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This work aimed to assess the impact of sonication (US), osmosonication (US + OD) and vacuum-assisted osmosonication (V + US + OD) pretreatments on the quality of Ghanaian garlic prior to relative humidity convective drying. Hence, slices of fresh garlic subjected to US, US + OD and V + US + OD pretreatments were dried and the following assessed: antioxidant activities, total phenolic content (TPC), total flavonoid content (TFC), polyphenol oxidase (PPO) enzyme inactivation, rehydration ratio (RR), drying kinetics, energy consumption, chromatographic fingerprinting, allicin content and Fourier-transform infrared (FT-IR) spectroscopy. V + US + OD pretreatment gave the best results for antioxidant activities, TPC, TFC, RR and PPO enzyme inactivation. It also recorded the shortest drying time and was more energy efficient. Finally V + US + OD pretreatment maintained the chemical integrity of the finished product and recorded the highest content of allicin. A general trend was however observed for all quality parameters assessed for the various pretreatment methods as: V + US + OD > US + OD > US.

BACKGROUND: The objective of the study was to compare direct measurement with a conventional method for evaluation of clip placement in stereotactic vacuum-assisted breast biopsy (ST-VAB) and to evaluate the accuracy of clip placement using the direct method. METHODS: Accuracy of clip placement was assessed by measuring the distance from a residual calcification of a targeted calcification clustered to a clip on a mammogram after ST-VAB. Distances in the craniocaudal (CC) and mediolateral oblique (MLO) views were measured in 28 subjects with mammograms recorded twice or more after ST-VAB. The difference in the distance between the first and second measurements was defined as the reproducibility and was compared with that from a conventional method using a mask system with overlap of transparent film on the mammogram. The 3D clip-to-calcification distance was measured using the direct method in 71 subjects. RESULTS: The reproducibility of the direct method was higher than that of the conventional method in CC and MLO views (P = 0.002, P < 0.001). The median 3D clip-to-calcification distance was 2.8 mm, with an interquartile range of 2.0-4.8 mm and a range of 1.1-36.3 mm. CONCLUSION: The direct method used in this study was more accurate than the conventional method, and gave a median 3D distance of 2.8 mm between the calcification and clip.

Defects in laminated composite structures like voids and impact damages have a major influence on the fatigue behaviour. These defects may occur in the manufacturing process and during lifetime of composite parts and lead to matrix cracks within single layers and to delaminations between adjacent layers with different fibre orientations. We investigated the relationship between voids and impact damage and fatigue lifetime. Specimens made of a glass fibre non-crimp fabric were produced by vacuum assisted resin infusion. Voids were introduced by air-bypass simulating a leakage during the vacuum assisted resin infusion-process. Impact damage was induced using a canon. Stringer-panels with the basic dimensions of 1000 mm × 1200 mm and a radius of 1980 mm were tested under multiaxial load situations in a hexapod test rig and a tension/compression-shear test rig.

This work describes an experimental mechanical characterisation campaign on composites made out of a quasi-unidirectional basalt fabric. In order to evaluate the ability of commercial basalt fabrics and their composites to meet the potentials of basalt fibers, the work has used raw materials from commercial catalogs with no further modification. Two common manufacturing techniques for medium performance composites have been adopted: vacuum assisted resin infusion, and hand-impregnated vacuum bagging. Two panels, one for each technique, have been fabricated, able to provide a sufficient number of samples for a comprehensive stiffness and strength characterization through Tensile, Flexural, In-Plane Shear, Short Beam Shear, Double Cantilever Beam and End-Notched Flexural tests. Results revealed a significant dependence of the mechanical properties on the manufacturing processes, due to their different ability to fully impregnate the dry fabric assembly, and on the quality of fiber/matrix adhesion. In general, hand-impregnation followed by vacuum bag curing was able to guarantee a better impregnation, which in particular yielded superior Interlaminar Shear Strength and Interlaminar Fracture Toughness performances.

