Common Channel Research Articles

EXPRESS: Beyond the Pair: Media Archetypes and Complex Channel Synergies in Advertising

Prior research on advertising media mixes has mostly focused on single channels (e.g., television), pairwise cross-elasticities, or budget optimization within single campaigns. This is starkly detached from advertising practice where (i) there is an increasingly large number of media channels available to marketers, (ii) media plans employ complex combinations of channels, and (iii) marketers manage complementarities among many (i.e., more than pairs) channels. This research empirically learns complex channel complementaries using Latent Class analysis. Latent classes have three useful properties: (i) they account for non-random selection of channels into campaigns, (ii) they capture pairwise and higher-order interactions between channels, and (iii) they allow for meaningful interpretation. We empirically describe the most common media channel archetypes and estimate their relationship to the effectiveness of a set advertising campaigns on a set of common brand-related performance metrics. We use a dataset of 1,083 advertising campaigns from around the world run between 2008 and 2019. We find that there is not a systematically “best” media mix that correlates to dominant performance across all metrics, but clear patterns emerge given specific metrics. We find that traditional channels (TV, outdoor) are commonly paired with digital channels (Facebook, YouTube) in high-performing campaigns. We also find that current marketing practice appears far from optimal, and simple strategies have the potential to increase brand mindset metric lifts by 50% or more.

BS SO18 - Small bowel intussusception after Roux-en-Y gastric bypass: A case report and review of literature

Abstract Background Small bowel obstruction after RYGB for obesity can occur due to various common causes like internal hernia and adhesions. One of the rare complications of RYGB is retrograde intussusception of jejunum at the common channel. Since it does not present with typical symptoms of small bowel obstruction, it is often challenging to consider it as differential diagnosis at initial presentation. Also, managing the intussusception at non bariatric centres could prove difficult due to location of it in the common channel, which will require understanding of orientation of alimentary and biliary limbs as well as reconstruction after resection of the intussusception. Method We collected the details of our patients admission episode from a different centre where she was admitted initially to understand the clinical behaviour of the condition. Also, we conducted a systematic search of literature databases like PubMed, Embase, CINAHL, ProQuest Dissertations & Theses using MeSH terms and keywords Intussusception, Retrograde intussusception, J-J intussusception, Intestinal Obstruction, Small bowel obstruction, Bowel obstruction, Obesity, Morbid obesity, Gastric Bypass, Roux-en-Y gastric bypass, Jejunojejunostomy, Jejuno-jejunostomy, Gastric by-pass, RYGB, Roux-en-Y. Data were extracted on to Excel sheet for analysis. Results The search yielded 41 case reports. Patients were operated in most instances except in seven cases where they had multiple episodes. The average age of presentation was 38 mostly in females and few instances being during pregnancy including our patient. Intussusception happened between 5 to 360 months after the initial operation with the average time after the operation being 66 months. Pain was the principal mode of presentation without classical symptoms of bowel obstruction. There were few instances of coffee ground vomiting. CT was the diagnostic modality in almost all cases. Recurrence was invariable when not managed with resection. Conclusion Small bowel intussusception after RYGB occurs retrogradely and does not present with classical symptoms and signs of small bowel obstruction. It can be reliably diagnosed with CT abdomen. Of note, medical management and no-resectional surgical management results in recurrence of this condition.

A Longer Biliopancreatic Limb and Shorter Common Channel Enhance Weight Loss But May Have Harmful Effects in Mouse Models of Roux-en-Y Gastric Bypass.

RYGB consists of the Roux limb (RL), the biliopancreatic limb (BPL), and the common channel (CC). There is no consensus on the optimal limb lengths. Using a mouse model of RYGB, 30 diet-induced obese mice were divided into two groups with varying BPL and CC lengths: a standard BPL with a long CC (RYGB S) and a long BPL with a short CC (RYGB L). Additionally, 9 age-matched, lean control mice (LC) were also included in this study. RYGB S had limb lengths of RL = 17%, BPL = 24%, and CC = 59%. RYGB L had limb lengths of RL = 17%, BPL = 32%, and CC = 51%. RYGB S and RYGB L had 67% and 40% survival, respectively. Mortality in RYGB L included more instances where the cause of death was not apparent. RYGB L demonstrated greater weight loss, lower energy expenditure, and lower heart mass as compared to RYGB S. Both RYGB groups had lower epidydimal fat mass, spleen mass, and bone mineral density compared to LC. RYGB L had a lower heart mass than RYGB S and LC. While the relative abundance of Eubacterium was lower in RYGB L than in RYGB S, no other gut microbiota differences were observed. A longer BPL with a shorter CC induces greater weight loss but may lead to adverse effects, including lower heart mass, reduced bone density, and deaths with unclear causes.

