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Soil organic matter (SOM) is a key index of soil fertility. Calculating spectral index and screening characteristic band reduce redundancy information of hyperspectral data, and improve the accuracy of SOM prediction. This study aimed to compare the improvement of model accuracy by spectral index and characteristic band. This study collected 178 samples of topsoil (0–20 cm) in the central plain of Jiangsu, East China. Firstly, visible and near-infrared (VNIR, 350–2500 nm) reflectance spectra were measured using ASD FieldSpec 4 Std-Res spectral radiometer in the laboratory, and inverse-log reflectance (LR), continuum removal (CR), first-order derivative reflectance (FDR) were applied to transform the original reflectance (R). Secondly, optimal spectral indexes (including deviation of arch, difference index, ratio index, and normalized difference index) were calculated from each type of VNIR spectra. Characteristic bands were selected from each type of spectra by the competitive adaptive reweighted sampling (CARS) algorithm, respectively. Thirdly, SOM prediction models were established based on random forest (RF), support vector regression (SVR), deep neural networks (DNN) and partial least squares regression (PLSR) methods using optimal spectral indexes, denoted here as SI-based models. Meanwhile, SOM prediction models were established using characteristic wavelengths, denoted here as CARS-based models. Finally, this research compared and assessed accuracy of SI-based models and CARS-based models, and selected optimal model. Results showed: (1) The correlation between optimal spectral indexes and SOM was enhanced, with absolute value of correlation coefficient between 0.66 and 0.83. The SI-based models predicted SOM content accurately, with the coefficient of determination (R2) and root mean square error (RMSE) values ranging from 0.80 to 0.87, 2.40 g/kg to 2.88 g/kg in validation sets, and relative percent deviation (RPD) value between 2.14 and 2.52. (2) The accuracy of CARS-based models differed with models and spectral transformations. For all spectral transformations, PLSR and SVR combined with CARS displayed the best prediction (R2 and RMSE values ranged from 0.87 to 0.92, 1.91 g/kg to 2.56 g/kg in validation sets, and RPD value ranged from 2.41 to 3.23). For FDR and CR spectra, DNN and RF models achieved more accuracy (R2 and RMSE values ranged from 0.69 to 0.91, 1.90 g/kg to 3.57 g/kg in validation sets, and RPD value ranged from 1.73 to 3.25) than LR and R spectra (R2 and RMSE values from 0.20 to 0.35, 5.08 g/kg to 6.44 g/kg in validation sets, and RPD value ranged from 0.96 to 1.21). (3) Overall, the accuracy of SI-based models was slightly lower than that of CARS-based models. But spectral index had a good adaptability to the models, and each SI-based model displayed the similar accuracy. For different spectra, the accuracy of CARS-based model differed from modeling methods. (4) The optimal CARS-based model was model CARS-CR-SVR (R2 and RMSE: 0.92 and 1.91 g/kg in validation set, RPD: 3.23). The optimal SI-based model was model SI3-SVR (R2 and RMSE: 0.87 and 2.40 g/kg in validation set, RPD: 2.57) and model SI-SVR (R2 and RMSE: 0.84 and 2.63 g/kg in validation set, RPD: 2.35). [ABSTRACT FROM AUTHOR]

The mandatory implementation of the standards laid out in the Energy Efficiency Existing Ship Index (EEXI) and the Carbon Intensity Indicator (CII) requires ships to improve their efficiency and thereby reduce their carbon emissions. To date, the steam Rankine cycle (RC) has been widely used to recover wasted heat from marine main engines to improve the energy-conversion efficiency of ships. However, current marine low-speed diesel engines are usually highly efficient, leading to the low exhaust gas temperature. Additionally, the temperature of waste heat from exhaust gas is too low to be recovered economically by RC. Consequently, a solution has been proposed to improve the overall efficiency by means of waste heat recovery. The exhaust gas is bypassed before the turbocharger, which can decrease the air excess ratio of main engine to increase the exhaust gas temperature, and to achieve high overall efficiency of combined cycle. For quantitative assessments, a semi-empirical formula related to the bypass ratio, the excess air ratio, and the turbocharging efficiency was developed. Furthermore, the semi-empirical formula was verified by testing and engine model. The results showed that the semi-empirical formula accurately represented the relationships of these parameters. Assessment results showed that at the turbocharging efficiency of 68.8%, the exhaust temperature could increase by at least 75 °C, with a bypass ratio of 15%. Moreover, at the optimal bypass ratio of 11.1%, the maximum overall efficiency rose to 54.84% from 50.34%. Finally, EEXI (CII) decreased from 6.1 (4.56) to 5.64 (4.12), with the NOx emissions up to Tier II standard. [ABSTRACT FROM AUTHOR]

