N-Indole-Substituted Imidazolylidene Pd-PEPPSI Precatalysts: Enhanced Performance with a 3,5-Diisopropyl-4-indolyl Moiety.

Pd-PEPPSI complexes of N-(4-indolyl)-N'-phenylimidazol-2-ylidene (IIn) ligands with a 5-isopropyl-4-indolyl moiety are synthesized and evaluated in heteroarene C-H arylation, Suzuki-Miyaura cross-coupling, and Buchwald-Hartwig amination reactions. The IIn-Pd complex bearing a 3,5-diisopropyl-4-indolyl substituent (C5) exhibits the best catalytic activity in this series and substantially outperforms commercial precatalyst PEPPSI-Pd-IPr. The results also suggest that the alkyl group at position 3 of the 4-indolyl moiety shows stronger impacts than that at position 5.

Biochar-manure compost in conjunction with pyroligneous solution alleviated salt stress and improved leaf bioactivity of maize in a saline soil from central China: a 2-year field experiment.

BACKGROUND: Salinity is a major stress threatening crop production in dry lands. A 2-year field experiment was conducted to assess the potential of a biochar product to alleviate salt-stress to a maize crop in a saline soil. The soil was amended with a compost at 12 t ha(-1) of wheat straw biochar and poultry manure compost (BPC), and a diluted pyroligneous solution (PS) at 0.15 t ha(-1) (BPC-PS). Changes in soil salinity and plant performance, leaf bioactivity were examined in the first (BPC-PS1) and second (BPC-PS2) year following a single amendment. RESULTS: While soil salinity significantly decreased, there were large increases in leaf area index, plant performance, and maize grain yield, with a considerable decrease in leaf electrolyte leakage when grown in amendments. Maize leaf sap nitrogen, phosphorus and potassium increased while sodium and chloride decreased, leaf bioactivity related to osmotic stress was significantly improved following the treatments. These effects were generally greater in the second than in the first year. CONCLUSION: A combined amendment of crop straw biochar with manure compost plus pyroligneous solution could help combat salinity stress to maize and improve productivity in saline croplands in arid/semi-arid regions threatened increasingly by global climate change.

Pathogenic factors of maxillary sinus mucosal thickening observed by cone-beam computed tomography (CBCT).

OBJECTIVE: To explore the pathogenic factors associated with maxillary sinus mucosal thickening with Cone-beam computed Tomography (CBCT). METHODS: From 2016 through 2020, 93 patients with periapical periodontitis or periodontitis in the maxillary posterior dental region were selected. RESULTS: The preoperative thickness of the periodontitis group was significantly higher than that of the periapical periodontitis group (P < 0.05). The difference achieves statistical significance for the comparison of the thickness change with various severity of inflammation (F = 54.824, P = 0.000), the change with time (F = 312.741, P = 0.000). and the change with the interaction severity of inflammation and time（F = 86.132, P = 0.000). CONCLUSIONS: Patients with maxillary sinus mucosa thickening caused by periodontitis and periapical periodontitis should be extracted their infectious teeth and get thoroughly debridement. Maxillary sinus augmentation can perform favorable efforts 3-6 months after extracting teeth.

Are automated accounts driving scholarly communication on Twitter? a case study of dissemination of COVID-19 publications.

From a network perspective, this study analyzes 659 users mentioning sampled COVID-19 articles 10 or more times on Twitter with a focus on their roles in facilitating the process of scholarly communication. Different from existing studies, we consider both the user types and the automation of accounts to profile influential users in the network of research dissemination. Our study found that similar to academic users, non-academic users can also be active players in communicating scientific publications. The results highlight the intensive interactions between human users and automated accounts, including bots and cyborgs, which accounted for 45% of connections among the top users. This study also demonstrates the important role of automated accounts in initiating and facilitating research dissemination. Specifically, (1) bot-assisted academic publishers showed the highest amplifier scores, which measures a user's tendency of being the first to share information and reach out to others within their trusted networks, (2) 5.28% of the selected articles was first tweeted by automated research feeds, ranking the fourth among the 22 classified user groups, and (3) bot-assisted publishers and automated feeds of generic topics and news alerts were highly ranked in authority, a network measure to quantify the degree to which a user consumes important resources of relevant topics. In the conclusion section, we discuss future directions to improve the validity of Twitter metrics in assessing research impacts.

Evaluation of volume changes following lateral window maxillary sinus floor elevation using Minics software.

Background: Significant volume changes at the site of lateral window maxillary sinus floor elevation have been reported 6 months postoperatively, with stabilization thereafter. However, at present, there is no consensus regarding the gold standard to assess the shape and volume of the bone graft site after implantation. This study aimed to analyze volume changes in the lateral window maxillary sinus floor elevation region using Minics software. Methods: We analyzed 40 patients who underwent lateral window maxillary sinus floor elevation surgery at the Stomatology Department of Binhaiwan Central Hospital, Dongguan, China between 2017 and 2020. Twenty patients underwent lateral window maxillary sinus floor elevation with simultaneous implantation, while 20 patients underwent lateral window maxillary sinus floor elevation with delayed implantation 6 months later. Minics software was used for three-dimensional analysis of the elevation site on the day after surgery (T1) and 6 months after surgery (T2) in both groups. Results: The elevation site volume was reduced 6 months after lateral window maxillary sinus floor elevation. The differences in the length, width, height from the tip, and volume of the implant between T1 and T2 were statistically significant. Conclusions: The length, width, height, and volume of the lateral window maxillary sinus floor elevation region were reduced using Minics software, suggesting that the volume of the elevation site should be enlarged as much as possible during the operation to prevent volume shrinkage.

