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In order to explore the thermal decomposition and combustion performances of zirconium powder (Zr) with high-energy oxidant composite, the thermal decomposition behavior, combustion heat and ignition combustion process of four kinds of energetic materials (EMs) of AP, CL-20, HMX, DAP-4 and Zr/EMs samples were compared and analyzed by using differential scanning calorimetry, automatic calorimetry and self-built combustion experimental system. Some combustion products were collected and characterized. The combustion mechanism of Zr/DAP-4 was analyzed. Results show that the thermal stability and combustion heat release of DAP-4 are better than that of the other three EMs samples. The addition of Zr leads to a higher combustion heat and a lower fa value of the sample, the thermal decomposition temperature remains at 373.8°C, and the combustion performance is better than that of pure DAP-4. Compared with the thermal decomposition of Zr/CL-20 and Zr/ HMX, Zr/DAP-4 has a higher initial decomposition temperature and peak temperature, a lower apparent activation energy fa (138. 7 kj/mol), and a higher combustion heat (17 134J/g). The entire combustion time of Zr/DAP-4 composite is only 170ms, indicating a rapid and intense combustion reaction and its flame intensity is also superior to the other three samples. The combustion products of Zr/DAP-4 include solid products such as ZrO2 and gas products such as H2O and HCI. Zr/DAP-4 composite energetic material has higher energy characteristics and better combustion performances, which make it has great potential for application in the formulation design of propellants. [ABSTRACT FROM AUTHOR]

By the method of pitfall trapping, an investigation was conducted on the diversity of ground-dwelling ants in a lac plantation in Yayi Town of Mojiang County, Yunnan Province of Southwest China in December 2009-May 2010, aimed to understand the effects of lac insect honey- dew on the diversity of ground-dwelling ants. The presence or absence of lac insect honeydew and its dynamics all affected the species composition, abundance, and diversity of ground-dwelling ants. In the lac plantation with lac insect hosting, a total of 4953 ant individuals were collected, belonging to 34 species, 23 genera, and 5 subfamilies of Formicidae; whereas in the lac plantation without lac insect hosting, a total of 2416 ant individuals were collected, belonging to 30 species, 20 genera, and 5 subfamilies of Formicidae. The relative abundance, species richness (S), and ACE index in the lac plantation with lac insect hosting were higher than those in the lac plantation without lac insect hosting, and the common species and indicator species of ground-dwelling ants in the lac plantation with lac insect hosting differed from those in the lac plantation without lac insect hosting, suggesting that lac insect hosting altered the community structure of ground-dwelling ants. The adult lac insects excreted larger quantity of honeydew than the larval lac insects, and the relative abundance, S, and ACE index of ground-dwelling ants were higher at the adult stage than at the larval stage of lac insects. The common species and indicator species of ground-dwelling ants also had great differences between the two stages of lac insects. [ABSTRACT FROM AUTHOR]

From October 2008 to May 2010, an investigation was made in a lac plantation in Yayi region of Mojiang County, Yunnan Province, China, aimed to understand the behavior of the monopolization of honeydew sources by ant Crematogaster macaoensis, and its effects on the sex ratio, mortality, fecundity, and lac production of Yunnan lac insect Kerria yunnanensis. The results showed that C. macaoensis fed and monopolized the honeydews around the clock during the whole life cycle of K. yunnanensis on the stick-lac, and the average number of visiting C. macaoensis ranged from 16.8±2.3 to 39.3±10.0 per 10 cm length of the stick-lac. C. macaoensis constructed shelters to prevent other animals from visiting the lac insect. C. macaoensis monopolization reduced the lac production of individual K. yunnanensi significantly, but had no significant effects on the lac production of whole lac insect colony. In addition, C. macaoensis monopolization reduced the mortality of K. yunnanensis significantly, and increased the percentage of K. yunnanensis females and the adult female fecundity. It was concluded that ant monopolization of the lac insect honeydew seemed to be beneficial to the lac production by the Yunnan lac insect. [ABSTRACT FROM AUTHOR]

order to reveal the coexistence mechanism of ant community in lac plantation, an investigation was made on the ant community composition and the ability of ant species in discovering and holding food resources in a lac plantation in Yayi Town of Mojiang County, Yunnan Province, with the relationships between ant body size and its ability of finding food under habitat heterogeneity probed. There were six dominant ant species in the plantation, i. e. , Tetraponera allaborans (Walker), Crematogaster macaoensis Wheeler, Crematogaster ferrarii Emery, Dolichoderus thoracicus (Smith), Polyrhachis proxima Roger, and Camponotus parius Emery. The hind leg length (y) of the six ant species increased allometrically with their head width (x), and the regression equation was y =0-56+1-02x+5-97x2 -10-85x3. Different ant species had significant differences in their actual and relative frequency in discovering food resources in different habitats, but habitat type had no significant effects on the actual frequency in holding food resources by the ant species. The ant species with bigger head width and bigger body size index could discover more food resources in simple habitat. In contrast, the ant species with smaller head width, shorter hind leg length, and smaller body size index could discover more food resources in complex habitat. The heterogeneity of habitat caused the coexistence of ants: the smaller ant species lived in complex habitat, while the larger ones lived in simple habitat. In addition, numerically dominant ant species were unable to possess all resources, and thereby, could provide the opportunity to other ant species for resources acquisition, making the species coexistence come true. [ABSTRACT FROM AUTHOR]

