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Appendicitis is the most common cause of acute abdominal pain requiring surgical intervention; however, it is extremely rare in infants. Its diagnosis and treatment are challenging due to nonspecific clinical signs and symptoms. As a result, delayed or missed diagnosis is common in young children and is associated with an increased risk of perforation and peritonitis. We reported a case of a 4-month-old healthy male child. The patient presented with abdominal distention and fever. After ruling out other possible causes, he was diagnosed with acute appendicitis, which was confirmed by a CT scan. A gangrenous appendix, dilated bowel loops, and free fluid in the abdomen were discovered during surgery. An appendectomy was performed. The appendix in infants has an average length of 4.5 cm compared with 9.5 cm in adults. Infantile appendicitis is considered rare but cases have been documented also in neonates, misdiagnosis rates are high due to rarity in this age group in addition to nonspecific signs and symptoms, which led to a high perforation rate. Ultrasonography can diagnose appendicitis in children with a sensitivity and specificity of 90%-95% without subjecting the child to radiation. A physician should always keep the diagnosis of appendicitis in mind in the infant age group, even though it is rare, as a delay in diagnosis and treatment has been associated with an increased risk of complications including appendicular perforation and peritonitis.

Juvenile dermatomyositis (JDM) is a rare autoimmune disease characterized by chronic inflammation of the skin and muscle vasculature. Loss of nailfold capillary end row loops (ERL) is associated with disease activity. We now present the first report of serious gastrointestinal (GI) events in two JDM patients, both preceded by a precipitous drop in their ERL, which contributes to the consideration of JDM as a member of the vasculitis group of myopathies. These cases demonstrate that the sudden and significant loss of ERL density appears to be a novel and reliable indicator of severe systemic microangiopathy, including gastrointestinal vasculopathy, in selected children with JDM.

We report the optimized wafer-scale fabrication of microporous membranes for applications in the biomedical field such as cell filtration. Existing similar devices can mostly not be integrated on CMOS circuits or mass fabricated. Both is enabled here by the exclusive use of scalable and low temperature microsystems technology methods on silicon wafers. The successfully manufactured devices are characterized with regard to the feasibility of an integrated clogging detection or captured cell counter. The results from electrochemical measurements across the chips match the calculations from a corresponding theoretical model well, verifying the described concept. Further electrical functionalities may thus be integrated into the micromembrane device in the future, equipping it for new applications and allowing a more efficient solution for existing tasks of similar devices.

Purpose: Recent studies have shown that the incidence of glove lesions during arthroscopy is much lower than that during primary and revision arthroplasty. However, the rate of glove damage after knot tying has not yet been systematically recorded. Therefore, the aim of the study was to determine the impact of surgical knot tying on glove integrity. It was hypothesized that knot tying increases the rate of glove damage, especially in arthroscopic surgery, which could be of special relevance in the treatment of rotator cuff tears. Methods: Gloves that were changed immediately before suturing and only worn during knot tying were investigated for their integrity by means of water tightening test according to EN455. A total of 234 gloves from 40 total hip arthroplasties (THAs), 42 total knee arthroplasties (TKAs) and 36 rotator cuff repairs (RCRs) were collected. A bacterial pass-through test (BPTT) on glove lesions was performed under simulated sterile surgical conditions for 3 surgeons after a wear duration of 45 min. Results: Glove damage by knot tying occurred in 25% of THA, 36.6% of TKA and 25% of RCR surgeries. In THA, the pulling hand (PH) was affected in 46.2%, and the main area of damage (15.4%) was detected on the tip of the middle finger; in TKAs the PH was damaged in 75%, and in RCRs the PH was affected in 66.7%, with most of the lesions (20% each) occurring on the tip of the index finger and the ring finger. The BPTT showed Staphylococcus hominis and Bacillus cereus. Conclusion: Intraoperative knot tying causes damage to gloves, which is of special relevance for arthroscopic surgery. Whereas knot tying is only partly responsible for glove damage in arthroplasty, the general rate of glove damage in arthroscopic surgery is low without knot tying. The surgical knot tying process must be understood as a possible damaging impact on the glove. Therefore, single gloving is not recommended, which is especially important in arthroscopic surgery, where double gloving is not yet standard. Level of Evidence: IV. [ABSTRACT FROM AUTHOR]

