Low Current Performance Research Articles

Development of a Follow-Up Measure to Ensure Complete Screening for Colorectal Cancer

The current quality performance measure for colorectal cancer (CRC) screening is limited to initial screening. Despite low rates, there is no measure for appropriate follow-up with colonoscopy after receipt of an abnormal result of a stool-based screening test (SBT) for CRC. A quality performance measure is needed. To develop and test a quality performance measure for follow-up colonoscopy within 6 months of an abnormal result of an SBT for CRC. This retrospective quality improvement study examined data from January 1, 2016, to December 31, 2020, with 2018 plus 6 months of follow-up as the primary measurement period to verify performance rates, specify a potential measure, and test for validity, reliability, and feasibility. The Optum Labs Data Warehouse (OLDW), a deidentified database of health care claims and clinical data, was accessed. The OLDW contains longitudinal health information on enrollees and patients, representing a diverse mixture of ages and geographic regions across the US. For the database study, adults from 38 health care organizations (HCOs) aged 50 to 75 years who completed an initial CRC SBT with an abnormal result were observed to determine follow-up colonoscopy rates within 6 months. Rates were stratified by race, ethnicity, sex, insurance, and test modality. Three HCOs participated in the feasibility field testing. Data were analyzed from June 1, 2022, to May 31, 2023. The primary outcome consisted of follow-up colonoscopy rates following an abnormal SBT result for CRC. Reliability statistics were also calculated across HCOs, race, ethnicity, and measurement year. Among 20 581 adults (48.6% men and 51.4% women; 307 [1.5%] Asian, 492 [7.2%] Black, 644 [3.1%] Hispanic, and 17 705 [86.0%] White; mean [SD] age, 63.6 [7.1] years) in 38 health systems, 47.9% had a follow-up colonoscopy following an abnormal SBT result for CRC within 6 months. There was significant variation between HCOs. Notably, significantly fewer Black patients (37.1% [95% CI, 34.6%-39.5%]) and patients with Medicare (49.2% [95% CI, 47.7%-50.6%]) or Medicaid (39.2% [95% CI, 36.3%-42.1%]) insurance received a follow-up colonoscopy. A quality performance measure that tracks rates of follow-up within 6 months of an abnormal SBT result was observed to be feasible, valid, and reliable, with a median reliability statistic between HCOs of 94.5% (range, 74.3%-99.7%). The findings of this observational study of 20 581 adults suggest that a measure of follow-up colonoscopy within defined periods after an abnormal result of an SBT test for CRC is warranted based on low current performance rates and would be feasible to collect by health systems and produce valid, reliable results.

Effect of External load and Salt Concentration on the Performance of Microbial Desalination Cell

Microbial desalination cell (MDC) is one of the cost and energy effective methods that can help people in countries with low income and people in rural areas without energy infrastructure, get access to desalinated water while treating their wastewater. Despite the advantages of the technology, less is known about the behavior of the internal resistance in MDCs. Therefore, this study mainly focused on the behavior of the MDC from internal and external resistance point of view. The desalination rate of saltwater at different applied external resistance (995 , 464 , 220 , and 74 ) was studied. Moreover, the polarization capacity of the established MDC was investigated. The internal resistance of MDC at different salt concentrations of the desalination chamber (35-1 g/l) was also analyzed and discussed. The findings of the study showed that decreasing the external resistance could increase the current generation of the MDC as the main driving force of the desalination. Furthermore, it was found that salt concentration in the middle chamber plays a significant role on the internal resistance of MDC and hence on the desalination rate. Lower desalination rate at the lower salt concentration of the desalination chamber could be explained by the high internal resistance of the system. Therefore, integrating MDC with other suitable techniques, e.g., reverse osmosis (RO), for desalination of lower salt concentrations could overcome this challenge. MDC as a standalone desalination system at the current stage of technology might not be practical due to the low current performance of the system. However, it is worth considering it as green and low-cost technology for the pretreatment stage of the other conventional desalination systems, like RO with energy and cost savings while treating the wastewater.

Взаємозв’язок показників поточної та екзаменаційної успішності вивчення фармакології здобувачами вищої фармацевтичної освіти як індикатор для моніторингу якості освіти