Africa Leadership Fellowship Antimicrobial Stewardship (ALF-A) – insights on mentorship experiences

Abstract Introduction As part of the second phase of the Commonwealth Partnership for Antimicrobial Stewardship (CwPAMS2) programme1, the Commonwealth Pharmacists Association is hosting the Africa Leadership Fellowship Antimicrobial Stewardship (ALF-A). This year-long, bespoke fellowship programme is designed to address identified gaps in antimicrobial stewardship (AMS) capabilities and strategies within the African context.2 ALF-A is funded by the UK Department of Health and Social Care's Fleming Fund and currently supports 45 early- to mid-career pharmacists in 8 sub-Saharan African countries: Ghana, Kenya, Malawi, Nigeria, Sierra Leone, Tanzania, Uganda and Zambia. Each fellow was assigned two mentors (in-country and UK-based) with expertise in health leadership, AMS, and/or OneHealth; mentors are responsible for supporting the assigned fellow for the year, focusing on role and leadership development, including the leading of an AMS improvement initiative project. Aim This study aims to evaluate the mentorship experience of CwPAMS2 ALF-A fellows. Methods An online survey was developed and disseminated to all 45 ALF-A fellows in May 2024. The survey was designed to gather information on demographic variables and general mentorship experience, both in-country and UK-based, including the perceived advantages and barriers associated with mentorship, and recommendations for improvement. Data were analysed in Excel using descriptive statistics, and the open-ended questions were thematically analysed using N-Vivo. No ethical approval was required for this study. Results A total of 40 fellows completed the survey (89% response rate). Just over half (55%) reported that they had no mentorship experience before ALF-A to support their professional development. The majority (93%) had at least one meeting with each of their ALF-A mentors; face-to-face meetings (48%) were the most common way of interacting with in-country mentors, and Zoom (45%) or MSTeams (43%) were the two most common communication channels with UK-based mentors. The perceived benefits of having a mentor were: professional growth, skill development and self-improvement; support in project direction; networking and connections. Some participants appreciated “knowledge sharing, especially from the UK mentor”. In contrast, challenges included: late mentorship assignment and start; misalignment of knowledge/expertise; logistical challenges (e.g. difficulties scheduling meetings due to busy schedules, lack of face-to-face meetings, internet connectivity issues); and personal challenges (e.g. overcoming shyness or other personal barriers to effective communication, uncertainty about what to discuss or how to initiate conversations with mentors). Time-difference/availability was also reported as a major challenge with the UK mentors. Discussion and conclusion This study revealed key insights into the mentorship experiences of ALF-A fellows, fostering professional growth and skill development. While early-career mentees highlighted the guidance provided and their increased confidence to deal with internal issues such as shyness and hesitancy, mid-career mentees further emphasised sustained career development and networking. Suggestions for improvement of the mentorship experience are currently being considered, including: improving/tailoring the matching process; providing additional training and support resources; improving engagement through flexible and accessible communication channels; and ensuring good time-management and flexibility. We continue to monitor and improve ALF-A as the programme progresses to better prepare pharmacists to take on leadership roles and contribute to AMS initiatives effectively.

Construction and Application of a Private 5G Standalone Medical Network in a Smart Health Environment: Exploratory Practice From China.

