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The orthodontic management of patients with Class III malocclusion poses numerous treatment challenges. Various removable, fixed, orthopedic, and myofunctional appliances have been recommended for its correction. The Reverse Twin Block is a removable appliance which has been used for the early management of such cases. A 10‐year‐old female with no significant medical and family history presented with the chief complaint of forward placement of lower front teeth on biting. Extraoral examination revealed a mesoprosopic face, a prominent lower lip, and a shallow mentolabial sulcus. Facial profile was straight at rest and concave at maximum intercuspation. Intraoral examination revealed a Class III incisor relationship with premature contact between 21 and 31, causing a forward path of closure of the mandible. The patient had a reverse overjet of 2 mm, an overbite of 5 mm, and a bilateral Super‐class I molar relationship at maximum intercuspation. Lateral cephalogram analysis revealed a mild skeletal class III denture base (ANB = 0°, Wits = −4 mm) due to a prognathic mandible (SNB = 82°). The treatment objectives included elimination of the premature contact, establishment of a positive overjet, and improvement of the facial profile. A Reverse Twin Block appliance was planned and prescribed for full‐time wear for 8 months. At the end of treatment, the patient had a Class I incisor relationship, straight facial profile, Class I molar relationship on the left side, and Super‐class I molar relationship on the right side. The Reverse Twin Block is a simple and well‐tolerated appliance that can effectively correct developing Class III malocclusion in carefully selected cases. [ABSTRACT FROM AUTHOR]

This paper quantifies experimentally the effect of ventilation in diesel pool fire (d = 0.6 m) in a cubical compartment of 64 m3 with ventilation opening factor in range of 0.088–2.828 m 5 / 2 . The work is addressed to fire safety in nuclear power plant in which ventilated enclosure are frequently used for chemical processing of flammable fuels. In present work, fuel mass loss rate, global CO concentration, global CO/CO2 yield, flame temperature, global equivalence ratio, doorway temperature with velocity profile, and heat flux are measured to predict the effect of ventilation in compartment fire. Ventilation with test 3 is noted as critical opening i.e. after that mass loss rate suddenly decreased. It is also observed that compartment fire is affected more by varying door height rather than varying door width. Unpredictably, global CO emission are obtained nearly the same regardless of doorway opening. Combustion efficiency is found to be in range of 0.39–0.93. Results showed that reduction in ventilation results in oscillating flame behavior and increase in upper layer gas temperature. Present data correlated well under thermal scaling analysis. The results shown in present work can be used as an input to fire hazard analysis in nuclear power plants. [ABSTRACT FROM AUTHOR]

Reaction conditions for the CC cross-coupling of O6-alkyl-2-bromo- and 2-chloroinosine derivatives with aryl-, hetaryl-, and alkylboronic acids were studied. Optimization experiments with silyl-protected 2-bromo- O6-methylinosine led to the identification of [PdCl2(dcpf)]/K3PO4 in 1,4-dioxane as the best conditions for these reactions (dcpf=1,1′-bis(dicyclohexylphosphino)ferrocene). Attempted O6-demethylation, as well as the replacement of the C-6 methoxy group by amines, was unsuccessful, which led to the consideration of Pd-cleavable groups such that CC cross-coupling and O6-deprotection could be accomplished in a single step. Thus, inosine 2-chloro- O6-allylinosine was chosen as the substrate and, after re-evaluation of the cross-coupling conditions with 2-chloro- O6-methylinosine as a model substrate, one-step CC cross-coupling/deprotection reactions were performed with the O6-allyl analogue. These reactions are the first such examples of a one-pot procedure for the modification and deprotection of purine nucleosides under CC cross-coupling conditions. [ABSTRACT FROM AUTHOR]