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We report on 2D simulations of dark current for InP/In0.53Ga0.47aAs/InP p-i-n photodiode. Our simulation result is in good agreement with experiment confirming that generation-recombination effect is the dominant source of the dark current at low bias. Effects of the thickness and doping concentration of the absorption layer on the dark current are discussed in detail. [ABSTRACT FROM AUTHOR]

Passivation of the electronic defect states at a SiNx/InGaAs interface has been achieved using (NH4)2Sx treatments of the InGaAs surface. The X-ray photoelectron spectroscopy technique was used to investigate the mechanism of sulfur passivation. The results indicate that sulfur treatment can effectively erase the native oxides, and S-In, S-Ga and S-As bondings are formed after sulfidation. The fabrication of Au/SiNx/InGaAs metal–insulator–semiconductor diodes has been achieved by depositing a layer of SiNx on (NH4)2Sx-treated n-InGaAs using the plasma enhanced chemical vapor deposition technique. The effect of passivation on the InGaAs surface before and after annealing was evaluated by current–voltage and capacitance–voltage measurements. The results indicate that the SiNx passivation layer exhibits good insulative properties. The annealing contributes to the decrease of the fixed charge density and the minimum surface state density, which are 4.5×1011 cm-2 and 3.92×1011 cm-2 eV-1, respectively. A 256×1 InP/InGaAs/InP heterojunction short-wavelength infrared detector, fabricated with the sulfidation plus a SiNx passivation layer, has shown a good response uniformity of 4.81%. [ABSTRACT FROM AUTHOR]

The influence of defects on the responsivity of GaN Schottky barrier ultraviolet photodetectors with n--GaN/n+-GaN layer structures is investigated. It is found that employing undoped GaN instead of Si-doped GaN as the n--GaN layer brings about a higher responsivity due to a lower Ga vacancy concentration. On the other hand, the dislocations may increase the recombination of electron-hole pairs and enhance the surface recombination in the photodetectors. Employing undoped GaN and reducing the dislocation density in the n--GaN layer are necessary to improve the responsivity of Schottky barrier photodetectors. [ABSTRACT FROM AUTHOR]

Passivation of the electronic defect states at a SiNx/InGaAs interface has been achieved using (NH4)2Sx treatments of the InGaAs surface. The X-ray photoelectron spectroscopy technique was used to investigate the mechanism of sulfur passivation. The results indicate that sulfur treatment can effectively erase the native oxides, and S-In, S-Ga and S-As bondings are formed after sulfidation. The fabrication of Au/SiNx/InGaAs metal–insulator–semiconductor diodes has been achieved by depositing a layer of SiNx on (NH4)2Sx-treated n-InGaAs using the plasma enhanced chemical vapor deposition technique. The effect of passivation on the InGaAs surface before and after annealing was evaluated by current–voltage and capacitance–voltage measurements. The results indicate that the SiNx passivation layer exhibits good insulative properties. The annealing contributes to the decrease of the fixed charge density and the minimum surface state density, which are 4.5×1011 cm-2 and 3.92×1011 cm-2 eV-1, respectively. A 256×1 InP/InGaAs/InP heterojunction short-wavelength infrared detector, fabricated with the sulfidation plus a SiNx passivation layer, has shown a good response uniformity of 4.81%. [ABSTRACT FROM AUTHOR]

