light intensity under fluctuating line voltage. This paper proposed a simple lamp power regulation method for a very high-power factor single-switch electronic ballast, which allows the electronic ballast to maintain almost constant lamp power at its full-power condition for a wide range of the input voltage by controlling the dc-link voltage of the ballast power circuit through duty ratio control. When a TRIAC phase-cut dimmer is used to dim the CFL, the dc-link voltage regulation control loop is deactivated; so that the lamp power decreases accordingly during dimming. The analysis and operating principles of the controller are discussed in this paper. MATLAB, PSIM simulation, and experimental results are provided to highlight the merits of the proposed work. [ABSTRACT FROM AUTHOR]

Although compact fluorescent lamps (CFLs) have been on the market for a long time, many of them do not achieve the same power factor as the incandescent lamps do, which presents a significant problem for the utility with the current widespread use of CFLs for household lightings. A simple single-switch electronic ballast with passive valley-fill power factor correction is proposed in this paper for CFL application. The proposed single-switch ballast circuit is able to achieve zero current switching to maximize the circuit efficiency. A simple feedback circuit with duty ratio control is also proposed to improve the high lamp current crest factor caused by the valley-fill circuit. Detailed descriptions and analysis of the circuit operating principles are provided in this paper. Simulation and experimental results are given on a 13-W CFL tube from Osram Sylvania to highlight the merits of the proposed work. [ABSTRACT FROM PUBLISHER]

This paper proposes a novel multifunctional controller for a dimmable high-power-factor single-switch electronic ballast that can be used with standard phase-cut dimmers. Conventional dimmable electronic ballasts lack the ability to 1) provide smooth dimming and maintain high power factor when phase-cut dimmers are used and 2) regulate the lamp power when the input line voltage varies. A digital controller with multiple control functions is proposed in this paper. The proposed controller allows high power factor to be achieved by controlling the duty cycle during dimming with standard phase-cut dimmers. On the other hand, when dimming is not required, the lamp power is regulated through the regulation of the dc-link voltage. Additional control functions, such as lamp low-power cutoff operation, and protection function are also implemented inside the digital controller. The descriptions of the controller operating principles and its logic flow diagrams are provided in this paper. PSIM simulation and experimental results are provided on a 13-W compact fluorescent lamp to highlight the merits of the proposed work. [ABSTRACT FROM AUTHOR]

A novel dimmable high-power-factor compact fluorescent lamp (CFL) electronic ballast that is compatible with standard incandescent lamp dimmers is proposed in this paper. In the proposed system, the dimming controller uses the phase angle of the dimmer as the input feedforward parameter for the duty ratio control of the switch in the power circuit. As a result, a wide range of light output can be achieved with a small range of phase angles of the phase-cut dimmer. The ballast power circuit is a single-switch single-stage resonant inverter, which is essentially a fusion of a SEPIC converter and a single-switch current-fed inverter. Detailed operating principles of the proposed system will be discussed in this paper. System stability analysis that includes the effects of the phase-cut dimmer is also provided. Experimental results are given for a 13-W CFL to demonstrate and highlight the merits of the proposed work. [ABSTRACT FROM AUTHOR]

A novel single-stage single-switch electronic ballast topology with a unity power factor is presented in this paper. The proposed circuit consists of an integrated buck–boost stage that operates in the discontinuous conduction mode to provide a high power factor and a single-switch current-fed resonant inverter to stabilize the lamp current. The proposed topology presents a low cost and compact electronic ballast design method. The detailed descriptions of the circuit's operating principles are provided in this paper. The design equations and mathematical analysis regarding the proposed circuit are discussed in this paper. The proposed ballast has been tested with an 18-W compact fluorescent lamp, and the experimental results confirmed that a very high power factor of 0.995 and an efficiency of 83.4% have been achieved. [ABSTRACT FROM PUBLISHER]

A single-stage dimmable electronic ballast with very high power factor and high efficiency is presented in this paper. A compact lamp power circuit is designed by integrating a buck-boost power factor corrector with a current-fed resonant inverter. This integration produces a single power-processing unit that minimizes the number of circuit components. The proposed resonant inverter reduces the circulating current in the resonant tank and allows simple gate drivers to be used so that isolation devices can be eliminated. With the buck-boost stage operating in the discontinuous conduction mode (DCM), a close-to-unity power factor is achieved for different lamp-power conditions. A small-signal analysis is presented, and a simple variable frequency controller is developed using the modified 555 timer to provide dimming operations. Simulation and experimental waveforms are provided to highlight the merits of the proposed circuit for a 40-W compact fluorescent lamp. [ABSTRACT FROM AUTHOR]

Resonant inverters are connected to a high-frequency ac (HFAC) bus, where power is delivered to different locations for points-of-use power management. Such a power distribution system subjects to more perturbations and load uncertainties than inverters operating with single load. A novel voltage control method is proposed in this paper for a high-frequency full-bridge resonant inverter with series-parallel resonant tank. A modified one-cycle controlled phase-shift modulation is proposed to effectively compensate the input line variations. The uncertainty model of the high frequency resonant inverter is developed and analyzed with the resonant circuit component tolerance, input line and load variations taken into design considerations. The voltage feedback controller is designed based on the H∞ robust control theory and is implemented with analog discrete devices. The proposed control scheme has the advantages of fast response for both input line and load perturbations. It also ensures a wide range of system stability and guarantees robustness of the power converter. Both simulations and experimental results are provided to verify with the theoretical analysis through an experimental prototype of a full-bridge resonant inverter with an output power of 150-W operating at 1 MHz and an output voltage of 28 V (rms). [ABSTRACT FROM AUTHOR]