To date, the differentiated requirements for network performance in various health care service scenarios-within, outside, and between hospitals-remain a key challenge that restricts the development and implementation of digital medical services. This study aims to construct and implement a private 5G (the 5th generation mobile communication technology) standalone (SA) medical network in a smart health environment to meet the diverse needs of various medical services. Based on an analysis of network differentiation requirements in medical applications, the system architecture and functional positioning of the proposed private 5G SA medical network are designed and implemented. The system architecture includes the development of exclusive and preferential channels for medical use, as well as an ordinary user channel. A 3-layer network function architecture is designed, encompassing resource, control, and intelligent operation layers to facilitate management arrangements and provide network open services. Core technologies, including edge cloud collaboration; service awareness; and slicing of access, bearer, and core networks, are employed in the construction and application of the 5G SA network. The construction of the private 5G SA medical network primarily involves system architecture, standards, and security measures. The system, featuring exclusive, preferential, and common channels, supports a variety of medical applications. Relevant standards are adhered to in order to ensure the interaction and sharing of medical service information. Security is achieved through mechanisms such as authentication, abnormal behavior analysis, and dynamic access control. Three typical medical applications that rely on the 5G network in intrahospital, interhospital, and out-of-hospital scenarios-namely, mobile ward rounds, remote first aid, and remote ultrasound-were conducted. Testing of the 5G-enabled mobile ward rounds showed an average download rate of 790 Mbps and an average upload rate of 91 Mbps. Compared with 4G, the 5G network more effectively meets the diverse requirements of various business applications in prehospital emergency scenarios. For remote ultrasound, the average downlink rate of the 5G network is 4.82 Mbps, and the average uplink rate is 2 Mbps, with an average fluctuation of approximately 8 ms. The bandwidth, performance, and delay of the 5G SA network were also examined and confirmed to be effective. The proposed 5G SA medical network demonstrates strong performance in typical medical applications. Its construction and application could lead to the development of new medical service models and provide valuable references for the further advancement and implementation of 5G networks in other industries, both in China and globally.

Ion Channel Diseases as a Cause of Sudden Cardiac Death in Young People: Aspects of Their Diagnosis, Treatment, and Pathogenesis.

Sudden cardiac death (SCD) is the death of an apparently healthy person within one hour of the onset of symptoms, or within 24 hours of last being seen alive and well-with no evidence of an extra-cardiac cause. In autopsied cases, SCD is defined as the natural unexpected death of unknown or cardiac cause. The reported incidence figures for SCD vary widely. This review is based on clinical registry studies, meta-analyses, randomized controlled trials, systematic reviews, and current guidelines that were retrieved by a selective search in PubMed employing the key words "channelopathy," "Brugada syndrome," "long QT syndrome," "catecholaminergic polymorphic ventricular tachycardia," "short QT syndrome," and "early repolarization." Approximately 18% of cases of SCD in young persons are associated with cardiac channelopathy. The most common ion channel diseases affecting the heart are long QT syndrome and Brugada syndrome. The diagnosis is established by specific ECG abnormalities in the absence of structural heart disease. These can be unmasked by various maneuvers, e.g., the administration of sodium-channel blockers in Brugada syndrome. Imaging studies such as echocardiography, coronary angiography, and computed tomography are used to rule out structural heart disease and coronary artery disease. Long-term ECG and risk stratification scores can be useful aids to therapeutic decision-making. For some of these diseases, it is advisable for the patient to avoid particular triggers of ECG changes and cardiac arrhythmias in his or her everyday life. The near relatives of persons with congenital ion channel diseases should undergo clinical and genetic screening to protect them from SCD. The affected families should be investigated systematically so that appropriate diagnoses and treatments can be established.

Achieving a 35-Plex Tandem Mass Tag Reagent Set through Deuterium Incorporation.

Mass spectrometry-based sample multiplexing with isobaric tags permits the development of high-throughput and precise quantitative biological assays with proteome-wide coverage and minimal missing values. Here, we nearly doubled the multiplexing capability of the TMTpro reagent set to a 35-plex through the incorporation of one deuterium isotope into the reporter group. Substituting deuterium frequently results in suboptimal peak coelution, which can compromise the accuracy of reporter ion-based quantification. To counteract the deuterium effect on quantitation, we implemented a strategy that necessitated the segregation of nondeuterium and deuterium-containing channels into distinct subplexes during normalization procedures, with reassembly through a common bridge channel. This multiplexing strategy of "design independent sub-plexes but acquire together" (DISAT) was used to compare protein expression differences between human cell lines and in a cysteine-profiling (i.e., chemoproteomics) experiment to identify compounds binding to cysteine-113 of Pin1.

