Paradoxical Embolic Stroke Following Percutaneous Transluminal Angioplasty in a Hemodialysis Patient.

Paradoxical embolism is a medical condition characterized by the migration of an embolus from a venous source into the systemic circulation. This occurs through a specific cardiac abnormality known as a right-to-left shunt, ultimately resulting in the possibility of arterial embolism. Patent foramen ovale (PFO) is the most common cause of intracardiac shunting. We reported a rare case of a 56-year-old man on hemodialysis with PFO and arteriovenous fistula dysfunction who suffered a paradoxical embolic ischemic stroke after percutaneous transluminal angioplasty. This case emphasized the potential risk of paradoxical embolism in hemodialysis patients with vascular access problems. We aimed to highlight the importance of searching for PFO, as it may serve as a possible source of embolism in these patients.

Do not stumble over the same "stone" twice: a case series of endogenous endophthalmitis secondary to severe systemic diseases.

BACKGROUND: Endogenous endophthalmitis (EE) is a rare but highly destructive eye emergency secondary to systemic infection. Acute endophthalmitis can lead to irreversible vision impairment or even loss of the whole eye, unless being diagnosed and treated promptly. CASE PRESENTATION: This study reports three typical EE cases of endogenous endophthalmitis secondary to different severe systemic diseases. Patients were recruited from the Department of ophthalmology at Zhongnan hospital of Wuhan University and the Department of ophthalmology at the Second Affiliated Hospital of Fujian Medical University. Patients were followed up for up to 60 days. Among these cases, the eye symptoms is the initial manifestations while secondary to original different special systemic conditions. Patients have been treated under dynamically prompt response undergoing systemic treatment and eye treatment at the same time. Best corrected visual acuity were 20/40, 20/60 and light perception during follow-up evaluation. CONCLUSIONS: Our observation suggest that prompt identification and treatment could save patients' vision from EE.

Association of CDK6 gene polymorphisms with Behcet's disease in a Han Chinese population.

Cyclin-dependent kinases 4/6 (CDK4/6) and D1-type cyclins (CCND1) can regulate the pro-inflammatory functions of various cytokines during the inflammatory response. This study investigated the association between CDK4/6-CCND1 variants and susceptibility in patients with Behcet's disease (BD). This case-control study enrolled 542 patients with BD and 754 healthy controls. Fourteen tagged single nucleotide polymorphisms (tag SNPs) of the CDK4/6-CCND1 gene were genotyped using the Sequenom MassARRAY system and iPLEX® Pro assay. The results indicated that the frequency of the CDK6 rs2282983 TT genotype was higher in the BD group than the control group (Pc = 0.040, OR = 1.408, 95% CI = 1.124-1.765), and CDK6 rs2282983 CT and rs42034 AG were negatively associated with BD (Pc = 3.647 × 10-4, OR = 0.598, 95% CI = 0.471-0.758; Pc = 0.039, OR = 0.626, 95% CI = 0.459-0.852, respectively). Furthermore, statistical analysis showed that CDK6 rs2282983 TT and CT genotypes were significantly associated with skin lesions in patients with BD (Pc = 0.042, OR = 1.436, 95% CI = 1.130-1.824; Pc = 0.001, OR = 0.594, 95% CI = 0.461-0.764, respectively). This study suggests that the CDK6 loci rs2282983 and rs42034 might confer genetic susceptibility to BD in a Han Chinese population, which could provide new insights into the pathogenesis of BD.

A Combination of Virulent and Non-Productive Phages Synergizes the Immune System against Salmonella Typhimurium Systemic Infection.

Effective phage cocktails consisting of multiple virus types are essential for successful phage therapy against pandrug-resistant pathogens, including Salmonella enterica serovar (S.) Typhimurium. Here we show that a Salmonella phage, F118P13, with non-productive infection and a lytic phage, PLL1, combined to inhibit pandrug-resistant S. Typhimurium growth and significantly limited resistance to phages in vitro. Further, intraperitoneal injection with this unique phage combination completely protected mice from Salmonella-induced death and inhibited bacterial proliferation rapidly in various organs. Furthermore, the phage combination treatment significantly attenuated the inflammatory response, restored the generation of CD4+ T cells repressed by Salmonella, and allowed macrophages and granulocytes to participate in immunophage synergy to promote bacterial clearance. Crucially, the non-productive phage F118P13 is less likely to be cleared by the immune system in vivo, thus providing an alternative to phage cocktail against bacterial infections.

