Experimental investigation on pool boiling for downward facing heating with different concentrations of Al2O3 nanofluids

An experimental study has been conducted to examine the effect of different concentrations of α-Al2O3 nanofluids on boiling heat transfer for downward facing heating. The experimental results indicated that the surface heat transfer was enhanced with the rise of the nanofluids concentration, due to the bubble generation rate and disturbance increased. For downward facing heating, bubbles were not able to escape since the bouncy force influenced, and the vapor film appeared earlier as the increase of bubble generation rate. However, the heat transfer coefficient remains at a relatively high value in the early stage of film boiling, which suppresses the deterioration of heat transfer, due to the influences of nanofluids. As the various concentrations of nanofluids increased from 0 g/L to 0.012 g/L, it was found that the enhancement of the CHF (critical heat flux) up to 20.5%. After the nanofluids boiling, the surface roughness decreased and the wettability became worse. From the experimental phenomena, under the influence of these two factors, the bubble activity was enhanced.

A ketogenic diet impacts markers of mitochondrial mass in a tissue specific manner in aged mice

Declines in mitochondrial mass are thought to be a hallmark of mammalian aging, and a ketogenic diet (KD) may prevent the age-related decreases in mitochondrial content. The objective of this study was to investigate the impact of a KD on markers of mitochondrial mass. Mice were fed an isocaloric control diet (CD) or KD from 12 months of age. Tissues were collected after 1 month and 14 months of intervention, and a panel of commonly used markers of mitochondrial mass (mitochondrial enzyme activities and levels, mitochondrial to nuclear DNA ratio, and cardiolipin content) were measured. Our results showed that a KD stimulated activities of marker mitochondrial enzymes including citrate synthase, Complex I, and Complex IV in hindlimb muscle in aged mice. KD also increased the activity of citrate synthase and prevented an age-related decrease in Complex IV activity in aged brain. No other markers were increased in these tissues. Furthermore, the impacts of a KD on liver and kidney were mixed with no pattern indicative of a change in mitochondrial mass. In conclusion, results of the present study suggest that a KD induces tissue-specific changes in mitochondrial enzyme activities, or structure, rather than global changes in mitochondrial mass across tissues.

Effects of temperature frequency trends on projected japonica rice (Oryza sativa L.) yield and dry matter distribution with elevated carbon dioxide

In this study, we investigated the effects of temperature frequency trends on the projected yield and dry matter distribution of japonica rice (Oryza sativa L.) with elevated carbon dioxide (CO2) under future climate change scenarios in northwestern China. The Crop Environment Resource Synthesis (CERES)-Rice model was forced with the outputs from three general circulation models (GCMs) to project the rice growth and yield. Future temperature trends had the most significant impact on rice growth, and the frequency of higher than optimal temperatures (∼24-28 oC) for rice growth showed a marked increase in the future, which greatly restricted photosynthesis. The frequency of extreme temperatures (>35 oC) also increased, exerting a strong impact on rice fertilization and producing a significantly reduced yield. Although the increased temperature suppressed photosynthetic production, the elevated CO2 stimulated this production; therefore, the net result was determined by the dominant process. The aboveground biomass at harvest trended downward when temperature became the major factor in photosynthetic production and trended upward when CO2-fertilization dominated the process. The trends for the leaf and stem dry matter at harvest were affected not only by changes in photosynthesis but also by the dry matter distribution to the panicles. The trends for the rice panicle dry matter at harvest were closely related to the effects of temperature and CO2 on photosynthetic production, and extreme temperatures also remarkably affected these trends by reducing the number of fertilized spikelets. The trends of rice yield were very similar to those of panicle dry matter because the panicle dry matter is mostly composed of grain weight (yield). This study provides a better understanding of the japonica rice processes, particularly under extreme climate scenarios, which will likely become more frequent in the future.

Peri-prostatic adipose tissue measurements using MRI predict prostate cancer aggressiveness in men undergoing radical prostatectomy

OBJECTIVES

To evaluate the effect of peri-prostatic adipose tissue (PPAT) measurements using preoperative MRI on the prediction of prostate cancer (PCa) aggressiveness in men undergoing radical prostatectomy (RP).