Purpose: To explore whether the characteristics of vacuum delivery are associated with the occurrence of head injury and neonatal complications. Methods: Retrospectively cohort study of vacuum-assisted attempted vaginal deliveries of singletons. We studied the association of total duration of vacuum application and number of pulls and cup dislodgement with (1) primary outcome: the occurrence of major (subgaleal hemorrhage, skull fracture, and intracranial hemorrhage) or minor (cephalohematoma, scalp laceration more extensive than simple abrasions) neonatal head injuries and (2) secondary outcome: the occurrence of neonatal complications, including 5-min Apgar score

Vacuum is an assisted technique to improve the efficiency of freeze concentration process, and wine is an interesting raw material to be concentrated. In this study reported the vacuum-assisted block freeze concentration to force the separation of solutes from a frozen wine sample. By applying vacuum (40 kPa), the solids content in the concentrated fraction increased significantly compared to the initial value (8°Brix), reaching a value near of 21°Brix after 5 min, although decreasing over time, indicated that the concentrated extract was collected mostly in the first fractions. The efficiency achieved high values near of 90% in a short time (15 min, 45 ml of initial sample), with high values of ice purity over time of suction. The pH, alcohol, acidity and total polyphenol content increased significantly in the concentrated sample (50% of concentrate) compared the fresh wine. The color evaluation indicating that cryoconcentrate (50% of concentrate) was darker than the initial sample, with a ΔE* value > 40 CIELAB units. The vacuum-assisted block freeze concentration applied to wine is an effective technique to obtain a concentrated sample with attractive properties for possible gastronomic use. Industrial relevance The vacuum assisted block freeze concentration allows producing wine concentrates with attractive properties, such as a high solid content, darker color and higher alcohol content than the initial sample. In this work has applied vacuum (40 kPa) as an assisted technique to improve the efficiency of block freeze concentration applied to wine, obtaining promissory results.

Vacuum infusion experiments with and without distribution medium were carried out in woven E-glass fabric preforms. The experimental set-up was carefully designed to obtain a unidimensional in-plane flow between the inlet and outlet gate, which was combined with through-the-thickness infiltration in the tests carried out with a distribution medium. The variation of the fabric thickness during the infusion experiments was measured by means of digital image correlation, whereas the fluid pressure along the strip was obtained by means of pressure gages. Finally, the in-plane fabric permeability as a function of the fiber volume fraction and the fabric compactability were measured by means of independent tests. The experimental results provided a very detailed picture of the interaction between the fluid infiltration mechanisms and the preform deformation during in-plane and through-the-thickness flow, which is very useful to understand the complex interaction between permeability and compaction during infiltration.

To compare perinatal outcomes of interventions for prolonged second stage of labor.Retrospective cohort study, in a single, university-affiliate, medical center (2007-2014). Eligibility: singleton gestations at term, diagnosed with prolonged second stage of labor and head station of S + 1 and lower. We compared perinatal outcomes of cesarean deliveries (CD) with vacuum assisted deliveries (VAD).Of 62 102 deliveries, 3449 (5.6%) were eligible: 356 (10.3%) underwent CD and 3093 (89.7%) underwent VAD. The rate of five-minute Apgar scores7 was higher in the CD group as well as rates of NICU admission, neonatal asphyxia and composite neonatal adverse outcome. After adjusting for different confounders, CD was associated with adverse neonatal composite outcome (aOR 1.57, 95% CI 1.21-2.05, p = 0.001) and VAD with cephalhematoma (aOR 4.06, 95% CI 2.64-6.25, p 0.001). No other differences were found between the groups with regards to other traumatic outcomes.Our data suggests that in deliveries complicated by prolonged second stage, CD yield poorer neonatal outcome than VAD, with no apparent major difference in traumatic composite outcome.

The recurrence rates of benign phyllodes tumors diagnosed through surgery and ultrasound-guided vacuum-assisted excision (US-VAE) were evaluated. A total of 146 benign phyllodes tumors diagnosed by surgery (n = 126) or US-VAE (n = 20) in 144 patients who had further follow-up after surgery or US-VAE were included (median follow-up period, 32.3 months; range, 6.7-142.5 months). Comparisons of recurrence rate, interval to recurrence, patient age, initial tumor size, Breast Imaging Reporting and Data System category, or follow-up interval were performed between the surgery and VAE groups and between groups with and without recurrence. Three cases (2.1%, 3/146) had recurrence and all were in the surgery group (2.4%, 3/126). The surgery group demonstrated larger size than the VAE group (median, 25 vs 16 mm; P < 0.001). The median age of women in the surgery group was older than those in the VAE group (39 vs 33 years, P = 0.509). The median age of women with recurrence (n = 3) was older than those without recurrence (n = 143, 49 vs 38 years, P = 0.023). In conclusion, when benign phyllodes tumor is unexpectedly diagnosed at US-VAE, if there is no residual lesion at US, clinical follow-up rather than further surgery might be recommended.

