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A 63-year-old woman presented with acute left foot ischaemia with pain, sensory loss and moderate motor deficit. She was a heavy smoker with arterial hypertension, hyperlipidaemia and a history of left breast cancer 15 years ago. She urgently underwent a standard Fogarty embolectomy through a left

Purpose: Anastomotic leakage, a known major postoperative complication, potentially leads to readmission, reoperation, and increased mortality rates in patients, such as rectal cancer patients following a low anterior resection (LAR). Currently, vacuum-assisted closure, as featured by B-Braun (B-Braun Medical B.V.), is already being used for the treatment of gastrointestinal leakages and fistulas. The main aim of this study was to introduce a novel method for creating a vacuum-assisted drain for the treatment of anastomotic leakage after LAR.Methods: All 10 patients, who underwent LAR surgery from 2018 to 2019, were diagnosed with anastomotic leakage and had received neoadjuvant chemotherapy prior to surgery. Therefore, patients were treated with a handmade vacuum-assisted drain and were revisited every 5 to 7 days for further evaluations and drain replacement until leakage resolution. Physical features of cavity, time of diagnose, and duration of treatment were analyzed correspondingly. The handmade vacuum-assisted sponge drain was prepared for each patient in each session of follow-up.Results: Eight out of 10 patients experienced complete closure of the defect. The mean delay time from the day of operation to the diagnosis of anastomotic leakage was 61.0±80.4 days while the mean time for leakage closure was 117.6±68.3 days. Eventually, 7 cases underwent ileostomy reversal with no complications during a 3-month follow-up.Conclusion: In this study, we evaluated the healing process of anastomotic leakage after the usage of a handmade vacuum-assisted sponge drain in a case series method. In our trial, we provided an innovative cost-benefit method easily applicable in the operating room.

In the present study microwave (MW), ultraviolet (UV), and vacuum (VC) were applied individually as well as in combination as a non-chemical treatment method to investigate its efficiency in controlling adult stage of R. dominica in rice grains at 14, 16 and 18 % moisture content (MC); 180, 360, 540, 720, and 900W power levels, and for 10- 60 s holding time. The UV and VC levels were kept constant at 365 nm and 382 mm of Hg. Thus, the mortality of R. dominica, using MW, MW+UV, and MW+UV+VC at varying power levels, exposure times, and MC was evaluated along with the changes in the quality characteristics of the treated rice in comparison to the control rice. The mortality (%) of the R. dominica was 90-92 % for MW treatment, 90-100 % for both MW+UV, and MW+UV+VC treatments respectively. The temperature reached was 41℃ to 81℃ for the MW, 42 ℃ to 92 ℃ for the MW+ UV, 33 ℃ to 94 ℃ for the MW+UV+VC treatment at 180-900W respectively. The MC played a significant role in achieving a higher mortality rate of R. dominica in all the treatments (MW, MW+UV, and MW+UV+VC). The results also signified that the combinational approach of MW+UV+VC treatment works much better than the other two approaches (MW and MW+UV treatment) in terms of R. dominica mortality rate (%). Also, MW+UV+VC treatment leads to minimal changes in the quality attributes of the grain due to the additional presence of vacuum during the entire treatment process.

Flail chest is associated with high rates of morbidity and mortality and management of such condition is a multidisciplinary task that should be based on pain control, judicious fluid administration, adequate pulmonary hygiene and management of the paradoxical movements of the thoracic wall. Many methods of treating rib fractures and flail chest have been developed over the years. Our aim was to evaluate a novel method of flail chest stabilization using negative vacuum pressure and compare it to a traditional method. Material and methods: 10 patients with flail chest from trauma admitted in Thoracic Surgery Clinic from Clinical County Emergency Hospital of Craiova and County Emergency Hospital of Targoviste were submitted to stabilization using Vacuum Assisted Closure kit. This series of patients were compared with 10 patients in whom a traditional method of stabilization was used, selected from the database of patients from the Thoracic Surgery Clinic of Clinical Emergency Hospital of Craiova, used as control group. Results: The 2 groups were comparable as no statistically significant differences were found regarding the gender, mean age, type of trauma, associated trauma, preexistent conditions, number of rib fractures, presence of pulmonary contusion, thoracic deformity. The parameters investigated: number of days with mechanical ventilation, number of days spent in ICU, total hospital stay, mortality didn’t reach statistically significant differences. The only significant results found were for the pain scores recorded at 2 weeks and 1 month after discharge, the VAC stabilization being significantly better than traditional method. Conclusions: A larger study is required to establish if the advantages of the VAC assisted stabilization of the flail chest are superior to traditional treatment.

