Low-noise slot antenna SIS mixers

We describe quasi-optical SIS mixers operating in the submillimeter band (500-750 GHz) which have very low noise, around 5 h/spl nu//k/sub B/ for the double-sideband receiver noise temperature. The mixers use a twin-slot antenna, Nb/Al-Oxide/Nb tunnel junctions fabricated with optical lithography, a two-junction tuning circuit, and a silicon hyperhemispherical lens with a novel antireflection coating to optimize the optical efficiency. We have flown a submillimeter receiver using these mixers on the Kuiper Airborne Observatory, and have detected a transition of H/sub 2//sup 18/O at 745 GHz. This directly confirms that SIS junctions are capable of low-noise mixing above the gap frequency

Effect of high intensity interval training on elite athletes' antioxidant status

Objective: The effects of high intensity interval exercises on antioxidant defense system are not clear. Since there is an evident lack of studies focused on oxidative stress experienced following combat sports and high intensity interval training, we investigated oxidative stress markers (malondialdehyde [MDA], catalase [CAT], glutathione peroxidase [GPX], superoxide dismutase [SOD]) by completing high intensity interval training program (HIITP) and following International Muay Thai Championship (IMTC). Methods: The study was carried out on 21 elite players (15 males and six females) who had regular exercising and training habits. The participants were subjected to a daily 3-hour HIITP during brief training camp (10-day) before IMTC. They were instructed to maintain their normal dietary practices throughout the camp and during the study to take no antioxidant containing vitamin tablets. Results: There was a significant increase in MDA levels and significant decrease in CAT activities of players (P<. 0.05). The differences in SOD and GPX activities were not significant. Conclusion: These results suggested that high intensity interval training and competition could affect the oxidative status of Muay Thai (MT) athletes. © 2012 Elsevier Masson SAS

Submillimeter spectroscopy of interstellar hydrides

We discuss airborne observations of rotational transitions of various hydride molecules in the interstellar medium, including H_2^(18)O and HCI. The detection of these transitions is now feasible with a new, sensitive submillimeter receiver which has been developed for the NASA Kuiper Airborne Observatory (KAO) over the past several years

An innovative tailored instructional design for computer programming courses in engineering

Industry 4.0 and 5.0 topics are emerging fields and have seen rising demand recently. There is a critical need, on the other hand, for improved methods of instructing programming languages since a growing lack of student motivation during the pandemic has had a deleterious influence on the education of programmers. In this context, online/hybrid computer programming courses must be addressed with innovative solutions to support the field with well-educated professionals. In this paper, we present a case study to propose an innovative tailored instructional design for the online/hybrid learning environments for programming courses in engineering faculties. To develop the instructional design, the Kemp Instructional Design Model was followed. The instructional design is a result of the main outputs of the RECOM “Redesigning Introductory Computer Programming Using Innovative Online Modules” project, which aims to bridge the gap between the existing course design in programming courses and the needs of "Covid” and “post-Covid” generation students

Single session endoscopic management of intrinsic ureteropelvic junction obstruction and concomitant renal stone disease in a child: a case report

BACKGROUND: Percutaneous nephrolithotomy is a well known therapeutic modality for stone diseases of childhood. Antegrade and retrograde endopyelotomies are also well defined options of treatment for secondary ureteropelvic junction obstruction. Yet there are few reports regarding endoscopic therapy of intrinsic ureteropelvic junction obstruction. To our knowledge, there exist only a few reports of endosurgical treatment of children with stone disease and with concomitant intrinsic ureteropelvic junction obstruction, in the literature. CASE PRESENTATION: We present the endoscopic management of stone disease and concomitant intrinsic ureteropelvic junction obstruction of a child in one session. CONCLUSION: Percutaneous nephrolithotomy and antegrade endopyelotomy is combined safely with successful outcome in a child

Uridine-derived ribose fuels glucose-restricted pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDA) is a lethal disease notoriously resistant to therapy1,2. This is mediated in part by a complex tumour microenvironment3, low vascularity4, and metabolic aberrations5,6. Although altered metabolism drives tumour progression, the spectrum of metabolites used as nutrients by PDA remains largely unknown. Here we identified uridine as a fuel for PDA in glucose-deprived conditions by assessing how more than 175 metabolites impacted metabolic activity in 21 pancreatic cell lines under nutrient restriction. Uridine utilization strongly correlated with the expression of uridine phosphorylase 1 (UPP1), which we demonstrate liberates uridine-derived ribose to fuel central carbon metabolism and thereby support redox balance, survival and proliferation in glucose-restricted PDA cells. In PDA, UPP1 is regulated by KRAS-MAPK signalling and is augmented by nutrient restriction. Consistently, tumours expressed high UPP1 compared with non-tumoural tissues, and UPP1 expression correlated with poor survival in cohorts of patients with PDA. Uridine is available in the tumour microenvironment, and we demonstrated that uridine-derived ribose is actively catabolized in tumours. Finally, UPP1 deletion restricted the ability of PDA cells to use uridine and blunted tumour growth in immunocompetent mouse models. Our data identify uridine utilization as an important compensatory metabolic process in nutrient-deprived PDA cells, suggesting a novel metabolic axis for PDA therapy