Highly efficient flexible perovskite solar cells with vacuum-assisted low-temperature annealed SnO2 electron transport layer

The demand for lightweight, flexible, and high-performance portable power sources urgently requires high-efficiency and stable flexible solar cells. In the case of perovskite solar cells(PSCs), most of the common electron transport layer(ETL) needs to be annealed for improving the optoelectronic properties,while conventional flexible substrates could barely stand the high temperature. Herein, a vacuumassisted annealing SnO_(2) ETL at low temperature(100℃) is utilized in flexible PSCs and achieved high efficiency of 20.14%. Meanwhile, the open-circuit voltage(V_(oc)) increases from 1.07 V to 1.14 V. The flexible PSCs also show robust bending stability with 86.8% of the initial efficiency is retained after 1000 bending cycles at a bending radius of 5 mm. X-ray photoelectron spectroscopy(XPS), atomic force microscopy(AFM), and contact angle measurements show that the density of oxygen vacancies, the surface roughness of the SnO_(2) layer, and film hydrophobicity are significantly increased, respectively. These improvements could be due to the oxygen-deficient environment in a vacuum chamber, and the rapid evaporation of solvents. The proposed vacuum-assisted low-temperature annealing method not only improves the efficiency of flexible PSCs but is also compatible and promising in the large-scale commercialization of flexible PSCs.

New Wireless Handheld Ultrasound-Guided Vacuum-Assisted Breast Biopsy (VABB) Devices: An Important Innovation in Breast Diagnosis

Vacuum-assisted breast biopsy (VABB) plays a fundamental role in the preoperative assessment of breast lesions pro- viding large histology samples that are useful to define diagnoses and biological parameters to guide treatment planning. This technique has been used in our institute since 2000 and two new wireless handheld ultrasound-guided VABB de- vices have been introduced since May 2012. In this report we analyze our experience with these revolutionary devices which are able to provide the option of single-insertion contiguous tissue samples respectively with a 13/14-gauge aperture. Our initial experience on 75 lesions shows that these devices are safe, fast, procedurally advantageous for operators and well accepted by patients. Finally VABB procedures can markedly reduce the need for surgical biopsy.

Diagnosis and excision of breast multi-focal lesions by ultrasound-guided vacuum-assisted biopsy:a comparative evaluation

Objective To compare and evaluate the efficacy of diagnosis and excision for appropriately selected breast multi-focal lesions and solitary lesion by ultrasound-guided vacuum-assisted biopsy(UGVAB).Methods Among 392 appropriately selected patients,187 patients with multi-focal lesions and 205 patients with solitary lesion were treated by the 8-gauge UGVAB from May 2007 to June 2009.All lesions were removed as completely as possible.The patients with benign pathology underwent physical and ultrasound examinations at one week and 6 months after procedure.Results During the procedure,only three patients had vasovagal syncope and twenty others complained of other intraoperative discomfort.An accurate pathological diagnosis was obtained in all lesions.There was no apparent false-negative result among the 696 lesions with benign pathology at a follow-up of 6 months after procedure.The rates of malignant or premalignant pathology,postoperative complications and residual lesions in patients with multi-focal lesions were higher than those in patients with solitary lesion.If each lesion was considered as a subject of study,there was no significant difference between the two groups.Conclusion UGVAB is an effective method for diagnosis and excision of appropriately selected breast multi-focal lesions and can be used routinely.

Efficacy and prognosis of vacuum-assisted excision for benign intraductal papilloma of breast:A meta-analysis