In present study, the buckling and crushing behavior of foam-filled glass-fiber reinforced sandwich composite column under edgewise compression were investigated by experimental, theoretical, and finite element analysis (FEA) methods. Various ratios of slenderness columns were manufactured by the vacuum assisted resin injection (VARI) process. A simple theoretical model was introduced to predict the critical collapse load taking into account the various failure modes. A user subroutine VUMAT were implemented in commercial Abaqus software based on the Hashin failure criteria. The geometrical imperfection was considered in FEA model. The experimental results revealed that the critical collapse load would be significantly reduced with the increase of slenderness, especially for the columns with the same length. Through the observing of failure morphologies and the analysis of buckling, it can be found that the first- and second-order buckling mode would play a dominant role in the crushing failure process. The FEA results simulated by present model were in good agreement with the experimental results. The results obtained in present study will be useful for the design and application of foam-filled sandwich composite.

Partially impregnated prepreg are attractive materials for scarf bonded repairs as they can be consolidated with vacuum assisted pressure only. Several air evacuation strategies were evaluated for cobonded scarf repairs of monolithic composites skins. Various void levels were measured in the bondline by digital radiography, and tensile tests were performed to assess the repairs strength recovery. Most of the entrapped air could be evacuated prior to cure for the method using a textured adhesive film. This repair strategy consistently led to a significant reduction in bondline porosity and exhibited the highest strength recovery. Overall, it was found an average linear reduction in tensile strength recovery of 4.5% per 1% areal void content in the adhesive. Additionally, a change in final failure mode was observed from cohesive failure for porous bondlines, to net-section tensile failure in case of void-free bondlines.

For polymer composite product manufacture, curing is a critical step in achieving desired thermal and mechanical properties. The conventional thermal cure processes using hot air ovens and autoclaves are time and energy intensive. Microwave (MW) assisted curing is one of the alternative, most promising methods of curing polymer matrix composites, that could lead to substantial reduction in cure cycle time, energy requirements and operational costs due to its volumetric mode of heating. In the present work, studies were carried out on vacuum assisted microwave curing of glass-epoxy composite laminates using novel, in-house fabricated, silica based microwave susceptible molds inside a conveyor type microwave cure facility. Comparison of the cure process parameters with those of conventional thermally cured composite laminates revealed that vacuum assisted microwave curing resulted in ∼ 90% time savings and ∼ 60% energy savings, thus revealing the dual benefits of microwave processing as well as the novel microwave susceptible molds employed. The temperature uniformity of the molds as well as the curing laminate was assessed using a non-invasive, thermal imaging camera. Cure completion of microwave-cured laminates was ascertained by glass transition temperature (Tg) measurements across the laminates as well as mechanical property determination. Tgs as well as the mechanical properties obtained for vacuum assisted microwave-cured laminates (VMCL) were comparable or superior to those of thermally cured laminates (THCL). POLYM. COMPOS., 2016. © 2016 Society of Plastics Engineers

In this research, a novel method for fabricating flexible polyimide foams was developed. The foam was derived from the precursor synthesized via esterification of 3,3′,4,4′-oxydiphthalic anhydride and 4,4′-oxydianiline. After drying process, the remaining solvent acted as blowing agent. By adjusting the synthesis condition, low-molecular weight precursor was obtained and can be foamed under environment temperature. With this novel type of precursor and vacuum-assisted foaming process, we could easily obtain any shape of foams, which was easy to process under relatively low temperature. The foam could be imidized later in order to improve mechanical strength. During the imidization process, in situ Fourier transform infrared (FTIR) analysis was applied to analyze the variation of the imidization percentage with time. The density of the foams could be adjusted from 12 to 30 kg m−3 with uniform cell structure. Other properties of foams were also investigated. The glass transition temperature of the precursor was 70°C, which is obviously lower than that of the usual previously reported. The 5% and 10% weight loss temperatures of the finally imidized foam can reach up to 567°C and 593°C, respectively. The foams belong to open cell structure with 98% open cell content. The limiting oxygen index of the foams varied from 38.6 to 41.9, depending on foam densities. The compressive strength of the foam ranged from 30.6 to 90.6 kPa when the density changed from 15 to 28 kg m−3. In addition, the in situ FTIR analysis was applied to analyze the imidization percentage of the foam during imidization process.

