Three types of bidirectional leader development in triggered lightning flashes.

Eight cases of bidirectional leader (BL) development in artificially triggered lightning flashes are reported with synchronous high-speed camera images and electric field signals. Based on optical progressing characteristics, the eight cases can be divided into three types: a reflection type, a discontinuity type, and an inducement type. For the reflection type, the tail of a dart leader may begin to extend backward when the leader's head reaches a branch point, or the top of the exploded triggering wire. For the discontinuity type, the initiation of a bidirectional leader below a decayed attempted leader may occur more than once preceding one return stroke. For the inducement type, the approach of another leader with the same polarity will turn a dart leader into a bidirectional leader. The reflection type and inducement type are first observed here. Two cases of the discontinuity type are observed, and both are multiple-bidirectional leaders observed for the first time. For the reflection type and inducement type, there are fluctuations in the electric field related to the BL development. The dissipation of the downward leader slows down the negative increase of the electric field. Once the BL development starts, the downward negative end of the BL moves towards the ground with the E-field negatively increasing. For the discontinuity type, the close electric field result shows no fluctuations. The BL development has a much longer duration than the other two BL types.

Transabdominal preperitoneal versus hybrid procedures for treating irreducible inguinal hernias: A retrospective controlled study.

BACKGROUND: Inguinal hernia is a common condition; however, irreducible inguinal hernias are rare. In this retrospective study, two laparoscopic procedures for irreducible inguinal hernia were compared. MATERIALS AND METHODS: The study cohort comprised 88 patients who had undergone laparoscopic repair of primary irreducible inguinal hernias between 1 June 2011 and 31 December 2019. The patients were retrospectively divided into Hybrid (Group H) and Standard Transabdominal Preperitoneal (TAPP) Groups (Group S). Patient characteristics, hernia details, and intraoperative and postoperative complications were compared between study groups. RESULTS: There were no significant differences between the two groups in baseline characteristics, including age, sex, body mass index, hernia type, operation time, hospital stay, cost, and duration of follow-up. No recurrence or surgical site infection occurred in either group. There were no significant differences between the two groups in incidence of spermatic vessel injury (0% vs. 2.04%, P = 0.370), vas deferens injury (0% vs. 6.12%, P = 0.116), epigastric vessels injury (0% vs. 4.08%, P = 0.202), scrotal hematoma (7.69% vs. 2.04%, P = 0.206), dysuria (5.13% vs. 8.16%, P = 0.575), fever (17.95% vs. 16.32%, P = 0.841), seroma (25.64% vs. 32.65%, P = 0.474), chronic pain (0% vs. 2.04%, P = 0.370), sensation of a foreign body (2.56% vs. 2.04%, P = 0.870), or pain on ejaculation (0% vs. 2.04%, P = 0.370). The incidence of acute pain was higher in Group H than in Group S (43.59% vs. 8.16%, P = 0.000). CONCLUSION: The hybrid TAPP procedure is a safe and feasible means of treating irreducible inguinal hernias. Though it is associated with a higher incidence of postoperative acute pain than the standard TAPP procedure, it may have advantages in avoiding injuries to the vas deferens and spermatic vessels.

AURKA, as a potential prognostic biomarker, regulates autophagy and immune infiltration in nasopharyngeal carcinoma.

BACKGROUND: Dysfunction of Aurora A (AURKA) plays crucial role in tumorigenesis and development of many types of cancer. However, the role of AURKA in nasopharyngeal carcinoma (NPC) has not been investigated yet. MATERIALS AND METHODS: Two independent NPC cohorts (GSE61218 and GSE102349) were enrolled from public database to investigate the expression level of AURKA between NPC and nasopharyngitis samples, the association of AURKA expression level with prognosis in NPC, and the potential mechanism of AURKA in NPC by using bioinformatics analyses. The expression level of AURKA protein in 62 paired NPC and nasopharyngitis tissues was evaluated by immunohistochemistry (IHC). Two NPC cell lines (SUNE-1 and CNE-2) were enrolled and the expression levels of AURKA in the NPC cells were inhibited by RNA interference. The expression levels of mRNAs were tested by qPCR and western-blotting. CCK-8 assay was applied to measure the cell growth. Cell migration was measured by using wound healing assays. RESULTS: AURKA was highly expressed in NPC samples compared to nasopharyngitis samples in GSE61218, which was confirmed by IHC. High expression of AURKA was associated with worse prognosis in GSE102349. Notably, silencing of AURKA was associated with significantly decreased cell growth and migration in NPC. Moreover, we found that the differentially expressed genes between high and low AURKA expression groups in GSE102349 were majorly enriched in both autophagy-related and immune-related pathways. Additionally, the expression level of AURKA was associated with the expression levels of autophagy-related genes and the infiltration of immune cells. CONCLUSION: AURKA overexpressed in NPC, which was associated with poor prognosis. Silencing of AURKA inhibited the proliferation and migration of NPC cells. Besides, AURKA might participate in the regulation of both autophagy and immunity in NPC.

