Future N deposition and precipitation changes will be beneficial for the growth of Haloxylon ammodendron in Gurbantunggut Desert, northwest China.

Evaluation of precipitation and nitrogen (N) deposition in desert ecosystems helps to elucidate the reaction of desert ecosystems to future environmental changes. An in-situ field experiment was established to examine the influence of a long-term enhanced precipitation and N deposition on the photosynthetic traits and physiological characteristics of Haloxylon ammodendron in the Gurbantunggut Desert, northwest China, throughout the growing season in 2014-2016. Results showed a significant interaction between precipitation and N applications. Increased precipitation and N deposition and their coupling could significantly improve photosynthetic capacity, alter the variability in amplitude of water potential and change the content of substances regulating osmotic pressure in H. ammodendron. According to the comprehensive evaluation of H. ammodendron's adaptability using six different water and N coupling models, a combination of a 30% increase in precipitation and a 30 kg N ha-1 yr-1 addition in nitrogen deposition, or the addition of N at a concentration of 60 kg N ha-1 yr-1 with natural precipitation were beneficial to H. ammodendron growth and development. Hence, changes in the future global environment can be anticipated to be beneficial to H. ammodendron growth.

The effects of neuromuscular blockade on operating conditions during general anesthesia for spinal surgery.

BACKGROUND: Muscle relaxants are prescribed routinely for patients undergoing general anesthesia, but the requirement for paralysis in spinal surgery is unclear. This study compared the operating conditions of general anesthesia with and without a muscle relaxant on spinal surgery patients. METHODS: Eighty-six adults who underwent elective spinal surgery were randomly assigned to a relaxant group (group R) or a no-relaxant group (group NR). All patients were induced with intravenous midazolam (0.05 mg/kg), fentanyl (4 µg/kg), propofol (1.0 mg/kg), and succinylcholine (2 mg/kg) and then atracurium was used in group R but not in group NR. The operating conditions, including muscle tone, body movements, airway pressure, anesthetics consumption, eye-opening time, extubation time, and the Observer's Assessment of the Alertness/Sedation (OAA/S) score 20 minutes after the extubation were compared between the 2 groups. RESULTS: The operating conditions including muscle tone scales, body movements, and airway pressure did not differ between the 2 groups. Eye-opening time (9.35±2.34 vs. 11.02±2.50 min; P=0.002) and extubation time (13.95±3.41 vs. 16.72±3.67 min; P=0.001) were shorter in group NR than in group R. The BIS score at extubation (87.2±5.0 vs. 83.3±5.7; P=0.001) and the OAA/S score 20 minutes after extubation (5 [3 to 5] vs. 4 [3 to 5]; P=0.005) were significantly higher in group NR than in group R. Propofol consumption was higher in group NR than in group R (4206.10±415.80 vs. 3900.60±365.40 µg/kg, respectively; P=0.001). CONCLUSIONS: General anesthesia without muscle relaxant provides similar working conditions to those observed with muscle relaxant, and it is associated with earlier eye opening and extubation and higher level of consciousness on emergence from spinal surgery.