Standard Tip Research Articles

Importance of Media Composition and Explant Type in Cannabis sativa Tissue Culture.

Producing uniform Cannabis sativa (Cannabis) for medicinal/recreational flower production through sexual propagation has been problematic, leading to dominance of clonal propagation from "mother plants" in the cannabinoid industry, which also faces significant limitations. Cannabis tissue culture (TC) methods have been developed to overcome these challenges, but the long-term health and maintenance of Cannabis explants in TC have been largely overlooked in previous studies. The current study focused on the development of an efficient and optimized micropropagation protocol covering the entire process, with a specific focus on the health and performance in the multiplication stage. Multiplication media were formulated hormone-free to avoid longer-term vitrification issues, resulting in single-main-shoot cultures rather than multiple-shoot cultures. This instigated the use of stage II explant types different from the standard shoot tips previously used for multiple shoot cultures. Multiplication media were further improved from the basal salt composition via nitrogen and calcium additives. The optimized protocol was used on eight diverse Cannabis cultivars to test its applicability across various genetic backgrounds. Results indicated that the protocol was effective for conservation purposes across all cultivars and achieved good long-term multiplication rates for some but not all. The outcomes of this study mark a significant stride towards an efficient Cannabis TC methodology ready for more comprehensive industrial applications.

Fenestrated Endovascular Repair Using Short Tipped Distal Components with No Cross Concept to Prevent Crushing of Target Vessel Bridging Stents

To compare and evaluate early and midterm outcomes of a "no cross" novel approach with short tip vs. standard tip introducer systems for all distal components to prevent target vessel bridging stent kink or collapse during fenestrated endovascular aortic repair (FEVAR). A retrospective analysis was conducted on all patients who underwent FEVAR at a tertiary referral centre between October 2016 and July 2022. The inclusion criterion was the use of renal artery fenestrations. Patients who had chronic dissections were included. Endpoints were analysed in two groups comprising the "no cross" group and the standard group, with all cases being consecutive in their respective groups. Cone beam computed tomography was used intra-operatively in all cases, and post-operative compute tomography angiograms and re-interventions were reviewed. Primary endpoints included technical success, intra-operative adjunctive procedures, adverse events related to the fenestration, and re-interventions, while secondary endpoints were secondary interventions and overall mortality. A total of 70 patients (35 in each group) were enrolled in the study, with 64 (91%) having juxta-renal aneurysms. There were no differences in demographics, cardiovascular risk factors, or aneurysm characteristics between the two groups. The "no cross" group demonstrated a significantly higher technical success rate (100% in all cases) compared with the standard group (29 cases, 83%; p = .010). Additionally, there were statistically significantly fewer intra-operative adjunctive procedures required in the "no cross" group (1.5% of fenestrations) compared with the standard group (8.2% of fenestrations) (p = .013). Overall median follow up was 32 months (interquartile range 22, 62 months). Implementation of a novel "no cross" concept during FEVAR, utilising a short dilator introducer tip on the distal bifurcated component and iliac extensions, significantly reduces intra-operative fenestration related adverse events and enhances technical success. Further studies with larger patient populations and longer follow up are needed to confirm these findings.

24. CRITICAL IMPORTANCE OF NOZZLE TEMPERATURE TO BIOPRINT VASCULAR GRAFTS WITH SHEAR-THINNING HYDROGEL

Abstract Introduction The development of vascular grafts adapted to the nature of the patient and their treatment is constantly evolving. Fine control of the bioprinting manufacturing process is a key issue to obtain proper personalized vascular grafts. The aim is to check the influence of the nozzle temperature during bioprinting a Gelatin/Gellan Gum/Alginate hydrogel vascular grafts. Methods Vascular grafts were printed using a Gelatin/Gellan Gum/Alginate (8:3:0.5 %w/v) hydrogel in an BioX bioprinter with the printhead and bed set up to 65 °C. Two configurations were set: 1) a standard conical tip (nozzle) and 2) the same nozzle thermally insulated with aluminum foil to uniformly distribute the temperature. A temperature control using a 100 kΩ thermistor was performed in four points: chamber, nozzle, printhead, and bed. Four heating/cooling cycles were performed in each control point. Results The grafts printed with the standard nozzle exhibited irregular wall thickness and an uneven surface, attributed to lower temperatures in the conical tip. In contrast, results from the aluminum-covered nozzle indicated temperature distributions of 33.13±0.87, 49.03±3.92, 52.38±3.53, and 64.98±0.10 °C for chamber, nozzle, printhead, and bed, respectively. This improved temperature distribution enhanced the printability of Gelatin/Gellan Gum/Alginate vascular grafts, resulting in a more regular wall thickness and surface profile. Conclusion The optimization of temperature in the nozzle during the printing process is a critical parameter for bioprinting vascular grafts using this shear-thinning Gelatin/Gellan Gum/Alginate hydrogel.

