Wall Perforation Research Articles

New Spheromorphic Problematics Gaparella from the Lower Cambrian of Western Mongolia

From the lower part of the Tommotian Stage of the Lower Cambrian of Western Mongolia, ridge Hevte-Tsakhir-Nuruu described a new problematical sphaeromorhical microfossils Gaparella elenae sp. nov.; a new combination of generic and specific names Gaparella kuanchuanpuensis (Qian, 1977). has been proposed. Despite its very peculiar morphology, the genus Gaparella Missarzhevsky in Missarzhevsky et Mambetov, 1981 is more often mentioned in the list of synonyms of the genus Archaeooides Qian, 1977. The taphonomic variability of Mongolian Gaparella is shown and the morphology is reconstructed: these were hollow spheres, with a perforated double thin wall; between the holes, which were located chaotically on small elevations, a system of canals was developed; the wall may have been organic with an admixture of mineral components. Based on their lifestyle, these fossils were probably planktonic filter feeders. Their level of organization appears to have been consistent with Porifera; most likely these were juvenile forms.

Experimental Investigation of Wave Pressure on Breakwater-Integrated Oscillating Water Column Devices with a Perforated Wall

This study investigates the wave pressure on an Oscillating Water Column (OWC) device, which features a perforated wall positioned in front of the OWC chamber and is integrated with a caisson breakwater. The perforated wall is designed to mitigate wave impacts on the OWC device under storm wave conditions. To achieve this, a series of laboratory experiments were conducted using a 1:25 scale model, considering both regular and irregular waves. Wave pressure measurements and analyses were performed on various configurations to assess the effects of the perforated wall on the wave pressure exerted against the front wall of the OWC chamber and the caisson breakwater. The results indicate that the perforated wall effectively reduces the amplitude of water column oscillations within the OWC chamber during storm conditions, thereby significantly reducing wave pressure on the OWC chamber wall by approximately 14% and on the breakwater by about 20.3%.

Characterization of the acoustic attenuation index of perforated plasterboard ceilings and lining wall and comparison with an empirical model

Perforated plasterboards are known for their absorption performance. Measurements of the sound reduction index R is realized with these boards. Two configurations is tested in laboratory, one configuration of a perforated plasterboard ceiling suspended on concrete floor and a second configuration of perforated plasterboard lining wall fixed on 16cm concrete wall. Following this characterization, a semi-empirical model to estimate the attenuation index is proposed. The perforated board is simulated by considering an heterogeneous board of gypsum and holes related by the perforation rate. The prediction model is compared with the measurement with a good accuracy. Finally, after extrapolations of sound reduction index is proposed for other perforation rates.

Simulating conjugate heat and mass transfer by the advanced perforated wall model for effusion cooling

Full-scale Computational Fluid Dynamics (CFD) numerical simulations can accurately predict the heat flux and metal wall temperature of gas turbine combustor liners, but they require considerable computational resources. In present work, an Advanced Perforated Wall model (A-PWM) has been developed to resolve the flow and heat transfer behaviors in this confined region. The geometric structure of the effusion cooling perforated plate is simplified, while the fluid-solid coupling heat transfer processes are still fully considered in details. The three-dimensional Reynolds Average Navier–Stokes simulations have been carried out for both a single-hole cooling plate and a multi-hole perforated cooling plate by using A-PWM. For simulations of the single-hole cooling plate, the cooling effectiveness in the downstream of the jet flow with the x/D ranging from 2 to 8 predicted by A-PWM shows good agreement with conjugate heat transfer model and experimental results. For multi-hole perforated cooling plate, the differences of cooling effectiveness between the prediction results by A-PWM and experimental results are just within 5%, confirming the developed model’s accuracy in predicting the effusion cooling. In addition, the A-PWM can also be employed to analyze the temperature distribution inside the solid zone. In simulations of both the single-hole cooling plate and the multi-hole perforated cooling plate, the use of the A-PWM model can lead to a reduction of over 35% in grid count compared to the conjugate heat transfer model, significantly reducing the computational time.