Clinical Prediction of Surgical Revascularization Outcome in Moyamoya Disease Via Transcranial Color Sonography.

OBJECTIVE: Transcranial color-duplex sonography (TCCS) is a promising method in evaluating the hemodynamics in patients with moyamoya disease (MMD). This study aimed to explore the feasibility of preoperative TCCS in predicting the outcome of revascularization surgery in MMD patients. METHODS: We retrospectively analysed 64 cases of MMD patients receiving revascularization surgery from January 2012 to January 2014. We utilized TCCS to perform comprehensive hemodynamic examination on the hemodynamics of bilateral intracranial and extracranial cerebrovascular flow and assessed the surgical outcomes and prognosis through the longitudinal comparison of the preoperative and postoperative cerebrovascular hemodynamics. Occurrence of bypass blockage was regarded as surgical failure. RESULTS: We established a prediction model for bypass blockage among MMD patients with an AUC of 0.858 (95% CI: 0.666-1). The parameters, EDV of ECA and PSV of MA obtained by the model are the main preoperative predictors for bypass blockage. CONCLUSIONS: TCCS could preoperatively determine the degree of MMD and evaluate the outcome of revascularization surgery. It also is a feasible tool to predict the curative effect by providing preoperative hemodynamic information.

NR4A1 silencing protects against renal ischemia-reperfusion injury through activation of the ß-catenin signaling pathway in old mice.

Renal ischemia-reperfusion injury (IRI), a major cause of acute kidney injury as well as a contributor to a rapid kidney dysfunction and high mortality rates, is a complex yet not fully understood process. Investigation on the underlying molecular mechanism including the inflammation initiation and progression can help to have a better understanding of the disease, and thereby lead to a potential therapeutic approach. We established renal IRI mouse model groups differing in their ages. These renal IRI mice were treated either only with si-nuclear receptor subfamily 4, group A, member 1 (NR4A1) or together with si-ß-catenin by tail vein injection to analyze the role of NR4A1 and ß-catenin in the development of renal IRI. Serum creatinine (SCr) and blood urea nitrogen (BUN) levels were examined for renal function analysis. Levels of the apoptosis markers B-cell lymphoma-2 (Bcl-2), Bcl-2 associated protein X (Bax), and cleaved caspase-3 were determined. NR4A1 gene was up-regulated in the renal tissues of all mice with IRI, which showed a much higher level in the old mice with IRI. si-NR4A1 treatment resulted in reduced SCr and BUN levels and a decrease of cell apoptosis, indicated by lower expression of Bax and cleaved Caspase-3, while in contrast increased levels of Bcl-2 were detected. Interestingly, also the ß-catenin level was increased by knockdown of NR4A1. Furthermore, si-ß-catenin reversed the effect of knockdown of NR4A1, leading to aggravated renal function damage, severe pathological injury and increased apoptosis. Thus, silencing NR4A1 ameliorates renal IRI via ß-catenin signaling pathway activation. Down-regulated NR4A1 confirms renoprotective properties against renal IRI via the activation of ß-catenin signaling pathway in old mice.

Heparin-free continuous vena-venous hemofiltration as a veno-venous bypass in inferior vena cava reconstruction.