Recent trends in the application of advanced processing techniques, such as vacuum assisted resin infusion (VARI) or heated vacuum bag only (HVBO), compel generalization of the bond–slip laws for prediction of the interface behaviour in adhesively bonded joints. In this research, a new analytical approach is presented to determine the interface behaviour. Since the model is developed solely based on boundary conditions, it can be applied to any types of the FRP processing technique. With this method, the interface characteristics can be obtained from the applied load at each stage and the properties of the materials. Comparisons between experimental and analytical results of strain, shear stress and slip profiles indicate that the proposed analytical model is capable of predicting the interfacial behaviour between FRP-to-concrete bonded joints manufactured with different the FRP processing techniques (FPTs).

Fibre Metal Laminates have been manufactured by liquid moulding. Flow paths have been drilled to enable the impregnation through the aluminium sheets. The effect of these holes on the low velocity impact behaviour has been studied. Damage mechanisms, dissipated energy and peak force of drilled samples have been compared to those of reference samples without holes. Results show that the presence of the holes has no effect on the performance of the plate and that the internal damage is confined to the surrounding of the impact zone. When the holes are inside the impact contact zone cracks in aluminium sheets propagate through the holes, but their effect is mitigated by the fibre bridging mechanism. Holes located out of the impact contact zone have no effect in the damage mechanisms.

Descending necrotizing mediastinitis (DNM) is a rapidly progressive disease from the spread of cervical infection. Transcervical and transthoracic drainage was the recognized traditional surgical approach to achieve adequate clearance of infection. Non-invasive vacuum-assisted dressing is a new technique where applied negative pressure can help remove infective fluid and to promote wound healing. A 60-year-old man presented with odynophagia, fever and anterior neck swelling for 2 weeks. He was diagnosed to have anterior neck abscess and underwent surgical drainage. However, it did not respond well, but progressed to involve superior and inferior mediastinum. Vacuum-assisted dressing was applied for total of 2 weeks and the patient recovered without going through usual traditional transthoracic drainage. Vacuum drainage is a simple, safe and non-invasive method of managing DNM, in well selected group with small abscess cavity without airway obstruction and septicemia. This potential technique can lead to paradigm shift in treating life-threatening DNM.

In the presented work, the removal process of peel ply from composite surfaces after manufacturing is investigated. Composite specimens are manufactured using the Vacuum Assisted Process (VAP). The required peel force and fracture energy are determined by a peel test corroborated by an analytical model. The fracture energy is correlated to the occurrence of fiber breakouts using drilled samples. The influence of the peel angle and the peel ply orientation are investigated in detail. In preliminary trials they were identified to be of main importance. The peel force of different peel ply products is analyzed. It is observed that a sharp peeling angle and an adaption of the peel ply product to the polymer matrix system are beneficial in reducing defects.

We report a novel vacuum-assisted foaming technique for preparing ultralight glass foams using green spheres as raw material. The green spheres were sintered to form ultralight glass foams under vacuum pressure. The effect of sintering temperature and vacuum pressure on the preparation and properties of glass foams was investigated. The porosity and cell size increased with the decrease of vacuum pressure. Glass foams were fabricated at vacuum pressure of 30–70 kPa, with bulk density, porosity and compressive strength values of 0.081–0.122 g/cm 3 , 95.2–96.8% and 0.29–1.18 MPa, respectively. The ultralight glass foams have potential applications as thermal and acoustic insulation materials.

Background:Lower limb amputation leads to impaired balance, ambulation, and transfers. Proper fit of the prosthesis is a determining factor for successful ambulation. Vacuum-assisted socket systems extract air from the socket, which decreases pistoning and probability of soft-tissue injuries and increases proprioception and socket comfort.Objectives:To investigate the effect of vacuum-assisted socket system on transtibial amputees’ performance-based and perceived balance, transfers, and gait.Study design:Quasi-experimental before-and-after study.Methods:Subjects were initially assessed using their prosthesis with the regular socket and re-evaluated 4 weeks after fitting including the vacuum-assisted socket system. We evaluated the mobility grade using Medicare Functional Classification Level, Berg Balance Scale, Four Square Step Test, Timed Up and Go Test, the 6-Min Walk Test, the Locomotor Capabilities Index, Satisfaction with Prosthesis (SAT-PRO questionnaire), and Houghton Scale.Results:A total of 16 u...