Objective: To explore the effects of early debridement and conservative eschar removal followed by wound coverage with acellular dermal matrix (ADM), i.e., early surgery, in the treatment of children with deep burns. Methods: This study was a retrospective cohort study. From January 2017 to December 2022, 278 deep burned hospitalized children aged 1-7 years who met the inclusion criteria were admitted to Central Hospital Affiliated to Shandong First Medical University. According to the differences in treatment processes, 134 children who underwent early surgery+routine dressing change were enrolled in eschar removal+dressing change group (77 males and 57 females, aged 1 (1, 2) years), and 144 children who underwent only routine dressing change were enrolled in dressing change alone group (90 males and 54 females, aged 1 (1, 2) years). Fifty-one children without full-thickness burns in eschar removal+dressing change group were enrolled in eschar removal+dressing change group 1 (26 males and 25 females, aged 1 (1, 2) years), and 57 cases of the 83 children with full-thickness burns who did not undergo autologous skin grafting at the same time of early surgery (namely early skin grafting) in eschar removal+dressing change group were included in eschar removal+dressing change group 2 (37 males and 20 females, aged 1 (1, 2) years). Seventy-six children without full-thickness burns in dressing change alone group were included in dressing change alone group 1 (51 males and 25 females, aged 1 (1, 3) years), and 68 children with full-thickness burns in dressing change alone group were included in dressing change alone group 2 (39 males and 29 females, aged 1 (1, 2) years). For deep partial-thickness burn wounds and small full-thickness burn wounds in eschar removal+dressing change group, the eschar removal was performed on the basis of retaining a thin layer of denatured dermis so as to preserve the healthy tissue of the wound base, and ADM was applied to all wounds externally after eschar removal. For larger full-thickness burn wounds in this group, especially those located in the functional part of joints, eschar removal to the plane layer of viable tissue and early autologous skin grafting was needed. When the superficial wounds of children healed or tended to heal, the residual wounds were evaluated, and elective autologous skin grafting was performed if it was difficult to heal within 14 days. The healing time, intervention healing time, times of operation/dressing change, and times of intervention operation/dressing change in children with deep partial-thickness burn wounds of children in eschar removal+dressing change group, dressing change alone group, eschar removal+dressing change group 1, and dressing change alone group 1 were recorded. At the last follow-up (follow-up period was set to 7-12 months), the modified Vancouver scar scale (mVSS) scores of the most severe area of scar hyperplasia of healed deep partial-thickness burn wounds of 54 children in eschar removal+dressing change group and 48 children in dressing change alone group were recorded. The healing time and times of operation/dressing change of all burn wounds of children in eschar removal+dressing change group and dressing change alone group, and the healing time and times of operation/dressing change of full-thickness burn wounds of children in eschar removal+dressing change group 2 and dressing change alone group 2 were recorded. The incidences of wound infection, sepsis, fever, and fever after 5 days of burns in children of eschar removal+dressing change group and dressing change alone group during wound healing. Results: Compared with those in dressing change alone group, the healing time and intervention healing time were significantly shortened, and the times of operation/dressing change and times of intervention operation/dressing change were significantly reduced in children with deep partial-thickness burn wounds in eschar removal+dressing change group (with Z values of -11.00, -11.33, -12.64, and -11.65, respectively, P <0.05). Compared with those in dressing change alone group 1, the healing time and intervention healing time were significantly shortened, and the times of operation/dressing change and times of intervention operation/dressing change were significantly reduced in children with deep partial-thickness burn wounds in eschar removal+dressing change group 1 (with Z values of 6.57, 6.46, 8.04, and 6.57, respectively, P <0.05). At the last follow-up, the mVSS score of the most severe scar hyperplasia area of healed deep partial-thickness burn wounds of 54 children in eschar removal+dressing change group was 4.00 (3.00,5.00), which was significantly lower than 6.50 (5.00,7.00) of 48 children in dressing change alone group ( Z =-4.67, P <0.05).Compared with those in dressing change alone group, the healing time was significantly shortened, and times of operation/dressing change was significantly reduced in all burn wounds in eschar removal+dressing change group (with Z values of -5.20 and -6.34, respectively, P <0.05). Compared with those in dressing change alone group 2, the healing time was significantly shortened, and times of operation/dressing change was significantly reduced in full-thickness burn wounds in eschar removal+dressing change group 2 (with Z values of -5.22 and -5.73, respectively, P <0.05). During wound healing, the probabilities of fever and fever after 5 days of burns in children of eschar removal+dressing change group were significantly lower than those in dressing change alone group (with χ 2 values of 4.13 and 3.91, respectively, P <0.05); only 1 child in dressing change alone group developed sepsis, and there was no statistically significant difference in the wound infection rate of children in the two groups ( P >0.05). Conclusions: For children with deep burns, early surgery, and early skin grafting or elective autologous skin grafting as needed, have better short-term and long-term effects than those without early surgery.