The objective of this work was to quantify the effect of atmospheric pressure changes on gas transmission through microperforations, in order to understand the role of fluctuations in the atmospheric pressure on the headspace composition of microperforated modified atmosphere packages. A 3D numerical model that considers the spatial-time and pressure dependence of the gas composition was adapted to simulate the gas exchange through microperforations at different fixed pressures and at variable pressure due to atmospheric pressure fluctuations (such as those caused by atmospheric tides or by the development of high and low-pressure systems) or to changes in altitude during land or air transport. The model results were successfully verified with experimental data recorded in an experimental system built to measure the CO 2 exchange through microperforations affected by pressure changes due to weather conditions (the root mean squared error of the CO 2 composition was 0.01%). The results reveal the importance of contemplating the convective flow generated by a change in pressure outside the package. In the simulated routes, the difference in CO 2 concentration between considering the pressure-driven flow and neglecting it is one order of magnitude in a 10-h land transport through a medium mountain route, for a 1250 mL container with a single microperforation of 7420.6 μm2 area and initial CO 2 concentrations on both sides of the hole of 0.05% and 20.95%. The air transport simulations showed that it is not enough to consider the difference in altitude between the cities of origin and destination, but rather all the pressure fluctuations along the route must be included in the model. • Convective flow in a microperforated package induced by external pressure changes. • Model for accurately predicting pressure-driven flow in a package. • Flow through a microperforation influenced by atmospheric pressure fluctuations. • How the local altitude can impact the flow through a microperforated package. • Gas exchange during the land and air transport of a microperforated package. [ABSTRACT FROM AUTHOR]

Iatrogenic colonic perforation (ICP) is one of the rare complication of colonoscopy procedure, which is performed commonly and considered safe. Although ICP is infrequent complication, it is very serious with high morbidity and mortality rate. We report a case of a patient who has a history of Crohn's disease, presented with both intraperitoneal and extraperitoneal colonic perforation that manifest bilateral pneumothorax, pneumomediastinum, pneumoperitoneum, pneumoretroperitoneum, and subcutaneus emphysema after colonoscopy. Radiologic modalities, particularly computed tomography (CT) scan provides immediate, definitive and effective diagnostic information for not only treatment decision but also follow-up process. CT can detect free air that is not always clinically significant and also the presence of micro-perforations and abscess. [ABSTRACT FROM AUTHOR]

Fresh mushrooms have a very short shelf life, of 1 – 3 days because of their high respiration rate and lack of cuticles that protect the plant from external factors. In the case of fresh-sliced mushrooms, they will be more susceptible to spoilage reactions due to the increase in respiration rate as a result of a broader surface area. Conventional packaging materials can not meet the requirements for modified atmosphere packaging of fresh-sliced mushrooms. One of the techniques to extend the fresh-cut produce shelf life is the passive modification of modified atmosphere packaging technology. For highly respiring fresh-cut produce such as fresh-sliced mushrooms, the permeability properties of the polymeric materials might not be enough to provide an equilibrium gas concentration in the passive modification of modified atmosphere technology. In this case, the microperforated packaging materials can be used for passive modification of fresh-cut produce. But the microperforation process needs a design for the application of the appropriate number and diameter of microholes to meet the requirements of passive modified atmosphere packaging. For this reason in this research, the design of the microperforation process to be used in passive modified atmosphere packaging was based on the diameter and the number of microholes, and the shelf life of fresh-sliced mushrooms was determined. The samples were stored at 15 °C/80% RH, and pH, color, weight loss, textural, sensorial, and microbial analysis were performed periodically during storage. It was determined that the empirical equation used in this research can be applied to microperforated packaging design for fresh-sliced mushrooms. The shelf life of the fresh-sliced mushrooms packaged with microperforated packaging material was 8 days, while it was less than 7 days (4, 5, or 6 days) when packaged with non-microperforated packaging material. This result shows that the use of microperforated packaging material is effective in extending the shelf life of fresh-sliced mushrooms.

