Laser-induced filaments have been shown to reduce the voltage necessary to initiate electrical discharges in atmospheric air and guide their propagation over long distances. Here we demonstrate the stable generation of laser filament-guided electrical discharge columns in air initiated by high energy (up to 250 mJ) 1030 nm wavelength laser pulses of 7 ps duration at repetition rates up to 1 kHz and we discuss the processes leading to breakdown. A current proportional to the laser pulse energy is observed to arise as soon as the laser pulse arrives, initiating a high impedance phase of the discharge.
View Article and Find Full Text PDFWe demonstrate a room-temperature Ti:Sapphire (Ti:Sa) amplifier that uses a cross pump-seed geometry (cross-thin-slab) to generate 30-mJ output pulses at 0.5-kHz repetition rate, and 25 mJ at 1 kHz when pumped by 100-mJ, 515-nm pulses from a diode-pumped Yb:YAG laser. The geometry allows to maintain a crystal temperature of ∼30°C using cooling water at 10°C.
View Article and Find Full Text PDFCoagulation factor Xa (recombinant), inactivated-zhzo (andexanet alfa) is approved for reversal of life-threatening bleeding with rivaroxaban and apixaban use. Clinical decision-making to initiate reversal is reliant on dose taken and timing of last dose. In practice, timing of last dose may be unknown, and the turnaround time for drug-specific anti-factor Xa levels at some institutions may be prolonged, leaving clinicians balancing a difficult decision with limited tools.
View Article and Find Full Text PDFObjective: Intracranial hypertension is a life-threatening condition that requires emergent diagnosis and management. Although pentobarbital coma for refractory intracranial hypertension has been studied in the general population, this study is the first reported case of pentobarbital coma use in a pregnant patient.
Methods: We performed a retrospective chart review of a pregnant patient with refractory intracranial hypertension and reviewed the current literature on the role of pentobarbital coma.
Streptococcus pyogenes (Spy) Cas9 has potential as a component of gene therapeutics for incurable diseases. One of its limitations is its large size, which impedes its formulation and delivery in therapeutic applications. Smaller Cas9s are an alternative, but lack robust activity or specificity and frequently recognize longer PAMs.
View Article and Find Full Text PDFIn the face of the COVID-19 pandemic, the need for rapid serological tests that allow multiplexing emerged, as antibody seropositivity can instruct about individual immunity after an infection with SARS-CoV-2 or after vaccination. As many commercial antibody tests are either time-consuming or tend to produce false negative or false positive results when only one antigen is considered, we developed an automated, flow-based chemiluminescence microarray immunoassay (CL-MIA) that allows for the detection of IgG antibodies to SARS-CoV-2 receptor-binding domain (RBD), spike protein (S1 fragment), and nucleocapsid protein (N) in human serum and plasma in less than 8 min. The CoVRapid CL-MIA was tested with a set of 65 SARS-CoV-2 serology positive or negative samples, resulting in 100% diagnostic specificity and 100% diagnostic sensitivity, thus even outcompeting commercial tests run on the same sample set.
View Article and Find Full Text PDFWe demonstrate the generation of 1.1 J pulses of picosecond duration at 1 kHz repetition rate (1.1 kW average power) from a diode-pumped chirped pulse amplification Yb:YAG laser.
View Article and Find Full Text PDFPredictive equations (PE) are used in lieu of indirect calorimetry (IC) due to cost and limited resources; however, these equations may not be as accurate as IC in estimating resting energy expenditure (REE) in critically ill patients, putting them at risk of malnutrition. The purpose of this study is to compare predicted and measured energy expenditure (MEE) in critically ill adults with acute brain injury. This was a retrospective review of adult patients admitted to the Neurosciences ICU with acute brain injury between May 1st, 2014 and April 1st, 2016 who had IC performed.
View Article and Find Full Text PDFBackground: The majority of patients with hemorrhagic stroke experience enhanced renal clearance or augmented renal clearance (ARC). The purpose of this study was to determine the impact of enhanced renal clearance or ARC on vancomycin pharmacokinetic (PK) parameters.
Methods: This was a post hoc analysis of a prospective study of adult patients with aneurysmal subarachnoid hemorrhage (aSAH) or intracerebral hemorrhage (ICH) admitted to the neurosciences intensive care unit who received vancomycin.
Objectives: To evaluate enhanced renal clearance over time in patients with aneurysmal subarachnoid hemorrhage or intracerebral hemorrhage via measured creatinine clearance and to compare measured creatinine clearance to creatinine clearance calculated by the Cockcroft-Gault equation and estimated glomerular filtration rate calculated by the Modification of Diet in Renal Diseases equation.
Design: Prospective, observational study.
Setting: Neurosciences ICU in a tertiary care academic medical center.
Due to an error introduced during the production process, J. Dedrick Jordan's name was improperly tagged in the original publication of this article. It is tagged correctly here.