Our aim is to evaluate the capacity of intrapartum translabial ultrasound (ITU) with pushing in the prediction of difficulty of fetal extraction in vacuum assisted deliveries. Prospective, observational study performed (2/2015-8/2015) on 75 nulliparous women, ≥37 weeks with singleton pregnancies at full dilatation who had ITU-with-pushing performed, previous to vacuum-placement for fetal extraction. Working on the translabial sagittal-plane, we assessed: Angle-Progression (AoP), Progression-Distance (PD) and Head-Direction (HD); in the axial plane we evaluated: Midline-Angle (MLA) and Head-Perineum-Distance (HPD). Vacuum extractions were classified as easy-difficulty (ED) (≤3 vacuum-pulls), difficult-unsuccessful (DD) (3 vacuum-pulls). We did not assess occipito-posterior-presentations.Seventy nulliparous were studied (44-ED,26-DD). We observed no differences in obstetric, neonatal or intrapartum characteristics between the two study groups, with the following exceptions: newborn weight (3272 ± 438 g versus 3540 ± 372 g; p = 0.011) and number of vacuum-pulls (1.4-ED-vs-4.4-DD; p 0.0005). AoP-pushing was 143.9° ± 14.6° in ED and 115.1°± 12.9° in DD (p 0.0005); Head-Up was 79.5% versus 38.4% (p 0.0005); PD-Pushing was 42.7 ± 11.3 mm versus 30.4 ± 9.8 mm (p 0.0005); MLA-Pushing was 27.6°± 26.6° versus 57.5°±26.5°(p=0.025); HPD-Pushing was 40.8 ± 10.0 mm versus 47.4 ± 10.9 mm (p = 0.039).We identified that the presence of an AoP-Pushing 128° predicts an Easy-Vacuum-Delivery (≤3 Vacuum-Pulls) in 85% of cases (Sen 80%-FPR 9.3%).

Background: The vacuum-assisted closure was pioneered by Dr Louis Argenta and Dr Michael Morykwas in 1993. It is a development from the standard surgical procedure, which uses vacuum-assisted drainage to remove blood or serous fluid from an operation site to provide a drier surgical field and control blood flow. Methods: We carried out a prospective study of 50 patients on the role of negative pressure wound therapy (VAC) by indigenous method for open wounds cases. Study was conducted during the period from November 2013 to May 2015. Details of cases were recorded including history and wound characteristics. Results: In our study the rate of granulation tissue increases significantly after successive application of VAC and no complications occurred following any VAC dressing. VAC dressing also provided the wound ready for SSG or flap rotation early as assessed by wound bed score. In financial terms VAC dressings by indigenous method is comparable to conventional dressings. Conclusions: Vacuum assisted closure dressing was found to be totally safe. Thus, vacuum assisted closure dressing can be considered as a superior option in the management of chronic wounds. Also compliance of patient is good in vacuum assisted closure therapy.

Carbon fibre reinforced plastics (CFRP) are widely used in all scales from single items to mass products mainly due to their lightweight properties. However, manufacturing of CFRP single items and small batches is highly resource extensive. Mould making is one of the main cost factors. Multipoint tooling replaces the commonly used solid mould with an array of individually adjustable pins to create a desired shape. This shape is then smoothened by an elastic sheet to create a viable tooling surface. This technology has been adapted to various applications from metal stretch forming to thermoforming. In this paper the principal design parameters for multipoint tools are identified and therefrom a concept for CFRP prototype manufacturing is derived. This vacuum assisted multipoint moulding concept modifies the multipoint tooling concept to meet the specific demands of the composite manufacturing process. The general idea behind the technology is to introduce a vacuum to pull the elastic sheet onto the pin array. By evacuating the space underneath the interpolation layer it is pushed on the pin array and therefore enables the creation of convex and concave surfaces in an open mould configuration. To validate the concept, a prototype is built and first moulding tests are conducted. The influence of the interpolation layer in surface quality is evaluated qualitatively. It is found that its thickness has great influence and over a threshold value defect free surfaces can be created. The technology shows the potential to create numerous shapes and enable cost efficient manufacturing of CFRP panels.