Appendicitis is the most common cause of acute abdominal pain requiring surgical intervention; however, it is extremely rare in infants. Its diagnosis and treatment are challenging due to nonspecific clinical signs and symptoms. As a result, delayed or missed diagnosis is common in young children and is associated with an increased risk of perforation and peritonitis. We reported a case of a 4-month-old healthy male child. The patient presented with abdominal distention and fever. After ruling out other possible causes, he was diagnosed with acute appendicitis, which was confirmed by a CT scan. A gangrenous appendix, dilated bowel loops, and free fluid in the abdomen were discovered during surgery. An appendectomy was performed. The appendix in infants has an average length of 4.5 cm compared with 9.5 cm in adults. Infantile appendicitis is considered rare but cases have been documented also in neonates, misdiagnosis rates are high due to rarity in this age group in addition to nonspecific signs and symptoms, which led to a high perforation rate. Ultrasonography can diagnose appendicitis in children with a sensitivity and specificity of 90%-95% without subjecting the child to radiation. A physician should always keep the diagnosis of appendicitis in mind in the infant age group, even though it is rare, as a delay in diagnosis and treatment has been associated with an increased risk of complications including appendicular perforation and peritonitis., (© 2024 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

Fresh mushrooms have a very short shelf life, of 1 – 3 days because of their high respiration rate and lack of cuticles that protect the plant from external factors. In the case of fresh-sliced mushrooms, they will be more susceptible to spoilage reactions due to the increase in respiration rate as a result of a broader surface area. Conventional packaging materials can not meet the requirements for modified atmosphere packaging of fresh-sliced mushrooms. One of the techniques to extend the fresh-cut produce shelf life is the passive modification of modified atmosphere packaging technology. For highly respiring fresh-cut produce such as fresh-sliced mushrooms, the permeability properties of the polymeric materials might not be enough to provide an equilibrium gas concentration in the passive modification of modified atmosphere technology. In this case, the microperforated packaging materials can be used for passive modification of fresh-cut produce. But the microperforation process needs a design for the application of the appropriate number and diameter of microholes to meet the requirements of passive modified atmosphere packaging. For this reason in this research, the design of the microperforation process to be used in passive modified atmosphere packaging was based on the diameter and the number of microholes, and the shelf life of fresh-sliced mushrooms was determined. The samples were stored at 15 °C/80% RH, and pH, color, weight loss, textural, sensorial, and microbial analysis were performed periodically during storage. It was determined that the empirical equation used in this research can be applied to microperforated packaging design for fresh-sliced mushrooms. The shelf life of the fresh-sliced mushrooms packaged with microperforated packaging material was 8 days, while it was less than 7 days (4, 5, or 6 days) when packaged with non-microperforated packaging material. This result shows that the use of microperforated packaging material is effective in extending the shelf life of fresh-sliced mushrooms [ABSTRACT FROM AUTHOR]

Jejunal diverticulosis is rare condition that commonly seen in elderly patient. The majority of cases are asymptomatic; however nonspecific abdominal symptoms like abdominal pain, nausea and diarrhea can be seen. Diverticulum perforation leads to generalized or localized peritonitis which may lead to emergency surgical intervention. Diagnosis of Jejunal diverticulosis is often difficult and it is commonly diagnosed incidentally by screening for other purposes. Jejunal diverticulosis is false diverticulum and is believed that Jejunal diverticulosis arises from herniation of the intestinal mucosa and submucosa without a muscle layer. In this report an 88-year-old male patient was admitted to the emergency department with abdominal pain. In abdominal computed tomography (CT) free gas and fluid were observed in the perihepatic area and between the jejunal loops. The patient was taken to emergency operation. During exploration, multiple diverticules were noted in the jejunum. Microperforation area was seen in one of the diverticula. Approximately 50 cm of jejunal segment with diverticulum was resected. The patient was discharged on the sixth day without any remarkable complications. [ABSTRACT FROM AUTHOR]