Induction chemotherapy with sequential nimotuzumab plus concurrent chemoradiotherapy in advanced nasopharyngeal carcinoma: A retrospective real-world study.

Many locally advanced nasopharyngeal carcinoma patients develop local recurrence or distant metastasis. Our retrospective real-world study aims to evaluate the efficacy and safety of curative sequential approach with induction chemotherapy followed by concurrent chemoradiation + nimotuzumab as first-line therapy in advanced nasopharyngeal carcinoma. From 2015 to 2021, the clinic data of 117 patients with advanced nasopharyngeal carcinoma (stage III-IV a) who were treated in the Affiliated Hospital of Guangdong Medical University were retrospectively reviewed. Fifty-four patients in observation group received taxanes, cisplatin, and 5-fluorouracil/taxanes and cisplatin induction chemotherapy and nimotuzumab (200 mg, weekly) combined with concurrent chemo-radiotherapy (cisplatin: 40 mg/m2 weekly; intensity-modulated radiation therapy); 63 patients in control group received same therapy without nimotuzumab. There was no significant difference in patients' characteristic baseline between 2 groups (P > .05). The complete response rate and objective response rate of the observational group was significantly higher than control group (46.30% vs 17.64%, P = .01; 96.30% vs 82.54%, P = .02). The median follow-up time was 24.77 (3.53-65.97) months. Both of the median progress free survival time and overall survival time were not reached. The 5-year progression-free survival rate of observation group was greater than control group (84.40% vs 63.70%, hazard ratios 0.365, 95% confidence intervals 0.147-0.909, P = .03). The 5-year overall survival rate of observation group and control group were 91.70% and 84.60%, respectively (P = .20). None of the patients withdrew from the study due to adverse events. Nimotuzumab combined with concurrent chemoradiotherapy as first-line therapy in advanced nasopharyngeal carcinoma can improve objective response rate and 5-year progress free survival rate with good safety profile.

Treatment of mesh infection after inguinal hernia repair: 3-year experience with 120 patients.

PURPOSE: Mesh infection is a devastating complication of sterile hernia repair surgery. This study was performed to assess the short- and long-term outcomes following treatment for mesh infection after inguinal hernia repair. METHODS: This single-center retrospective study included all patients who developed mesh infection after inguinal hernia repair from January 2018 to December 2020. Patient demographics, mesh infection characteristics, microbiology, features of surgery, short- and long-term outcomes, and follow-up data were analyzed. RESULTS: In total, 120 patients (8 women, 112 men; mean age, 54.4 years; mean body mass index, 24.8 kg/m2) were treated for mesh infection. The cultures were positive in 88 patients; 62.5% of these were positive for Staphylococcus aureus. Laparoscopic exploration was performed in 108 patients. Seventy patients underwent complete removal of infected mesh, and 50 underwent partial removal. During the short-term follow-up, 11 patients developed a minor wound infection and were treated with dressings and antibiotics, 1 developed a wound infection requiring debridement, 30 developed seromas, and 3 developed hematomas that did not require surgical intervention. During the mean follow-up of 39.1 months, 4 patients developed hernia recurrence, 2 experienced chronic pain, and 23 developed recurrent infection requiring reoperation in the partial mesh removal group (in contrast, only 4 patients in the complete mesh removal group developed recurrent infection, with a statistically significant difference). CONCLUSION: The outcome of mesh infection after inguinal hernia repair treated by mesh removal is satisfactory. Systematic individualized treatment by experienced experts based on the patient's previous repair technique, implanted mesh, and physical condition is recommended.