Nowadays, automotive, packaging and sport equipment industries are using natural fibre based composite materials as they are cheap, abundantly available and having a lot of ecological advantages. The main objective of this paper is to introduce a new concept of fibre twisting and to investigate the effect of twisting and the fibre orientation on the mechanical properties of bio degradable green composites. Here, the composites are fabricated by vacuum assisted compression molding technique in which the problems of hand lay process are eliminated. Here, two fibers namely twisted neem and twisted kenaf are sandwiched between layers of glass fibres to enhance the stiffness and strength of the laminates. Initially, the fibers are alkalized to increase the mechanical properties. The result shows that there is a significant improvement in mechanical properties of composites due to the presence of twisted fibers. It also shows the influence of fiber orientation on mechanical properties.

Background: This study was performed to evaluate the results of vacuum assisted wound therapy in patients with chronic non healing ulcer. Methods: The study was conducted in the department of General Surgery at a tertiary care hospital. It was an observational study with prospective design. The role of NPWT in various wounds was studied in 10 patients. Results: Out of 10 wounds taken in the study, 7 wounds reduced in area & were resurfaced with Split thickness skin grafting and 3 wounds showed reduction in area & were subjected to secondary closure. Conclusions: Vacuum assisted closure (VAC) therapy provides sterile and controlled environment to large, exudating wound surfaces and is treatment of choice in infected / non – healing wounds, not responding to standard treatment.

The vacuum infusion process is widely used for the manufacture of fiber reinforced polymer composites. Current research concentrates on the comparison of three alternative methods. The aim is to determine if the Membrane Tube Infusion (MTI) and the Vacuum Assisted Process (VAP) that both use membrane fabric are able to produce higher quality laminate compared to the more established Vacuum Assisted Resin Transfer Moulding (VARTM). The laminate quality was evaluated by the void content, fiber volume fraction and mechanical properties. In addition, the thickness was measured in different segments of the laminate in order to determine if the thickness changes along the laminate. The MTI and VAP process did not give a significant improvement of the measured properties, on the contrary, the VARTM outran the aforementioned in many aspects.

Purpose To evaluate the value of ultrasound (US)-guided vacuum-assisted excisional biopsy (VAB) in treating benign phyllodes tumors (PTs) of the breasts and to investigate the lesion characteristics that could affect the local recurrence rate. Patient and methods From December 2008 to February 2018, 93 patients with PTs diagnosed on histology underwent US-guided, 7-gauge VAB. The recurrence rate of benign PT and complications of VAB were evaluated on follow-up US every three to six months. The lesion characteristics were analyzed to identify the factors affecting the recurrence rate. Results Of the 87 patients, local recurrence was found in 15 patients (17%) in a mean follow-up period of 35.8 months, and the rate of complete excision was 82.8% (72/87). PTs with a largest diameter less than 3.3 cm had a significantly lower recurrence rate than PTs with a largest diameter larger than 3.3 cm (P, Highlights • Ultrasound-guided vacuum-assisted excisional biopsy is an effective method for treating benign phyllodes tumors under 3.3 cm. • The lesion dimension of benign phyllodes tumor under 3.3 cm have a low recurrence rate. • Surgical excision was recommended for the recurrence of the benign phyllodes tumors.

Membrane distillation (MD), which uses hydrophobic porous membranes with a temperature gradient to produce pure water, has the potential to treat high-salinity wastewater. However, it cannot directly treat wastewater containing surfactants, which lower the surface tension and thus result in membrane wetting. To overcome this limitation, this study proposed a hybrid process consisting of powdered activated carbon (PAC) adsorption and MD, where PAC removes the surfactants in the wastewater to alleviate the wetting of the MD membranes. A bench-scale vacuum-assisted air gap MD (V-AGMD) equipment was adopted for the treatment of synthetic wastewater containing inorganic salts and surfactants. The conductivity of the permeate from V-AGMD was continuously monitored to detect membrane wetting. Without the use of PAC, the MD membrane was wetted within a short period, which decreased as the surfactant concentration increased. On the other hand, the addition of PAC retards the onset of wetting even at higher surfactant concentrations. The effectiveness of the PAC addition to the MD system on wetting control was examined under various conditions to elucidate its mechanism.