• A theoretical model was developed to predict the sound absorption of panels with tapered elliptic micro-perforations. • Experimental validation was carried out using impedance tube method. • Present model gives much better predictions than the conventional cylindrical perforation model. • Effects of panel thickness and eccentricity differential on sound absorption are illustrated. • A critical perforation density exists for optimal sound absorption performance. A theoretical model is developed in the present study to predict the spectral characteristics of the sound absorption of solid panels with tapered elliptic micro-perforations backed by a rigid wall cavity. In the model, plane wave propagation is assumed along the length of the perforation in the presence of a viscous boundary layer at the internal wall of the perforation. End impedances are approximated using results in existing literature. Validation is done using impedance tube measurements. It is confirmed that the present tapered elliptic perforation model can give much better agreement with experimental results than the conventional cylindrical perforation model for all micro-perforation configurations tested. Results also suggest the importance of perforation density in controlling the variation of sound absorption of the panel absorbers upon changes in perforation configurations. [ABSTRACT FROM AUTHOR]

A packaging material requires a proper interaction with regard to water vapour transmission between the product and the outside environment. For many fresh food products such as bakery goods, fruits, and vegetables, microperforation is utilised to extend the shelf life of the foodstuff and to provide better food quality. The microperforation potential of five commercial polymeric films has been evaluated using a pulsed fibre laser technique, and significant differences were found between the films in the penetration of the laser beam and in the diameter of the perforation. Breathable polymeric packaging films were prepared with an average laser power of 20 W and a pulse duration of 200 ns. The numbers of holes (80 μm in diameter) in the films were approx. 2000 holes/m2 and 4000 holes/m2. As expected, the number of perforations affected the water vapour transmission (WVT): the WVT was 11 g/m2/d for unperforated film, and 60 g/m2/d for the film with 4000 holes/m2, indicating that the fibre laser can be used successfully for microperforating this type of polymeric films. However, microscopic and microtomographic analyses revealed major differences in hole formation behaviour and in the wall structures of the microperforations. [ABSTRACT FROM AUTHOR]

Micro-scale hole drilling on metallic sheets has been employed in a wide range of personal computing devices, such as smart phones and tablet computers. Laser machining, micro-electro-discharge machining, and chemical etching are the methods used for fabricating micro-scale holes. In this paper, we propose a hybrid sequential stamping and laser machining process. The alignment in the hybrid process is critical, and a patented device called the ball-cone-hole magnet was used in the experiments to achieve an alignment error of less than 1 µm. The fabrication results obtained by laser-only, stamping-only, and the proposed hybrid process were compared. The diameters of inlets and outlets, as well as the cross-section of holes, were compared herein. The surface roughness of the sidewalls’ inside holes was measured. The proposed hybrid stamping and laser machining process provides an alternative fabrication method for the micro-scale hole drilling process with better hole quality than a laser-only machining process. [ABSTRACT FROM PUBLISHER]