Focused Helium Ion and Electron Beam-Induced Deposition of Organometallic Tips for Dynamic Atomic Force Microscopy of Biomolecules in Liquid.

We demonstrate the fabrication of sharp nanopillars of high aspect ratio onto specialized atomic force microscopy (AFM) microcantilevers and their use for high-speed AFM of DNA and nucleoproteins in liquid. The fabrication technique uses localized charged-particle-induced deposition with either a focused beam of helium ions or electrons in a helium ion microscope (HIM) or scanning electron microscope (SEM). This approach enables customized growth onto delicate substrates with nanometer-scale placement precision and in situ imaging of the final tip structures using the HIM or SEM. Tip radii of <10 nm are obtained and the underlying microcantilever remains intact. Instead of the more commonly used organic precursors employed for bio-AFM applications, we use an organometallic precursor (tungsten hexacarbonyl) resulting in tungsten-containing tips. Transmission electron microscopy reveals a thin layer of carbon on the tips. The interaction of the new tips with biological specimens is therefore likely very similar to that of standard carbonaceous tips, with the added benefit of robustness. A further advantage of the organometallic tips is that compared to carbonaceous tips they better withstand UV-ozone cleaning treatments to remove residual organic contaminants between experiments, which are inevitable during the scanning of soft biomolecules in liquid. Our tips can also be grown onto the blunted tips of previously used cantilevers, thus providing a means to recycle specialized cantilevers and restore their performance to the original manufacturer specifications. Finally, a focused helium ion beam milling technique to reduce the tip radii and thus further improve lateral spatial resolution in the AFM scans is demonstrated.

Efficacy of sample collection without virus transport medium in suspected enteroviral infections for molecular diagnosis.

Clinical swabs with suspected viral infection are usually transported in virus transport medium (VMT). During epidemics/pandemics, tampons without VTM would be more suitable for saving space and cost. This study was conducted to verify the applicability of throat swabs without VTM in the diagnosis/screening of enteroviral infections by polymerase chain reaction (PCR) in avolunteer study group. Three different swab types were used in 40 volunteers: swabs with two different tips (cotton- or synthetic-tipped) without VTM and standard synthetic tips with VTM. The swabs were processed immediately or after 12 days of storage at either -80°C or +4°C. The molecular analysis included viral RNA extraction, and combination of reverse transcriptase PCR and nested PCR. Enteroviral RNA was detected in 15% (6/40) of the studied volunteers. When processed immediately, the results for all three swab types were compatible. Swabs without VTM may be used for collection of clinical samples in the diagnosis of suspected enteroviral infections or as potential screening tools for enteroviruses (Tab. 2, Ref. 15). Keywords: enterovirus infection, swab, transport medium, PCR, molecular diagnostics.

Generation of high-order optical vortices with nanostructured phase masks

We report theoretical and experimental studies on generation of high-order optical vortex beams using fiber-based nanostructured gradient index converters. The components were made of two types of in-house developed soft glasses with lead, bismuth, gallium compositions to ensure the high refractive contrast of the synthesized glasses. As a result, the vortex components, fabricated using the stack-and-draw method, allow converting Gaussian beam into vortex beams with high-order topological charges in the visible and near-infrared regions. We experimentally verified the formation of optical vortex beams with topological charge up to 5 by using the free-space binary-nanostructured vortex components. In addition, the vortex converter integrated into the standard fiber tip generated optical vortex beams with topological charge up to 4.

A node-splitting lattice spring model coupled with a J-integral formulation as a fracture criterion

A global energy minimization criterion based on Griffith’s theory is introduced for the node-splitting lattice spring model. The fracture criterion is computed by both direct numerical simulations of energy release rate G and through a J-integral formulation for comparison and validation. For mode I fractures, the standard implementation of J-integral formulation yields very good estimations of the energy release rate, but for mixed mode fracture the estimations deviates from the direct calculated energy release rate. The reasons for this discrepancy are elucidated and an approach to best approximate the J value is given. This method is compared with the more standard maximum tip stress threshold crack criterion, and shows a much better prediction of the energy release rate and is more robust under grid refinement.