OBJECTIVE: This paper investigated the effects of continuous vena-venous hemofiltration on inferior vena cava reconstruction. METHOD: Totally, 11 patients were observed, vascular access in right internal jugular vein and femoral vein catheterization was established guided by ultrasound, and heparin-free continuous vena-venous hemofiltration was used to substitute for extracorporeal veno-venous bypass. Furthermore, blood pressure, central venous pressure, urine volume, blood platelet, serum albumin, renal function, serum cystatin C, CRP, TBil, AST, ALT, serum amylase, serum lipase, PLT, PT, APTT, Fig, D-mier, and adverse events were determined. RESULTS: All operations were completed successfully. Average time of continuous vena-venous hemofiltration was 2.96 ± 0.76 h. No hematoma and blood leakage was occurred when catheters were inserted, and no luminal stenosis and catheter-related infections were observed. Visceral congestion was observed when the inferior vena cava was clamped, but significantly improved immediately after the continuous vena-venous hemofiltration was begun. No hemofilter was changed due to clotting during continuous vena-venous hemofiltration therapy. Blood pressure, central venous pressure, and urine volume of the patients maintained stable. No significant change was observed in blood platelet, serum albumin, and serum creatinin. Serum cystatin and hsCRP increased after operation, but still in normal level. CONCLUSION: Heparin-free continuous vena-venous hemofiltration was an effective mode as veno-venous bypass in the treatment of inferior vena cava interruption and reconstruction.

[Spectrophotometric determination of aromatic amino compounds with J-acid].

The problems such as chromogenic reaction selectivity, reaction rate, sensitivity and water-solubility of azo compounds were considered. The molecular structures of coupling components were theoretically designed and screened in the present research The reaction conditions and methods of chromogenic reaction were investigated. J-Acid (2-amino-5-naphthol-7-sulfonic acid) as a coupling reagent to determine aromatic amino compounds was established. In the presence of potassium bromide, at room temperature, nitrite reacted with aromatic amino compounds in the medium of thin hydrochloric acid. Then diazonium salt reacted with J-Acid in the aqueous solution of sodium carbonate, forming coloured azo dye, which had a maximum adsorption at 480 nm. The molar adsorption coeffcients of aniline, 4-aminobenzene sulfonic acid and 1-naphthylamine were 3. 95 X 10(4), 3. 24 X 10(4) and 3. 91 X 10(4) L . mol-1 . cm-1 , respectively. Experimental results showed that common coexisting ions on the surface water did not affect the results of determination. J-Acid of spectrophotometry was used to determine the samples of Shanghai Fu Xing Dao canal. Meanwhile, recovery experiments by standard addition method were done. Experiment results showed that the recoveries of aniline were in the range of 98. 5%-102. 1%, and RSD was 2. 08%. J-Acid is a common organic reagent. It is soluble in water and low volatile, and its toxicity is much lower than N-ethylenediamine. spectrophotometric determination of aromatic amino compounds by J-Acid has the advantage of high sensitivity, good selectivity, simple rapid operation and accurate results, and thus it can be used for the determination of trace aromatic amino compounds in the environmental water.

Intermittent sliding-lock-knot suture for limbal conjunctival autograft fixation in pterygium surgery: a technique note.

AIM: To report a technique used with intermittent sliding-lock-knot (ISLK) fixation for limbal conjunctival autografts in pterygium surgery and compared with those of routine intermittent (RI) fixation. METHODS: Consecutive patients with primary pterygium who had undergone pterygium excision combined with limbal conjunctival autograft transplantation between March 2021 and March 2022 at our institute were retrospectively analyzed. Primary outcome measures were mean duration of surgery and suture removal, degree of conjunctival hyperemia on postoperative day 1, pain score at suture removal, postoperative symptoms at 6mo, including conjunctival hyperemia, foreign body sensation, and graft stability. RESULTS: Ninety-eight patients underwent monocular surgery and were divided into ISLK (51 eyes) and RI (47 eyes) groups according to the type of conjunctiva autograft fixation method planned. There was no significant difference in mean duration of surgery between the two groups (18.59±2.39min vs 18.15±2.20min, P=0.417); however, compared to the RI group, shorter suture removal times were observed in the ISLK group [0.58min (0.42-0.87) vs 3.00min (2.21-4.15), P<0.001]. The degree of conjunctival hyperemia on postoperative day 1 was milder in the ISLK group (P<0.001). Pain scores at suture removal were lower in the ISLK group than in RI group [1 (0-3) vs 2 (1-4), P<0.001]. Postoperative symptoms at 6mo were comparable between the groups (P=0.487), with no recurrence. CONCLUSION: ISLK is an innovative method for limbal conjunctival autograft fixation after pterygium excision. Compared to RI fixation, ISLK facilitates suture removal and reduces discomfort, with comparable surgery duration and less conjunctival hyperemia.

