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High temperature frequently occurs during rice's early grain-filling period in the south of China, negatively affecting rice yield and quality and posing a major threat to local rice production. This experiment researched the influence of 3.5 °C warming during the first 20 grain-filling days on rice yield and quality and emphatically investigated the effects of the low-broadcast nitrogen fertilizer application level (LBN), high-broadcast nitrogen fertilizer application level (HBN) and foliar nitrogen fertilizer application (FN) at heading on the rice organ temperature, leaf photosynthesis, chlorophyll fluorescence, yield and grain quality, pasting and thermal properties under high temperature in 2020 and 2022, with a widely planted japonica rice variety, "Wuyunjing31", in order to explore the practical mitigation measures for reducing the adverse impact of high temperature on rice productivity. The results showed that high temperatures during grain filling increased the rice plant temperature, damaged the chlorophyll fluorescence system and decreased the net photosynthesis rate. This led to a decline in the seed-setting rate and grain weight, resulting in a 7.0% and 13.9% yield loss in 2020 and 2022, respectively. In addition, high temperature caused a decline in the head rice rate and an increase in chalk occurrence and pasting temperature, thereby deteriorating rice grain quality. Under high temperatures, HBN enhanced the rice yield by 3.6% and 13.0% in 2020 and 2022, respectively, while FN enhanced the rice yield by 11.5% in 2022. The increase in yield was linked to the increased seed-setting rate and 1000-grain weight. LBN did not significantly affect the rice yield under high temperatures. The positive effects of nitrogen fertilizer measures on rice yield were associated with their role in lowering plant temperature and protection against the damage to the chlorophyll fluorescence system. All three nitrogen application measures generally improved rice milling quality and appearance quality under high temperature, with HBN generally showing the greatest impact. Under high temperature, LBN and FN tended to make the texture of cooked rice softer due to the decreased consistency, retrogradation enthalpy and retrogradation percentage, and this was closely associated with the decline in amylose content. In summary, nitrogen supplementation at the heading could efficiently mitigate the adverse impact of high temperature during the early grain-filling period on rice yield and quality. [ABSTRACT FROM AUTHOR]

Oil and gas reservoirs in volcanic rocks are a particular type of unconventional reservoir and present unique challenges for exploration and production engineers. To help the oil industry understand volcanic reservoirs and solutions to complex development problems, we reviewed their key engineering technologies as well as their geological characteristics. The distinctive geological characteristics of volcanic hydrocarbon reservoirs are strong heterogeneity, low porosity and permeability, complex fracture systems, etc. The volcanic reservoir rock types in order of hydrocarbon abundance are basalt (38.5%), andesite (15.9%), volcaniclastic (12.1%), and rhyolite (11.5%). The porosity ranges from 0.1 to 70%, and permeability ranges from 0.0007 to 762 md. In some commercially developed volcanic reservoirs of China, the average porosity is 7.7–13%; the average permeability is 0.41–3.4 md. Engineers have applied a variety of adapted technologies to produce volcanic reservoir economically. Horizontal wells can increase production and reserves by 4–6 times those of vertical wells, and longer wells are preferred. Specialized hydraulic fracturing techniques are suggested, including small or mixed proppant size, second HF treatment after proppant slugging, high-viscosity frac fluid with high-temperature resistance, special fluid loss reducer, high pump pressure, Extreme Overbalance Perforating, limited-entry fracturing, matrix acidizing, etc. Water control measures include producing below critical rates, partial perforation or penetration, controlling hydraulic fracture height, using horizontal wells, implementing complete cementing job, etc. Well productivity evaluation should be conducted to understand well performance and appropriately allocate production rates among wells, using the modified AOF method and other productivity prediction models considering breakdown fracture gradient, gas slippage effect, non-Darcy effect, etc. Well sites need to be selected based on recognizing profitable lithologies, lithofacies, high porosity and permeability, relatively developed fracture systems, thick net pay zones, etc. The critical questions for the industry are how to enhance volcanic reservoir recovery with more efficient and economic hydraulic fracturing and water control techniques. This is one of the first papers systematically summarizing the engineering technologies and unique solutions to develop volcanic reservoirs. Further and more complete reviews can be carried out in the future, and more novel and effective techniques can be explored and tested in the field. [ABSTRACT FROM AUTHOR]

Objective: This study examined the relationships between skeletal deformities and the pharyngeal airway of patients with nonsyndromic unilateral cleft lip and palate (UCLP). Design: Retrospective study. Setting: Orthodontics and Oral and Maxillofacial Surgery Departments in the Affiliated Hospital of Stomatology, Nanjing Medical University, China. Patients, Participants: The sample comprised 30 nonsyndromic UCLP patients and 30 healthy controls. Each group has 23 males and 7 females. Interventions: All cone-beam computed tomography images were obtained with the participant in the standard supine position and asked to bite with intercuspal position without swallowing or moving their heads and tongues during scanning. Main Outcome Measure(s): SNA, SNB, ANB, anterior cranial base, Wits appraisal, maxillary length (PTM-ANS || FH), maxillary position (S-PTM || FH), mandibular length (Go-Pog || MP), FMA, posterior face height, anterior face height, Posterior-Anterior face height, lower face height, pharyngeal airway volumes, and areas were evaluated by Dolphin imaging software. Results: The UCLP group showed significantly decreased SNA, SNB, ANB, PTM-ANS || FH, S-PTM || FH, P-A Face Height compared with the controls. However, the airway volumes and areas showed no significant difference between 2 groups. The total airway volume and minimum cross-sectional area in UCLP patients were related to the Go-Pog || MP and FMA. Conclusions: Patients with UCLP have both the maxillary and mandibular deficiencies in the sagittal dimension. Both the sagittal and vertical relationships of the jaw might affect the airway volume and area. However, no significant difference was detected in airway volume and area in UCLP patients when compared with the controls. [ABSTRACT FROM AUTHOR]

Objective: This study examined the relationships between skeletal deformities and the pharyngeal airway of patients with nonsyndromic unilateral cleft lip and palate (UCLP)., Design: Retrospective study., Setting: Orthodontics and Oral and Maxillofacial Surgery Departments in the Affiliated Hospital of Stomatology, Nanjing Medical University, China., Patients, Participants: The sample comprised 30 nonsyndromic UCLP patients and 30 healthy controls. Each group has 23 males and 7 females., Interventions: All cone-beam computed tomography images were obtained with the participant in the standard supine position and asked to bite with intercuspal position without swallowing or moving their heads and tongues during scanning., Main Outcome Measure(s): SNA, SNB, ANB, anterior cranial base, Wits appraisal, maxillary length (PTM-ANS || FH), maxillary position (S-PTM || FH), mandibular length (Go-Pog || MP), FMA, posterior face height, anterior face height, Posterior-Anterior face height, lower face height, pharyngeal airway volumes, and areas were evaluated by Dolphin imaging software., Results: The UCLP group showed significantly decreased SNA, SNB, ANB, PTM-ANS || FH, S-PTM || FH, P-A Face Height compared with the controls. However, the airway volumes and areas showed no significant difference between 2 groups. The total airway volume and minimum cross-sectional area in UCLP patients were related to the Go-Pog || MP and FMA., Conclusions: Patients with UCLP have both the maxillary and mandibular deficiencies in the sagittal dimension. Both the sagittal and vertical relationships of the jaw might affect the airway volume and area. However, no significant difference was detected in airway volume and area in UCLP patients when compared with the controls.