On the layer crossing problem for a semi-infinite hydraulic fracture

This paper analyses the problem of a semi-infinite fluid-driven fracture propagating through multiple stress layers in a permeable elastic medium. Such a problem represents the tip region of a planar hydraulic fracture. When the hydraulic fracture crosses a stress layer, the use of a standard tip asymptotic solution may lead to a considerable reduction of accuracy, even for the simplest case of a height-contained fracture. In this study, we propose three approaches to incorporate the effect of stress layers into the tip asymptote: non-singular integral formulation, toughness-corrected asymptote, and an ordinary differential equation approximation of the non-singular integral formulation mentioned above. As illustrated in the paper, these approaches for stress-corrected asymptotes differ in computational complexity, the complexity of implementation, and the accuracy of the approximation. In addition, the size of the validity region of the stress-corrected asymptote is evaluated, and it is shown to be greatly reduced relative to the case without layers. In order to address the issue, the stress relaxation factor is introduced. This, in turn, allows for enhancing the accuracy of the layer-crossing computation on a relatively coarse mesh to utilize the stress-corrected asymptote in hydraulic fracturing simulators for the purpose of front tracking.

Method to Measure Surface Tension of Microdroplets Using Standard AFM Cantilever Tips.

Surface tension is a physical property that is central to our understanding of wetting phenomena. One could easily measure liquid surface tension using commercially available tensiometers (e.g., Wilhelmy plate method) or by optical imaging (e.g., pendant drop method). However, such instruments are designed for bulk liquid volumes on the order of milliliters. In order to perform similar measurements on extremely small sample volumes in the range of femtoliters, atomic force microscope (AFM) is considered as a promising tool. It was previously reported that by fabricating a special "nanoneedle"-shaped cantilever probe, a Wilhelmy-like experiment can be performed with AFM. By measuring the capillary force between such special probes and a liquid surface, surface tension could be calculated. Here, we carried out measurements on microscopic droplets with AFM, but instead, using standard pyramidal cantilever tips. The cantilevers were coated with a hydrophilic polyethylene glycol-based polymer brush in a simple one-step process, which reduced its contact angle hysteresis for most liquids. Numerical simulations of a liquid drop interacting with a pyramidal or conical geometry were used to calculate surface tension from the experimentally measured force. The results on micrometer-sized drops agree well with bulk tensiometer measurement of three test liquids (mineral oil, ionic liquid, and glycerol), within a maximum error of 10%. Our method eliminates the need for specially fabricated "nanoneedle" tips, thus reducing the complexity and cost of measurement.

Multipurpose active scanning probe cantilevers for near-field spectroscopy, scanning tunnel imaging, and atomic-resolution lithography

In this work, we report progress on developing a multipurpose scanning probe cantilever applying gallium nitride nanowires as the probe tip. Gallium nitride nanowires possess high potential as probes due to their straight profile, tunable electrical and optical properties, high Young’s Modulus, durability, and high-yield fabrication process. Their wide bandgap enables them to be pumped to emit ultraviolet pulses which can be used for optical imaging and spectroscopy. They can be doped during growth to be electrically conductive, and their sharp tips obtained during epitaxial growth enable confinement of a high electric field at tip–sample interface. Their sharp tips are obtained during fabrication by their epitaxial growth which eliminates the need for postprocess sharpening that is typically required for standard STM tips. We present results of using gallium nitride nanowires for scanning tunnel microscopy applications of atomic-resolution imaging and lithography, and atomic force microscopy applications of imaging and lithography in vacuum and atmospheric environments.

Large Range Atomic Force Microscopy with High Aspect Ratio Micropipette Probe for Deep Trench Imaging.