Long-term Outcome of the Dutch Common Channel Trial (DUCATI): Preservation of Superior Weight Loss Results Without Significant Malnutrition Side Effects.

The optimal bowel limb lengths for laparoscopic Roux-en-Y gastric bypass (LRYGB) to maximize weight loss while minimizing nutritional deficiencies in severe obesity treatment remain a topic of debate. The multi-center Dutch Common Channel Trial (DUCATI) aims to compare the outcomes of a very long Roux Limb Roux-en-Y gastric bypass (VLRL-LRYGB) with a standard Roux-en-Y gastric bypass (S-LRYGB). A total of 444 patients were randomly assigned in a 1:1, double-blind manner to undergo either VLRL-RYGB or S-LRYGB. Five-year follow-up data were assessed, concentrating on weight loss, obesity-related medical conditions, complications, re-operations, and malnutrition. Both groups had comparable total alimentary lengths (RL + CC). The VLRL-LRYGB group demonstrated significantly greater %TWL (32.2% vs. 28.6%, p = 0.002) and %EWL (81.2% vs. 70.3%, p = 0.002) at 5years. Eight (3.6%) patients in the VLRL-LRYGB group versus 2 (0.9%) in the S-LRYGB group (p = 0.055) needed modification surgery for malabsorption. Suboptimal clinical response rate was significantly higher (22.0% vs. 8.3%) in S-LRYGB group. No significant differences for nutrient deficiencies in favor of the S-LRYGB group were found. A 100-cm common channel with a relatively long Roux limb provides superior, sustainable weight loss over 5years, without significantly increased rate of malabsorption-related re-operations. These results suggest that a longer Roux limb can still ensure adequate micronutrient uptake in the total alimentary tract. These findings should be considered in discussions regarding the optimal Roux-en-Y limb length for severe obesity treatment.

Composite Functional and Quality of Life Outcomes in Adults Operated for Cloacal Malformation

IntroductionComposite long-term outcomes of cloacal malformations remain unclear. We aimed to evaluate bowel and bladder control, sexual function, reproductive health, and quality of life in adulthood. MethodsA Nordic multi-center cross-sectional observational study evaluating the outcome of adult patients with cloacal malformations was performed. Patient characteristics were retrieved from case records. Established questionnaires were sent to the patients to evaluate bowel- bladder- and sexual function and quality of life. ResultsThirty-four of 48 (70%) eligible patients with median age 28 years (18–45) responded. Eight (24%) patients had a common channel >3 cm. Imaging-confirmed spinal and sacral abnormalities were present in 4 and 17 patients respectively. 85% (n = 29/34, four patients with permanent urinary diversions after bladder neck closure excluded) reported no urinary leakage without physical activity or urge to urinate. Three patients had a permanent enterostomy. 42 % (n = 11/26) reported acceptable bowel function according to Bowel Function Score (with eventual ongoing bowel management). The median Profile of Female Sexual Function Score was below normative values. Quality of life was comparable to the reference population, but thirty percent scored within the distress domains. Eight patients (24%) had been pregnant (15 pregnancies), resulting in seven live births, but the need of assisted reproduction techniques (40%, n = 6/15) and miscarriage (40%, n = 6/15) was common. ConclusionsAdequate spontaneous bowel control was rare, while most patients were dry for urine without additional procedures. Cloacal malformation also have a negative impact on sexual function health related quality of life and reproductive health. Long-term follow-up is crucial, not only regarding bowel and bladder function, but also for sexual and reproductive function, which may be important negative factors for health-related quality of life. Level of EvidenceLevel IV.