Objective:To evaluate the safety and effectiveness of vacuum-assisted excision for benign intraductal papilloma of breast.Methods:The databases including PubMed,Embase,Cochrane Library,WangFang,CNIK,VIP and Web of Science were searched by computer,according the inclusion and exclusion criteria after screening of literature.The Cochrane handbook and Newcastle-Ottawa scale was used to evaluate the studies.Then the Review Manager 5.3 software was to used analyze the data.Results:A total of 1016 patients was included in 9 articles.The amount of blood loss in vacuum-assisted surgery was less than that in open surgery[MD=-6.38,95%CI(-9.90,-2.86),P<0.05].The drainage[MD=-2.56,95%CI(-4.97,-0.15,P<0.05]and drainage time[MD=-0.25,95%CI(-0.40,-0.09),P<0.05]in vacuum-assisted surgery was less than that in open surgery.There were also few postoperative complications than that in open surgery[RR=0.43,95%CI(0.29,0.64),P<0.05].Compared with open surgery,the postoperative recurrence rate was lower in vacuum-assisted surgery[RR=0.26,95%CI(0.14,0.49),P<0.05].Last,there was no statistically significant difference in the operative time between vacuum-assisted surgery and open surgery,[SD=-12.82,95%CI(-25.70,0.06),P=0.05].Conclusion:Compared with open surgery,vacuum-assisted excision has the advantages of less blood loss and lower postoperative complications,but the operative time is not statistically significant compared with open surgery.In addition,compared with open surgery in this study,vacuum-assisted excision has the advantages of lower recurrence rate,but it still needs long-term dynamic observation.

Efficacy and Safety of Ultrasound Guided Vacuum-Assisted Excision of Fibroadenomas: A Systematic Review

Background: Ultrasound-guided, vacuum-assisted excision [UGVAE] of fibroadenomas is an emerging minimally invasive procedure. UGVAE is being increasingly employed by breast radiologists and surgeons. It has been approved for this use since 2006 by the National Institute for Health and Clinical Excellence in the UK. The aim of this systematic review is to evaluate the efficacy and safety of this procedure based on the up to date available evidence. Methods: A comprehensive literature search of the Cochrane library, Medline, Embase, PubMed, Google scholar, Trip-database, Internet, and the reference lists of relevant articles was performed. We searched for literature with sizeable cases of therapeutic vacuum-assisted excision of fibroadenomas. All prospective studies with more than 20 study participants were screened. The study quality was assessed using the Grading of Recommendations Assessment, Development, and Evaluation [GRADE] approach. All were in English. Results: Of the four case series that fulfilled the inclusion criteria there were 516 patients in which 520 procedures were performed. Overall complete excision rate was 89.4%. In two of the studies, this was 100% when the lesions were less than 1.5 cm but reduced to 61% when between 1.5 and 2 cm. Most common significant complication was bleeding with 2 cases of pneumothorax. None of the studies can be regarded as high quality going by GRADE approach. Conclusion: Within the limit of the current published case series, UGVAE appears to be an effective and safe procedure for excision of small fibroadenomas of less than 15 mm in size. A well designed case control study or randomized controlled trials with a sufficient sample size is needed to further assess its safety, effectiveness and more importantly, patients’ satisfaction especially in larger sized fibroadenomas.

Perfusionist strategies for blood conservation in pediatric cardiac surgery

There is increasing concern about the safety of homologous blood transfusion during cardiac surgery,and a restrictive transfusion practice is associated with improved outcome.Transfusion-free pediatric cardiac surgery is unrealistic for the vast majority of procedures in neonates or small infants;however,considerable progress has been made by using techniques that decrease the need for homologous blood products or even allow bloodless surgery in older infants and children.These techniques involve a decrease in prime volume by downsizing the bypass circuit with the help of vacuumassisted venous drainage,microplegia,autologous blood predonation with or without infusion of recombinant(erythropoietin),cell salvaging,ultrafiltration and retrograde autologous priming.The three major techniques which are simple,safe,efficient,and cost-effective are:a prime volume as small as possible,cardioplegia with negligible hydric balance and circuit residual blood salvaged without any alteration.Furthermore,these three techniques can be used for all the patients,including emergencies and small babies.In every pediatric surgical unit,a strategy to decrease or avoid blood bank transfusion must be implemented.A strategy to minimize transfusion requirement requires a combined effort involving the entire surgical team with pre-,peri-,and postoperative planning and management.