Atomic force microscopy (AFM) has been adopted in both industry and academia for high-fidelity, full-profile topographic characterization. Typically, the tiny tip of the cantilever and the limited traveling range of the scanner restrict AFM measurement to relatively flat samples (recommend 1µm). The primary objective of this work is to address these limitations using a large-range AFM (measuring height >10µm) system consisting of a novel repairable high aspect ratio probe (HARP) with a nested-proportional-integral-derivative (nested-PID) AFM system. The HARP is fabricated using a reliable, cost-efficient bench-top process. The tip is then fused by pulling the end of the micropipette cantilever with a length up to hundreds of micrometers and a tip diameter of 30nm. The design, simulation, fabrication, and performance of the HARP are described herein. This instrument is then tested using polymer trenches which reveals superior image fidelity compared to standard silicon tips. Finally, a nested-PID system is developed and employed to facilitate 3D characterization of 50-µm-step samples. The results demonstrate the efficacy of the proposed bench-top technique for the fabrication of low-cost, simple HAR AFM probes that facilitate the imaging of samples with deep trenches.

A power Doppler ultrasound method for improving intraoperative tip localization for visually obstructed needles in interstitial prostate brachytherapy.

High-dose-rate (HDR) interstitial brachytherapy (BT) is a common treatment technique for localized intermediate to high-risk prostate cancer. Transrectal ultrasound (US) imaging is typically used for guiding needle insertion, including localization of the needle tip which is critical for treatment planning. However, image artifacts can limit needle tip visibility in standard brightness (B)-mode US, potentially leading to dose delivery that deviates from the planned dose. To improve intraoperative tip visualization in visually obstructed needles, we propose a power Doppler (PD) US method which utilizes a novel wireless mechanical oscillator, validated in phantom experiments and clinical HDR-BT cases as part of a feasibility clinical trial. Our wireless oscillator contains a DC motor housed in a 3D printed case and is powered by rechargeable battery allowing the device to be operated by one person with no additional equipment required in the operating room. The oscillator end-piece features a cylindrical shape designed for BT applications to fit on top of the commonly used cylindrical needle mandrins. Phantom validation was completed using tissue-equivalent agar phantoms with the clinical US system and both plastic and metal needles. Our PD method was tested using a needle implant pattern matching a standard HDR-BT procedure as well as an implant pattern designed to maximize needle shadowing artifacts. Needle tip localization accuracy was assessed using the clinical method based on ideal reference needles as well as a comparison to computed tomography (CT) as a gold standard. Clinical validation was completed in five patients who underwent standard HDR-BT as part of a feasibility clinical trial. Needle tips positions were identified using B-mode US and PD US with perturbation from our wireless oscillator. Absolute mean±standard deviation tip error for B-mode alone, PD alone, and B-mode combined with PD was respectively: 0.3±0.3mm, 0.6±0.5mm, and 0.4±0.2mm for the mock HDR-BT needle implant; 0.8±1.7mm, 0.4±0.6mm, and 0.3±0.5mm for the explicit shadowing implant with plastic needles; and 0.5±0.2mm, 0.5±0.3mm, and 0.6±0.2mm for the explicit shadowing implant with metal needles. The total mean absolute tip error for all five patients in the feasibility clinical trial was 0.9±0.7mm using B-mode US alone and 0.8±0.5mm when including PD US, with increased benefit observed for needles classified as visually obstructed. Our proposed PD needle tip localization method is easy to implement and requires no modifications or additions to the standard clinical equipment or workflow. We have demonstrated decreased tip localization error and variation for visually obstructed needles in both phantom and clinical cases, including providing the ability to visualize needles previously not visible using B-mode US alone. This method has the potential to improve needle visualization in challenging cases without burdening the clinical workflow, potentially improving treatment accuracy in HDR-BT and more broadly in any minimally invasive needle-based procedure.

Initial forces acting on the maxillary teeth with aligner activation of canine distalization on the basis of different initial canine tips in vitro

The objective of this study was to investigate the 3-dimensional forces exerted on the maxillary teeth with aligner activation of maxillary canine distalization on the basis of different initial canine tips invitro. A force/moment measurement system was used to measure the forces exerted by the corresponding aligners with the same activation of 0.25 mm for canine distalization on the basis of the 3 initial canine tips. The 3 groups included: (1) group T1, with canine inclined mesially 10° on the basis of the standard tip; (2) group T2, with canine maintained standard tip; and (3) Group T3, inclined distally 10° on the basis of the standard tip. A sample size of 12 aligners was tested for each of the 3 groups. The canines were subjected to distomedial forces and labiolingual and vertical components, which are minimal in group T3. As the anterior anchorage for canine distalization, the incisors were mainly subjected to labial and medial reaction forces, with the most significant reaction forces in group T3, and the lateral incisors were subjected to greater forces than the central incisors. The posterior teeth mainly received medial forces, which were greatest when the pretreatment canines were distally tipped. The forces on the second premolar are greater than those on the first molar and the molars. The results demonstrate that attention to the pretreatment canine tip is necessary when performing canine distalization with aligners, and further work, both invitro and clinically based, investigating the effect of the canine initial tip on maxillary teeth during canine distalization would greatly aid in better treatment protocol with aligners.

