Interpreting Highly Variable Indoor PM2.5 in Rural North China Using Machine Learning.

Household air pollution associated with solid fuel use is a long-standing public concern. The global population mainly using solid fuels for cooking remains large. Besides cooking, large amounts of coal and biomass fuels are burned for space heating during cold seasons in many regions. In this study, a wintertime multiple-region field campaign was carried out in north China to evaluate indoor PM2.5 variations. With hourly resolved data from ∼1600 households, key influencing factors of indoor PM2.5 were identified from a machine learning approach, and a random forest regression (RFR) model was further developed to quantitatively assess the impacts of household energy transition on indoor PM2.5. The indoor PM2.5 concentration averaged at 120 µg/m3 but ranged from 16 to ∼400 µg/m3. Indoor PM2.5 was ∼60% lower in families using clean heating approaches compared to those burning traditional coal or biomass fuels. The RFR model had a good performance (R2 = 0.85), and the interpretation was consistent with the field observation. A transition to clean coals or biomass pellets can reduce indoor PM2.5 by 20%, and further switching to clean modern energies would reduce it an additional 30%, suggesting many significant benefits in promoting clean transitions in household heating activities.

Identification of Factors Determining Household PM2.5 Variations at Regional Scale and Their Implications for Pollution Mitigation.

Indoor PM2.5, particulate matter no more than 2.5 µm in aerodynamic equivalent diameter, has very high spatiotemporal variabilities; and exploring the key factors influencing the variabilities is critical for purifying air and protecting human health. Here, we conducted a longer-term field monitoring campaign using low-cost sensors and evaluated inter- and intra-household PM2.5 variations in rural areas where energy or stove stacking is common. Household PM2.5 varied largely across different homes but also within households. Using generalized linear models and dominance analysis, we estimated that outdoor PM2.5 explained 19% of the intrahousehold variation in indoor daily PM2.5, whereas factors like the outdoor temperature and indoor-outdoor temperature difference that was associated with energy use directly or indirectly, explained 26% of the temporal variation. Inter-household variation was lower than intrahousehold variation. The inter-household variation was strongly associated with distinct internal sources, with energy-use-associated factors explaining 35% of the variation. The statistical source apportionment model estimated that solid fuel burning for heating contributed an average of 31%-55% of PM2.5 annually, whereas the contribution of sources originating from the outdoors was ≤10%. By replacing raw biomass or coal with biomass pellets in gasifier burners for heating, indoor PM2.5 could be significantly reduced and indoor temperature substantially increased, providing thermal comforts in addition to improved air quality.

Uncut Roux-en-Y might reduce the rate of reflux gastritis after radical distal gastrectomy: An evidence mapping from a systematic review.

BACKGROUND: To evaluate the efficacy, safety, technical feasibility, and effect of reducing the incidence of reflux gastritis from uncut Roux-en-Y (URY) reconstruction after radical distal gastrectomy (RDG) for gastric cancer. METHODS: A literature search was conducted in PubMed, EMBASE, Web of Science, the Cochrane Library, Chinese National Knowledge Infrastructure, and WanFang databases until June 30, 2020, to identify studies comparing URY reconstruction with other gastrointestinal tract reconstruction methods after RDG. The Newcastle-Ottawa Scale (NOS) and the Cochrane Collaboration's risk for bias assessment tool were used to assess the risk of bias. The study was performed using review manager RevMan 5.3.0 software. RESULTS: A total of 35 original studies (six randomized clinical trials (RCTs) and 29 cohort studies) were included in this analysis with a total of 4100 patients. For reflux gastritis, URY anastomosis was significantly superior to the other four types of anastomoses (Billroth-I (odds ratio (OR) = 0.16 [0.10, 0.27], P < 0.00001); Billroth-II (OR = 0.32 [0.20, 0.51], P < 0.00001); Billroth-II with Braun (OR = 0.14 [0.007, 0.26], P < 0.00001), and Roux-en-Y (OR = 0.59 [0.38, 0.91], P = 0.02)). Furthermore, URY anastomosis was better than Billroth-II with Braun (OR = 0.07, 95%confidence interval (CI): [0.02, 0.28], P = 0.0001) and Billroth-II (OR = 0.14, 95%CI: [0.09, 0.24], P < 0.00001) anastomoses for preventing bile reflux. In addition, for anastomotic leakage, URY anastomosis was significantly superior to Roux-en-Y (OR = 0.34, 95%CI: [0.13, 0.87], P = 0.02) anastomosis, and no statistically significant difference between URY and the other three reconstruction methods was found. The postoperative hospital stay of patients receiving URY anastomosis was substantially shorter than those receiving Billroth-II with Braun (MD: 2.84, 95%CI: [-3.16, -1.80], P < 0.00001), Bollroth-II (MD: 1.23, 95%CI: [-2.10, -0.37], P = 0.005) and Roux-en-Y (MD: 1.98, 95%CI: [-2.17, -1.78], P < 0.00001) anastomoses. CONCLUSION: URY reconstruction significantly reduce the rate of reflux gastritis after RDG, and it was a more favorable reconstruction method after RDG for its operative simplicity, safety, and reduced postoperative complications especially in Roux-en-Y stasis syndrome. Large sample size cohort studies and well-designed RCTs are needed for further confirmation of our findings. OTHER: This work was supported by the National Nature Science Foundation of China (No.81871962), Industry-University-Research Innovation Fund in the Ministry of Education of the People's Republic of China (No. 2018A01013) and the Autonomous Intelligent Unmanned System (No. 62088101). This study was registered with PROSPERO (CRD42020200906).