METHODS

We performed a retrospective study on 179 consecutive patients receiving RP from June 2016 to October 2018. Clinical characteristics were collected. PPAT measurements including peri-prostatic fat area (PPFA) and peri-prostatic fat area to prostate area (PA) ratio (PPFA/PA) were calculated by MRI. Multivariable logistic regression analysis was performed to identify independent predictors of PCa lymph node metastasis (LNM). The predictive performance was estimated through ROC curves. Nomograms were created based on the predictors.

RESULTS

Pathologic Gleason score positively correlated with digital rectal examination (DRE), PSA, PPFA/PA, P504S, and Ki-67 (all P < 0.05). ROC curves revealed that high PPFA and high PPFA/PA were associated with LNM (both P < 0.05). Multivariate analysis revealed that high PPFA/PA, pathologic Gleason score, pT stage, and Ki-67 were independently predictive of LNM. The nomograms were created and the C-index was 0.945.

CONCLUSIONS

PPFA/PA is an independent predictor for LNM along with Gleason score, pT stage, and Ki-67. PPFA/PA may help predict LNM in men undergoing RP, thus providing adjunctive information for therapeutic strategy and prognosis.

[C-reactive protein and direct bilirubin as the early diagnostic indicators of primary hepatocellular carcinoma combined with macrovascular invasion]

Objective: To explore the early clinical diagnostic indicators in patients with primary hepatocellular carcinoma (HCC) combined with macrovascular invasion. Methods: The clinical data of 180 cases of HCC diagnosed by histopathology examination in the Second Affiliated Hospital of Chongqing Medical University from 2012 to 2019 were retrospectively analyzed. The factors influencing the development of macrovascular invasion in HCC patients were analyzed. The receiver operating characteristic curve (ROC curve) was used to evaluate the sensitivity and specificity. Results: Serum C-reactive protein (CRP) level was significantly correlated with various clinical characteristics of HCC patients, including the maximum tumor diameter, tumor number, and macrovascular invasion. Further analysis of the risk factors showed that serum direct bilirubin and CRP were independent risk factors for macrovascular invasion in HCC patients, with odds ratios of 1.747 (95% CI 1.119-2.728, P = 0.014) and 2.376 (95% CI 1.495-3.775, P < 0.001). ROC curve analysis showed that serum CRP, direct bilirubin, and the combination of the both had certain diagnostic value for hepatocellular carcinoma combined with macrovascular invasion. The area under the curve, sensitivity and specificity was 0.724, 0.668, 0.743, 79.1%, 70.1%, 79.1%, and 61.9%, 62.8%, 67.3%, respectively. Conclusion: The combination of CRP with direct bilirubin can be used as an important clinical diagnostic indicator for early diagnosis and prevention of hepatocellular carcinoma combined with macrovascular invasion.

Burden of respiratory infections and otitis media in the Inuit population of Nunavik, Quebec, Canada

BACKGROUND

Respiratory infections are a major health problem in the Inuit population of Nunavik, province of Quebec, Canada.

OBJECTIVES

A study was undertaken to assess the burden of lower (LRTI) and upper respiratory tract infections (URTI) and otitis media (OM) and to explore some of their determinants including the pneumococcal conjugate vaccine (PCV) status.

METHODS

The reference population includes children less than 5 years of age born in 1994-2010 and a sample of 825 children was selected for this study. Outpatient medical records were reviewed. Visits with a diagnosis of LRTI, URTI and OM were extracted. Univariate and multivariate statistical analyses were performed to identify predictors of disease risk.

RESULTS

The average number of LRTI, URTI and OM episodes were, respectively, 2.6, 6.2 and 5.9 from birth up to the 5th birthday. Seasonal patterns were similar for URTI and OM, but was different for LRTI. Children who received the recommended 4 PCV doses had a lower LRTI and OM risk than unvaccinated children. There was a trend towards a lower OM risk associated with a mixed PCV10+ PCV13 schedule compared with PCV7.