Comparative Analysis between Salmonella enterica Isolated from Imported and Chinese Native Chicken Breeds.

Salmonella enterica is considered a significant threat to the global poultry industry and public health. In recent decades, antimicrobial resistance in Salmonella enterica has attracted increasing concern throughout the world. However, limited information is available on Salmonella enterica among different breeds of breeder chickens. Thus, this study aimed to compare the prevalence, serotype distribution, emergence of extended-spectrum beta-lactamases (ESBLs), antimicrobial resistance, and genetic resistance mechanisms in Salmonella enterica among different breeds of breeder chickens. A total of 693 samples (dead embryos, cloacal swabs, water, feed, environmental swabs, and meconium of newly hatched chicks) were selected and cultured for Salmonella from four breeder chicken farms in Shandong province, China, representing one imported and three native breeds, and the isolates were further serotyped. Of the Salmonella isolates, susceptibility to 11 antimicrobials of 5 classes, ESBL screening, and the presence of 21 antimicrobial resistance genes were determined in the present study. Overall, 94 (13.6%) isolates were recovered, which were divided into 3 serotypes (Salmonella Pullorum (n = 36), Salmonella Thompson (n = 32), and Salmonella Enteritidis (n = 26)). The results showed that the prevalence of Salmonella enterica isolates from the imported breeds was higher compared with the three domestic breeds. Eight of the ninety-four isolates were ESBL-positive strains, which were recovered from a domestic breed chicken farm. These eight ESBL-producing isolates were serotyped to Pullorum. Surprisingly, Salmonella Enteritidis (S. enteritidis) and S. pullorum were simultaneously isolated from a single dead embryo observed among one native breed. Meanwhile, among the Salmonella isolates, 53.2% (50/94) were multidrug-resistant strains, and 44.7% (42/94) of the isolates presented resistance to at least five antibiotics. Nearly all of the isolates (97.9%, 92/94) were resistant to at least one antimicrobial; one isolate of S. Thompson was resistant to seven antimicrobial agents belonging to four different classes. The carriage rate of three resistance genes (tetA, tetB, and sul1) among isolates from the imported breeds (87%, 70%, and 65.2%) was higher than that in those from domestic breeds (35.2%, 36.6, and 14.1%). To our knowledge, this is the first report of ESBLs-producing Salmonella isolated from a Chinese native breed of breeder chickens. Our results also highlight that a high prevalence of multidrug-resistant Salmonella enterica contamination is widespread among different breeds of breeder chickens, which is a major risk of food-borne diseases and public health.

Circ_0000033 up-regulates NUAK2 by sequestering miR-378a-3p to promote breast tumorigenesis.

Circular RNAs (circRNAs), including circ_0000033, were shown to be abnormally expressed in breast cancer (BC) and play an important regulatory function in the development of this cancer. This study aimed to investigate the action and mechanism of circ_0000033 in BC carcinogenesis. Specifically, levels of genes and proteins were analyzed using quantitative real-time PCR (qRT-PCR) and western blotting. Circ_0000033 was highly expressed in BC tissues and cells. Properties of cells with modified expression of circ_0000033 were characterized using an in vitro colony formation assay, EdU assay, flow cytometry, caspase-3 activity analysis, transwell assay, and tube formation assay, respectively. Functionally, knockdown of circ_0000033 suppressed BC cell proliferation, migration, invasion, angiogenesis, and induced apoptosis and cell cycle arrest in vitro. An in vivo experiment was conducted using a murine xenograft model and showed circ_0000033 silencing also impeded the growth of BC in nude mice. The binding between miR-378a-3p and circ_0000033 or NUAK2 (NUAK Family Kinase 2) was validated using a dual-luciferase reporter assay. Circ_0000033 sequestered miR-378a-3p and resulted in NUAK2 release, indicating a circ_0000033/miR-378a-3p/NUAK2 regulatory network operates in BC cells. Circ_0000033 down-regulation in BC cells was accompanied by decreased NUAK2 and increased miR-378a-3p expression. Moreover, the anticancer effects mediated by circ_0000033 knockdown were abolished by miR-378a-3p inhibition or NUAK2 overexpression in BC cells. Overall, circ_0000033 up-regulates NUAK2 through sequestration miR-378a-3p, which promoted breast tumorigenesis, suggesting circ_0000033 is a promising therapeutic target for BC treatment.