Objective: To observe the changes of the expression level of long non-coding RNA (lncRNA) KCNQ1OT1 and microRNA (miR)-146a-3p in placenta tissues of preeclampsia (PE) patients, as well as their effect and mechanism on the biological functions of trophoblast cells. Methods: A total of 45 cases of hospitalized PE patients in Hainan General Hospital from July 2017 to July 2018 were selected as the PE group, 55 normal pregnant women during the same period were chosed as the control group. The expression level of KCNQ1OT1 mRNA and miR-146a-3p in the placenta tissues between two groups were detected by using quantitative real time (qRT)-PCR. Pearson's test was furtherly analyzed the correlation between them. Human trophoblast cell line (HTR8/SVneo) were randomly divided into control and lipopolysaccharide (LPS) groups, and then LPS group were divide into four sub-groups,included LPS group, short hairpin RNA (sh)-KCNQ1OT1 (after silencing the expression of KCNQ1OT1), miR-146a-3p inhibitor and sh-KCNQ1OT1+miR-146a-3p inhibitor. The targeting relationship between KCNQ1OT1 and miR-146a-3p were predicted by bioinformatics software and confirmed by luciferase assay. The cell proliferation and invasion capacities were respectively detected by cell counting kit-8 (CCK-8) and transwell assay. The expression level of KCNQ1OT1 mRNA and miR-146a-3p were detected by qRT-PCR and the protein expression level of CXC chemokine ligand 12 （CXCL12） and CXC chemokine receptor type 4 (CXCR4) were tested by western blot. Results: (1) The mRNA expression level of KCNQ1OT1 in the placenta of PE group was lower than that of control group (0.23±0.03 vs 0.51±0.04, P <0.05), and the miR-146a-3p expression level was higher than that of the control group (0.49±0.03 vs 0.31±0.03, P <0.05), there were statistical significant differences between the two groups. (2) Luciferase assay showed that there was a targeting relationship between KCNQ1OT1 and mir-146a-3p. Compared with the control group, the mRNA expression level of KCNQ1OT1 in the LPS group were significantly decreased (0.91±0.03 vs 0.35±0.03, P <0.05), and the expression level of miR-146a-3p were significantly increased (0.22±0.03 vs 0.63±0.04, P <0.05). The cell proliferation, invasion and migration capacities and the protein expression of CXCL12 and CXCR4 significantly reduced in the LPS group compared with control group (all P <0.05). The mRNA expression level of KCNQ1OT1 (0.23±0.03) in the sh-KCNQ1OT1 group were further decreased, the expression of miR-146a-3p (0.85±0.03) were further increased, and the cell proliferation, invasion and migration capacities and the protein expression of CXCL12 and CXCR4 were all further reduced compared with control group，there were significant difference between two groups (all P <0.05). Comparing the miR-146a-3p inhibitor group, and sh-KCNQ1OT1+miR-146a-3p inhibitor group with the sh-KCNQ1OT1 group, respectively, the expression level of KCNQ1OT1 mRNA (0.78±0.04 vs 0.50±0.03) increased, and the expression level of miR-146a-3p (0.42±0.03 vs 0.46±0.03) decreased, the cell proliferation, invasion and migration capacities and the protein expression of CXCL12 and CXCR4 were all increased ,there were statistically significant differences (all P <0.05). Conclusion: KCNQ1OT1 could target the regulation of miR-146a-3p through CXCL12/CXCR4 pathway in the proliferation, invasion an migration of HTR8/SVneo cells, which may be involved in the pathogenesis of PE.