This study aimed to compare the effects of hot water and vacuum blanching methods on physico-chemical parameter, total phenols (TPC) and flavonoids content (TFC), and antioxidant activity of zucchini slices during 28 days storage. A significant decrease in Chroma parameter was observed over time, on the other hand, no significant differences were observed between the Hue angle ​​either between samples treated with the two blanching methods or during storage. A minimal reduction in the TPC was observed in all samples, independently by the applied treatment, compared to the value of untreated product whereas a more marked reduction in TFC compared to untreated zucchini slices was observed (− 39.91% and − 32.02% for vacuum blanched (ZS8) and hot water blanched (ZB8) zucchini treated for 8 min, respectively, respect the untreated zucchini samples at D0). First-order kinetic model was applied to monitor the effect of the two blanching processes on zucchini slices. The application of vacuum blanching allows for greater retention of bioactive compounds over time with a half-life time (t1/2) of 161 and 47 days for ZS8 versus 87 and 23 days for ZB8, respectively. Samples treated with both blanching procedure for 8 min exhibited a more markedly ABTS radical activity respect untreated one (IC50 values of 17.55 and 14.98 μg/mL for ZS8 and ZB8, respectively vs 20.45 μg/mL for untreated zucchini). In general, the results obtained allow to identify in the vacuum treatment a method applicable to zucchini slices to maintain their qualitative characteristics over time.

Application of negative-pressure wound therapy dressings to the web spaces and small, often moist, areas of the hand can be technically demanding and time consuming. The researchers present a case report and technique for managing a devastating hand infection and soft-tissue defects by creating a self-fabricated sponge-glove that is easily reproducible. Vacuum-assisted therapy for combined volar dorsal soft-tissue defects of the hand, or "Hand Vac," is a novel approach for treating extensive hand wounds. This technique was used in a patient with diabetes with a deep space infection of the hand following serial debridements and antibiotic bead therapy. A single, medium size sponge was cut using a knife and scissors to create an easily applied glove that was then sealed with adhesive dressing and a single suction port. The patient avoided complete amputation of the hand and deep infection was eradicated. The wounds had progressive granulation and healing and were eventually covered with split-thickness skin grafts. The authors conclude that severe soft-tissue defects involving both the volar and dorsal aspects of the hand can be effectively managed with a single glove-like sponge and suction port.

To evaluate neonatal and maternal outcomes associated with detachment of non-metal vacuum cup during delivery and to identify risk factors for these detachments. This retrospective cohort study included women with singleton pregnancy, who underwent vacuum-assisted vaginal delivery with a non-metal vacuum cup in a single academic institution, January 2014–August 2019. Failed vacuum deliveries were excluded. Primary outcomes were defined as subgaleal hematoma (SGH) and cord blood pH 3700 g (14.1% vs, 10.3%, p = 0.006). Interestingly, there were more males in that group (60.6 vs. 54.6, p = 0.005). All these factors remained significant after controlling for potential confounders. Vacuum cup detachment has several predictive characteristics and is associated with adverse neonatal outcomes that should be incorporated into decisions made during the procedure.

Purpose Vacuum-assisted deliveries (VAD) are complex procedures that require training and experience to be performed proficiently. We aimed to evaluate if a more resource intensive practice-based training program for conducting VAD is more efficient compared to a purely theory-based training program, with respect to immediate training effects and persistence of skills 4–8 weeks after the initial training. Methods In this randomized-controlled study conducted in maternity staff, participants performed a simulated low-cavity non-rotational vacuum delivery before (baseline test) and immediately after the training (first post-training test) as well as 4–8 weeks thereafter (second post-training test). The study’s primary endpoint was to compare training effectiveness between the two study groups using a validated objective structured assessment of technical skills (OSATS) rating scale. Results Sixty-two participants were randomized to either the theory-based group (n = 31) or the practice-based group (n = 31). Total global and specific OSATS scores, as well as distance of cup application to the flexion point improved significantly from baseline test to the first post-training test in both groups (pall Conclusion A practice-based training program for conducting VAD results in comparable immediate improvement of skills compared to a theory-based training program, but the retention of skills 4–8 weeks after training is superior in a practice-based program. Future studies need to evaluate, whether VAD simulation training improves maternal and neonatal outcome after VAD.

We aimed to evaluate the effect of epidural analgesia (EA) on maternal and neonatal outcomes.We conducted a retrospective cohort database study on primiparous women who underwent a vacuum-assisted delivery (VAD) trial between 2005 and 2019 at a university-affiliated tertiary medical center. We compared women with and without the standard "one protocol" patient-controlled EA. The primary outcome was VAD failure. Secondary outcomes were maternal and neonatal morbidities. We performed univariate analysis, followed by multivariable logistic regression analysis to control for potential confounders. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated.Overall, 7042 primiparous women attempted VAD during the study period; 6238 (88.3%) and 804 (11.7%) women used and did not use EA, respectively. The VAD failure rate was significantly lower among women with than without EA use (2.5%EA use in primiparous women is associated with lower rates of VAD failure without an increase in adverse maternal or neonatal outcomes.

The interfacial issue is a critical factor affecting the thermoelectric performance in the organic–inorganic composite system. However, in the traditionally adopted solution casting method for orga...