An overlapped repair with a continuous bonding area, was applied to carbon–PPS thermoplastic composites, and their strength recovery rate and failure behavior under mechanical loading were analyzed. This overlapped model has been designed to prevent the common and fundamental failures in conventional repair technologies through utilization of the volume fraction properties of continuous fibers. The same material was used for the parent and repair, and adhesion occurred via reversible thermal properties of the thermoplastic PPS polymer, without using additional adhesives. Under tensile and flexural loading, thickness ratios of 30% and 50% (damaged depth to the total thickness of the laminate) resulted in high strength recovery rates of 96% and 94%, respectively. The overlapped, bonded area on the surface of the parent material is the path of external load transfer between the parent and repair materials, maintaining uniform stress dispersion and increasing the fracture resistance.

Background: Vacuum extraction and forceps are the two options when an instrument is needed to facilitate a vaginal birth. Vacuum extraction has recently gained popularity because of new designs of vacuum cups with reduced risk of injury to the neonate. Vacuum extraction is one of the evidence-based interventions that can prevent complications by shortening the second stage of labour. The present study has been carried out to evaluate the maternal and neonatal morbidity, mortality and failure associated with vacuum assisted vaginal deliveries, at a Government tertiary care hospital in Mandya, Karnataka, India.Methods: The study was a record-based study including a total of 207 women who underwent vaginal assisted delivery in the form of vacuum assisted deliveries in a period of 6 months from January 2019 to June 2019 at the Government tertiary care hospital in Mandya, Karnataka, India. Records of women who had vacuum assisted deliveries and records of their newborn children were accessed.Results: In our study 41.5% of the subjects were in the age group of 21-25 years. Nearly 3/4th (74.4%) of the subjects were primigravida. More than half (54.1%) of the study subjects had to be put under vacuum assisted techniques for delivery because of the prolonged second stage of labour, failure rate was 0.4%. Out of 207 vacuum assisted deliveries maternal complication rate was 8.21%, 17.3% neonates had NICU admission and 14.97% had perinatal complications.Conclusions: Vacuum assisted vaginal delivery is comparatively a better choice in preventing the complications caused due to prolonged second stage of labour thus reducing the cesareans rate. It is a safe alternative to cesareans delivery in rightly chosen case. Vacuum assisted delivery by a skilled person and a proper technique is associated with lesser maternal and neonatal morbidity.

Introduction: Neoadjuvant breast cancer therapy trials have documented impressive rates of pathologic complete response (pCR) of up to 70% and above, depending on grade, hormone receptor and HER2 receptor status and type of therapy. The purpose of our prospective single institution trial is to examine the predictive value of a standardized vacuum assisted core-needle biopsy (VAB) of the tumor site after neoadjuvant therapy with respect to pathologic response status. Methods: From 2011-2017, all patients who had completed neoadjuvant breast cancer therapy at our institution were informed about this trial regardless of their clinical response status. In case of consent, a VAB of the clip-marked tumor site was performed directly before the operation. At least 3, in most cases 6 biopsy cylinders were obtained. Results: A total of 113 patients completing neoadjuvant therapy consented to the trial. Four patients presented with bilateral breast cancer, resulting in 117 cases of breast cancer. The pCR rate (ypT0ypN0) was 36% (n=42). In 14 cases, the biopsy did not show any sign of residual disease, although residual disease was detected upon operation, resulting in an accuracy of 88% for correct prediction of pathologic response. Pre-operative VAB correctly predicted residual tumor in 81%. The negative predictive value was 75%. Conclusions: Although the results of this trial are encouraging, a false negative rate of 19% is entirely insufficient. The method may be useful in guiding decisions regarding the modification of neoadjuvant therapy based on pathological response. Whether or not correct prediction of pathologic response may be improved by further standardizing the tumor marking procedure as well as better defining and increasing the volume of tissue removal by VAB should be examined in a further prospective trial. The omission of operative therapy in case of pCR in a preoperative biopsy after completion of NACT cannot be recommended. Citation Format: Regina Große, Antonia Lebioda, Jana Saegenschnitter, Tin Dao Nguyen, Holger Zentgraf, Joerg Buchmann, Christine Fathke, Susanne Steer, Christoph Thomssen. Vacuum assisted core-needle biopsy after neoadjuvant therapy in breast cancer to predict the status of pathologic response [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-03-01.