Pulmonary alveolar proteinosis (PAP) is a rare diffuse lung disease characterized by the accumulation of intra-alveolar lipoprotein-like surfactants. Lung core biopsy and bronchoalveolar lavage (BAL) fluid are currently the two major sources of sampling for diagnosis. In the present study, we assessed the value of induced sputum in diagnosing PAP by transmission electron microscopy and examined the PAP 2-year death rate in Asians. Transmission electron microscopy was performed on the samples from 17 patients with PAP, 13 patients with inflammatory lung diseases, and 13 healthy adults. The PAP patients were followed up for 3–156 months, and inflammatory lung diseases patients or healthy adults for 12–36 months. The ultrastructural features including diagnostic lamellar bodies of induced sputum deposition (ISD) samples were similar to that of the BAL fluid sediment. However, the rates of lamellar bodies were 73.7% in the ISD group, significantly higher than the spontaneous sputum deposition (SSD) group (42.1%, P <.0487) and similar to the BAL sediment (76.2%) and the lung biopsy (54.5%) groups. The overall 2-year death rate of our PAP patients was 17.6% (3/17), not statistically different from the healthy adults and patients with inflammatory diseases (0/13, P =.237 for both). ISD may be the preferred non-invasive sampling method for diagnosing PAP by electronic microscopy because of the higher diagnostic yield than SSD. The diagnostic yields of this noninvasive method were similar to that of lung core biopsy and BAL. [ABSTRACT FROM AUTHOR]

Sessile serrated adenomas (SSA) and traditional serrated adenomas (TSA) are considered as precursors of colorectal cancer, and are often diagnostic challenges. Their true prevalence is masked by significant inter-observer variations. To investigate the true prevalence and synchronous colorectal carcinoma (sCRC) of colorectal serrated polyps (CSP) and their associated factors, we first retrospectively identified all colorectal polyps collected at our institution between June 1995 and May 2013. After centrally reclassifying all CSP to reduce inter-observer variations, Chi-square tests and logistic regression analyses were used to analyze the potential factors. Among the included 5501 colorectal polyps, 499 CSP of 428 patients were identified and studied, including 353 hyperplastic polyps (HP, 70.7%), 80 SSA (16.0%), 61 TSA (12.2%) and 5 mixed polyp (1.0%). Diagnostic disagreements were found in 68 CSP (13.63% of CSP). SSA and TSA were more often larger than 5 mm and in proximal colon than HP. SSA were also more likely associated with older age (p=0.005), size ≥5 mm (p<0.001) and ≥3 polyps (p=0.004) than HP in distal colon, but only more likely associated with older age (p=0.006) in proximal colon. Multivariate regression analysis demonstrated that CSP with sCRC, compared with CSP without sCRC, were linked to CSP size ≥1 cm (vs <1 cm, odds ratio [OR] 4.412, 95% confidence interval [CI] 1.684-11.556, P=0.003) and a diagnosis of SSA or TSA (vs HP, OR 6.194, 95% CI 1.870-20.513, P=0.003 and OR 6.754, 95% CI 1.981-23.028, P=0.002, respectively), but not age, gender, polyp number and polyp shape. SSA and TSA are similarly often associated with sCRC (P=0.460). In conclusion, histology subtypes and polyp size may serve as markers for sCRC of CSP. SSA and TSA may warrant careful endoscopic examinations and similar follow-up intervals.

Objective: To investigate clinicopathological characteristics of colorectal sessile serrated adenoma/polyp (SSA/P) and its differential diagnosis from other serrated lesions., Methods: Clinicopathological features of all cases of colorectal serrated lesions from 5 209 colorectal biopsy samples at Shanghai Tongji Hospital from 2008 to 2013 were reviewed. Three hundred and fifty-three cases of serrated lesions were erolled in the study. Morphological features of SSA/P were investigated with an emphasis on histologic criteria for diagnosis and a literature review was performed., Results: Three hundred and fifty-three cases of serrated lesions were identified, including 25 SSA/P (7.1%), 278 hyperplastic polyp (HP, 78.8%), and 44 traditional serrated adenoma (TSA, 12.5%). Twenty-five patients with SSA/P consisted of 16 males and 9 females with a mean age of 62.2 years (aged 34-84 years) and the lesions involved sigmoid colon (14 cases), ascending colon (9 cases), rectum (1 case) and transverse colon (1 case). Grossly, the majority of SSA/P was sessile with an averaged size of 0.73 cm. Histologically, typical SSA/P had elongated crypts with prominent serration and distorted crypts architecture. The detection rates of crypts dilatation and branching in SSA/P and HP were 100% (25/25) and 24% (12/50, P < 0.01), 72% (18/25) and 4% (2/50, P < 0.01), respectively. Morphological features observed only in SSA/P included L-shaped crypts (48%, 12/25), pseudo infiltration of mucosa muscle (16%, 4/25), atypical nuclei (32%, 8/25), and increased mucus secretion (24%, 6/25)., Conclusions: SSA/P microscopically shows prominent serration and abnormal architectures of crypts. Complete tissue sectioning and correct embedding are helpful for the diagnosis. SSA/P without cytological dysplasia should be distinguished from HP, especially those with only a few distorted crypts.

An immunocompetent 50-year-old male presented with slight cough and occasional lung congestion. The radiologic findings included diffuse, bilateral reticular and one nodular opacity at the upper lobe of right lung without clear margin. A wedge resection of the lesion showed disordered distribution of the medium-sized vessels and arterioles, several arterioles densely gathered including a few occlusive arterioles, or medium veins dilated with irregular and elongated cavity, indicating the existence of vascular malformation. Interestingly, near to the malformed vessels, a large area of necrosis with granulomatous inflammation was found. Of note, numerous intracytoplasmic organisms with a nucleus, a wall and a thick capsule, were free in the alveoli or located within the macrophages and polykaryocytes, suggesting cryptococci infection. This is to our best knowledge the first case showing concurrent vascular malformation and local pulmonary cryptococcosis, and vascular malformation was likely an important pathological predisposing factor for local pulmonary cryptococcosis infection.