Background: Enterocutaneous fistula (ECF) is an abnormal connection between the gastrointestinal tract and the skin. ECF can lead to massive body fluid loss, hypercatabolism, and malnutrition. Therefore, nutritional support plays a crucial role in managing ECFs and promoting the healing of fistulas. For nutritional support, enteral nutrition (EN) is the preferred method when gastrointestinal function is recovering. Currently, various EN approaches have been applied for different anatomical positions of the ECF. However, the effectiveness of administering EN support for treating lower ECFs still needs further exploration and improvement., Case Summary: We present the case of a 46-year-old male who underwent gastrointestinal stromal tumour resection. Six days after the surgery, the patient presented with fever, fatigue, severe upper abdominal pain, and septic shock. Subsequently, lower ECFs were diagnosed through laboratory and imaging examinations. In addition to symptomatic treatment for homeostasis, total parenteral nutrition support was administered in the first 72 h due to dysfunction of the intestine. After that, we gradually provided EN support through the intestinal obstruction catheter in consideration of the specific anatomic position of the fistula instead of using the nasal jejunal tube. Ultimately, the patient could receive optimal EN support via the catheter, and no complications were found during the treatment., Conclusion: Nutritional support is a crucial element in ECF management, and intestinal obstruction catheters could be used for early EN administration., Competing Interests: Conflict-of-interest statement: The authors declare that they have no conflicts interest to disclose., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

By the method of pitfall trapping, an investigation was conducted on the diversity of ground-dwelling ants in a lac plantation in Yayi Town of Mojiang County, Yunnan Province of Southwest China in December 2009-May 2010, aimed to understand the effects of lac insect honeydew on the diversity of ground-dwelling ants. The presence or absence of lac insect honeydew and its dynamics all affected the species composition, abundance, and diversity of ground-dwelling ants. In the lac plantation with lac insect hosting, a total of 4953 ant individuals were collected, belonging to 34 species, 23 genera, and 5 subfamilies of Formicidae; whereas in the lac plantation without lac insect hosting, a total of 2416 ant individuals were collected, belonging to 30 species, 20 genera, and 5 subfamilies of Formicidae. The relative abundance, species richness (S), and ACE index in the lac plantation with lac insect hosting were higher than those in the lac plantation without lac insect hosting, and the common species and indicator species of ground-dwelling ants in the lac plantation with lac insect hosting differed from those in the lac plantation without lac insect hosting, suggesting that lac insect hosting altered the community structure of ground-dwelling ants. The adult lac insects excreted larger quantity of honeydew than the larval lac insects, and the relative abundance, S, and ACE index of ground-dwelling ants were higher at the adult stage than at the larval stage of lac insects. The common species and indicator species of ground-dwelling ants also had great differences between the two stages of lac insects.

From October 2008 to May 2010, an investigation was made in a lac plantation in Yayi region of Mojiang County, Yunnan Province, China, aimed to understand the behavior of the monopolization of honeydew sources by ant Crematogaster macaoensis, and its effects on the sex ratio, mortality, fecundity, and lac production of Yunnan lac insect Kerria yunnanensis. The results showed that C. macaoensis fed and monopolized the honeydews around the clock during the whole life cycle of K. yunnanensis on the stick-lac, and the average number of visiting C. macaoensis ranged from 16.8 +/- 2.3 to 39.3 +/- 10.0 per 10 cm length of the stick-lac. C. macaoensis constructed shelters to prevent other animals from visiting the lac insect. C. macaoensis monopolization reduced the lac production of individual K. yunnanensi significantly, but had no significant effects on the lac production of whole lac insect colony. In addition, C. macaoensis monopolization reduced the mortality of K. yunnanensis significantly, and increased the percentage of K. yunnanensis females and the adult female fecundity. It was concluded that ant monopolization of the lac insect honeydew seemed to be beneficial to the lac production by the Yunnan lac insect.

In order to reveal the coexistence mechanism of ant community in lac plantation, an investigation was made on the ant community composition and the ability of ant species in discovering and holding food resources in a lac plantation in Yayi Town of Mojiang County, Yunnan Province, with the relationships between ant body size and its ability of finding food under habitat heterogeneity probed. There were six dominant ant species in the plantation, i. e., Tetraponera allaborans (Walker), Crematogaster macaoensis Wheeler, Crematogasterferrarii Emery, Dolichoderus thoracicus (Smith), Polyrhachis proxima Roger, and Camponotus parius Emery. The hind leg length (y) of the six ant species increased allometrically with their head width (x), and the regression equation was y = 0.56 + 1.02x + 5.97x2 - 10.85x3. Different ant species had significant differences in their actual and relative frequency in discovering food resources in different habitats, but habitat type had no significant effects on the actual frequency in holding food resources by the ant species. The ant species with bigger head width and bigger body size index could discover more food resources in simple habitat. In contrast, the ant species with smaller head width, shorter hind leg length, and smaller body size index could discover more food resources in complex habitat. The heterogeneity of habitat caused the coexistence of ants: the smaller ant species lived in complex habitat, while the larger ones lived in simple habitat. In addition, numerically dominant ant species were unable to possess all resources, and thereby, could provide the opportunity to other ant species for resources acquisition, making the species coexistence come true.