Directional Electromagnetic Interference Shielding Based on Step-Wise Asymmetric Conductive Networks

Some precision electronics such as signal transmitters need to not only emit effective signal but also be protected from the external electromagnetic(EM)waves.Thus,directional electromagnetic interference(EMI)shielding materials(i.e.,when the EM wave is incident from different sides of the sample,the EMI shielding effectiveness(SE)is rather different)are strongly required;unfortunately,no comprehensive literature report is available on this research field.Herein,Nicoated melamine foams(Ni@MF)were obtained by a facile electroless plating process,and multiwalled carbon nanotube(CNT)papers were prepared via a simple vacuum-assisted self-assembly approach.Then,step-wise asymmetric poly(butylene adipate-co-terephthalate)(PBAT)composites consisting of loose Ni@MF layer and compact CNT layer were successfully fabricated via a facile solution encapsulation approach.The step-wise asymmetric structures and electrical conductivity endow the Ni@MF/CNT/PBAT composites with unprecedented directional EMI shielding performances.When the EM wave is incident from Ni@MF layer or CNT layer,Ni@MF-5/CNT-75/PBAT exhibits the total EMI SE(SET)of 38.3 and 29.5 dB,respectively,which illustrates theΔSET of 8.8 dB.This work opens a new research window for directional EMI shielding composites with step-wise asymmetric structures,which has promising applications in portable electronics and next-generation communication technologies.

Preoperational diagnosis and management of breast ductal carcinoma in situ arising within fibroadenoma:Two case reports

BACKGROUND Ductal carcinoma in situ(DCIS)arising within fibroadenoma is a type of tumor that is rarely encountered in clinic,with only about 100 cases of carcinoma arising within a fibroadenoma reported in the literature.Here,we present two cases of breast DCIS arising within a fibroadenoma and discuss their clinical and imaging findings as well as treatment.CASE SUMMARY The patients did not have cancer-related personal and family histories.Case 1(a 49-year-old woman)was diagnosed with a bilateral breast nodule in May 2018 and was followed(preoperative imaging data including ultrasound and mammography)for 3 years;she underwent an excisional biopsy to address an enlargement in nodule size.Case 2(a 37-year-old woman)was diagnosed with a left breast nodule in June 2021 and consequently received vacuum-assisted biopsy of the tumor which appeared as“irregularly shaped”and“unevenly textured”tissue on ultrasound.The pathological diagnosis was clear in both cases.Both patients underwent breast-conserving surgery and sentinel lymph node biopsy.The two cases received or planned to receive radiotherapy as well as endocrine therapy(tamoxifen).CONCLUSION Breast DCIS arising within a fibroadenoma is rare,but patients treated with radiotherapy and endocrine therapy can have good prognosis.

Negative Pressure Wound Therapy—An Effective, Minimally Invasive Therapeutic Modality in Burn Wound Management

Despite the advancement in burn therapy in the last decades the treatment of burn wounds still remains a challenging task. Infection is still a common complication;while sepsis remains the leading cause of death in severe burns. The research guided integration of new and effective techniques in burn wound management is mandatory. Negative pressure wound therapy (NPWT) is an effective and widely used technique in the management of problematic wounds. Previously existing indications include soft tissue traumas and chronic wounds such as diabetic, arterial, venous and pressure ulcers. The characteristics and challenges of these wounds have a lot in common with burns. Since the early 2000’s there are experiences with the use of NPWT for the healing of second degree burn wounds. Our clinical experience shows that it is a minimally invasive and effective way of improving burn wound management. In this article we give a review of the literature showing the mechanisms, unmapped future opportunities, financial issues, and possible adverse effects of NPWT in burn therapy.

Deep Sternal Wound Infections after Coronary Artery Bypass Grafting: Analysis of 29 Cases from Iraq

Background: Deep sternal wound infection (DSWI), or mediastinitis, is a devastating complication of coronary artery bypass grafting (CABG). This prospective study aimed to assess our management of DSWI in view of the published literature. Methods: Over 2-years (ending in January 2016), 29 patients (20 males) developed DSWI amongst 520 patients who underwent standard CABG surgeries (5.6%). Pre-, intra- and postoperative variables were documented. Whenever possible, the infections were culture-verified. Besides antibiotics, patients received one or more of the following therapies: drainage, debridement, closed irrigation, sternal re-wiring, vacuum-assisted closure (VAC), and bone resection. Results: the male to female ratio was 2.2:1. Mean age was 58.1 ± 7.3 years. The mean body mass index (BMI) was 27.9 ± 3.4 kg/m2. There were 18, 16 and 11 patients with diabetes mellitus (DM), hypertension and chronic obstructive pulmonary disease (COPD) respectively. Cardiopulmonary bypass (CPB) was utilized in 26 (89.7%) patients with a mean time of 117.5 ± 23.3 minutes. Most surgeries (n = 21, 72.4%) lasted 5 - 6 hrs. According to Pairolero classification, there were 3 (10.3%) Type I, 22 (75.9%) Type II and 4 (13.8%) Type III infections. Four (13.8%) cases were culture-verified. Twenty-three (79.3%) DSWIs were surgically managed. Sternal re-wiring was performed in 14 (48.3%) cases while VAC was added to other therapies in 2 (6.9%) patients. DSWIs completely resolved in 18 (62.0%) patients within 3 - 24 weeks while two (6.9%) patients died within 30 days. Conclusion: We have identified six independent risk factors for DSWI (male gender, obesity, DM, hypertension, COPD and CPB), five of them are modifiable.