Studies on the adsorption of sulfo-group-containing aromatics by chitosan-ß-cyclodextrin.

Chitosan-ß-cyclodextrin (CTS-CD) prepared through a crosslinking reaction between chitosan and ß-cyclodextrin was employed to adsorb the three following sulfo-group-containing aromatics: disodium 2-naphthol-3,6-disulfonate (R salt), 2-naphthalene sulfonic acid (NSA), and sodium dodecylbenzene sulfonate (SDBS). At 318 K, the saturated adsorption capacity of CTS-CD for R salt, NSA, and SDBS was 431, 416, and 376 mg/g, respectively. The experimental data fitted the second-order model well and the rate constant of the adsorption increased with the temperature increment. The values of apparent activation energy for R salt, NSA, and SDBS were calculated as 33.2, 34.2, and 16.8 kJ/mol respectively. The isothermal adsorption was found following the Langmuir adsorption equation. The negative values of ΔG and the positive values of ΔH indicated that the adsorption process was spontaneous and exothermic.

Synthesization, characterization and adsorption properties of sulfonic cellulose.

The synthesization and characterization of a new environmental functional material-sulfonic cellulose - were studied in this paper. The preparation conditions were optimized through an orthogonal experiment. The modified cellulose was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM). The adsorption rules of cationic organic pollutants and heavy metal ions by this new material were discussed. Regeneration and recycling performances of the sulfonic cellulose were also investigated. At the temperature of 323 K, sulfonic cellulose was prepared by grafting 2-acrylamido-2-methylpropane sulfonic acid (AMPS) onto alkali-treated cellulose for 4 h with the employing of ceric ammonium nitrate as initiator. The mass ratio of AMPS to cellulose was 3:1 and the concentration of ceric ammonium nitrate was 63.8 mmol/L. The sulfur content of sulfonic cellulose was 7.32 wt%. The peaks of 1,303 and 1,159 cm⁻¹ in IR suggested the existence of the sulfonic group in sulfonic cellulose. The XRD and SEM results showed that the crystallinity decreased while the specific surface area increased after modification. Batch adsorption results showed that sulfonic cellulose had a favorable adsorption capacity for model contaminants at pH 6.0-7.0. The adsorption process was endothermic and reached equilibrium in 180 min. The adsorption rules of cationic organic pollutants and heavy metal ions indicated that sulfonic cellulose had high adsorption capacity for the cationic dyes with a coplanar macromolecule structure and organic compounds carrying the amino group. Under room temperature, 1.0 mol/L HCl can be used as a desorption solution and the equilibrium adsorption capacity had little decrease (less than 7%) after six adsorption-desorption cycles.

Airway Management in Adult Intensive Care Units: A Survey of Two Regions in China.

The critical medicine residency training in China started in 2020, but no investigation on the practice of tracheal intubation in ICUs in China has been conducted. A survey was sent to the adult ICUs in public hospitals in Shenzhen (SZ) city and Xinjiang (XJ) province using a WeChat miniprogram to be completed by intensive care physicians. It included questions on training on intubation, intubation procedures, and changes in the use of personal protective equipment due to COVID-19. We analyzed 301 valid questionnaires which were from 72 hospitals. A total of 37% of respondents had completed training in RSI (SZ, 40% vs. XJ, 30%; p = 0.066), and 50% had participated in a course on the emergency front of the neck airway (SZ, 47% vs. XJ, 54%; p = 0.256). Video laryngoscopy was preferred by 75% of respondents. Manual ventilation (56%) and noninvasive positive pressure ventilation (34%) were the first-line options for preoxygenation. For patients with a high risk of aspiration, nasogastric decompression (47%) and cricoid pressure (37%) were administered. Propofol (82%) and midazolam (70%) were the most commonly used induction agents. Only 19% of respondents routinely used neuromuscular blocking agents. For patients with difficult airways, a flexible endoscope was the most commonly used device by 76% of respondents. Most participants (77%) believed that the COVID-19 pandemic had significantly increased their awareness of the need for personal protective equipment during tracheal intubation. Our survey demonstrated that the ICU doctors in these areas lack adequate training in airway management.