CONCLUSION

Results suggest a lower LRTI and OM risk associated with PCV use in this high-risk population but respiratory disease risk remains high compared with the general population in Quebec.

[Application of two-stage crestal approach sinus elevation in severe atrophic posterior maxilla]

Objective: To investigate the feasibility of two-stage crestal approach sinus elevation in severe atrophic maxilla. Methods: A total of 25 patients (male: 13 cases,female: 12 cases) who attended Department of Implant Center, Stomatological Hospital, Southern Medical University from May 2016 to May 2018 were included in this study. The age of the patients was 32-49 years old. The inclusion criteria were: single or multiple tooth loss in posterior maxilla with residual bone height ranged from 1.5 to 3.0 mm and vertical bone width≥6 mm, no pathological changes or septum were detected in the sinus. The elevated sides were divided into three groups according to different buccal-palatal sinus width (SW): wide (16 case, SW＞15 mm), normal (12 case, 12 mm≤SW≤15 mm), narrow (5 case, SW<12 mm). Finally, 23 patients with 33 implants were placed by the two-stage crestal approach for sinus elevation. Six months after implant placement, final restorations were delivered. Implant survival rate, implant stability quotient (ISQ), immediate vertical bone height (VBH) after surgeries, changes of sinus elevation height (cSEH), marginal bone loss (MBL) at 1 year follow-up were examined. Results: Twenty-three patients were finally included in the study, including 12 males and 11 females, aged (41.2±7.6) years old. All implants healed uneventfully. ISQ (wide: 50.81±2.69; normal: 60.58±2.54; narrow: 63.12±3.58), immediate VBH after 1st surgery [wide: (7.99±1.13) mm; normal: (8.95±0.81) mm; narrow: (9.18±0.90) mm] and 2nd surgery [wide: (11.46±0.88) mm; normal: (12.77±0.49) mm; narrow: (12.57±0.55) mm], cSEH six months after 1st [wide: (3.87±0.43) mm; normal: (2.01±0.65) mm; narrow: (1.49±0.33) mm] and 2nd [wide: (1.16±0.29) mm; normal: (1.04±0.33) mm ; narrow: (0.97±0.41) mm] surgery, MBL [wide: (0.91±0.05) mm; normal: (0.79±0.10) mm; narrow: (0.74±0.07) mm] were significantly different among three groups (P<0.05). In all the three groups, cSEH was barely detected at 1-year follow-up (P>0.05). Conclusions: Two-stage crestal approach for sinus elevation might be an alternative protocol in severe atrophic posterior maxilla, especially in cases with narrow and normal buccal-palatal width. There is an urgent need for long time follow-up and more clinical cases.

[Progress in research of association of adverse childhood experiences with prevalence of common chronic diseases in adulthood]

The effects of adverse childhood experiences on adult health has aroused increasing concern in the world in recent years, but limited studies have been conducted in China. This study synthesized the measurement of adverse childhood experiences, the association between adverse childhood experiences and the prevalence common chronic diseases in adulthood and possible mechanisms. It was found that though measurement range of adverse childhood experiences might be different among studies, current used measurement scales basically met the requirement of disease prevention. Most categories of adverse childhood experiences were positively related to risk of common chronic diseases, and the relationship was influenced by social economic status, sex and age. However, people with exposure to famine in childhood had lower prevalence of hypertension compared with those without the exposure. The possible mechanisms might be that the occurrence of adverse childhood experiences might damage physiological functions or increase the adoption of poor healthy behaviors and lifestyles, and finally increased the risk of chronic diseases directly or indirectly. While premature death due to adverse childhood experiences might reverse the association because of nonrandom selection. It is necessary for us to select appropriate indexes of adverse childhood experiences and conduct more studies to prove the association between adverse childhood experiences and prevalence of common chronic diseases in adulthood and explore the related mechanism for the better prevention of chronic diseases in China.