Impact of High-Altitude Hypoxia on Early Osseointegration With Bioactive Titanium.

Nowadays, the bone osseointegration in different environments is comparable, but the mechanism is unclear. This study aimed to investigate the osseointegration of different bioactive titanium surfaces under normoxic or high-altitude hypoxic environments. Titanium implants were subjected to one of two surface treatments: (1) sanding, blasting, and acid etching to obtain a rough surface, or (2) extensive polishing to obtain a smooth surface. Changes in the morphology, proliferation, and protein expression of osteoblasts on the rough and smooth surfaces were examined, and bone formation was studied through western blotting and animal-based experiments. Our findings found that a hypoxic environment and rough titanium implant surface promoted the osteogenic differentiation of osteoblasts and activated the JAK1/STAT1/HIF-1α pathway in vitro. The animal study revealed that following implant insertion in tibia of rabbit, bone repair at high altitudes was slower than that at low altitudes (i.e., in plains) after 2weeks; however, bone formation did not differ significantly after 4weeks. The results of our study showed that: (1) The altitude hypoxia environment would affect the early osseointegration of titanium implants while titanium implants with rough surfaces can mitigate the effects of this hypoxic environment on osseointegration, (2) the mechanism may be related to the activation of JAK1/STAT1/HIF-1α pathway, and (3) our results suggest the osteogenesis of titanium implants, such as oral implants, is closely related to the oxygen environment. Clinical doctors, especially dentists, should pay attention to the influence of hypoxia on early osseointegration in patients with high altitude. For example, it is better to choose an implant system with rough implant surface in the oral cavity of patients with tooth loss at high altitude.

[Surveying on menstruation status of reproductive age women of Han nationality in Liaoning province in 2008].

OBJECTIVE: To investigate the menstruation status of reproductive age women of Han Nationality in Liaoning province. METHODS: From Apr. 2008 to Dec. 2008, 1611 women at age of 19-45 years from Shenyang, Yingkou, Benxi, Zhangwu were enrolled in this study according to epidemiologic cluster sampling method. The study was performed by questionnaire consisting of age of menarche, regularity of menstruation, menstrual cycle and dysmenorrhea, et al. RESULTS: In the survey of 1611 women, the average menarche age is 14.4 years old, there were significant difference on menarche between (14.2 +/- 1.5) years in women from city and (14.6 +/- 1.5) years in women from country (t = 6.58, P < 0.01). The linear regression statistic method was used to analyze the relationship between age and menarche age, the linear regression equation was gotten as Y = 0.074X + 11.855, which means 1 year increase was associated with decrease by 0.074 years in menarche age approximately. About 86.34% (1391/1611) of women have normal and regular menstrual cycle at range of 21 to 35 days, while 11.05% (178/1611) of women have longer menstrual cycle (> 35 days) and 2.61% (42/1611) of women have shorter menstrual cycle (< 21 days). Of which 65.67% (1058/1611) women have regular menstrual cycle just after menarche, 94.97% (1530/1611) of women would have regular menstruation in 2 years after menarche. The rate of dysmenorrhea was 42.09% (678/1611), of which 13.6% (92/678) women have high severe pelvic pain. CONCLUSION: Our results suggested that the trend went toward younger ages of menarche, which was younger menarche age in women from city than country. About 95% women would have regular menstrual cycle within 2 years after menarche.

Hydrogen-rich saline ameliorates hippocampal neuron apoptosis through up-regulating the expression of cystathionine ß-synthase (CBS) after cerebral ischemia- reperfusion in rats.

OBJECTIVES: This study aimed to evaluate the potential role of hydrogen in rats after cerebral ischemic/reperfusion (I/R) injury. MATERIALS AND METHODS: The experimental samples were composed of sham group, model group of rats that received middle cerebral artery occlusion (MCAO) for 2 hr followed by reperfusion for 24 hr, and the hydrogen saline group treated by hydro¬gen-rich saline (1 ml/kg) after MCAO. Hydrogen sulfide (H2S), S100-ßprotein (S100-ß), and neuron-specific enolase (NSE) levels were measured; the levels of malondialdehyde (MDA), reactive oxygen species (ROS), and superoxide dismutase (SOD) were detected; the histologic structure and apoptotic cells of hippocampus were observed; the expressions of cystathionine ß-synthase (CBS), nuclear factor erythroid 2-related factor 2 (Nrf2), and hemeoxygenase-1 (HO-1) were measured. Statistical analyses were performed using one-way analysis of variance (ANOVA) followed by Fisher's least significant difference (LSD) test. RESULTS: Our results showed that hydrogen up-regulated H2S levels via promoting the expression of CBS in the hippocampus, and its treatment alleviated oxidative stress via activating the expression of Nrf2 and HO-1, and then cell apoptosis reduced, furthermore, brain function improved by down-regulating the levels of S100-ßand NSE. CONCLUSION: This study showed that hydrogen-rich saline ameliorates cell injury through up-regulating the expression of CBS in the hippocampus after cerebral ischemia reperfusion (I/R) in rats, this provides new experimental evidence for the treatment of stroke with hydrogen saline.