The nexus of scam and fake news: An exploratory study of cases of fake news-scams in Singapore

The increasing prevalence of fake news as well as scams has been a cause for concern for authorities in Singapore in recent years. In particular, the concurrent rise in fake news and online scams has shown signs of convergence in the form of fake news-scams, where false information is manipulated and employed in scams. However, literature examining this emerging phenomenon is scarce. As such, this study aims to deepen our understanding of this novel issue by exploring how scammers employ fake news in terms of type, channels of transmission, and persuasion techniques. Drawing from local case studies ( n = 90) collected from 2016 to 2021, it was found that authority appeals were the most common theme employed in fake news-scams, and persuasion cues of authority were the most prevalent. In addition, Facebook was identified as the most common channel of transmission in the spread of fake news-scams. These findings serve to inform anti-scam prevention measures by local authorities and suggestions are made as to how various stakeholders (e.g. authorities, companies, and individuals) can be involved in dealing with fake news-scams.

Scattering of dark pions in Sp(4) gauge theory

Analyses of astrophysical data provide first hints on the self-interactions of dark matter at low energies. Lattice calculations of dark matter theories can be used to investigate them, especially in the case of strongly interacting dark matter. We consider Sp(4) gauge theory with two fundamental fermions as a candidate theory. We compute the scattering phase shift for the scattering of two identical dark pions and determine the parameters of the effective range expansion. Our exploratory results in the supposedly most common interaction channel provide a lower limit for the dark matter mass when compared to astrophysical data. We also provide first benchmarks of velocity-weighted cross sections in the relevant nonrelativistic domain. Published by the American Physical Society 2024

Priority-based band sharing for secondary users in cognitive radio networks

To improve wireless spectrum utilization, cognitive radio networks (CRNs) allow secondary users (SUs) opportunistic access to the frequency bands owned by primary users (PUs), when such PUs are inactive. A fully distributed CRN architecture is quite favorable, as it does not require any centralized scheduling, nor does it require coordination between SUs via a common control channel. This can reduce cost and avoid single point-of-failure issues. However, uncoordinated access to the spectrum by competing SUs, if not done judiciously, can cause excessive collisions and limit performance, which can be detrimental to the usefulness of CRNs, especially if some SUs have urgent traffic to send. Hence, we present a novel protocol to support traffic with multiple classes of priority within a fully distributed CRN. In such protocol, competing SUs attempt to access the spectrum autonomously, but rationally, based on their priority level, opting to transmit their packets when it is beneficial to both the SU itself and also to the overall system performance. Simulations confirm that the proposed protocol achieves excellent overall network performance, while ensuring that higher priority packets experience higher throughput and smaller delay compared to lower priority packets.

Does the length of bypassed bowel during distal gastric bypass affect weight loss?

Weight recurrence (WR) affects > 20% of patients following Roux-en-Y gastric bypass (RYGB). Shortening of the common channel (CC) after RYGB (distal bypass) has been proposed for additional weight loss in patients with WR, but results vary, and concerns for vitamin deficiencies/malnutrition exist. Our aim was to determine whether the percentage of bowel bypassed after distal bypass is associated with the amount of postoperative weight loss. Patients undergoing distal bypass between 2018 and 2022 were reviewed. Small bowel limb lengths before and after distal bypass were measured, and the percentage of bypassed bowel was calculated (= bypassed biliopancreatic limb/total small bowel length). Patients were dichotomized into two groups based on the percentage bypassed bowel (≤ 50% vs. > 50%). Weight loss (measured as excess BMI loss; EBIL%), comorbidities resolution, complications, and nutritional deficiencies were reviewed. Thirty female patients underwent distal bypass during the study period. After distal bypass, the Roux was lengthened to 150cm (75-175cm) from 75cm (20-200cm), and the CC shortened to 150cm (100-310cm) from 510cm (250-1000cm). These changes resulted in an increase in the size of the bypassed biliopancreatic limb from 40cm (15-90cm) to 330cm (180-765cm) and a total alimentary limb (TALL; Roux + CC) shortening from 590cm (400-1075cm) to 300cm (250-400cm). The group with > 50% bowel bypassed had higher EBIL%. Overall EBIL% was 36.9 ± 14.7%, 53.3 ± 25.6%, and 62.1 ± 36.9% at 0.5, 1, and 2years, respectively. There were minimal vitamin deficiencies. Diabetes resolved in 100% (n = 3/3), HTN in 67% (n = 10/15), and GERD in 73% (n = 11/15). Complication rate was 23%. No reintervention for malnutrition or vitamin deficiencies was required. Distal bypass effectively leads to considerable weight loss and comorbidity improvement in patients with WR after RYGB, but the amount of weight loss depends on the percentage of bypassed bowel. An exact threshold of bypassed bowel that optimizes weight loss outcomes and simultaneously minimizes the nutritional complications needs to be determined. Meanwhile, close monitoring for vitamin deficiencies is recommended.