The nail plate forms a barrier that limits the effectiveness of drug delivery in the treatment of nail diseases and prevents the outflow of fluid in the case of subungual hematoma formation. Microperforation of the nail plate through laser radiation can increase the effectiveness of drug delivery and ensure the possibility of blood outflow. This study detected and identified the type and threshold of effects that arise from exposing the nail plate to Yb,Er: Glass ( λ = 1.54 μm) and Er:YLF ( λ = 2.81 μm) laser radiation. The rate and efficiency of nail plate ablation by the radiation of these lasers were studied. The effect of the storage time of a freshly extracted nail plate in open air on its ablation rate by Er:YLF ( λ = 2.81 μm) laser radiation was also investigated. The impact of the Yb,Er:Glass and Er:YLF laser pulses on the nail plate caused bleaching, carbonization, ablation with microcrater formation, and microperforation. The laser energy densities W (thresholds) required for these effects were determined. The maximum ablation rate for Yb,Er:Glass laser radiation was 8 μm/pulse at W = 91±2 J/cm, whereas that for Er:YLF laser radiation was 12 μm/pulse at W = 10.5±0.5 J/cm. The maximum ablation efficiency for Yb,Er:Glass laser radiation was 0.1 μm/mJ at W = 10.5±0.5 J/cm, whereas that for Er:YLF laser radiation was 4.6 μm/mJ at W = 5.3±0.3 J/cm. The laser ablation rate depends on the storage time and conditions of the freshly extracted nail plate. For example, when exposed to Er:YLF laser radiation, the laser ablation rate decreased by half from the initial maximum value in 96 h of air storage and returned to the initial value after 1 h of storage in distilled water. [ABSTRACT FROM AUTHOR]

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Methods for creating precise perforations in respiring produce packaging are being increasingly adopted. Knowledge of oxygen transfer through perforated packaging and oxygen distribution in packages is necessary for successful packaging design of fresh produce. An approach to modeling perforated packaging performance was developed using a cylindrical chamber with precision perforations using Fick's second law. The model was simulated using two techniques including Finite Element Method (FEM) using commercially available software and Finite Volume Method (FVM) through programming. Perforations were approximated as a source term in the second method. Both simulation techniques showed trends similar to experimental data. [ABSTRACT FROM AUTHOR]

Three different plastic films of biaxially oriented polypropylene (BOPP), biaxially oriented polyethylene terephthalate (BOPET) and low-density polyethylene (LDPE) were perforated using Nd-YAG laser. Effects of laser pulse energy were examined by varying energies from 50 to 250 mJ where the pulse duration and pulse repetition were kept constant at 10 ns and 1 Hz, respectively. It was found that perforation diameters of all films increased with increasing pulse energies. Observed perforations were different among the three film types. Explanation was contributed to material inherent property and its interaction with laser. Incorporation of an inorganic filler (i.e. silica based anti-blocking agent used in packaging film) of 0.5 wt% into the LDPE films (0.5Si-LDPE) could improve perforation performance for LDPE. This was attributed to an increased thermal diffusivity of the 0.5Si-LDPE film. Commercial BOPET and BOPP films containing 97 microholes/m2 (hole diameter of ~100 µm) showed an improvement in oxygen transmission rates (OTR) of 18 and 5 times that of the neat films without perforation. In the case of perforated 0.5Si-LDPE films having similar perforations of 97 microholes/m2 and perforation diameter of 100 µm, a two-fold increase of OTR was obtained. Gas transmission rates of the microperforated films were measured based on the static method. Measured OTR and CO2TR values of the three films with varying perforation diameters in a range of ~40-300 µm were compared and discussed. Overall results clearly indicate that perforation by laser is an effective process in developing breathable films with tailored oxygen transmission property for fresh produce packaging. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Highlights: [•] Gibberellin and cytokinin were applied to four grape cultivars according to vineyard practices. [•] Rachis browning after harvest was determined by image analysis. [•] None of the PGRs had a consistent effect on rachis quality and rachis thickness did not correlate to browning. [•] Shelf-life to reach 50% browning was determined with grapes in open or covered punnets. [•] Water loss was not the only cause of rachis browning. [Copyright &y& Elsevier]