Reliability of Chest Wall Perforator Flaps for Breast Reshaping following Massive Weight Loss

Abstract Background Breast deformity following massive weight loss poses a unique challenge inadequately managed by traditional methods. Patients also have considerable lateral and posterior upper trunk tissue surplus. Multiple studies have used chest wall flaps for auto-augmentation with mastopexy to tackle this problem. However, the outcome measures did not include any objective tools to assess the reliability of these flaps. Hence, in this study sono-mammography and breast anthropometric measurements are used for evaluation of the added volume and long-term sustainability of chest wall perforator flaps. Methodology Twenty massive weight loss patients with Pittsburgh Rating Scale score 2-3 underwent mastopexy with autologous augmentation through perforator flaps encompassing lateral chest wall skin. Outcome measures were breast volume, and the presence of fat necrosis on mammography, and direct breast anthropometry. Conclusion All patients showed a consistent increase in volume postoperatively and no fat necrosis in postoperative mammography, reflecting flap reliability over one year of follow-up. All postoperative anthropometric measurements showed improvement in the breast deformities addressed. Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

EP169 - Volume Replacement Perforator Flaps: Introducing a New Service to a DGH Oncoplastic Surgical Unit

Abstract Aims Oncoplastic breast conserving surgery (BCS) has developed to facilitate adequate oncological resection whilst maintaining cosmesis. Volume replacement surgery allows immediate reconstruction with transposition of autologous tissue. One approach is the use of chest wall perforator flaps (CWPF). This increases access for patients to enhanced oncoplastic techniques facilitating BCS, in the setting of larger tumour size, reducing the mastectomy rate in our unit. Our aim was to analyse a series of patients undergoing CWPF in our DGH and determine whether oncological outcomes were comparable to traditional breast conserving surgery. Methods Patients undergoing CWPF reconstruction were identified using theatre records for a period of 12 months (Jan-Dec2023). Data was collected including patient demographics, histopathological findings and post-operative course and treatments. Results A total of seven patients were identified with median age 48 . Range of tumour sizes: 17mm-51mm. All were performed in the immediate setting with all undergoing SLNB. 3/7 required further surgery in the form of re-excision of margins. One patient developed a seroma, requiring aspiration once without further complication. Patient satisfaction is anecdotally high; however, this has not been quantified. Conclusions The utilisation of CWPF within our DGH has shown satisfactory outcomes. Performing these in the immediate setting means some patients have required re-excision of margins and replacement of flaps (similar to local figures for WLE without volume replacement) without impacting patient satisfaction. We advocate that CWPF significantly increases the options available as routine practice for suitable patients. OBCS is possible within the DGH without compromising oncological treatments or cosmesis.

In Vitro Biomechanical Study of Femoral Neck Fracture Fixation with Two or Three Cannulated Screws in Dogs.

To evaluate the in vitro mechanical properties of basilar fractures of the femoral neck stabilized with two or three titanium-cannulated screws in dogs. Ex vivo study. Cadaveric canine femur (n = 21). The bones were divided as follows: Group 1: control (no osteotomy); Group 2: osteotomy and stabilization with two cannulated screws; and Group 3: osteotomy and stabilization with three cannulated screws. All groups were tested with destructive axial compression with load applied to the femoral head. The stiffness, load, and displacement were evaluated at the failure of Group 1, and the yield load and displacement of Groups 2 and 3. The placement of the three cannulated screws was more demanding than two cannulated screws because of the risk of cortical perforation, especially in the trochanteric fossa area. The smaller the width of the femoral neck, the higher the risk of cortical bone wall perforation. The intact control bones were stiffer (674 N/mm) than both the two-screw repair (90 N/mm) and three-screw repair (120 N/mm) groups (p < 0.05). The failure load was greatest for Group 1 (2692 N). The yield loads for Groups 3 and 2 were 586 and 303 N, respectively. There was no difference between groups for displacement. In vitro cadaveric models of femoral neck basilar fractures repaired with three cannulated screws were significantly stronger than two cannulated screws, but the clinical efficacy must be evaluated by comparing them in vitro with noncannulated stainless steel screws.

Gallbladder Perforation as a Complication of Enteric Fever: An Intriguing Case of Acute Abdomen

If not identified and treated right once, gallbladder perforation—a uncommon but dangerousconsequence of acute cholecystitis—can result in significant morbidity and mortality. We describe theexample of a female patient, having 19 years of age, who had a history of constipation. The patient was diagnosed with typhoid fever and underwent imaging studies that revealed gallbladder wall perforation along its postero-inferior aspect with adjacent contained right subhepatic collection. The patient underwent diagnostic laparoscopy and subtotal cholecystectomy. This instance emphasizes how crucial it is to rule out gallbladder perforation while diagnosing acute abdomen in typhoid fever patients. Prompt surgical intervention and early diagnosis can avert major problems and enhance results.