Vacuum-assisted abdominal closure (VAAC) has evolved as a promising method for treatment of emergent surgical patients. The aim of the study was an assessment of the complication rate and outcomes following routine application of VAAC in a cohort of patients suffering predominantly with peritonitis of the lower gastrointestinal tract (GIT) origin. The prospectively collected data was analysed retrospectively, including demographic data, aetiological factors, comorbid conditions and severity of the disease. The indications for VAAC included complicated intra-abdominal infection, purulent peritonitis with sepsis and/or risk of increased intra-abdominal pressure. In total, 130 patients were managed with VAAC. The median age was 63.5 years, with a predominance of male patients (61.5%). Systemic inflammatory response was present in 68.5%, the median C-reactive protein (CRP) was 239.58 mg/l, Procalcitonin (PCT) level 7.02 ng/ml, and lactate 1.84 mmol/l before intervention. The median Sequential Organ Failure Assessment (SOFA) score was 4 and the Mannheim Peritonitis Index was 26. Sepsis developed in 87.0% of patients, and 43.8% had septic shock. VAAC was applied in 58.5% due to a perforation of the lower GIT, in 26.1% due to perforation of the upper GIT, and in 15.4% for other reasons. A median of two (interquartile range, IQR 1–3) VAAC system changes were performed in a period of 7 (IQR 4–11) days. In 88.6% of cases, multiple types of microorganisms were present. The application of VAAC resulted in a significant decrease of the postoperative SOFA score, and CRP, PCT and lactate levels (p < 0.001). The complications included a “frozen abdomen”, enterocutaneous fistula, intraabdominal abscess and bleeding in 7.7%, 5.4% and 6.0% cases, respectively. Primary abdominal closure was accomplished in 76.2%, resulting in a 23.1% mortality rate. VAAC was found to be safe in the treatment of abdominal sepsis including in patients with faecal peritonitis. Complete abdominal closure can be achieved in the majority of patients resulting in a lower mortality rate.

In this work, we report the effect of seed particle size towards the formation of NaX zeolite membranes through single and multi-stage hydrothermal growth methods. A seed layer was firstly deposited onto the α-alumina support via vacuum-assisted seeding technique prior to hydrothermal growth of the membrane layer. The morphology and crystallinity of the membranes were characterized by using scanning electron microscope (SEM) and X-ray diffraction (XRD), respectively. From the results obtained, by using smaller seed particles of 750 nm, the growth of the membrane layer was enhanced due to minimum gaps found in between the seed particles. The N2 gas permeation results showed that the multistage synthesis method has successfully reduced the defects of the membranes. However, it was observed that the presence of zeolite NaP impurities in the membrane layer became more significant along with the increase of the synthesis stage.

Prefabricated horizontal drain (PHD) assisted by vacuum pressure has been used in practice to accelerate the consolidation process of dredged soft mud. However, very few studies have investigated t...

This paper aims to evaluate the impact of simultaneous tri-frequency ultrasound (20 + 40 + 60 kHz) combined vacuum (0.6 bar) assisted ethanol (75%) pretreatment on the infrared drying process, qual...

Sludge drying is one of the main problems of wastewater treatment plants. It is very important to facilitate the drying process in terms of drying efficiency, time duration, and cost of the processes, so that transportation and dumping of sludge will accordingly be realized effectively. In this study, vacuum assisted thermal drying was studied. Under vacuum conditions, the water content of the sludge was examined easier than at atmospheric pressure in the drying process. For this reason, in this study, time, temperature, and sludge mass surface area on drying efficiency were evaluated under two different pressure levels, such as 30 mbar and 1,000 mbar. To optimize these parameters, the Response Surface Methodology approach was utilized. Results showed that the effect of vacuum condition on sludge drying was remarkable at obtaining at least 65% of solid material ratio in sludge, which is the lowest limit value on landfilling legislation in Turkey. Data obtained from the study shows that, especially at high temperatures, contribution on sludge drying of vacuum condition is more effective in terms of drying time. A smaller sludge surface area is also found more significant on vacuum drying.

Retained soft tissue foreign bodies following injuries are frequently seen in the Emergency and Plastic Surgery practice. The patients with such presentations require a watchful and detailed clinical assessment to overcome the anticipant possibility of missing them. However, the diagnosis based on the clinical evaluation is usually challenging and needs to be supported by imaging modalities that are suboptimal and may fail in identifying some types of foreign bodies. Owing to that, serious complications such as chronic pain, infection, and delayed wound healing can be faced that necessitate a prompt intervention to halt those detrimental consequences. The classical method of removal is a surgical exploration which is not free of risks. It can cause injuries to vital structures such as nerves and tendons if the foreign body is close to them, also it can be affected by the surgeon's experience and the foreign body's characteristics. In light of that, we conducted a single-center study to understand the utility of a novel vacuum-assisted technique for foreign body removal. The technique is noninvasive and facilitates a real-time foreign body extraction using readily available materials. Twenty patients with 23 Foreign Bodies of various kinds, shapes, and sizes were recruited in our study by using a nonprobability convenient sampling method. Results demonstrated the ability of the described technique to extract 22 of them with no noticeable side effects. This study may encourage further trials adopting similar principles to promote the management of retained foreign bodies with fewer complications, and a potential of time and cost-saving.

