Observation of R600a flow at subcooled temperature conditions in a vapor compression refrigeration system

Vapor compression refrigeration system is usually designed such that refrigerant exits a condenser at subcooled liquid state in order not to cause possible damage to expansion devices. Even in small refrigeration systems incorporating capillary tube as an expansion device, the refrigerant is supposed to be subcooled before entering the expansion device. In this study, experimental apparatus equipped with several thermocouples, pressure transducers and visualization device was constructed in order to observe the behavior of refrigerant flow at condenser outlet of a vapor compression refrigeration system. Visual observation as well as temperature and pressure readings indicate the presence of two-phase flow at highly subcooled temperature. An alternative equation was suggested to calculate the enthalpy of the two-phase refrigerant in subcooled region and verification test was conducted

Cepstral Analysis of Voice in Patients With Thyroidectomy

Objectives The vocal changes after a thyroidectomy are temporary and nonsevere, therefore, obtaining accurate analytical results on the pathological vocal characteristics following such a procedure is difficult. For a more objective acoustic analysis, this study used the cepstral analysis method to examine changes in the patients’ voices during the perioperative period regarding sustained vowel phonation. Methods The sustained phonation of the five vowels (i.e., /a/, /e/, /i/, /o/, and /u/) by 35 patients with thyroidectomy were recorded by using a Multi-Speech program. Of the 35 patients, 10 were men and 25 were women, with an average age of 51.5 years. Voice data were collected a total of 3 times (preoperatively, 5–7 days after the operation, and 6 weeks after the operation) and were edited according to each fragment (on-set, mid, and off-set) for cepstral analysis. Results The cepstral analysis on the patients’ voices revealed no significant differences between the examination periods of all vowel phonations. However, analysis of the on-set fragment of the vowel /i/ revealed pathological characteristics in which the cepstral measurements of the voice were significantly lower after the operation than before the operation, with the cepstral measurements of the voice increasing further 6 weeks following surgery. Conclusion The results of the acoustic analysis on the on-set fragment of the vowel /i/ will be important data for characterizing the vocal changes during the perioperative period. This study contributes to future research on the mechanisms underlying changes in the voice of patients with a history of thyroid or neck surgery

Radiofrequency Ablation of Thyroid Nodules: Basic Principles and Clinical Application

Radiofrequency (RF) ablation has been gaining popularity as a minimally invasive treatment for benign thyroid nodules regardless of the extent of the solid component. RF ablation of benign nodules demonstrated volume reductions of 33–58% after one month and 51–85% after six months, while solving nodule-related clinical problems. RF ablation has recently shown positive short-term results for locoregional control as well as symptom improvement in patients with recurrent thyroid cancers. This paper reviews the basic physics, indications, patient preparation, devices, procedures, clinical results, and complications of RF ablation

Three-way Translocation of MLL/MLLT3, t(1;9;11)(p34.2;p22;q23), in a Pediatric Case of Acute Myeloid Leukemia

The chromosome band 11q23 is a common target region of chromosomal translocation in different types of leukemia, including infantile leukemia and therapy-related leukemia. The target gene at 11q23, MLL, is disrupted by the translocation and becomes fused to various translocation partners. We report a case of AML with a rare 3-way translocation involving chromosomes 1, 9, and 11: t(1;9;11)(p34.2;p22;q23). A 3-yr-old Korean girl presented with a 5-day history of fever. A diagnosis of AML was made on the basis of the morphological evaluation and immunophenotyping of bone marrow specimens. Flow cytometric immunophenotyping showed blasts positive for myeloid lineage markers and aberrant CD19 expression. Karyotypic analysis showed 46,XX,t(1;9;11)(p34.2;p22;q23) in 19 of the 20 cells analyzed. This abnormality was involved in MLL/MLLT3 rearrangement, which was confirmed by qualitative multiplex reverse transcription-PCR and interphase FISH. She achieved morphological and cytogenetic remission after 1 month of chemotherapy and remained event-free for 6 months. Four cases of t(1;9;11)(v;p22;q23) have been reported previously in a series that included cases with other 11q23 abnormalities, making it difficult to determine the distinctive clinical features associated with this abnormality. To our knowledge, this is the first description of t(1;9;11) with clinical and laboratory data, including the data for the involved genes, MLL/MLLT3

Methicillin-Resistant Staphylococcus aureus Blood Isolates Harboring a Novel Pseudo-staphylococcal Cassette Chromosome mec Element

The aim of this work was to assess a novel pseudo-staphylococcal cassette chromosome mec (ΨSCCmec) element in methicillin-resistant Staphylococcus aureus (MRSA) blood isolates. Community-associated MRSA E16SA093 and healthcare-associated MRSA F17SA003 isolates were recovered from the blood specimens of patients with S. aureus bacteremia in 2016 and in 2017, respectively. Antimicrobial susceptibility was determined via the disk diffusion method, and SCCmec typing was conducted by multiplex polymerase chain reaction. Whole genome sequencing was carried out by single molecule real-time long-read sequencing. Both isolates belonged to sequence type 72 and agr-type I, and they were negative for Panton-Valentine leukocidin and toxic shock syndrome toxin. The spa-types of E16SA093 and F17SA003 were t324 and t2460, respectively. They had a SCCmec IV-like element devoid of the cassette chromosome recombinase (ccr) gene complex, designated as ΨSCCmecE16SA093. The element was manufactured from SCCmec type IV and the deletion of the ccr gene complex and a 7.0- and 31.9-kb portion of each chromosome. The deficiency of the ccr gene complex in the SCCmec unit is likely resulting in mobility loss, which would be an adaptive evolutionary mechanism. The dissemination of this clone should be monitored closely

Low-Power Complementary Inverter Based on Graphene/Carbon-Nanotube and Graphene/MoS₂ Barristors

The recent report of a p-type graphene(Gr)/carbon-nanotube(CNT) barristor facilitates the application of graphene barristors in the fabrication of complementary logic devices. Here, a complementary inverter is presented that combines a p-type Gr/CNT barristor with a n-type Gr/MoS2 barristor, and its characteristics are reported. A sub-nW (~0.2 nW) low-power inverter is demonstrated with a moderate gain of 2.5 at an equivalent oxide thickness (EOT) of ~15 nm. Compared to inverters based on field-effect transistors, the sub-nW power consumption was achieved at a much larger EOT, which was attributed to the excellent switching characteristics of Gr barristors

Spinal cord stimulator malfunction caused by radiofrequency neuroablation -A case report-

The implantation of spinal cord stimulators (SCSs) to treat chronic intractable pain is steadily increasing. And there is an increased likelihood of instances where other therapies or procedures are found to interfere with SCS function, which in turn may result in pain. Since SCS utilize electric impulses as well as magnets, special considerations need for patients with a SCS in situ who require these procedures. The present report describes a case where radiofrequency (RF) ablation of the third occipital nerve resulted in spontaneous activation of a cervical SCS device