Ascorbic acid-induced fiber-scrolling of titanium carbide Ti3C2T x MXene.

Changing the morphology of two-dimensional materials often offers an efficient and effective means to exploit their electronic and mechanical properties. Two-dimensional materials such as graphene can be scrolled into one-dimensional fibers via simple sonication. Unfortunately, scrolling MXene nanosheets into fibers is quite challenging, especially Ti3C2T x composed of three layers of titanium atoms and two layers of carbon atoms. Herein, we report a new method to fabricate MXene fibers via ascorbic acid (AA) induced scrolling of Ti3C2T x nanosheets. An unusual AA-Ti3C2T x interaction is discovered in that intercalated AA molecules bind to and interact with the Ti3C2T x surface in the form of a hydrogen bonding-bonded assembly instead of as individual molecules, and a sheet-scrolling mechanism is proposed based on this interaction. The as-obtained MXene fibers exhibit a compact cross-section, and the diameter can be tailored from hundreds of nanometers to several micrometers through tuning the MXene/AA ratio. Moreover, the storage modulus of the MXene-fiber sponge attains its maximum value of ∼1 MPa when a unique morphology comprising both fibers and not-yet-scrolled sheets is presented. This work offers a new strategy of fiber-shaping MXenes for applications in structural composites and flexible electronics.

Cell Division Cycle-Associated Genes Are Potential Immune Regulators in Nasopharyngeal Carcinoma.

BACKGROUND: Cell division cycle-associated (CDCA) gene family is essential to cell cycle regulation. Numerous studies have illuminated that dysfunction of CDCA genes may not only lead to uncontrolled cell proliferation resulting in tumorigenesis but also influence immune cell infiltration in tumors. However, the role of the CDCA gene family on the prognosis and immune infiltration in nasopharyngeal carcinoma (NPC) remains to be unclear. METHODS: SBC human ceRNA array V1.0 was used to measure mRNA expression in three pairs of NPC tissues and nasopharyngitis tissues. The expression of CDCA8 was confirmed in an IHC microarray containing 130 NPC patients. Two external GEO cohorts were enrolled for further analysis. Prognosis analysis was performed using the Kaplan-Meier method. Gene set enrichment analysis (GSEA) was applied to explore the potential mechanism of CDCA genes in NPC. The relationship between CDCA gene family and immune infiltration in NPC was evaluated using the Xcell tool. RESULTS: CDCA genes were broadly upregulated in NPC tissues compared to nasopharyngitis tissues, and high expression of CDCA3/5/8 indicated worse prognosis in NPC. Besides cell cycle pathways, we found that CDCA3/5/8 were involved in multiple immune-related pathways. Overexpression of CDCA8 was strongly associated with less infiltration of CD8+ T cells and more infiltration of CD4+ Th1 cells and was negatively correlated with immune checkpoint blockade (ICB)-related genes. CONCLUSION: CDCA gene family was upregulated in NPC, and their expressions were associated with adverse prognosis. High expression of CDCA8 was associated not only with poor prognosis, but also with less immune infiltration and downregulation of ICB-related genes in NPC.

Rationale and design of a prospective, multicenter, randomized controlled trial of postoperative venous thromboembolism prophylaxis in Chinese adult patients with inguinal hernia (CHAT-3 trial).