Background: Endoscopic submucosal dissection (ESD) for colorectal neoplasms is not widely performed because of the high risk of perforation. Perforations are divided into macroperforations and microperforations. Currently, there is a limited amount of clinical data on the outcome of patients with these types of perforations during colonic ESD. The aim of this study was to investigate the clinical outcome of patients who sustained colon perforations during ESD. We also compared the clinical outcome of patients with microperforations and those with macroperforations. Methods: This study enrolled 101 patients with colorectal laterally spreading tumors (LST) who underwent ESD. We retrospectively reviewed their medical records, including patient demographic data and the clinical, endoscopic, and pathologic features. In the cases where perforation had occurred, the course of hospital treatment was analyzed. All ESD-related perforations were divided into macroperforations and microperforations. A macroperforation was defined as a gross perforation that occurred during an ESD procedure and a microperforation was defined by free air visible on X-rays after the procedure. Results: Of the 101 enrolled patients, 9 (8.9 %) developed perforations. The most common tumor morphology was nongranular-type LST (5 of 9 cases, 55.6 %) based on endoscopic examination. Five patients had microperforations and four had macroperforations. All macroperforations were closed primarily by endoclips during ESD. The endoscopic characteristics did not differ between the groups. However, the length of hospital stay and the mean duration of NPO and antibiotic treatments were longer for microperforation patients. All patients had conservative nonsurgical management such as fasting, intravenous antibiotics, and nasogastric tube drainage. Conclusions: The clinical complications for microperforation patients were worse than those for macroperforation patients. However, the clinical prognoses of patients with perforations that occur during colonic ESD are favorable. [ABSTRACT FROM AUTHOR]

A persimmon master packaging system consisting of 8 inner individual primary packages (3 fruit bag each of 30 µm thick microperforated oriented polypropylene (OPP) bag with 3 or 5 microperforations of 59 µm) and outer secondary package (50 µm thick low density polyethylene (LDPE) film liner bag) was designed to allow separation of individual packages from the secondary package at retail display of higher temperature. The master package was placed in the corrugated box, stored for 160 days at 0°C and periodically opened to take out and store individual primary package units further for 5-10 days at 10°C as simulated retail display. The developed system was compared to 5 kg bulk package of 50 µm LDPE film bag and individual fruit package of microperforated 30 µm OPP film in modifying package atmosphere and preserving fruit quality. Individual packages inside master package attained the equilibrated package atmosphere after 62 days at 0°C: O2 concentration of 0.5% and CO2 concentration of 11.3% for inner packages with 3 microperforations; O2 concentration of 0.5% and CO2 concentration of 9.4% for inner packages with 5 microperforations. In master package system removal of outer liner (secondary) packaging and transfer of individual unit (primary) packages to 10°C resulted in higher CO2 accumulation (15.8-22.9%) inside the package and slight increase of O2 concentration (0.7-2.6%). This package atmosphere range high in CO2 concentration seemed to be still in beneficial range. Overall benefits of master packaging system were reduced weight loss, reduced physiological injury particularly in flesh softening and surface blackening, and better retention in firmness and ascorbic acid, and delayed color change during the chilled storage and/or the display condition. [ABSTRACT FROM AUTHOR]

To better handle variable temperature regimes in produce distribution, a master packaging system consisting of a double-layered gas barrier has been applied to fresh king oyster mushrooms. A secondary master package wrapping four individual 350 g packages was designed to be dismantled when moved to the 10°C retail display from the presale storage at 0°C. Different numbers of microperforations (10, 15 and 20) were tested on the inner individual packages as a control variable to create and maintain beneficial modified atmospheric conditions around the mushrooms. The microperforated individual packages could all attain an effective range of modified atmosphere during the two stages of storage at 0 and 10°C while the package with 15 microperforations best reached the desired modified atmosphere of 1 - 3% O2 and 10 - 15% CO2. The individual packages in the master packaging system had better preservation in quality attributes, such as weight loss, mold/yeast count and texture retention, compared with the control perforated packages of a normal atmosphere. [ABSTRACT FROM AUTHOR]