У системі підготовки майбутніх спеціалістів фармації фармакологія займає перехідну позицію між базовими фундаментальними (біологія, фізіологія з основами анатомії людини, патофізіологія, біологічна хімія, мікробіологія з основами імунології) та спеціальними профільними предметами (фармакотерапія, клінічна фармація, фармацевтична опіка). Цілком обґрунтовано фармакологія вважається інтегральною дисципліною, що формує професійне мислення як провізорів (фармацевтів), так і лікарів. Тому не викликає сумнівів важливість постійного вдосконалення методик викладання фармакології в закладах вищої медичної та фармацевтичної освіти, а також визначення успішності засвоєння матеріалу дисципліни як універсального індикатора ефективності навчання. Мета дослідження – оцінити успішність вивчення фармакології майбутніми спеціалістами фармації (вітчизняними та іноземними здобувачами вищої освіти) за результатами аналізу підсумкових оцінок, балів за письмовий курсовий іспит і відсотків правильних відповідей з дисципліни на ліцензійному тестовому іспиті КРОК-1 «Фармація», а також розробити процесну модель діяльності з підвищення якості підготовки з фармакології. Встановлено, що в цілому вітчизняні здобувачі вищої фармацевтичної освіти докладають найбільших зусиль до складання іспиту КРОК-1, що визначено за кращими результатами іспиту КРОК-1 порівняно з поточним рейтингом і курсовим іспитом. Іноземні здобувачі вищої фармацевтичної освіти мають нижчу поточну успішність і гірше, ніж вітчизняні, складають ліцензійний іспит КРОК-1. Кореляційний аналіз показав статистично значущі взаємозв’язки між поточним рейтингом, курсовим іспитом і відсотком правильних відповідей тесту КРОК-1 з фармакології. Проте у вітчизняних здобувачів вищої освіти зв’язки між поточним рейтингом і результатом іспиту КРОК-1 й результатами курсового та ліцензійного іспитів сильніші, ніж в іноземних, що може свідчити про більшу увагу до фундаментальних знань у процесі підготовки та складанні іспиту КРОК-1. Запропоновано процесну модель діяльності з покращання успішності вивчення фармакології та підвищення фармакологічної компетентності майбутніх фармацевтів відповідно до стандартів ISO 9001:2015.

Hierarchical macropore-mesoporous shell carbon dispersed with Li4Ti5O12 for excellent high rate sub-freezing Li-ion battery performance

The significant reduction in capacity and cyclability of lithium-ion batteries (LIBs) at low temperature is still limiting its application in cold climate. Limited literature has addressed the low temperature performance of LIB anodes, mostly restrict to low current performance showing low durability (<100 cycles). This is the first report of excellent durability in Li4Ti5O12-based composite cycling at a high current (10C) over 1000 cycles under sub-zero temperatures. We embed Li4Ti5O12 nanoparticles in hierarchical macropore-mesoporous shell carbon network (HCMS carbon) to form Li4Ti5O12/HCMS carbon nanocomposite. The HCMS carbon is an ideal support for Li4Ti5O12 to achieve excellent high rate sub-freezing LIB performance by providing short, intertwining Li-ion diffusion pathways between embedded Li4Ti5O12 particles and Li-ion reservoirs, and ample routes for continuous, multi-directional electron flow to Li4Ti5O12 particles. At −20 °C, the Li4Ti5O12/HCMS carbon composite delivers the highest literature-reported specific energy of 80 Wh/kg at a high specific power of 3000 W/kg. This work demonstrates our Li4Ti5O12/HCMS carbon composite can be a viable LIB anode material with fast and efficient Li-ion and electron transport active in sub-zero temperature operation.

Low current performance of the Bern medical cyclotron down to the pA range

A medical cyclotron accelerating H− ions to 18 MeV is in operation at the Bern University Hospital (Inselspital). It is the commercial IBA 18/18 cyclotron equipped with a specifically conceived 6 m long external beam line ending in a separate bunker. This feature is unique for a hospital-based facility and makes it possible to conduct routine radioisotope production for PET diagnostics in parallel with multidisciplinary research activities, among which are novel particle detectors, radiation biophysics, radioprotection, radiochemistry and radiopharmacy developments. Several of these activities, such as radiobiology experiments for example, require low current beams down to the pA range, while medical cyclotrons are designed for high current operation above 10 μA. In this paper, we present the first results on the low current performance of a PET medical cyclotron obtained by ion source, radio-frequency and main coil tuning. With this method, stable beam currents down to () pA were obtained and measured with a high-sensitivity Faraday cup located at the end of the beam transport line.

Bipolar transistor design for improved low current performance

It is shown that by reducing the doping in the vicinity of the emitter-base junction, the low bias emitter-base capacitance can be greatly reduced and the low-current transistor cut-off frequency ( ƒ t ) increased by several times relative to a conventional double-diffused transistor profile of the same vertical scaling. It is also shown that the reduction in emitter-base capacitance leads to improved noise performance in fiber-optic photodiode preamplifier applications. A low emitter-base concentration or LEBC transistor structure is examined where a very lightly doped or intrinsic layer is inserted between the neutral base and emitter regions. Expressions for the delay time in this intrinsic region are studied and analytic design equations are developed for maximizing transistor ƒ t at a given collector current bias.

A wide-band current-controlled oscillator using bipolar-JFET technology

A new monolithic current-controlled oscillator, which features a highly linear frequency range of more than seven decades, has been realized in a compatible JFET-bipolar technology. Low current performance is accomplished by the use of two p-channel JFET-source-followers and a special load consisting of a string of diodes driven by a continuous current source. Temperature compensation for frequency and output voltage is easily achievable by means of a PTAT current source.