BACKGROUND: Venous thromboembolism (VTE) is one of the most common causes of preventable harm for patients in hospitals. Nearly half of all VTE events was estimated to occur after surgical procedure. The Caprini risk score is the most extensively used risk assessment tool in predicting postoperative VTE, which is too complicate for surgeons to use properly in their clinical practice. METHODS: The CHAT-3 trial will be a prospective, multicenter, randomized, parallel-group trial, which is designed to identify patients at moderate or high risk of VTE after inguinal hernia surgery using the previously established three-factor model, and to use low molecular weight heparin (LMWH) for VTE prevention, in comparison to the current routine assessment and practice used in those patients. Totally, 1,008 patients planned to undergo inguinal hernia surgery will be enrolled, with cluster randomization at 1:1 ratio into intervention arm and control arm. The primary outcomes are the accordance of perioperative VTE prophylaxis based on current guidelines and the rate of pharmacological prophylaxis for VTE. The secondary outcomes are the occurrences of perioperative VTE, major bleeding, mortality of patients after inguinal hernia surgery, and trend of D-dimer during the follow-up period. DISCUSSION: This study will create evidence that whether the administration based on a simple model is of efficacy and safety for VTE prophylaxis among Chinese patients underwent inguinal hernia surgery. TRIAL REGISTRATION: The CHAT-3 trial (Trial registration number: ChiCTR2000033769).

Preperitoneal herniation as a complication of tansabdominal preperitoneal patch plasty: a report of two cases.

BACKGROUND: Preperitoneal herniation is a rare complication after transabdominal preperitoneal patch plasty (TAPP) and may be caused by inadequate peritoneal closure. We herein report two cases of postoperative small bowel obstruction due to preperitoneal herniation through a disrupted peritoneum. CASE PRESENTATION: Two men in their 70s were admitted to our center because of small bowel obstruction after TAPP. After examinations and unsuccessful conservative treatment, emergency laparoscopic exploration was performed. Preperitoneal herniation through the disrupted peritoneum was found. The herniated small bowel was reduced and the peritoneum was properly reclosed. The patients recovered and were discharged with normal bowel function. CONCLUSIONS: Inadequate peritoneal closure may cause preperitoneal herniation and lead to postoperative small bowel obstruction and even death. Hernia surgeons can avoid this complication by improving their suture technique and paying attention to the procedure details.

Clinical value of the laparoscopic transabdominal preperitoneal technique in recurrent inguinal hernia repair.

OBJECTIVE: To assess the clinical value of the laparoscopic transabdominal preperitoneal (TAPP) technique in recurrent inguinal hernia repair. METHODS: The clinical data of 354 patients with recurrent inguinal hernia who underwent TAPP surgery from June 2010 to June 2016 at the Department of Hernia and Abdominal Wall Surgery, Beijing Chaoyang Hospital, Capital Medical University, were retrospectively analyzed. RESULTS: Laparoscopic surgery was successfully completed in all 360 patients. Among them TAPP were finished in 354 patients, while TAPP repair were attempted but finally converted to open or TAPE repair in 6 patients. The mean operation time was 54.7 ± 19.4 min (range 30-90 min), mean duration of hospitalization was 4.7 ± 2.1 days (range 2-14 days), and mean duration of follow-up was 37.7 ± 12.4 months (range 12-60 months). The rate of intraoperative injury was 4.5% (16/354), and the rate of postoperative complications was 13.6% (48/354). No patient developed a foreign body sensation, wound infection, intestinal obstruction, mesh infection, or chronic pain. Two patients (0.6%) developed re-recurrence requiring reoperation, with no further recurrence. CONCLUSION: When performed by an experienced surgeon with excellent technique, the TAPP technique is safe and effective for recurrent hernia after surgical treatment via the anterior repair, and maybe a good alternative for recurrent hernia after surgical treatment via the posterior repair.

Direct combustion of waste oil in domestic stove by an internal heat re-circulation atomization technology: Emission and performance analysis.