Shear capacity assessment of perforated steel plate shear wall based on the combination of verified finite element analysis, machine learning, and gene expression programming

Shear capacity assessment of perforated steel plate shear wall based on the combination of verified finite element analysis, machine learning, and gene expression programming

Patient Weight and Chemoprophylaxis in Abdominoplasty: Does It Result in More Bleeding Events?

Bariatric surgery has gained popularity in recent decades as an effective treatment for obesity. Abdominoplasty is one of the most often performed aesthetic procedures all over the world. In post-bariatric patients undergoing abdominoplasty, the diameter size and number of the abdominal wall perforators increase proportionally with increased body weight. Postoperative complications that may occur are haematoma, and venous thromboembolism (VTE). In plastic surgery procedures VTE prophylaxis grades vary due to the lack of consensus and clear guidelines. The aim of this study was to explore the frequency of postoperative bleeding and VTE in patients undergoing abdominoplasty and to explore the risk factors associated with major bleeding. A retrospective single-centre study of adult patients who were operated on by abdominoplasty between 2011 and 2020. Chemoprophylaxis including low molecular weight heparin (LMHW) was recommended when the operating time exceeded 2h. A total of 102 patients were included. There were no patients with VTE. Eight patients were re-operated for major haematoma. The weight loss (peak weight to weight before the abdominoplasty) was 14.4kg larger in the re-operation group (p = 0.03). Eighty-eight percent in the re-operation group and 67% in the other group were treated with LMWH (p = 0.43). Multivariable logistic regression showed that with each decrease from the peak in BMIkg/m2 the risk of re-operation for major haematoma was increased by 22% (p = 0.02). Abdominoplasty in patients after massive weight loss has a higher risk of postoperative bleeding. Having a clear protocol for chemoprophylaxis should be considered. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Micro-failure behaviors of mineral crystals in reservoir rocks impacted by abrasive water jet

Abrasive water jet (AWJ) has been widely used in the development of reservoir resources. In the relevant literature, the mechanism of perforation formation by AWJ impacting rocks in different reservoirs, the effect of rock genesis and mineral species during the material removal process, and the location of crack propagation remain unclear, and there is no comprehensive study that investigates the micro failure behaviors of mineral crystals in the rocks. As a result, in this study, we use AWJ to impact reservoir rocks (granite, sandstone, limestone, and shale), the rock damage and the macro morphology of perforations are characterized by Computed Tomography (CT); then the surface features of perforations are obtained by a 3D morphology scanner and the Joint Roughness Coefficient (JRC) is calculated; finally, the micro characteristics of perforations are analyzed by using a polarizing microscope and scanning electron microscope (SEM). The results show that for all four rock types, the perforation wall formed by AWJ presents relatively smooth (JRC: granite-8.2, sandstone-5.9, limestone-8.3 and shale-11.6) and rough (JRC: granite-13.1, sandstone-12.6, limestone-17.5 and shale-18.5) surfaces, with the location of cracks typically developing around the latter. Sedimentary reservoirs being more susceptible to generate cracks along particle cementation boundaries. Moreover, damage and cracks in shale are more likely to extend along the bedding planes. The results clarified the perforation formation mechanism and the crack development areas of AWJ impacting different reservoir rocks.

Morphological diversity of the velamen radicum in the genus Anthurium (Araceae).

Epiphytes develop anatomical features to improve efficiency of the uptake of water and nutrients, such as absorptive foliar scales or a velamen radicum. Despite substantial studies on the occurrence, morphology, development and phylogeny of the velamen, most of the available literature is focused on Orchidaceae, making current knowledge on velamen clearly biased. A recent publication firmly established that velamina are common in Anthurium species. Thus, this study provides further insights by describing velamen morphological characteristics of Anthurium species and classifying them into different velamen types. Furthermore, we investigate if the different velamen morphological traits are clade-specific and phylogenetically conserved within the genus. Using SEM, we performed a morphological study on 89 Anthurium species, describing six micromorphological traits of velamen and exodermis, following traits used to classify Orchidaceae velamen by Porembski & Barthlott (1988). We distinguished nine velamen types, including two that are unique to Anthurium and not similar to any type found in Orchidaceae. Comparing velamen morphology within the phylogenetic tree of Anthurium revealed clear phylogenetic signals. This study provides detailed morphological descriptions among 89 species of Anthurium from the Araceae, and substantially broadens our knowledge of this tissue. However, velamen function has been even less studied, with hardly anything known about functional significance of having secondary cell wall thickening and perforations on velamen cell walls. Therefore, a logical next step would be to connect these anatomical features to their functions.