ThP3.10 - Initial experience with laparoscopic single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) in Class IV (BMI 50-60kg/m2) and Class V (BMI > 60 kg/m2) Obesity

Abstract Aims Single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) is a simplification of the duodenal switch (DS) in which alimentary limb is eliminated, and common channel is lengthened from 200 to 300 cm is gaining recognition as effective procedure in Class IV (BMI 50-60 kg/m2) and Class V (BMI >60 kg/m2) obesity. The aim of study is to discuss the surgical technique and analyse initial outcomes after introduction of SADI-S in our department for management of Class IV and Class V Obesity. Methods This is a retrospective cohort study of consecutive patients who underwent SADI-S at a tertiary level teaching hospital in NHS. Only patients who underwent single stage SADI-S procedure with minimal follow-up of 30 days were included in study. Patients who underwent Sleeve gastrectomy first, followed by duodenal switch in second stage as part of two-stage strategy were excluded. Results Total 14 patients, 2 (14.2%) males and 12 (85.8%) females were included in study. The median pre-op BMI was 56.1 (51.95-69) kg/M2 and median Pre-op weight was 149.2 (121.8 – 163.2) kg. 9 pts had diabetes, 11 pts OSA on CPAP, 8 pts HTN, 6 pts fibromyalgia etc. 1 patient had sleeve staple-line bleed which was managed conservatively with fluids and blood transfusion. No re-operations, mortality or re-admissions were recorded. Median length of stay was 2 days. Conclusion SADI-S is a promising surgery in Class IV and Class V obesity patients with low postoperative morbidity. The postoperative recovery and protocol is similar to standard procedure like sleeve gastrectomy and Roux-Y-gastric bypass.

A magnetically switchable demultiplexer via Terfenol-D in phononic crystal

This study introduces a novel approach for developing a controllable demultiplexer by applying a magnetic field to Terfenol-D cylinders within a solid–solid phononic crystal structure. Dynamic controllable demultiplexers are essential devices in acoustic and optical communication networks, yet adjustable elastic demultiplexers are notably lacking in current sound systems and acoustic communication technologies. The proposed phononic crystal-based demultiplexer features a square lattice (12 × 19) composed of tungsten cylinders embedded in a poly methyl methacrylate (PMMA) substrate. The switchable design consists of two identical, symmetrical parts separated by an input waveguide. In addition, each unit includes an output channel, a common input channel, and a square ring resonator, with the output channel side-coupled to the input bus waveguide. Moreover, Terfenol-D, a magnetostrictive material, is utilized in the hollow cylinders of the output channels. Switchability of the elastic demultiplexer outputs is achieved by dynamically altering the Young’s modulus of the Terfenol-D cylinders through the application of a magnetic field. This magnetic influence modifies the Young’s modulus of the Terfenol-D material in the output waveguides, enabling controllability. By varying the magnetic field applied to the demultiplexer, we find two distinct values of Young’s modulus within the structure. These two values facilitate the high transmission of two desirable peaks with narrow bandwidth through the output channels, allowing for switchable functionality based on the magnetic field’s position. The proposed demultiplexer demonstrates an average crosstalk value of −25.34 dB, indicating strong performance, along with a high average quality factor (Q) of 1773.5 and low average insertion losses of 0.85 dB in the MHz frequency range. The solid–solid elastic controllable demultiplexer is simulated using the finite element method, showcasing its potential for practical applications.

Tandem MS Elucidation of the Late-Stage Degradation Mechanism of Nitroplasticizer.