Direct use of waste oil as fuel to meet the residential energy demands, is very attractive due to its potentials to decrease fossil fuel consumption, reduce pollution and increase sustainability. This paper uses a domestic stove with an internal heat re-circulation and self-atomization technology to burn yellow waste cooking oil (WCO-1), brown waste cooking oil (WCO-2) and waste lubricant oil (WLO). Emission factors (EFs), energy efficiency and modified combustion efficiency (MCE) of this combined fuel/stove system were determined under space-heating and cooking modes. The results showed that EFs of CO, PM2.5, total 16 PAHs and corresponding toxic equivalent quantity (TEQ) values ranged from 2.18 × 103 to 4.90 × 103 mg/MJnet, 16.36-69.40 mg/MJnet, 2.39-12.93 µg/MJnet and 0.16-0.92 µg of TEQ/MJnet. WCO-1 was verified to be the cleanest fuel with the highest energy efficiency (85.3 ± 3.3% and 90.4 ± 2.2%) and lowest emission levels, such as NO (53.75 ± 2.62 and 37.09 ± 5.41 mg/MJnet), NO2 (82.40 ± 3.96 and 56.87 ± 8.29 mg/MJnet) and PM2.5 (20.94 ± 6.55 and 16.35 ± 5.06 mg/MJnet) compared to WCO-2 and WLO. The estimated total cost of using waste oil for each household in winter was much cheaper than some current available clean energy means, including only USD$ 400 of stove price and USD$ 250/ton of fuel per year. It is a promising candidate choice for replacing low-quality solid fuels in rural China and 2.62 million rural households would achieve environmental and economic benefits if promoting direct combustion of waste oil for daily heating and cooking.

Backflow Effect Enabling Fast Response and Low Driving Voltage of Electrophoretic E-ink Dispersion by Liquid Crystal Additives.

Electrophoretic display encountered several challenges towards high frame rate applications, such as long response time and high driving voltage. In this study, liquid crystal additive doping can simultaneously increase the response speed by 2.8 times and reduce the driving voltage to half of the initial value of electrophoretic dispersion. The backflow effect of liquid crystal, which induces an inversely electrorheological effect and facilitates the reverse micelles' dielectrophoretic separation, was suggested to be the main reason for the performance improvement. The proposed method is facile and effective which shows promising potential for fast response and low power consumption e-paper applications.

Negentropy Spectrum Decomposition and Its Application in Compound Fault Diagnosis of Rolling Bearing.

The rolling bearings often suffer from compound fault in practice. Compared with single fault, compound fault contains multiple fault features that are coupled together and make it difficult to detect and extract all fault features by traditional methods such as Hilbert envelope demodulation, wavelet transform and empirical node decomposition (EMD). In order to realize the compound fault diagnosis of rolling bearings and improve the diagnostic accuracy, we developed negentropy spectrum decomposition (NSD), which is based on fast empirical wavelet transform (FEWT) and spectral negentropy, with cyclic extraction as the extraction method. The infogram is constructed by FEWT combined with spectral negentropy to select the best band center and bandwidth for band-pass filtering. The filtered signal is used as a new measured signal, and the fast empirical wavelet transform combined with spectral negentropy is used to filter the new measured signal again. This operation is repeated to achieve cyclic extraction, until the signal no longer contains obvious fault features. After obtaining the envelope of all extracted components, compound fault diagnosis of rolling bearings can be realized. The analysis of the simulation signal and the experimental signal shows that the method can realize the compound fault diagnosis of rolling bearings, which verifies the feasibility and effectiveness of the method. The method proposed in this paper can detect and extract all the fault features of compound fault completely, and it is more reliable for the diagnosis of compound fault. Therefore, the method has practical significance in rolling bearing compound fault diagnosis.

Clinical effects of prosthetic mesh in the treatment of incarcerated groin hernias.

BACKGROUND: Incarcerated groin hernias are a common presentation as surgical emergencies. Other surgical treatment modalities are becoming more widely accepted including the use of prosthetic mesh and laparoscopy for assessment of hernia content viability and for repair. The aim of this study was to report our current experience with the use of prosthetic mesh in the treatment of incarcerated hernias and to compare the effects of different operative approaches. METHODS: This retrospective study included 219 consecutive patients who underwent herniorrhaphy for incarcerated hernia between January 2013 and December 2017 in Beijing Chao-Yang Hospital. Twenty patients who were not used mesh were excluded. Patients who died in the postoperative period due to systemic complications, as well as those who were lost during the follow-up period, were excluded from the study. Demographics, surgical details, short term and long-term outcomes were collected. Mann-Whitney U-test and χ2 test were used for statistical analysis. RESULTS: A total of 156 patients (78.4%) presented with inguinal hernias, 42 with femoral hernia (21.1%), and one with mixed hernia (0.5%), respectively. Mesh was placed in 199 patients (100%), including 15 patients with concomitant bowel resection. Four patients (2.0%) developed surgical site infections (SSI), four patients (2.0%) had foreign body sensation, one patient (0.5%) had hernia recurrence, two patients (1.0%) had chronic pain, 22 patients (11.1%) had seroma, and the mortality was 2.0%. No significant difference was noted concerning the development of surgical site infection, postoperative recurrence, chronic pain, foreign body sensation, and mortality rates between the transabdominal preperitoneal (TAPP) repair and open mesh repair. There was statistically significant difference in the postoperative incidence of seroma between two groups (12 of 49 [24.5%] vs. 10 of 150 [6.7%]; P=0.001). CONCLUSIONS: Our experience demonstrates that acutely incarcerated or strangulated groin hernia in adults is a serious neglected problem. The use of mesh could become current practice even in case of bowel resection. There was no statistically significant difference in the postoperative complications between TAPP repair and open mesh repairs except seroma.