Effect of perforated wall in controlling the separation due to SWBLI at Mach no. 5 to 9

Abstract The mixed compression scramjet engine intake was numerically simulated to study the characteristic of shock wave induced boundary layer separation leading to the formation of the separation bubble (SB). The analysis employed a 2D-RANS method with SST k-ω turbulence model at different Mach numbers. The intake is designed as a three-ramp intake for improved performance. As the Mach number varies, the size of the separation bubble formed due to the interaction of oblique shock waves with the boundary layer also varies, affecting both intake the efficiency and overall efficiency of the engine. Apart from traditional control techniques, the most preferred bleed technique is incorporated. Localised &amp; distributed bleed techniques are designed and analysed within the intake at different locations. These techniques result in a reduction in the size of the separation bubble within the intake. Establishing perforation in the engine intake also increases the intake efficiency and overall engine performance.

An acute gastric volvulus in a child with congenital left diaphragmatic hernia: a case report

BackgroundAcute complete gastric volvulus is a rare and life-threatening disease, which is prone to gastric wall ischemia, perforation, and necrosis. If it is not treated by surgery in time, the mortality rate can range from 30 to 50%. Clinical presentations of acute gastric volvulus are atypical and often mimic other abdominal conditions such as gastritis, gastroesophageal reflux, gastric dilation, and pancreatitis. Imaging studies are crucial for diagnosis, with barium meal fluoroscopy being the primary modality for diagnosing gastric volvulus. Cases of acute gastric volvulus diagnosed by ultrasound are rarely reported.Case presentationWe reported a rare case of acute gastric volvulus in a 4-year-old Chinese girl who presented with vomiting and abdominal pain. Ultrasound examination revealed the “whirlpool sign” in the cardia region, raising suspicion of gastric volvulus. Diagnosis was confirmed by X-ray barium meal fluoroscopy, which indicated left-sided diaphragmatic hernia and obstruction at the cardia region. Surgical intervention confirmed our suspicion of acute complete gastric volvulus combined with diaphragmatic hernia.ConclusionIn this case, we reported an instance of acute complete gastric volvulus. Ultrasound revealed a “whirlpool sign” in the cardia, which is likely to be a key sign for the diagnosis of complete gastric volvulus.

Abstract PO3-23-06: Short-term clinical and patient-reported outcomes of oncoplastic breast conserving surgery and mastectomy with and without immediate breast reconstruction: The UK ANTHEM multicentre prospective cohort study