Understanding the degradation behavior of nitroplasticizer (NP) and the subsequent production of nitro-organics is crucial for both environmental monitoring and material development. A nontargeted approach via LC-QTOF-MS was employed to thoroughly study the degradation mechanism of NP in its late aging stage. Both positive and negative modes of ESI were performed to increase the compound coverage. To shed light on the fragmentation behavior of NP degradants (e.g., compounds containing a high density of NO2 moieties and oxygen sites) in the positive mode, which is rarely reported, the high-resolution tandem MS information on precursor ions at m/z 251(+), 254(+), 266(+), and 270(+) and a pair of isomeric ions at m/z 284(+) was investigated to extract their common diagnostic ions and dissociation channels, including the neutral loss of 2,2-dinitropropanol, nitro-nitrite rearrangement, homolytic cleavage of NO2, and simple inductive cleavage. Additionally, leveraging the sensitivity for nitroaromatics in the negative polarity, negative ions m/z 182(-) and 233(-) are identified as dinitroaniline and dinitronaphthol, respectively, which confirm the secondary hydrolysis pathway of the antioxidant (e.g., N-phenyl-2-naphthylamine) postulated in our previous work. In addition to earlier findings, the detection of these eight degradants further supports the evidence of increased acid concentration and aging temperatures in the late-stage NP environment, which contribute to intricate degradation behaviors in different aging environments.

Flow boiling heat transfer enhancement of R134a in additively manufactured minichannels with microengineered surfaces

Additive manufacturing (AM) of metal components has opened new frontiers in heat transfer applications owing to its wide design freedom, which enables previously unexplored geometries with enhanced thermal performance to be developed. Open minichannels, on the other hand, consist of an extra manifold situated above the common flow channels, have been demonstrated to effectively reduce pressure drop and two-phase flow instability by mitigating backflow and maldistribution. In this paper, we synergized open minichannel design methodology with an ultrascalable surface microstructuring method for AM AlSi10Mg to improve flow boiling heat transfer performance of R134a. Experiments were conducted at the refrigerant mass flow rates (ṁ) of 0.005 kg/s to 0.01 kg/s (corresponding to mass fluxes of 73 to 146 kg/m2⋅s), and effective heat fluxes (qeff) of 1.8 kW/m2 to 141 kW/m2, by supplying 2 ℃ subcooled liquid to the minichannel inlet at saturation pressure (Psat) of 7.27 bar. The effects of heat flux, nucleation site density, mass flow rate and location of nucleation sites on the harmonic-average heat transfer coefficient (have) and pressure drop (ΔP) along the flow direction are investigated and compared against a conventionally manufactured (Al6061) counterpart. Our results show that the proposed etching process significantly improves the cooling performance of AM microstrucured minichannels, resulting in 210% higher have than Al6061 with negligible pressure drop penalty. The flow visualization results reveal a sequential order of nucleation site activation with increasing heat flux for microstructured open minichannels, which starts from the top of fins, followed by the corners and other three surfaces within the channels. This also results in the non-negligible effects of mass flow rate on cooling performance for microstructured minichannels, with approximately 10%–66% higher have at the lowest mass flow rate. Besides, the pressure drop penalty resulting from plain AM rough surface is also reduced by up to 13% through the proposed microstructuring process. In all, this work not only successfully identifies the dominant mechanisms in AM microstructured open minichannels, but it also provides useful minichannel design guidelines for high-performance two-phase cooling devices by AM.

