Solubilization of Reactive Red 2 in the Mixed Micelles of Cetylpyridinium Chloride and TX-114.

Owing to their surface active properties, surfactants have numerous applications in different fields of life. In the present research work, the solubilization of reactive red 2 (RR2) has been studied in single and mixed micellar systems (MMS) using UV-visible spectroscopy and electrical conductivity measurements. The interaction of RR2 with ionic micelles of cetylpyridinium chloride (CPC) was investigated. In order to probe the interaction of RR2 in MMS, mixtures of CPC and TX-114 (Triton X-114, a nonionic surfactant) were used. UV-visible spectroscopy has been used to obtain the degree of solubilization of RR2 in terms of the partition coefficient (Kc) and Gibbs free energy of partitioning (ΔG°p). Electrical conductivity data have been employed to detect the critical micelle concentration (CMC) of the surfactant systems in the presence of RR2 and, accordingly, to calculate the thermodynamic parameters of the micellization. From the obtained data, it is concluded that the micellization is spontaneous at all studied temperatures. Moreover, the micellization was observed to be driven by both enthalpy and entropy. The results also indicated that MMS have better solubilizing power than single micellar solutions.

Real-Time Optical Monitoring of Endotracheal Tube Displacement.

Proper ventilation of a patient with an endotracheal tube (ETT) requires proper placement of the ETT. We present a sensitive, noninvasive, operator-free, and cost-effective optical sensor, called Opt-ETT, for the real-time assessment of ETT placement and alerting of the clinical care team should the ETT become displaced. The Opt-ETT uses a side-firing optical fiber, a near-infrared light-emitting diode, two photodetectors with an integrated amplifier, an Arduino board, and a computer loaded with a custom LabVIEW program to monitor the position of the endotracheal tube inside the windpipe. The Opt-ETT generates a visual and audible warning if the tube moves over a distance set by the operator. Displacement prediction is made using a second-order polynomial fit to the voltages measured from each detector. The system is tested on ex vivo porcine tissues, and the accuracy is determined to be better than 1.0 mm. In vivo experiments with a pig are conducted to test the performance and usability of the system.

Calcitonin negative medullary thyroid cancer in ectopic thyroid tissue: a rare diagnosis in an unusual location.

Medullary thyroid cancer is an aggressive form of thyroid cancer arising from parafollicular C cells. Calcitonin (CT) is a specific and sensitive biochemical marker which typically aids primary diagnosis and disease surveillance following treatment. There are rare cases of calcitonin negative medullary thyroid cancer (CNMTC) documented in the literature; however, to our knowledge, this case is the first report of CNMTC arising in ectopic thyroid tissue. We report a case of a 45-year-old man who attended his primary care physician with painless anterior neck swelling. In the absence of CT secreting disease, we have demonstrated the investigative process and the importance of immunohistochemical analysis to achieve a diagnosis. We also consider the challenges of monitoring disease recurrence in the absence of reliable biochemical markers.

Terahertz spectroscopy of Bisphenol "A", "AF", "S", "E" and the interrelationship between their molecular vibrations.

Bisphenol "A" is a widespread environmental hormone. After the prohibition on the use of BPA in some applications, it is progressively replaced by its variants. However, these variants of Bisphenol "A" are also noxious. It is therefore of the utmost importance to find the similarity among these materials and put all of them under restriction to avoid harmful effects. Therefore, Bisphenol "A", "AF", "E", and "S" are studied by Terahertz spectroscopy (0.5-2.5 THz). Various molecular vibrations are found and assigned based on density-functional-theory calculations. Refractive Indices are calculated as well. The principal component analysis reveals the critical vibrational frequencies for their detection and shows the correlation between them.

Molecular vibrations of bisphenol "S" revealed by FTIR spectroscopy and their correlation with bisphenol "A" disclosed by principal component analysis.

Bisphenol "S" (BPS), a common replacement for bisphenol "A" (BPA) after its ban in food contact applications, is studied by Fourier transform infrared (FTIR) spectroscopy (400-6800 cm-1). Identified molecular vibrations are assigned based on density functional theory calculations. As BPS is suspected to be as toxic as BPA, principal component analysis is used to find possible correlations among their molecular vibrations. We have found frequencies showing a connection between these two materials via molecular vibrations, helping not only to categorize such materials but also to find the origin of their toxicity.

Liposarcoma of the retropharyngeal space.

Liposarcoma is a common soft tissue malignancy that occurs infrequently in the head and neck. Liposarcoma of the retropharynx is exceptionally rare, only four cases being described in the literature. We present a case in which retropharyngeal liposarcoma occurred in a patient who had had multiple previous subcutaneous lipomas excised. This paper explores this very unusual presentation and discusses the difficulties in the diagnosis and management of this rare tumour.

Noise exposure in orthopaedic practice: potential health risk.

Noise exposure is one of the major causes of permanent hearing loss in society. Exposure of health service staff to intense levels of noise in the workplace is a potential risk for the development of temporary and permanent hearing loss. In this prospective study, 18 members of the orthopaedic staff underwent hearing assessment by pure tone audiometry and speech discrimination prior to noise exposure at the workplace and immediately following cessation of work. The number of hours of exposure and noise levels in the workplace was also analysed. Only minimal temporary sensorineural threshold shifts were detected post-noise exposure. There was no change in speech discrimination scores and no individuals complained of tinnitus. The number of hours of exposure ranged from 1.5 to 8.5 hours (mean 5.2 hours). Recorded sound levels for instruments ranged from 119.6 dB at source to 73.1 decibels at 3 metres. Although high sound levels are recorded in the orthopaedic operating theatre, the intermittent nature exposure to the intense noise may protect staff against hearing loss, speech discrimination difficulties and tinnitus.