Characterization of the Grain Structures in Vacuum-Assist HighPressure Die Casting AM60B Alloy

The structures in vacuum-assist high-pressure die casting （HPDC） AM60B alloy were studied by using an optical microscope and a scanning electron microscope with an energy dispersive spectrometer. It was found that the HPDC under the vacuum could significantly change the morphology and distribution of the microstructure. For both conventional and vacuum-assist HPDC processes, the externally solidified crystals （ESCs） tended to aggregate in the center along the thickness direction of the castings. Besides, the aggregation was more pronounced, and the number of ESCs decreased, and the ESCs tended to become smaller and more globular, as the distance between the specimen location and runner increased. Compared with the conventional castings, the vacuum-assist HPDC can significantly reduce the size and amount of ESCs, and the ESCs tended to be more globular. For the distribution of ESCs along the thickness of the specimens, the aggregation tendency was more pronounced in vacuum-assist die castings than that in conventional castings. Besides, the distribution of ESCs at different locations was more converged in the vacuum-assist HPDC than that in the conventional HPDC.

Consensus on the application of negative pressure wound therapy of diabetic foot wounds

Because China is becoming an aging society,the incidence of diabetes and diabetic foot have been increasing.Diabetic foot has become one of the main health-related killers due to its high disability and mortality rates.Negative pressure wound therapy(NPWT)is one of the most effective techniques for the treatment of diabetic foot wounds and great progress,both in terms of research and its clinical application,has been made in the last 20 years of its development.However,due to the complex pathogenesis and management of diabetic foot,irregular application of NPWT often leads to complications,such as infection,bleeding and necrosis,that seriously affect its treatment outcomes.In 2020,under the leadership of Burns,Trauma and Tissue Repair Committee of the Cross-Straits Medicine Exchange Association,the writing group for‘Consensus on the application of negative pressure wound therapy of diabetic foot wounds’was established with the participation of scholars from the specialized areas of burns,endocrinology,vascular surgery,orthopedics and wound repair.Drawing on evidence-based practice suggested by the latest clinical research,this consensus proposes the best clinical practice guidelines for the application and prognostic evaluation of NPWT for diabetic foot.The consensus aims to support the formation of standardized treatment schemes that clinicians can refer to when treating cases of diabetic foot.

Flow correction control with electromagnetically induced preform resting process

Resin flow correction control with electromagnetic field source, a new variation of the vacuum-assisted resin transfer molding (VARTM) process called electromagnetically induced preform resting (EIPR) for dynamical resin flow controlling is introduced to manipulate the flow front and local permeability to prevent the formation of dry spots. This paper proposes an active and real-time flow control approach that is implemented during the composite laminate infusion. The EIPR process applies an electromagnetic field source to pinch (raise) and vibrate the upper flexible mold to rest the fiber preform and increase the local permeability. Vibration action delivers the fluid through the preform. The EIPR process includes a new and creative upper flexible vacuum bag with embedded elements to lift and create local vibrations via an automated gantry system. The control methodology is performed by tracking the flow front with a real-time correction. System capability is demonstrated with three configurations of preform of different preform permeabilities in each experiment. A low permeability preform is employed in these configurations to disturb the flow pattern and cause an artificial problem or pseudo problem during the filling process. The results indicate that this system fills the mold completely and reduces the filling time without any dry spots and therefore creates no waste material.