(Invited) Shunt-currents in Alkaline Water-Electrolyzers and Renewable Energy

Shunt-currents in bipolar cell stack design with a common electrolyte-feed and -outlet is an inevitable physical phenomenon governed by Ohms law that causes some extra challenges when alkaline water-electrolysers shall operate on renewable energy that is both dynamic and intermittent. Shunt-currents are also referred to as bypass-current or creep-current. The shunt-currents are to much degree governed by the electrolyte inside the cell stack manifold system that transports lye in and out of the cells. The electrolyte inside the manifold system also electrically connects the individual cells together and enables transport of ions/electricity in parallel to the cell stack. Thus, a small portion of the rectifier current is being shunted outside the cells and does not contribute to any production. Previous work on shunt-current modelling brought new insight on how to design the manifolds and raised the awareness on shunt-current and the use of metallic manifolds which both reduced the ohmic resistivity of the manifold system and was a source of secondary electrolysis.Classic alkaline water-electrolysers are typically using an internal manifold system where the inlet ports are located at the bottom of the cell stack and the outlet ports are located at the top, and where the ports connecting the cell-interior and the common manifold channel are short and straight. Such design has in the past worked satisfactory for alkaline water-electrolysers that have been working on a high nominal load and only being shut-down for maintenance a few times over the stack-lifetime, mainly causing a modest reduction in the current efficiency. Membrane-chlorine electrolysers on the other hand, are designed for very small shunt-currents by using an external manifold system, which enables a current protection system that protects electrodes from corrosion under shutdown conditions.Shunt-currents bypassing the cell stack does not contribute to any product and therefore constitutes a loss in current efficiency and, hence, an accordingly loss in the energy efficiency (the shunt-currents still adds to the electricity bill). The atmospheric alkaline electrolyser has a modest loss in current efficiency at nominal load where the high gas volume blocks much of the current path in the rather open outlet ports. The high-pressure alkaline electrolysers on the other hand, where the gas volumes are much smaller, the current efficiency can be as low as 89% at nominal load due to shunt-currents when using simple internal manifold system. For an electrolyser with already low current efficiency at the nominal load, the current efficiency will drop dramatically as the electrolyser is taken to lower load, severely compromising the energy efficiency. The impact on shunt-currents also dramatically increases for increased number of cells in a cell stack, and eventually limits the number of cells that can be assembled in one single cell stack operating on the same common lye system.Shutdown and discharge of the electrodes may further lead to corrosion and degradation of the electrodes, strongly influenced by the shunt-currents and the manifold system. Large cell stacks will discharge faster and deeper, eventually causing corrosion of the electrodes. As the cell stack is discharged the current in the cell stack is reversed where the hydrogen electrode is being polarized to anodic potentials, and the oxygen electrode is polarized to low cathodic potentials which eventually may challenging the material stability. Thus, evaluation of electrode potentials must be an integral part of development of industrial electrodes [LeRoy] and especially in intermittent operation where frequent shutdown will occur. A good integration of the manifold system into the cell stack can potentially mitigate both the loss of current efficiency under dynamic operation and the electrode corrosion under intermittent operation.

Intracorporeal anastomosis in minimally invasive right hemicolectomy: a nationwide survey of the Korean Society of Coloproctology.

We investigated the current practices and perceptions of colorectal surgeons in South Korea regarding intracorporeal ileocolic anastomosis (IIA) in minimally invasive right hemicolectomy (RHC). Members of the Korean Society of Coloproctology (KSCP) participated in an online survey encompassing demographic information, surgical experiences, methods for IIA, and advantages, barriers, and perceptions of IIA. We performed a statistical analysis of survey results. Among the 1,074 KSCP members contacted, 178 responded to the survey. Most respondents were males aged 40-49 years with >10 years of experience who were affiliated with a tertiary healthcare facility. One hundred fifty-six respondents had performed <100 colorectal cancer surgeries annually. Fifty-nine respondents reported experiences of the IIA technique in minimally invasive RHC. Most respondents favored the isoperistaltic side-to-side (S-S) anastomosis and stapled S-S anastomosis, hand-sewn closure for the common channel, and the periumbilical area for primary specimen extraction. Respondents with IIA experience emphasized the reduction in postoperative complications as the primary reason for performing IIA, whereas respondents without IIA experience cited the lack of benefits as the main deterrent. Respondents commonly cited concerns regarding anastomotic leakage and intraabdominal contamination as the primary reasons for not performing IIA. Respondents with IIA experience demonstrated a more positive response towards attempting or transitioning to IIA than those without. Respondents with IIA experience prioritized self-sufficiency, whereas respondents without IIA experience prioritized proctorship and discussions of the initial cases. Measures to standardize the IIA technique and appropriate training programs must be implemented to enhance its use in minimally invasive RHC.

Cross-layer Design Based Common Data Channel Selection Scheme in Cognitive Radio Ad-hoc Network

Cross-layer Design Based Common Data Channel Selection Scheme in Cognitive Radio Ad-hoc Network