Objective: To investigate the preparation of bioactive denatured acellular dermal matrix (DADM) from burn mice riched in mice bone marrow mesenchymal stem cells. Methods: Twelve BALB/c mice were collected and 20% total body surface area scalds (hereinafter referred to as burns) with deep partial thickness were inflicted on the back skin of each mouse. After removing epidermis, the burned skin were collected and divided into Triton X-100 group and elhylene diamine tetraacetic acid (EDTA) group according to the random number table, with 15 samples in each group. Samples in Triton X-100 group and EDTA group were respectively placed in mixture of 2.5 g/L Triton X-100 and 2.5 g/L trypsin solution and mixture of 0.2 g/L EDTA and 2.5 g/L trypsin solution for sustained vibration and elution for 24 hours to make mice DADM. The general appearance of DADM was observed. The structure and arrangement of collagen fibers of DADM were observed by scanning electron microscope and tissue structure of DADM were observed by fluorescence microscope. Bone marrow mesenchymal stem cells (BMSCs) from mice were transplanted in mice DADM in the two groups with concentration of 2×105 cells per well to prepare bioactive mice DADM. After cultured for 3 days, tissue structure of bioactive mice DADM was observed by hematoxylin and eosin staining, distribution and number of BMSCs of bioactive mice DADM were observed by immunofluorescence staining. Proliferation of BMSCs of bioactive mice DADM after cultured for 2 h, 1 d, 3 d, and 5 d was detected by cell count kit-8. Data were processed with analysis of variance for repeated measurement and t test. Results: (1) Mice DADM in the two groups were white in appearance with certain tenacity and elasticity. Mice DADM in the two groups maintained good three-dimensional porous network structure. Collagen fibers of mice DADM in EDTA group were with good continuity, and collagen fibers of mice DADM in Triton X-100 group were fractured in varying degrees. Mice DADM in the two groups were decellularized completely, and the collagen fibers were loose and arranged disorderly. The continuity of tissue structure of mice DADM in EDTA group was better than that of mice DADM in Triton X-100 group. (2) After cultured for 3 days, the BMSCs in bioactive mice DADM in the two groups were evenly distributed. The number of bioactive BMSCs in mice DADM in EDTA group was 37±7, which was significantly more than that of mice DADM in Triton X-100 group (25±8, t =0.128, P <0.05). The proliferation of bioactive BMSCs in mice DADM in Triton X-100 group and EDTA group was similar at 2 hours and on day 1 after cultured ( t =1.292, 0.656, P >0.05). On 3, 5 days after cultured, the proliferation of bioactive BMSCs in mice DADM in EDTA group was significantly higher than that of mice DADM in Triton X-100 group ( t =2.309, 14.128, P <0.05 or P <0.01). Conclusions: Mice DADM prepared by decellularization of EDTA has better three-dimensional porous network structure and good continuity of collagen fiber. The BMSCs in bioactive DADM from burn mice prepared by transplanting BMSCs are evenly distributed with large quantity and strong proliferative capacity, which has the potential to be good autologous dermal substitute.