[Application of intravenous injection of tranexamic acid combined with local use of tranexamic acid cocktail in intertrochanteric fracture fixation].

OBJECTIVE: To explore the efficacy and safety of intravenous injection of tranexamic acid (TXA) combined with local use of TXA cocktail in intertrochanteric fracture fixation with proximal femoral nail antirotation (PFNA). METHODS: Patients with intertrochanteric fractures who underwent close reduction and internal fixation with PFNA between February 2018 and March 2019 were enrolled in the study. Among them, 45 patients who met the selection criteria were included in the study and randomly allocated into 3 groups ( n=15). The patients in group A were not received TXA during perioperative period. The patients were intravenously injected of 1.0 g TXA before operation in group B and combined with local use of TXA cocktail during operation in group C. There was no significant difference in the age, gender, body mass index, fracture classification, disease duration, and complications between groups ( P>0.05). The perioperative blood loss and blood transfusion rate, the visual analogue scale (VAS) score before operation and at 12, 24, and 48 hours after operation, the levels of prostaglandin E2 (PGE2) and bradykinin (BK) before operation and at 1 and 3 days after operation, postoperative complications, and the maximum amplitude (MA) of thromboelastogram were recorded and compared between groups. RESULTS: The total blood loss, hidden blood loss, and visible blood loss were significantly lower in groups B and C than those in group A ( P<0.05), and the total blood loss and hidden blood loss were significantly lower in group C than those in group B ( P<0.05). There was no significant difference in the blood transfusion rate, preoperative VAS scores and the levels of PGE2 and BK between groups ( P>0.05). The postoperative VAS scores and the levels of PGE2 and BK were significantly lower in group C than in groups A and B ( P<0.05). There was no significant difference in pre- and post-operative MA of thromboelastogram between groups ( P>0.05). The incidences of postoperative complications were 33.33% (5/15), 20.00% (3/15), and 13.33% (2/15) in groups A, B, and C, respectively, with no significant difference between groups ( χ 2=1.721, P=0.550). CONCLUSION: For intertrochanteric fractures, application of intravenous injection of TXA combined with local use of TXA cocktail in PFNA fixation can reduce perioperative blood loss, relieve pain after operation, and do not increase the risk of complications.

[Ilizarov technique combined with flap instant expansion technique for the treatment of the tibia deformity with skin contracture at one stage].

OBJECTIVE: To discusses the necessity and methods of replantation for complete amputation of finger composite lateral tissue. METHODS: From March 2012 to April 2015, 62 cases of complete amputated finger lateral tissue for various causes were retrospectively analyzed, including 34 males and 28 females with an average age of 29.1 years old ranging from 17 to 52 years old, involved 27 cases of thumb, index finger in 15 cases, 13 cases of middle finger, ring finger in 8 cases, 2 cases of the little finger, 2 fingers were injured in 3 cases, 14 cases involving the distal interphalangeal joint. The time from injury to treatment was 30 min to 2 hour with an average of 1 hour. The appearance of the fingers, finger tip sensation and the recovery of the functional of the patients were followed up and observed. RESULTS: Of 62 cases, 58 cases survived, the survival time was 3 to 15 months with an average of 6.5 months. According to the Chinese medical association upper part of replantation function evaluation standard to assess efficacy trial, 52 cases were excellent, 3 cases were good, 3 cases were good, the excellent and good rate was 94.8%. CONCLUSIONS: The appearance and function is good after block from the broken replantation finger lateral organizations survive, as long as the patient general condition allows, away from the broken body is complete, there are available for blood vessels and nerves anastomosis, it should strive to reattach it.