Background: Surgical gloves provide a protective barrier for patients and members of the surgical team. Although glove integrity is important in an era of blood-borne pathogens, little data exist on bacterial passage after glove perforation. This study evaluated the impact of antimicrobial surgical gloves in reducing microbial passage after glove puncture in a model of wound contamination. Methods: Staphylococcus aureus (ATCC 6538) and Brevundimonas diminuta (DSM 1639) were used to prepare a standardized suspension for testing bacterial passage after glove puncture in volunteers wearing single-layer gloves (group A), double-layer gloves (group B), or antimicrobial trilayer gloves (group C). After exposure periods of 5, 10, 30 and 45 minutes, the outer test gloves were removed and microbial passage was measured on the inner surface of the base gloves. Multiple repetitions (5 or 6) were performed at each sampling time. Results: Microbial passage at 5-, 10-, 30-, and 45-minute exposures were analyzed both separately and combined (5 and 10 minutes and 30 and 45 minutes). No difference was observed in microbial passage between group A and group B at the 10-, 30-, and 45-minute exposures for S aureus, whereas a significant reduction in microbial passage was observed in group C compared with group A (P ≤ .05 to < .005) at the 5-, 30-, and 45-minute exposures for both S aureus and B diminuta. When timed groups were combined (5 and 10 minutes and 30 and 45 minutes), a significant reduction (P ≤ .01 to ≤ .005) in microbial passage of S aureus and B diminuta was observed in group C compared with both group A and group B. Conclusion: These findings represent the first evidence that microbial passage across surgical gloves can be reduced significantly using an innovative antimicrobial glove technology. [Copyright &y& Elsevier]

Abstract: Microperforated films (perforation diameter <200μm) are an option for achieving the appropriate gaseous composition in modified atmosphere packaging, especially for fresh-cut products. In this project, static techniques were used to experimentally measure the oxygen and carbon dioxide transmission rates of microperforated films. Twenty nine microperforations of different dimensions (from 40×30μm to 350×110μm) and thickness (from 29 to 57μm) were tested in the project. A potential equation was found to provide a good prediction of the dependence of the O2 and CO2 transmission rates on the perforation area. The data predicted by the equation was compared with those from five other bibliographic models. The empirical equation agrees, within the experimental range, with the modified Fick’s law (considering the total diffusive pass length of a perforation as the sum of the perforation length and end correction term). The predictions of the proposed equation for thicker films and holes of larger dimensions (equivalent radius >3000μm) correspond to those of the empirical models. [Copyright &y& Elsevier]

Abstract: Silicalite-1 micromembranes of approximately 80μm in diameter have been prepared by synthesizing the zeolite material inside a network of perforations created by using a Nd–YAG laser on 75μm thick stainless steel sheets. Several strategies have been introduced here to reduce the thickness of the micromembranes synthesized; among these the most successful involved using a polyamide filling to reduce the volume of the microperforations accessible to the synthesis solution. The density of microperforations could be tailored to prepare arrays of micromembranes of different overall porosity (1.8, 3.7, 6.6 and 7.7%). The micromembranes performed well in the propane/N2 separation, showing a maximum propane/N2 separation factor of 46, at a propane permeance of about 5×10−6 mol/(m2 sPa). [Copyright &y& Elsevier]

Abstract: A procedure permitting the simple determination of the O2 and CO2 permeance of pouches used to pack respiring foods under real conditions is described. It is based on the measurement of the atmosphere changes in pouches filled with a gas mixture whose composition is calculated as a function of the permselectivity of film. The experimental curves ( and ) versus storage duration are submitted to an exponential regression. The exponential coefficients are directly proportional to the O2 and CO2 permeances of the films. The method is designed for microperforated films (permselectivity close to 1), but can also be used to approximate the permeances of non-perforated films. The large variability of the permeances of the microperforated films is due to the heterogeneity of perforation density and diameter. [Copyright &y& Elsevier]