Objectives To determine the association between the number of pulls during vacuum-assisted deliver and neonatal and maternal complications. Methods This was a single-center observational study using a cohort of pregnancies who underwent vacuum-assisted delivery from 2013 to 2020. We excluded pregnancies transitioning to cesarean section after a failed attempt at vacuum-assisted delivery. The number of pulls to deliver the neonate was categorized into 1, 2, 3, and ≥4 pulls. We used logistic regression models to investigate the association between the number of pulls and neonatal intensive care unit (NICU) admission and maternal composite outcome (severe perineal laceration, cervical laceration, transfusion, and postpartum hemorrhage ≥500 mL). Results We extracted 480 vacuum-assisted deliveries among 7,321 vaginal deliveries. The proportion of pregnancies receiving 1, 2, 3, or ≥4 pulls were 51.9, 28.3, 10.8, and 9.0%, respectively. The crude prevalence of NICU admission with 1, 2, 3, and ≥4 pulls were 10.8, 16.2, 15.4, and 27.9%, respectively. The prevalence of NICU admission, amount of postpartum hemorrhage, and postpartum hemorrhage ≥500 mL were significantly different between the four groups. Multivariable logistic regression analysis found the prevalence of NICU admission in the ≥4 pulls group was significantly higher compared with the 1 pull group (adjusted odds ratio, 3.3; 95% confidence interval, 1.4–7.8). In contrast, maternal complications were not significantly associated with the number of pulls. Conclusions Vacuum-assisted delivery with four or more pulls was significantly associated with an increased risk of NICU admission. However, the number of pulls was not associated with maternal complications.

Background Low and mid station vacuum assisted deliveries (VAD) are delicate manual procedures that entail a high degree of subjectivity from the operator and are associated with adverse neonatal outcome. Little has been done to improve the procedure, including the technical development, traction force and the possibility of objective documentation. We aimed to explore if a digital handle with instant haptic feedback on traction force would reduce the neonatal risk during low or mid station VAD. Methods A two centre, randomised superiority trial at Karolinska University Hospital, Sweden, 2016–2018. Cases were randomised bedside to either a conventional or a digital handle attached to a Bird metal cup (50 mm, 80 kPa). The digital handle measured applied force including an instant notification by vibration when high levels of traction force were predicted according to a predefined algorithm. Primary outcome was a composite of hypoxic ischaemic encephalopathy, intracranial haemorrhage, seizures, death and/or subgaleal hematoma. Three hundred eighty low and mid VAD in each group were estimated to decrease primary outcome from six to 2 %. Results After 2 years, an interim analyse was undertaken. Meeting the inclusion criteria, 567 vacuum extractions were randomized to the use of a digital handle (n = 296) or a conventional handle (n = 271). Primary outcome did not differ between the two groups: (2.7% digital handle vs 2.6% conventional handle). The incidence of primary outcome differed significantly between the two delivery wards (4% vs 0.9%, p Conclusions The incidence of primary outcome was lower than estimated and the study was underpowered. However, the difference between the two delivery wards might reflect varying degree of experience of the technical equipment. An objective documentation of the extraction procedure is an attractive alternative in respect to safety and clinical training. To demonstrate improved safety, a multicentre study is required to reach an adequate cohort. This was beyond the scope of the study. Trial registration ClinicalTrials.gov NCT03071783, March 1, 2017, retrospectively registered.

A non-isothermal vacuum assisted hot-forming process using tailored laminate temperature is introduced. By using process simulation and manufacturing experiments, improved laminate quality is achieved compared to the standard hot-forming process. Furthermore, it is also shown that the manufacturing time in the clean room can be reduced to one tenth of the standard process time. In this study 8.4 mm thick quasi-isotropic laminates from unidirectional prepreg were laid up flat with an automatic tape laying machine and hot-formed to a U-shaped laminate. The laminates were then cured in a concave mould with standard bag on the inside. A complete tailored temperature hot-forming cycle of 7.5 min produced a very good final laminate quality with a total thickness variation as low as 4.0% and without wrinkles or indications of porosity. With a 4 min hot-forming cycle the thickness variation was also acceptable at 8%.