CHST7 Methylation Status Related to the Proliferation and Differentiation of Pituitary Adenomas.

Pituitary adenomas (PAs) are the second most common primary brain tumor and may develop from any of the cell lineages responsible for producing the different pituitary hormones. DNA methylation is one of the essential epigenetic mechanisms in cancers, including PAs. In this study, we measured the expression profile and promoter methylation status of carbohydrate sulfotransferase 7 (CHST7) in patients with PA; then, we investigated the effect of the CHST7 methylation status on the proliferation and differentiation of PAs. The volcano map and Metascape results showed that the levels of CHST7 were related to the lineages' differentiation and the cell adhesion of PAs, and patients with low CHST7 had greater chances of having an SF-1 lineage (p = 0.002) and optic chiasm compression (p = 0.007). Reactome pathway analysis revealed that most of the DEGs involved in the regulation of TP53 regulated the transcription of cell cycle genes (HSA-6791312 and HSA6804116) in patients with high CHST7. Correlation analysis showed that CHST7 was significantly correlated with the eIF2/ATF4 pathway and mitochondrion-related genes. The AUC of ROC showed that CHST7 (0.288; 95% CI: 0.187-0.388) was superior to SF-1 (0.555; 95% CI: 0.440-0.671) and inferior to FSHB (0.804; 95% CI: 0.704-0.903) in forecasting the SF-1 lineage (p < 0.001). The SF-1 lineage showed a higher methylation frequency for CHST7 than the Pit-1 and TBX19 lineages (p = 0.009). Furthermore, as the key molecule of the hypothalamic-pituitary-gonadal axis, inhibin ßE (INHBE) was positively correlated with the levels of CHST7 (r = 0.685, p < 0.001). In summary, CHST7 is a novel pituitary gland specific protein in SF-1 lineage adenomas with a potential role in gonadotroph cell proliferation and lineage differentiation in PAs.

MiR-17 and miR-93 Promote Tumor Progression by Targeting p21 in Patients with Chordoma.

OBJECTIVE: MicroRNAs have been implicated in the progression of various cancers. However, the role of microRNAs in chordoma remains to be further elucidated. Here, we purposed to character the role of two microRNAs, miR-17 and miR-93, and their potential mechanisms in chordoma. METHODS: The expression and prognostic value of miR-17 and miR-93 were assessed by the quantitative real-time polymerase chain reaction, Kaplan-Meier survival curve, and Cox regression analysis. The effects of miR-17/93 mimics on chordoma cell proliferation, colony formation, and invasion were analyzed by CCK-8 assay, colony formation assay, and transwell assay. The downstream target of miR-17/93 was further explored via luciferase reporter assay. RESULTS: High expression of miR-17/93 was identified in chordoma tissues, and was associated with poor prognosis. Overexpression of miR-17/93 contributed to cell proliferation, colony formation, and invasion. Mechanistically, we demonstrated that miR-17/93 directly targeted p21 and decreased the expression of p21. Besides, the rescue assay further confirmed the essential role of the miR-17/93-p21 axis in chordoma. CONCLUSION: Our results revealed the potential oncogenic effect of the miR-17/93 on chordoma progression, and suggested that the miR-17/93-p21 axis served as a promising therapeutic target in chordoma.

One-stop hybrid surgery for treatment of complex Stanford type B aortic dissection.