A considerable collection of VARTM choices for composite manufacturing techniques can be both found in literature as well as in industry. Each manufacturing process provides different benefits that must be carefully considered depending on the final application of the desired composite. Here, we present a performance comparison in terms of process effectiveness related to fibre volume fraction, the magnitude of thickness variation, and void contents of 16 laminated composites manufactured by different variants of VARTM (DBVI, VAP, and CAPRI) as well as HIPRTM. Non-crimp carbon textile reinforcements and five-harness satin woven carbon textile reinforcements with a PRISM® EP2400 resin system as base constituents are used to produce composite panels. After manufacturing 16 composite panels, an evaluation of the pros and cons of the processing vs properties/performance obtained with each of them is discussed. © 2019 Elsevier Ltd

Purpose: Papillary lesions with no atypia (PLNA) are breast lesions with unknown potential of malignancy (B3). New B3 guidelines published in 2018 by NHS Breast Screening Programme proposed VAE (vacuum assisted

Vacuum assisted resin infusion (VARI) is a process applied to manufacture large structures of composite materials, such as aircraft wing and fuselage skins, but the process parameters are designed by experience or lots of experiments. In this paper, the filling process of VARI for composite fuselage skin was analyzed based on simulation and optimized location of resin inlet ports. Firstly, we made 3D model of fuselage skin and simulated impregnation process. Secondly, we determined the location and quantity of resin inlet ports based on simulation results. The simulations showed that it is advisable to reduce the filing time not only by adding the resin inlet quantity, but also choosing optimal locations.

This study focuses on assessing the lifecycle cost (LCC) of structural components of the 'Samanala' boat used in Sri Lanka in order to identify opportunities in reducing LCC contributions at different stages of lifecycle in boat structures. The research methodology was mainly based on survey data and research literature. The lifecycle cost analysis (LCCA) was conducted in four phases, which include design, production, utilisation and disposal. It was identified that the LCC distribution in design, production, utilisation and disposal phases were 0.70%, 4.27%, 94.89% and 0.14%, respectively. It was concluded that although the contribution of design, production and disposal phases for the total LCC is approximately 5%, the efficiency improvement of design and production phases will contribute approximately 16.63% of significant LCC reduction in the utilisation phase. Consequently, it is recommended to use vacuum assisted resin transfer moulding for boat manufacturing for reducing their weight and LCC.

The subject of this work is an application of CFD for simulation of vacuum assisted resin infusion. The microscale behaviour is neglected and fibres in the mould are replaced by the porous zone. Equations for porosity coefficients are altered so the coefficients can be computed from the experiment’s outputs. The experiment is simplified by filling the mould with fibres without additional layers, which are commonly used in industry manufacturing. There are two experiments. The first one is simple and is used like an input for the simulation. Results of second one are compared with the simulation.

The acoustic emission (AE) method was used to monitor the tensile damage in a 3D braiding composite shaft. The 3D braiding composite shaft was manufactured via Vacuum Assisted Resin Transfer Moulding (VARTM) and the tensile experiment was conducted accompanied by AE monitoring. The AE signals were analyzed using the wavelet transformation for time-frequency analysis. The characteristic values of the AE signals were decomposed by the principal component analysis (PCA). The damage mode of the 3D braiding composite shaft under tension was identified and classified by the fuzzy clustering method (FCM). The results showed that the AE method could monitor the damage evolution process of the 3D braiding composite shaft under tension and the FCM combined with the PCA effectively divided the damage mode of the 3D braiding composite shaft. The results will provide an effective method for health monitoring of the 3D braiding composite shaft within engineering.

There is a paucity of literature on this potentially devastating side effect of vacuum-assisted delivery. We present here a significant subdural haemorrhage associated with tentorial tear following vacuum-assisted delivery that resolved with only supportive medical measures without resulting in any neurological deficits nor delays on thorough examination and formal neuro-developmental assessment.

We use ultrasonic spray-coating to fabricate cesium-containing triple-cation perovskite solar cells with a power-conversion efficiency of up to 17.8%. Our fabrication route involves a brief exposure of the partially wet spray-cast films to a low vacuum, a process that is used to control film crystallization. We show that films that are not vacuum-exposed are relatively rough and inhomogeneous, while vacuum-exposed films are smooth and consist of small and densely packed perovskite crystals. The process techniques developed here represent a step toward a scalable and industrially compatible manufacturing process capable of creating stable and high-performance perovskite solar cells.

Vacuum assisted ex situ lift out may be used for fast, easy, and reproducible plan view specimen preparation. Manipulation of samples via beveled hollow glass probes whose plane of interest is parallel to slotted grids allow for conventional FIB milling for S/TEM analysis.