Background: Port-side recurrence after laparoscopic surgery on known and unsuspected gastrointestinal malignancies has been reported. The mechanisms of this type of metastatic spread are poorly understood. For in situ malignancies, microperforation of the viscus by laparoscopic instruments may liberate cells to facilitate malignant cell movement. Methods: Twenty-three patients undergoing laparoscopic cholecystectomy for benign disease were prospectively studied. The laparoscopic fundal grasper was washed with sterile saline at the start and conclusion of surgery. These washings were examined for the presence of mucosal cells as evidence that gallbladder perforation occurred during the operation. Results: No mucosal cells were seen from washings at the start of surgery. Thirteen cases (56%) of perforation or attempted choledochogram were recorded during surgery. Four of these 13 washings contained mucosal cells. One washing was positive for mucosal cells in the absence of perforation or attempted choledochogram. Conclusions: Microperforation of the gallbladder by laparoscopic instruments occurs during laparoscopic cholecystectomy. [ABSTRACT FROM AUTHOR]

Abstract Novel acoustic absorbers were fabricated by the compression and microperforation of the porous metal, which aimed to develop practical acoustic absorbers for the noise reduction. Sound absorbing coefficients of the five investigated acoustic absorbers were measured by the AWA6128A detector according to the standing wave method, and their trends were consistent with normal sound absorption principle of the porous metal absorber and that of the microperforated panel absorber. The results proved that with same length of the cavity, sound absorption performance could be obviously improved by the compression and microperforation. When length of the cavity was 20 mm, average sound absorbing coefficient of the compressed and microperforated porous metal panel absorber in frequency range 100–6000 Hz reached 59.69%, which was superior to that 25.70% of original porous metal absorber and that 31.49% of the microperforated spring steel panel absorber. In the constructed semi-empirical model, a fourth-order polynomial function was treated as the coupling function to express the superposition absorption effect, and its veracity and reliability was validated by two replication experiments. Micromorphology of the compressed and microperforated porous metal panel provided the intuitive explanations to the improvement of its sound absorption performance. Graphical abstract Unlabelled Image Highlights • Novel acoustic absorber was developed for better sound absorption by compression and microperforation of porous metal. • The compressed and microperforated porous metal panel absorber could achieve better sound absorbing coefficient. • The constructed semi-empirical model was validated to achieve optimal acoustic absorber by two replication experiments. • Micromorphology of the proposed acoustic absorber gave intuitive explanations for its sound absorption performance. [ABSTRACT FROM AUTHOR]

Abstract: Diffuse jejunoileal diverticulosis with pneumoperitoneum but without peritonitis is an uncommon but well-documented entity. Cases of jejunoileal diverticular perforation in which the perforation is evident are managed with resection of the diseased bowel and primary anastomosis. In the absence of an intraoperative finding of a perforation or an area of discrete inflammation, copious irrigation and closure of the abdomen is appropriate in cases of diffuse small-bowel diverticulosis. [Copyright &y& Elsevier]

A 45-year-old woman had an Is + IIa laterally spreading tumor (granular type), 30 mm in size, located in the lower rectum. This lesion was removed by endoscopic piecemeal mucosal resection (EPMR) combined with argon plasma coagulation. The area of the defect after EPMR was completely closed with endoscopic clipping to avoid delayed bleeding and perforation. Perforation, such as tearing of the muscle layer, was not recognized during EPMR. However, abdominal radiography, which the authors perform routinely after EPMR, showed free air near the rectum. The patient did not complain of abdominal pain except for anal discomfort, and conservative treatment with antibiotics was selected. The surgeon inserted a tube from the anus to prevent expansion of the rectum and to keep unwanted digestive juices from leaking out from the damaged area. The maximum C-reactive protein level was 17.2 mg/dL 2 days after EPMR, and on day 6 was <1.0 mg/dL. An oral diet was resumed, and the patient was discharged at 8 days after the EMR. [ABSTRACT FROM AUTHOR]