Carbon nanotube (CNT) reinforced 6063 aluminum (Al) matrix composites were fabricated by vacuum-assisted infiltration of molten 6063 Al alloy into a CNT preform to enhance compressive mechanical properties. Preforms were produced with different amounts of chemically functionalized CNTs to obtain three different CNT reinforcement ratios (0.25, 0.50, and 0.75 wt.%). In addition to the investigation of properties throughout all stages of the preparation of the CNTs, CNT preforms and fabricated composites by various methods of analysis, all steps of the composite fabrication process, as well as the compressive mechanical test results of CNT/6063 Al composites are all discussed. Approximately 250% and 280% increases in the yield and ultimate compressive strength, respectively, are achieved with low-purity CNT addition. Consequently, it is confirmed from the micrographs that the mechanical enhancements of the composites are mainly interrelated with the successful bridging of CNTs in the matrix material. Meanwhile, it is observed that both the modified Halpin-Tsai model and the modified Halpin-Tsai model developed with a dispersion-based prediction model results match with experimental results. Overall results can be accepted as developmental stages of significant progress in the CNT preform reinforced metal matrix composites field.

In a surgical ward, acute and continual wounds have an effect on a minimal of 1% of the population. Vacuum-assisted wound closure (VAC) is a technique of Negative pressure in the wound to improve the healing process. To study the advantage of a vacuum assisted closure over conventional dressing in the management of chronic non-healing diabetic ulcers. To study the difference in the rate of amputation, hospital stays in case and control groups. Group1-case group – vacuum associated closure therapy. Group 2-Control group -conventional dressings. Most of the patients in the study population was in the age group of 41 -60 years. 82% of the study population was within the age group of 41-60 years. The two groups are comparable with their baseline characteristic of age, and the P-value is less than 0.05. Wounds were more common in males than females. Out of the 44 patients, 26 were male, i.e. 57% of the study population were males. About 68% of wounds occurred in the foot. About 50% of the culture showed staphylococcus. Nearly 27% of study participants had no growth. The hospital stay is less in VAC dressing when compared to the conventional dressings, who have an average hospital stay of 28 days and the relation is statistically significant (p-value

Introduction: Vacuum assisted venous drainage (VAVD) requires the sealing of the hard-shell venous reservoir, thereby creating circumstances where reservoir pressurization may occur. Manufacturers utilize integrated pressure relief valves (IPRV) to mitigate pressurization risk; however, accidents have been reported even with these devices. We have undertaken a performance evaluation of IPRV’s in a large number of hard-shell venous reservoirs. Methods: Reservoirs were sealed and gas insufflated while measuring reservoir internal pressure. Linear regression models were developed to depict the association between internal pressure and gas inflow rate. External secondary one-way valves (ESOV) were assessed for pressure mitigation performance. An assisted venous drainage survey was circulated to Canadian Clinical Perfusionists. Results: The reservoirs tested were adult ( n = 9, 64%) and pediatric ( n = 5, 36%) designs. Significant variability ( p Conclusions: Significant variability among reservoir’s IPRV to mitigate reservoir pressurization exists. The predictive models are extremely accurate at estimating the internal pressure. ESOV performance limitations moderate their utility as a backup pressure mitigation technique. A significant number of reservoir pressurization events are occurring with the use of VAVD. As a result, standardized communication from manufacturers on the purpose and performance of IPRV is recommended in order to delineate the limitations of these devices.

Corn husk is a non-fruit part of the corn and an agricultural waste. This research focuses on fabricating composite material from the corn husk fibre by using a vacuum assisted resin infusion (VARI) technique. The corn husk fibre was extracted using water retting method and treated with alkali and bleaching treatments using sodium hydroxide (NaOH) and hydrogen peroxide (H2O2). Then, those fibres were made into nonwoven fibre mat using water laid method. The fibre mat was infused with epoxy resin to make a composite. The mechanical result has shown that the composite with 20% of fibre has higher tensile strength and modulus compared to neat epoxy. Both treatments have removed the non-cellulose content, such as hemicellulose and lignin. Moreover, the treatments also promoted better interfacial adhesion between fibre and matrix. Thus, the NaOH treated and H2O2 treated composites showed approximately 56% and 82%, respectively, higher tensile strength than untreated composite. Both treated composites were also stiffer and exhibited lower water absorption compared to untreated composite.

Cu(In,Ga)Se2 (CIGS) absorbers are prepared by direct current electrodeposition process followed by selenization of precursors. Selenization of electrodeposited layers is performed in a tubular furnace at 550 °C in elemental selenium atmosphere using Ar as carrier gas. The effect of evacuation of tube prior to the selenization on the formation of CIGS absorbers is studied. Characterization of CIGS absorbers reveals that the samples selenized without prior evacuation found to have excess MoSe2 formation at the CIGS/Mo interface leading to bulk cracks in underlying Mo back contact compared to their counterparts. Although the fabricated solar cells using the absorbers, prepared with and without evacuation, are observed to be photoactive, the cells from vacuum-based selenization showed improvement in performance compared to the cells from non-vacuum selenization. The process is further being improved to enhance the efficiency, which can pave way towards environmentally friendly low-cost solar cells.