Abstract Background: Oncoplastic breast conserving surgery (OPBCS) may allow women with early breast cancer to avoid mastectomy leading to fewer complications and better quality of life. High quality comparative evidence, however, is lacking. The UK ANTHEM study (ISRCTN18238549) aimed to explore the feasibility of undertaking a large-scale multicentre study comparing the clinical and patient reported outcomes (PROs) of OPBCS as an alternative to mastectomy +/- immediate breast reconstruction (IBR) in women offered both options. Methods: Women aged 18 and over with invasive breast cancer or DCIS not suitable for standard breast conserving surgery, who were offered OPBCS as an alternative to mastectomy +/- IBR were eligible to participate in the study. Demographic, operative, oncological data were collected and the numbers of women experiencing complications at 3 months following surgery compared by procedure type. Participants completed the validated BREAST-Q at baseline and 3 months post-operatively. Questionnaires were scored according to the developers’ instructions and scores compared across timepoints by procedure group. Analysis of covariance, adjusting for baseline scores was used to explore factors influencing patient-reported outcomes after surgery. Results: 361 women from 32 UK centres participated in the study. When offered both options, the majority (n=284, 78.7%) elected to undergo OPBCS with either a therapeutic mammaplasty (TM) (n=207, 57.3%) or a chest wall perforator flap (CWPF) (n=77, 21.3%). The remaining 77 (21.3%) women chose mastectomy with (n=40, 11.1%) or without IBR (n=37, 10.3%). Women having mastectomy + IBR were significantly younger than those choosing other procedure types (p=0.002) and those choosing TM had higher BMIs (P=0.008), but there were no other differences between the groups. By 3 months post-operatively, 23.0% (n=83) women had experienced at least one complication, but there were no differences between the groups (p=0.50). The BREAST-Q was completed by 329 (91.1%) and 282 (78.1%) women at baseline and 3 months respectively. Although their scores were initially the lowest, women undergoing TMs reported clinically meaningful and statistically significant increases in ‘Satisfaction with Breasts’ (baseline 53.7 [95% confidence interval [CI] 50.4-57.0] to 3 months 68.9 [95% CI 65.5-72.2], p&amp;lt; 0.001) and ‘Psychosocial Well-being’ scores (baseline 62.1 [95% CI 59.2-65.0] to 3 months 70.4 [95% CI 66.9-73.8] p&amp;lt; 0.001) from baseline to 3 months. Women having CWPF and mastectomy +/- IBR did not report any significant changes in either ‘Satisfaction with Breasts’ or ‘Psychosocial Well-being’ scores over time. ‘Physical Well-being’ scores significantly decreased from baseline to three months in all treatment groups (p&amp;lt; 0.001) but were lowest after mastectomy only (56.5 [95% CI 47.4-65.5]) and highest in the TM group (68.6 [95% CI 65.9-71.3], p&amp;lt; 0.001). ‘Sexual Well-being’ decreased in all groups except for women having mastectomy + IBR. Adjusting for baseline, women undergoing OPBCS with TM (13.2, 95% CI 4.2-22.2, p&amp;lt; 0.001) or CWPF (11.4, 1.6-21.2, p=0.02) reported significantly higher ‘Satisfaction with Breasts’ scores at 3 months than those undergoing mastectomy. Receipt of IBR did not appear to lead to significantly higher scores compared with mastectomy alone (6.47, 95% CI -6.19 to 19.12, p=0.32). Women undergoing TM reported significantly higher ‘Psychosocial’ and ‘Physical well-being’ at 3 months compared with those having other procedure types. Experiencing a post-operative complication resulted in significant decreases in all BREAST-Q domains. Conclusions: When offered OPBCS as an alternative to mastectomy, most women choose breast conservation. This option is safe and appears to be associated with improved short-term PROs, particularly in the TM group. Further work is needed to establish the long-term outcomes of these techniques to support informed decision-making. Citation Format: Charlotte Davies, Leigh Johnson, Carmel Conefrey, Nicola Mills, Patricia Fairbrother, Chris Holcombe, Lisa Whisker, William Hollingworth, Joanna Skillman, Paul White, Douglas MacMillan, Charles Comins, Shelley Potter. Short-term clinical and patient-reported outcomes of oncoplastic breast conserving surgery and mastectomy with and without immediate breast reconstruction: The UK ANTHEM multicentre prospective cohort study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-23-06.

Combination techniques with chest WALL perforator flaps for total breast reconstruction

Combination techniques with chest WALL perforator flaps for total breast reconstruction

AB031. SOH24AB_134. Chest wall perforator flaps: oncological and surgical outcomes in a tertiary referral centre

AB031. SOH24AB_134. Chest wall perforator flaps: oncological and surgical outcomes in a tertiary referral centre

Chest wall perforator flaps for chest wall resurfacing following mastectomy for locally advanced or recurrent breast cancer – A systematic review of the literature and our experience

Chest wall perforator flaps for chest wall resurfacing following mastectomy for locally advanced or recurrent breast cancer – A systematic review of the literature and our experience

Patient-reported outcome measures with chest wall perforator flap reconstruction: The northern health experience

Patient-reported outcome measures with chest wall perforator flap reconstruction: The northern health experience

Surgical and oncological outcomes in 100 consecutive cases of therapeutic mammoplasty - A comparison with chest wall perforator flaps in the management of breast cancers

Surgical and oncological outcomes in 100 consecutive cases of therapeutic mammoplasty - A comparison with chest wall perforator flaps in the management of breast cancers