View Article and Find Full Text PDFHeat generation is a key obstacle to scaling high energy solid-state lasers to the multi-kilowatt average powers required for several key applications. We demonstrate an accurate, in situ, noninvasive optical technique to that makes three-dimensional (3-D) temperature maps within cryogenic amplifiers operating at high average power. The temperature is determined by analyzing the fluorescence spectra with a neural network function.
View Article and Find Full Text PDFBackground: Early-onset pneumonia (EOP) after endotracheal intubation is common among critically ill patients with a neurologic injury and is associated with worse clinical outcomes.
Methods: This retrospective cohort study observed outcomes pre- and post-implementation of an EOP prophylaxis protocol which involved the administration of a single dose of ceftriaxone 2 g around the time of intubation. The study included patients ≥ 18 years who were admitted to the University of North Carolina Medical Center (UNCMC) neuroscience intensive care unit (NSICU) between April 1, 2014, and October 26, 2016, and intubated for ≥ 72 h.
Although effective programmes are available and several countries have seen substantial declines in new HIV infections, progress in the reduction of adult HIV incidence has been slower than expected worldwide and many countries have not had large decreases in new infections in adults despite large reductions in paediatric infections. Reasons for slow progress include inadequate commitment, investment, focus, scale, and quality of implementation of prevention and treatment interventions. The UNAIDS-Lancet Commission on Defeating AIDS-Advancing Global Health reported that the provision of large-scale, effective HIV prevention programmes has failed and called on stakeholders to "get serious about HIV prevention".
View Article and Find Full Text PDFThe goals of the international response to control the HIV epidemic include high antiretroviral therapy (ART) coverage with HIV viral suppression, as well as reduction of new infections. ART use at individual and population levels reduces HIV morbidity and mortality and likely reduces HIV incidence. HIV viral suppression requires high levels of ART adherence, which necessitates support through behavioural and structural interventions to optimise effectiveness of the use of ART for prevention.
View Article and Find Full Text PDFObjective: To synthesize the data available--on costs, efficiency and economies of scale and scope--for the six basic programmes of the UNAIDS Strategic Investment Framework, to inform those planning the scale-up of human immunodeficiency virus (HIV) services in low- and middle-income countries.
Methods: The relevant peer-reviewed and "grey" literature from low- and middle-income countries was systematically reviewed. Search and analysis followed Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines.
The women, men, and transgender people who sell sex globally have disproportionate risks and burdens of HIV in countries of low, middle, and high income, and in concentrated and generalised epidemic contexts. The greatest HIV burdens continue to be in African female sex workers. Worldwide, sex workers still face reduced access to needed HIV prevention, treatment, and care services.
View Article and Find Full Text PDFObjectives: To review the literature on the potential efficiency gains of integrating HIV services with other health services.
Design: Systematic literature review. Search of electronic databases, manual searching and snowball sampling.
The impact of HIV on maternal mortality and more broadly on the health of women, remains poorly documented and understood. Two recent reports attempt to address the conceptual and methodological challenges that arise in estimating HIV-related maternal mortality and trends. This paper presents and compares the methods and discusses how they affect estimates at global and regional levels.
View Article and Find Full Text PDFQuantitative studies indicate that HIV incidence in Zimbabwe declined since the late 1990s, due in part to behavior change. This qualitative study, involving focus group discussions with 200 women and men, two dozen key informant interviews, and historical mapping of HIV prevention programs, found that exposure to relatives and close friends dying of AIDS, leading to increased perceived HIV risk, was the principal explanation for behavior change. Growing poverty, which reduced men's ability to afford multiple partners, was also commonly cited as contributing to reductions in casual, commercial and extra-marital sex.
View Article and Find Full Text PDFBackground: Recent data from antenatal clinic (ANC) surveillance and general population surveys suggest substantial declines in human immunodeficiency virus (HIV) prevalence in Zimbabwe. We assessed the contributions of rising mortality, falling HIV incidence and sexual behaviour change to the decline in HIV prevalence.
Methods: Comprehensive review and secondary analysis of national and local sources on trends in HIV prevalence, HIV incidence, mortality and sexual behaviour covering the period 1985-2007.
Innate regulatory networks within organs maintain tissue homeostasis and facilitate rapid responses to damage. We identified a novel pathway regulating vessel stability in tissues that involves matrix metalloproteinase 14 (MMP14) and transforming growth factor beta 1 (TGFbeta(1)). Whereas plasma proteins rapidly extravasate out of vasculature in wild-type mice following acute damage, short-term treatment of mice in vivo with a broad-spectrum metalloproteinase inhibitor, neutralizing antibodies to TGFbeta(1), or an activin-like kinase 5 (ALK5) inhibitor significantly enhanced vessel leakage.
View Article and Find Full Text PDFFoot Ankle Surg
March 2009
Background: Curettage of benign tumours commonly results in significant bone defects that are reconstructed with autologous grafts, allografts, bone cement or bone substitute. We have treated such defects in the talus without reconstruction with bone or any other material. We now report the healing of these ungrafted defects in eight patients treated with curettage for benign talar tumours.
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