Objective: To report the use of implantable diaphragm pacer (IDP) in a patient with high cervical spinal cord injury(HCSCI). Methods: A 14-year-old male patient, who suffered from a HCSCI at C2 neurological level and had been on a ventilator for 2 years, received IDP in August 2017 at China Rehabilitation Research Center. A systematic literature review was performed on IDP in patients with HCSCI in Pubmed, CNKI, and Wanfang databases, using the keywords: phrenic nerve and electrical stimulation and spinal cord injury; IDP and spinal cord injury; breathing pacemaker system and spinal cord injury. All fields were covered from 1970/01/01 to 2018/01/01 in Pubmed, from 1981/01/01 to 2018/01/01 in CNKI, and from 1900/01/01to 2018/01/01 in Wanfang. Results: No spontaneous breathing was observed preoperatively in the patient. The electrical response of phrenic nerves was intact on the right, but unresponsive on the left. We got started with the IDP at 4 weeks after surgery. The threshold voltage of the right hemidiaphragm pacing was 0.1 V and at the level of 0.7 V with an optimal effect. No significant diaphragmatic contraction was found at left side with the extent up till 0.7 V. The maximum tidal volume was 840 ml when electrical stimulation was given at an intensity of 0.7 V bilaterally. The bilateral stimulation voltage at 0.1-0.2 V, pacing frequencies at 9 beats/min in bed, or at 12 beats/min on wheelchair, were set to maintain the tidal volume at the level of (435±32) ml. After 2-week adaptive training, the patient could wean from the ventilator for 12 hours and had a normal blood gas analysis. At 6 week after surgery, with the aid of IDP, the patient could get out in wheelchair for outdoor activities. By literature review, we found 78 English papers, including 6 clinical trials, 10 reviews, and 11 Chinese papers, consisting of 8 reviews, 1 study in animal, and 2 news reports. Extensive contents, such as preoperative evaluation, preoperative preparation, surgical procedures, complications, surgical outcomes, and animal model studies of IDP were involved. The indications of IDP reported by literature were: (1) central alveolar hypoventilation; (2) Sleep apnea syndrome (Biot's respiration); (3) Respiratory failure induced by brainstem injury or disease; (4) Respiratory failure induced by spinal cord injury or disease above C3 level. Conclusion: Our case study confirmed the therapeutic effect of IDP on patients with respiratory failure caused by HCSCI.

Primary hepatocellular carcinoma (PHC) is extremely common in eastern China, where it is both associated with chronic infection with hepatitis B virus (HBV) and often familial. Complex segregation analysis of 490 extended families was undertaken with liability classes defined by age, sex, and HBV infection status. The maximum-likelihood model suggests that a recessive allele with population frequency approximately .25 yields lifetime risk of PHC, in the presence of both HBV infection and genetic susceptibility, of .84 for males and .46 for females. The model further predicts that, in the absence of genetic susceptibility, lifetime risk of PHC is .09 for HBV-infected males and .01 for HBV-infected females and that, regardless of genotype, it is virtually zero for uninfected persons. Complex segregation analysis therefore provides evidence for the interaction of genotype, environmental exposure, sex and age in determining the occurrence of PHC in this population.

The epidemiological relationship between selenium level and age-adjusted human cancer mortality (incidence) was studied in 24 regions located in eight provinces of China. Statistically significant inverse correlation was found between age-adjusted total cancer death rates and selenium levels in whole blood from local residents. In the areas with high selenium levels, there was significantly lower mortality in both males and females from cancer of the stomach and esophagus. In addition, an inverse correlation between regional distribution of liver cancer incidence and selenium contents in blood and grains in Qidong county, an area with high risk of hepatoma, was observed. With the intention of providing selenium supplements to residents living in low selenium regions, the selenium content in grains was raised by means of foliar spraying of crops with Na2SeO3 solution.

A pedigree study was carried out in families with hepatocarcinoma (HCC) in Qidong county. The results showed that the incidence of families with familial history of HCC was 41.59% (443/1065). By means of test for Fitness of Binomial Distribution, it was found that HCC had an evident tendency of familial aggregation (P less than 0.01). In the high risk families, the average death age of patients with HCC in filial generation was younger (38.92 years old) than that of people who die of HCC in Qidong county (49.26 years old). The age at which siblings had HCC was often similar: 31.63%, with age-difference less than or equal to 2 years and 61.22%, less than or equal to 5 years. Whether the members of high risk families lived together or not, the incidence of HCC was alike (P greater than 0.05). These results suggest that the role of genetic factors in the etiology of HCC should not be neglected.

The selenium (Se) level in barley and maize from 43 communes of Qidong county, a high risk area of liver cancer in China, were assayed. An inverse correlation between the Se level and the liver cancer incidence was observed. An inverse correlation was also observed between the blood Se level and liver cancer incidence of the local residents. When selenite solution was sprayed on the crops during their preflowering, the content of Se in barley and maize was increased by 6 fold over the control. It is suggested that the increase of blood Se level of the residents who live in the low-Se areas by this method be useful in the prevention of liver cancer.