Exploring the Correlation of Dynamic Surface Tension with Antimicrobial Activities of Quaternary Ammonium-Based Disinfectants.

Quaternary ammonium compound (QAC) disinfectants represent one of our first lines of defense against pathogens. Their inhibitory and bactericidal activities are usually tested through minimum inhibitory concentration (MIC) and time-kill assays, but these assays can become cumbersome when screening many compounds. We investigated how the dynamic surface tension (DST) measurements of QACs correlate with these antimicrobial activities by testing a panel of potent and structurally varied QACs against the gram-positive Staphylococcus aureus and the gram-negative Pseudomonas aeruginosa.

Soft QPCs: Biscationic Quaternary Phosphonium Compounds as Soft Antimicrobial Agents.

Quaternary ammonium compounds (QACs) serve as a first line of defense against infectious pathogens. As resistance to QACs emerges in the environment, the development of next-generation disinfectants is of utmost priority for human health. Balancing antibacterial potency with environmental considerations is required to effectively counter the development of bacterial resistance.

Atom Economical QPCs: Phenyl-Free Biscationic Quaternary Phosphonium Compounds as Potent Disinfectants.

Quaternary ammonium compounds (QACs) are vital disinfectants for the neutralization of pathogenic bacteria in clinical, domestic, and commercial settings. After decades of dependence on QACs, the emergence of antimicrobial resistance to this class of compounds threatens the ability of existing QAC products to effectively manage rising bacterial threats. The need for new disinfectants is therefore urgent, with quaternary phosphonium compounds (QPCs) emerging as a new class of promising antimicrobials that boast significant activity against highly resistant bacteria.

The impact of high BMI on acute changes in body composition following 90 minutes of running.

Objectives: Although physical activity ameliorates the metabolic impact of high body mass index (BMI), runners with BMI≥25 kg/m are relatively understudied.This study had two goals: 1) Identify differences in body composition, as measured by dual X-ray absorptiometry (DXA), between overweight (BMI≥25 kg/m) runners (OWR) and normal weight (BMI<25 kg/m) runners (NWR) and 2) Examine whether an 90 minute run alters total or regional fat mass, as measured by DXA, in OWR and NWR. We hypothesized that OWR would have higher total body fat than NWR and OWR with greater changes in visceral fat after a prolonged run.

Chemical oxygen demand analysis of wastewater using trivalent manganese oxidant with chloride removal by sodium bismuthate pretreatment.

Current chemical oxygen demand (COD) analyses generate wastes containing hexavalent and trivalent chromium, mercury, and silver. Waste disposal is difficult, expensive, and poses environmental hazards. A new COD test is proposed that eliminates these metals and shortens analysis time, where trivalent manganese oxidant replaces hexavalent chromium (dichromate).

Sulfuric acid/hydrogen peroxide digestion and colorimetric a collaborative study.

Seven laboratories participated in a collaborative study of a method for determination of phosphorus in meat and meat products. Samples are digested in sulfuric acid and hydrogen peroxide; digestion is complete in approximately 10 min. Phosphorus is determined by colorimetric analysis of a dilute aliquot of the sample digest.

Efficient and effective root canal retreatment without chloroform.

A root canal retreatment technique is described which eliminates the need for chloroform as a gutta percha solvent. This technique utilizes the gutta percha softening actions of both a self-heating instrument and the heat-potentiated solvent action of eucalyptol. In addition, sonics/ultrasonics and/or Gates-Glidden drills are suggested as useful adjuncts to canal debridement during re-preparation of the canal system.

Evaluation of root canal preparation with two automated endodontic handpieces.

An evaluation of automated low-speed handpiece preparation of canals was made by a silicone injection technique. These preparations were compared and rated with canals prepared by conventional hand instrumentation. Canals were graded on the criteria of shape, smoothness, elimation of morphologic aberrations, and apical preparations.