Wind Turbine Fatigue Load Analysis for Derating Control Strategies Aimed at Grid Balancing

With the exponential growth of wind energy worldwide, wind power plant owners are eager to participate in grid balancing, in order to compete with traditional power plant owners. In this way, they take part in frequency control which notably amounts to reacting to grid faults by an adequate injection of power. The latter calls for power reserve. For wind farms, this is achieved by derating methods which consist in extracting from the wind less power than the available power, in order to be able to increase the produced power when needed. The objective of this paper is to compare two wind turbine (WT) derating methods in terms of lifetime damage equivalent load (DEL). The first strategy is based on a modification of the generator torque set point to achieve derating, while keeping the standard pitch angle control. The second strategy achieves derating by pitch control while keeping the standard tip speed ratio set point. Both strategies were simulated in OpenFAST under various wind conditions covering all the WT operating regions. Focusing on having a constant power reserve, the simulation results on a single WT show that the pitch-based strategy is the best, among the two considered ones, when it comes to derating while reducing lifetime DEL.

OPTIMIZATION OF POWER-ASSISTED ADENOIDECTOMY IN CHILDREN USING SHAVER TIPS OF VARIOUS MODIFICATION.

The aim: To study the efficacy of surgical treatment of patients with adenoid vegetations by implementing a differential method for choosing a tip for endo-scopic power-assisted adenoidectomy in children depending on dentition. Materials and methods: We investigated the presence of nasal air emissions in 127 children (2-12 years old) before and after the operation. We excluded 12 patients due to the presence of nasal air emission before the operation. All patients were divided in 2 groups: I - children with aging primary dentition (55 children), II- children with mixed dentition (60 children). Depending on tips, that were used for the operation, we divided patients into two subgroups: A - 40˚ and B- 60 ˚. Results: In 9,4% of patients have the presence of nasal air emissions before the operation. The use of 40˚ tips does not allow removal of lymphoid tissue in "hard-to-reach" areas of the nasopharynx (perichoanal and peritubular sections) in 30% of children with aging primary dentition and 42.9% with mixed dentition. Conclusions: The use 40˚ tips for the adenoidectomy is accompanied by a higher risk of velopharyngeal insufficiency in children with mixed dentition compared to children who underwent the intervention with a tip with a larger bending angle and a longer working part (60°). In patients with temporary dentition, it is recommended to use a standard tip for adenoidectomy, except when correction of tubal lymphoid tissue is planned (it is necessary to use a tip with a rotating window). In patients with mixed dentition, it is recommended to use a 60° tip.

Scanning probe lithography on Ge(111)-c(2×8) surface

The paper describes nanometer scale lithography on atomically clean Ge(111)-c(2×8) surface performed in the ultra-high vacuum scanning tunneling microscope operating at 300 K. Using a standard Pt80Ir20 probe tip and applying bias voltages between 0.5 and 3 V, the Ge surface could be reliably imaged with atomic resolution without any modification of the sample. However, surface modification in highly localized area under the probe tip was observed at the bias voltages from 4 to 5 V. Such modification could occur in the form of the deposition of the tip material onto the scanned area of the sample, extraction of the sample material or generation of defects in the sample crystalline structure. Possible physical mechanisms of the processes outlined above as well as the strategies to achieve reliable scanning probe nanolithography are discussed.