OBJECTIVES: To compare the efficacy and prognosis of one-stop hybrid surgery using the elephant trunk procedure for treatment of complex Stanford type B aortic dissection. METHODS: We retrospectively analyzed patients who underwent surgical treatment from January 2014 to July 2019. The patients were divided into those who underwent the elephant trunk procedure (n = 10) and those who underwent one-stop hybrid surgery (n = 10). The cardiopulmonary bypass time, mechanical ventilation time, length of hospital stay, and red blood cell usage were compared between the two groups. All patients' 3-month postoperative aortic computed tomography angiography (CTA) findings were also reviewed. RESULTS: The cardiopulmonary bypass time, mechanical ventilation time, and length of hospital stay were significantly shorter and red blood cell usage was significantly lower in the one-stop hybridization group. The aortic cross-clamp time was not significantly different between the two groups. Aortic CTA review after hybrid surgery showed that the true lumen of the descending aorta was almost completely restored at 3 months. CONCLUSION: One-stop hybrid surgery effectively alleviated the occlusion of the aortic dissection, prevented the need for additional surgery, and expanded the indications for covered-stent endovascular repair.

Durable Defect Passivation of the Grain Surface in Perovskite Solar Cells with π-Conjugated Sulfamic Acid Additives.

Defect passivation has shown an essential role in improving the efficiency and stability of perovskite solar cells (PSCs). Herein, an efficient and low-cost π-conjugated sulfamic acid additive, 4-aminobenzenesulfonic acid (4-ABSA), is used to realize durable defect passivation of PSCs. The incorporation of 4-ABSA not only constructs a compact and smooth perovskite film but is also capable of passivating both negative- and positive-charged defects derived from under-coordinated lead and halogen ions. Besides, the π-conjugated system in 4-ABSA can induce preferred perovskite crystal orientation and stabilize the coordination effect between 4-ABSA and perovskite grains. As a result, the inverted planar PSC incorporated with 4-ABSA additives demonstrates an improved power conversion efficiency (PCE) from 18.25 to 20.32%. Moreover, this 4-ABSA passivation agent also enhances the stability of devices, which retains 83.5% of its initial efficiency under ambient condition at 60 °C after 27 days. This work provides a π-conjugated sulfamic acid for durable defect passivation of perovskite optoelectronic devices.

Controllable nanoreactor confined to atomic force microscopy tips and its application in low copy DNA ligation.

Less molecules reaction, especially at the single molecule level, plays an important role in biochemical or chemical research. It is also significant to achieve low copy or single molecule DNA ligation during the whole genome project. In this paper, a new type of nanoreactor was constructed around atomic force microscopy (AFM) tips under certain humidity, where DNA molecules can be limited to a special space through water meniscus, so the probability of molecules collision was increased and the efficiency of DNA ligation was greatly enhanced. Combined with the nanomanipulation based on AFM, controllable nanoreactor may provide a new tool to single molecule reaction. Low copy DNA ligation was successfully achieved by this method. Results showed the number of DNA molecules involved in the nanoreactor can not be more than sixty. This method will found a base for the ultimate realization of single-molecule DNA ligation.

Kinetic and thermodynamic studies on the adsorption of anionic surfactant on quaternary ammonium cationic cellulose.

Removal of anionic surfactants from aqueous solutions by adsorption onto quaternary ammonium cationic cellulose (QACC) was investigated. The effects of solution acidity, initial concentration, adsorption time, and temperature on the adsorption of sodium dodecyl-benzene sulfonate (SDBS), sodium lauryl sulfate (SLS), and sodium dodecyl sulfonate (SDS) were studied. The kinetic experimental data fit well with the pseudo-second-order model; the rate constant of the adsorption increased with temperature. The values of apparent activation energy for the adsorption were calculated as ranging from 10.2 to 17.4 kJ/ mol. The adsorption isotherm can be described by the Langmuir isotherm. The values of thermodynamic parameters (deltaH0, deltaS0, and deltaG0) for the adsorption indicated that this process was spontaneous and endothermic. At 318 K, the saturated adsorption capacities of QACC for SDBS, SLS, and SDS were 1.75, 1.53, and 1.39 mmol/g, respectively. The adsorption process was mainly chemisorption and partially physisorption. The results show that QACC is effective for the removal of anionic surfactants.