Transabdominal preperitoneal laparoscopic approach for incarcerated inguinal hernia repair: A report of 73 cases.

To investigate the efficacy, key technical points, and complication management of the transabdominal preperitoneal (TAPP) approach for incarcerated inguinal hernia repair. Seventy-three patients with incarcerated inguinal hernias underwent TAPP surgery in our department between Jan 2010 and Dec 2015. A retrospective review was performed by analyzing the perioperative data from these patients. The operation was successfully completed in all 73 patients. Operation time was 54.0 ±â€Š18.8 minutes (range, 35-100 minutes). Length of stay was 3.9 ±â€Š1.1 days (range, 3-9 days). There was 1 case of incisional infection, 32 cases of seroma, and 3 cases of postoperative pain during follow-up. All patients recovered after the appropriate treatment. No recurrence or fistula was observed. The TAPP approach represents a safe and effective technique for incarcerated inguinal hernia repair because of its potential in assessment of hernia content and decreasing incisional infection rate. However, it requires experienced surgeons to ensure safety with special attention paid to the key technical points as well as complication management.

Preparation and helical folding of aromatic polyamides.

Long aromatic polyamide chains are prepared from the corresponding monomers. The resultant polymer adopts a hollow helical conformation that is stabilized by intramolecular H-bonding interaction between side chains.

Synthesis of cationic poly(4-vinylpyridine)-functionalized colloidal particles by emulsion polymerization with reactive block copolymer for protein adsorption.

We report here a novel protein sequestration method using polymeric colloidal particles prepared by emulsion polymerization with reactive block copolymers. Specifically, poly(4-vinyl-N-ethylpyridine bromide)-block-polymethylacrylate block copolymers were synthesized from reversible addition-fragmentation chain transfer polymerization and used as emulsifiers for emulsion polymerization of poly(4-vinyl-N-ethylpyridine bromide)-functionalized polymeric colloidal particles. The particles have high and stable zeta potentials when dispersed in solution, regardless of pH variations. As a result, the polymeric colloids demonstrate a high affinity for oppositely charged proteins, even though the isoelectric points of proteins may vary greatly. We show here that BSA can be sequestered highly efficiently with a maximum binding capacity (~900 mg/g). The adsorbed protein is easily released, and the polymeric colloids are regenerated after washing with a buffer solution of high ionic strength. These properties may prompt this type of novel macromolecule-functionalized colloids to be utilized for effective protein adsorption and separation.

Synthesis and property of chitosan graft copolymer by RAFT polymerization with tosylic acid-chitosan complex.

pH- and thermo-sensitive (1→4)-2-amino-2-deoxy-ß-d-glucan (i.e. chitosan) graft copolymer was prepared by reversible addition fragmentation chain transfer polymerizations of N-isopropylacrylamide with 4-methylbenzenesulfonic acid (i.e. tosylic acid)-chitosan complex. The polymerization was controlled well, and the amino group of chitosan could be deprotected easily and mildly with 15% Tris solution. The model aldehyde vanillin was conjugated with amino group of chitosan-g-PNIPAM via Schiff base bond (Loading efficiency, LE=77.6 mg/g), and the drug release could be controlled with temperature and pH. This property may promote the chitosan graft copolymer to be used in the field of "smart" drug delivery.