This study evaluated whether episiotomy during vacuum-assisted delivery leads to fewer third- and fourth-degree tears. This was a retrospective cohort study of all nulliparas who underwent a singleton, soft cup, vacuum-assisted vaginal delivery in one institution, from January 2014 to August 2019. Failed vacuum deliveries were excluded. Based on power analysis calculation, a sample size of 500 women in each group was sufficient to detect an advantage of episiotomy, if present. Primary outcome was third- or fourth-degree perineal tear. Secondary outcomes were other maternal complications, and low neonatal cord pH and Apgar scores. Outcomes were compared between women with and without episiotomy. During the study period, 2370 nulliparas had a vacuum-assisted vaginal delivery using soft vacuum cup and met the study inclusion criteria. Episiotomy was performed in 1868 (79%) women, and 502 (21%) delivered without episiotomy. Background characteristics were similar in both groups. There were no significant differences in the rates of third and fourth grade perineal lacerations between the two groups. Episiotomy was associated with higher rate of postpartum hemorrhage (p

Woven fabric reinforced epoxy composite shown inherent favorable characteristics for aerospace industry applications. This paper comprehensively investigated the mechanical and fracture behavior of unidirectional carbon woven fabric reinforced epoxy composite using experimental and computational techniques. The composites were fabricated with two, four, and six ply laminates with cross-ply and inclined ply (45/–45) orientations. Laminates were fabricated using Vacuum-Assisted Resin Infusion Microwave Curing technique with a high fiber volume fraction of 50% for each laminate. Experimental analyses were performed to predict the behavior of composites under tensile, shear, and impact loading environment. Further, the mean-field homogenization technique coupled with the finite element method was employed to predict orthotropic material properties, fracture energy, and fracture parameters ( KIC and GIC) of the composite. The results showed that fracture energy obtained by the computational technique was in good agreement with experimental results. The values of GIC increased with the number of plies both for cross and inclined plies orientation composites. KIC values were higher for cross plies laminates than the inclined plies laminates.

Biolaminates of Ixtle and Henequen natural fibers reinforced bio-based epoxy resin were prepared using Vacuum Assisted Resin Infusion process. ZnO nanoparticles were added to the bio-based epoxy resin at 1, 2 and 3 wt. % content before impregnation process. The viscoelastic and mechanical properties, as well as the fracture behavior, were evaluated and related to the nature of the fibers and filler content. The viscoelastic results indicated the ZnO particles are effective fillers just at low concentrations, and induce different reinforcement mechanisms attributed to the interaction between the nature of fibers and nanoparticles. The mechanical properties of the Ixtle biolaminates decreased at higher filler concentrations, while Henequen biolaminates showed better mechanical properties just above the 2 wt. % of ZnO. The fracture behavior in mode I registered moderate changes in toughness, related to the ZnO fraction, which promoted different behaviors on the interlaminar adherence of the layers. The results point to the need to continue evaluating the potential application of these green composites for their use in construction and automotive industries.

A calculation model has been developed for large-strain radial consolidation incorporating lateral deformation in order to solve the problem of poor consolidation prediction for dredged sludge at high water content in vacuum preloading process. The differential solution for the proposed model is given, considering the effect of initial water content on the compression behavior. The model is suitable for unconsolidated soil and normally consolidated soil, which can take into account such factors as lateral deformation, varying compressibility and permeability coefficients, smearing effect, self-weight stress, negative pressure attenuation along the depth, etc. The proposed model is verified by comparing it with other existing theoretical solutions. Poisson’s ratio (v) is used to reflect the influence of lateral deformation on soil consolidation. The results show that lateral deformation has an important influence on soil consolidation degree, especially on consolidation degree defined by stress (Up). The consolidation rate increases with the increase of v. The traditional equal-strain solution overestimates the consolidation rate of foundation. At the same normalized elevation, the void ratio increases while the excess pore water pressure decreases with the increase of v.

Active drains, which work by negative pressure, are commonly used to drain closed airtight wounds. Higher negative pressure is used in vacuum-assisted wound closure dressings. Gastrointestinal leaks may be difficult to treat by surgical approach because of their association with high morbidity and mortality. Recently, endoscopic approaches have been applied with several degrees of success. Most recently, endoluminal vacuum-assisted wound closure (EVAC) has been employed with high success rates in decreasing both morbidity and mortality. In the present paper, the authors describe the successful use of Endo-SPONGE (B. Braun Medical B.V.) EVAC system therapy to drain an open rectal wound, following a perforation occurred during stapled hemorrhoidectomy.