Standard and flexible tip bougie for tracheal intubation using a non‐channelled hyperangulated videolaryngoscope: a randomised comparison#

Bougie impingement during tracheal intubation can increases the likelihood of prolonged intubation time, failed intubation and airway trauma. A flexible tip bougie may overcome this problem, which can occur when using a non-channelled, hyperangulated videolaryngoscope with a standard bougie. This randomised controlled study compared standard and flexible tip bougies using a non-channelled videolaryngoscope (C-MAC® D-blade) in 160 patients. The primary outcome measure was the modified intubation difficulty scale score. Secondary outcome measures were: laryngoscopy time; total tracheal intubation time; first attempt success rate; and postoperative sore throat verbal rating score. The median (IQR [range]) modified intubation difficulty scale scores for standard bougie and flexible tip bougie were 1 (0-2[0-5]) and 0 (0-1[0-3]), respectively (p = 0.001). There was no significant differences in laryngoscopy time, total tracheal intubation time, first attempt success rate and postoperative sore throat between the two groups. Both the flexible tip and standard bougies can be used with a high first attempt success rate for tracheal intubation using a C-MAC D-blade videolaryngoscope. The flexible tip bougie demonstrated a significantly better modified intubation difficulty scale score and lower incidence of bougie impingement.

In vitro effect of different implant decontamination methods in three intraosseous defect configurations.

This in vitro investigation was aimed to evaluate the cleaning ability of four mechanical devices designed for decontaminating implant surfaces. Ninety-six implants were coated with permanent ink and inserted into 3D-printed resin blocks simulating three different intraosseous defect configurations (types Ib, Ic, and Ie). The four tested mechanical decontamination devices (air-polishing with glycine powder, rotating titanium brush, polyetheretherketone [PEEK]-coated ultrasonic tip, and stainless steel ultrasonic tip) were randomly applied onto the 5 mm exposed implant surface. Standardized photographs were taken from a frontal perspective and with a 30° angle coronally and apically to the implant axis. The area with remnant ink on the implant surface was calculated. Although none of the groups achieved complete ink removal, air-polishing with glycine and titanium brushes demonstrated a higher cleaning ability when compared with ultrasonic devices either with standard or PEEK tips for all three defect configurations. For the three tested models, the best cleaning ability in all groups was shown on implant surfaces without facing an intraosseous wall. Titanium brush was the most effective when the intraosseous walls existed. Cleaning effectiveness diminished in the threads located in the apical third, especially when using air-polishing and ultrasonic devices. Titanium brushes and air-polishing devices were more effective in removing artificial biofilm using this in vitro model, although their effectiveness was influenced by the presence of the intrabony component.

In vitro testing of a funnel-tip catheter with different clot types to decrease clot migration in mechanical thrombectomy.

Mechanical thrombectomy is the standard treatment for acute ischemic stroke in patients with large vessel occlusion and can be performed up to 24h after symptom onset. Despite high recanalization rates, embolism in new territories has been reported in 8.6% of the cases. Causes for this could be clot abruption during stent retrieval into the smaller opening of a standard distal access catheter, and antegrade blood flow via collaterals despite proximal balloon protection. A funnel-shaped tip with a larger internal diameter was developed to increase the rate of first-pass recanalization and to improve the safety and efficacy of mechanical thrombectomy. This in vitro study compared the efficacy of a funnel-shaped tip with a standard tip in combination with different clot compositions. Mechanical thrombectomy was performed 80 times for each tip, using two stent retrievers (Trevo XP ProVue 3/20 mm, 4/20 mm) and four different clot types (hard vs. soft clots, 0-24h vs. 72h aged clots). Significantly higher first-pass recanalization rates (mTICI 3) were observed for the funnel-shaped tip, 70.0% versus 30.0% for the standard tip (absolute difference, 32; relative difference 57.1%; P < .001), regardless of the clot type and stent retriever. Recanalization could be increased using harder Chandler loop clots versus softer statically generated clots, as well as 0-24h versus 72h aged clots, respectively. The funnel-shaped tip achieved higher first-pass recanalization rates than the smaller standard tip and lower rates of clot abruption at the tip. Clot compositions and aging times impacted recanalization rates.

Preparation of thermostable polypropylene membranes with a controlled structure by nonsolvent thermally induced phase separation

ABSTRACT The nonsolvent thermally induced phase separation (N-TIPS) method is used to prepare flat sheet polypropylene membranes. The morphology and performance of the membranes prepared by standard TIPS and N-TIPS are compared. The effect of some parameters of membrane preparation process such as polymer concentration in dope solutions, thermodynamic affinity between the polymer and cosolvent and gap height in the film-casting device on the membrane structure and properties is investigated. The membrane properties can be controlled over a range of permeability values from 0.3 to 48 m3m–2h–1 bar–1 and mean through pore size from 0.22 to 0.55 μm.