Purpose: This study aims to compare the feasibility of VAE and BLES in the treatment of intraductal papillomas. Material and methods: Patients with a suspected intraductal papilloma who underwent a BLES or a VAE procedure were included in this retrospective study. The BLES procedures were performed between November 2011 and June 2016 and the VAE procedures between May 2018 and September 2020 at the Department of Radiology of Helsinki University Hospital (HUH). The procedures were performed with an intent of complete removal of the lesions. Results: In total, 72 patients underwent 78 BLES procedures and 95 patients underwent 99 VAE procedures. Altogether 52 (60%) papillomas with or without atypia were completely removed with VAE, whereas 24 (46%) were completely removed with BLES, p = 0.115. The median radiological size of the high-risk lesions completely removed with BLES was 6 mm (4-12 mm), whereas with VAE it was 8 mm (3-22 mm), p = 0.016. Surgery was omitted in 90 (94.7%) non-malignant breast lesions treated with VAE and in 66 (90.4%) treated with BLES, p = 0.368. Conclusion: Both VAE and BLES were feasible in the treatment of intraductal papillomas. In most non-malignant lesions surgery was avoided, but VAE was feasible in larger lesions than BLES. However, follow-up ultrasound was needed more often after VAE. The histopathologic assessment is more reliable after BLES, as the lesion is removed as a single sample. (C) 2021 The Authors. Published by Elsevier Ltd.

Complications during childbirth result in the need for clinicians to use ‘assisted delivery’ in over 12% of cases (UK). After more than 50 years in clinical practice, vacuum assisted delivery (VAD) devices remain a mainstay in physically assisting child delivery; sometimes preferred over forceps due to their ease of use and reduced maternal morbidity. Despite their popularity and enduring track-record, VAD devices have shown little evidence of innovation or design change since their inception. In addition, evidence on the safety and functionality of VAD devices remains limited but does present opportunities for improvements to reduce adverse clinical outcomes. Consequently in this review we examine the literature and patent landscape surrounding VAD biomechanics, design evolution and performance from an engineering perspective, aiming to collate the limited but valuable information from a disparate field and provide a series of recommendations to inform future research into improved, safer, VAD systems.

In this article, bamboo nonwoven fabric (BF) is introduced as reinforcement into the vinyl ester (VE) matrix for the manufacturing of BF/VE composites through Vacuum Assisted Resin Transfer Mold pr...

Flushing a vacuum-assisted toilet generates noise levels that can be disturbing both to users and those nearby. Peak radiated noise levels correlate with the time when the valve opens and closes, while the noise levels when the valve is completely open are also relatively high. Significant noise ranges between 300 Hz and 3000 Hz. It was hypothesized that increasing the in-tube distance between the flush valve and the bowl in addition to increasing the bend radius of the tube would reduce radiated noise levels. These modifications resulted in a reduction of about 14 dB in the radiated noise during the valve opening and closing in addition to a reduction of about 5 dB while the valve is completely opened. Intermediate results of varying the tube length and bend radius are presented to show their effects on the radiated sound levels. Two tube inserts were designed to fit (1) underneath and (2) behind the toilet in a compact manner. They were tested to show that they maintain noise control performance without modifying any other part of the toilet. © 2020 Institute of Noise Control Engineering.

Purpose To describe the vacuum-assisted mini-percutaneous nephrolithotomy (vmPCNL) technique performed via the 16Ch ClearPetra sheath, to evaluate its outcomes and to analyze intrarenal pressure (IRP) fluctuations during surgery. Methods Data from all consecutive vmPCNL procedures from September 2017 to October 2019 were prospectively collected. Data included patients’ and stones characteristics, intra and peri-operative items, post-operative complications and stone clearance. Patients undergoing vmPCNL from March to October 2019 were submitted to IRP measurement during surgery. Results A total of 122 vmPCNL procedures were performed. Median stone volume was 1.92 cm3. Median operative time was 90 min and median lithotripsy and lapaxy time was 28 min. Stone clearance rate was 71.3%. Thirty-one (25.2%) patients experienced post-operative complications, seven of which were Clavien 3. Postoperative fever occurred in nine (7.4%) patients and one (0.8%) needed a transfusion. No sepsis were observed. IRPs were measured in 22 procedures. Mean IRP was 15.3 cmH2O and median accumulative time with IRP > 40.78 cmH2O (pyelovenous backflow threshold) was 28.52 sec. Maximum IRP peaks were reached during the surgical steps when aspiration is closed (mainly pyelograms), whereas during lithotripsy and suction-mediated lapaxy, the threshold of 40.78 cmH2O was overcome in three procedures. Conclusions vmPCNL is a safe procedure with satisfactory stone clearance rates. Mean IRP was always lower than the threshold of pyelo-venous backflow and the accumulative time with IRP over this limit was short in most of the procedures. During lithotripsy and vacuum-mediated lapaxy, IRP rarely raised over the threshold.

Purpose Despite paucity of data, there exists growing popularity of catheter-based extraction methods for intravascular thrombi and vegetations. We describe a large single center experience with vacuum-assisted extraction techniques (VAET) for right-sided intravascular and cardiac masses. Methods We retrospectively reviewed the perioperative course of patients undergoing VAET between 2014 and 2019. Primary outcomes were survival and freedom from recurrent bacteremia. Procedural success was a composite definition of survival, majority of mass extraction, absence of recurrent bacteremia, and valve function not requiring further intervention during index hospitalization. Results Of the entire cohort (n = 58), 48% and 52% underwent VAET for vegetations and sterile thrombi, respectively. Of those with positive cultures, the most common organism isolated was Staphylococcus aureus (48%). Preoperative active bacteremia was present in 36% (21/58) and of these patients, 76% (16/21) had neither recurrent nor persistent bacteremia post-op. The majority of masses (67%, 38/58) were debulked with an average reduction in size of 42%. Conversion to open surgery occurred in 3.5% (2/58). Intraoperative and 30-day survival were 98% (57/58) and 90% (28/31), respectively. Overall success was 86% (50/58). The prevalence of moderate/severe tricuspid regurgitation was 37% pre-op and 61% post-op. Average length of intensive care unit and overall hospital stay was 5.6 and 16 days, respectively. Conclusions In this single center experience, VAET was conducted safely with a high degree of success and freedom from short-term recurrent bacteremia. This minimally invasive procedure is an attractive alternative to traditional open techniques for removal of right-sided intravascular and cardiac masses.

Vacuum-Assisted Resin Infusion (VARI) and Resin Transfer Molding (RTM) techniques are the most common techniques for the manufacturing of polymeric composite laminates. The VARI technique has a lot of advantages such as low cost, free voids laminates and the ability to produce complex shapes. However, it has some drawbacks such as poor surface finish and temperature instabilities. On the contrary, the RTM technique can withstand high temperature, producing a good surface finish and complex shape laminates. However, it has a high tooling cost and poor quality laminates due to void contents. In this study, a new technique integrated both VARI and RTM techniques is developed to minimize their drawbacks. This technique involves using a semitransparent composite plate instead of a vacuum bag in the VARI technique. This semitransparent plate takes the inverse shape of the composite laminate similar to the RTM tooling. However, this plate has a low cost compared with RTM tooling and allows monitoring of the resin flow during the infusion process. To validate the integrated technique, the mechanical properties of composite laminates are compared with that produced by hand layup technique (HLT). Moreover, the influence of incorporation of 0.25 wt. % and 0.5 wt. % of titanium dioxide (TiO2) nanoparticle into woven and chopped fiber/epoxy composite laminates was demonstrated. The results indicated that the laminates fabricated by the integrated VARI method showed higher mechanical properties than those produced by the hand-layup technique. Moreover, glass fiber/epoxy filled with 0.25 wt. % of TiO2 nanoparticles gives high mechanical properties.

Six kinds of bamboo/glass fiber vinyl ester hybrid composites with different layers were prepared by vacuum assisted resin infusion (VARI) process. The bending and pendulum properties on them, mean...

Carbon fiber reinforced epoxy composite (CFREC) have gained interest due to their high strength to weight ratios. Conventional techniques to fabricate carbon fiber composite come with a limitation of overheating, high cycle time and high cost. The present manuscript is focused to address some manufacturing challenges during microwave curing of CFREC with 10% reinforcement by weight. In the present work microwave curing was done with or without assistance of vacuum pressure. The mechanical behavior of the specimens was studied in terms of tensile strength and hardness. The scanning electron microscopy (SEM) was used to analyze the tensile fractured specimens.

Background Surgical embolectomy and thrombolytic therapy are two common approaches for the treatment of large intra-cardiac or intravascular thrombi to prevent new or worsening pulmonary embolism (PE). Considering high operative mortality with surgical embolectomy and high bleeding risk with thrombolytic therapy, patients who are poor candidates for these treatments may benefit from percutaneous aspiration thrombectomy/Vacuum-assisted thrombectomy (VAT). AngioVac aspiration system was granted 510(k) clearance by the United States Food and Drug Administration (FDA) in April 2009. We present a case series to describe its use and outcomes in evacuating large caval thrombi or intracardiac masses. Methods We did a retrospective analysis of AngioVac catheter based thrombectomy in 16 consecutive patients treated between January 2016 and January 2019 to report case characteristics and in-hospital clinical outcomes. Results Sixteen patients (mean age 48) underwent 16 AngioVac procedures over 48 months. Indications included intracardiac mass (68.8%), caval thrombus (56.3%), and catheter associated thrombus (43.8%). 7 (43.8%) patients had concurrent PE. Peri-procedure mortality was 0% and in-hospital mortality was 12.5% at a mean follow-up of 14 days. There were no pulmonary hemorrhages, strokes or myocardial infarctions. 62.5% had a significant drop in hemoglobin, which required a blood transfusion but there was no episode of overt bleeding. Conclusion The AngioVac aspiration system has been shown to be effective at aspirating large volumes of intravascular and intracardiac thrombus. It is a reasonable alternative to surgical thrombectomy in patients with large central thrombi or masses in-transit who are at risk of complicated PE.