bluuebunny/crossref_metadata_2025 huggingface dataset:
The Influence of the Superficial Venous System on DIEP Flap Drainage in Breast Reconstruction
Authors: Choi Esther Mihwa Oh , Ribeiro Renan Diego Américo , Montag Eduardo , Ueda Thiago , Okada Alberto Yoshikazu , Munhoz Alexandre Mendonça , Busnardo Fabio de Freitas , Gemperli Rolf
Published: September 2023

Background Autologous tissue has become the gold standard in breast reconstruction. The use of a deep inferior epigastric perforator (DIEP) flap has the advantages of giving a natural appearance to the reconstructed breast and being associated with lower morbidity at the donor site when compared with the transverse rectus abdominis myocutaneous flap. Venous complications such as venous thrombosis and insufficiency remain the main causes of flap loss and surgical revisions. The aim of this study was to evaluate the influence of superficial venous drainage of the DIEP flap and the addition of a second venous anastomosis have on flap survival.

Methods This was a retrospective cohort study collected from a prospective database maintained by our institution. Data was obtained from the medical records of female patients who underwent mastectomy and breast reconstruction with a DIEP flap between March 2010 and March 2017. We evaluated 137 DIEP patients with unilateral breast reconstructions. In 64 (46.7%) the deep venous system was chosen and 73 (53.3%) had an additional superficial vein anastomosed.

Results Out of the 137 patients evaluated, there were 16 (11.67%) cases of revision, 14 (10.21%) were due to venous thrombosis. Twelve cases (8.75%) of flap loss were reported. Reoperation rate was lower in the dual venous drainage group when compared with the single venous drainage group (p = 0.005), as was the rate of flap loss (p = 0.006) and reoperation due to venous thrombosis (p = 0.002). Out of the 125 DIEP flaps, fat necrosis was clinically identified in 7 (5.1%) cases, and the rate was lower in the dual venous drainage system group (p = 0.01).

Conclusion Dual venous drainage of a DIEP flap appears to reduce the rates of venous thrombosis, reoperation, total flap loss, and fat necrosis.
Implications of Single-Vessel Runoff on Long-Term Outcomes of Free Tissue Transfer for Lower Extremity Reconstruction
Authors: Huffman Samuel S. , Bovill John D. , Li Karen , Spoer Daisy L. , Berger Lauren E. , Bekeny Jenna C. , Akbari Cameron M. , Fan Kenneth L. , Evans Karen K.
Published: September 2023

Background Patients with complex lower extremity (LE) wounds and single-vessel LE runoff (1-VRO) are often considered for amputation. While more challenging, free tissue transfer (FTT) is a means for limb salvage. This study aims to demonstrate the feasibility of limb salvage with FTT in patients with 1-VRO.

Methods Patients undergoing FTT by a single surgeon between 2011 and 2021 were retrospectively reviewed. Data collected included demographics, wound characteristics, vascular status, and operative details. Patients were divided into cohorts based on 1- versus 3-VRO of tibial vessel inflow. Outcomes of interest included postoperative complications such as flap necrosis, flap success, limb salvage, and ambulatory status.

Results A total of 188 patients underwent FTT to LE, with 25 patients (13.3%) having 1-VRO. Patients with 1-VRO had a comparable prevalence of diabetes (56.0% vs. 50.0%, p = 0.569) and end-stage renal disease (8.0% vs. 3.7%, p = 0.319). Osteomyelitis was more common in the 1-VRO group (80.0% vs. 60.1%, p = 0.056). FTT donor sites and flap composition were similar between cohorts. At mean follow-up of 21.2 months (interquartile range 24.5:5.6, 30.1 months), limb salvage rates were similar between cohorts (84.0% vs. 91.4%, p = 0.241), with no significant differences in ambulatory status or mortality. Higher complication rates occurred in the 1-VRO cohort (48.0% vs. 21.5%, p = 0.004), of which partial flap necrosis was more prevalent in the 1-VRO group (8.0% vs. 1.2%, p = 0.029). There was no difference in flap success rates between groups (p = 0.805). More postflap angiograms were performed in the 1-VRO group (32.0% vs. 9.2%, p = 0.001), but there was no difference in need for repeat percutaneous endovascular intervention between groups.

Conclusion This study demonstrates that FTT reconstruction to the LE remains a reliable reconstruction option for limb salvage in patients with single-vessel supply to the LE. Reliance on advanced perioperative management and patient optimization is effective at reducing negative outcomes.
Lymphovenous Coupler-Assisted Bypass for Immediate Lymphatic Reconstruction
Authors: Spoer Daisy L. , Berger Lauren E. , Towfighi Parhom N. , Deldar Romina , Gupta Nisha , Huffman Samuel S. , Sharif-Askary Banafsheh , Fan Kenneth L. , Parikh Rajiv P. , Tom Laura K.
Published: September 2023

Background Breast cancer-related lymphedema is the most common cause of lymphedema in the United States and occurs in up to 50% of individuals receiving axillary lymph node dissection (ALND). Lymphovenous bypass (LVB) at the time of ALND may prevent lymphedema, but long-term results and anastomotic patency are unclear. This study evaluates the feasibility and outcomes of performing immediate lymphatic reconstruction via coupler-assisted bypass (CAB).

Methods This is a retrospective review of all patients undergoing prophylactic LVB following ALND at two tertiary care centers between 2018 and 2022. Patients were divided into cohorts based on whether they received the “standard” end-to-end (E-E) suturing or CAB technique. The primary outcome of interest was development of lymphedema. Quantitative and qualitative assessments for lymphedema were performed preoperatively and at 3, 6, 12, and 24 months postoperatively.

Results Overall, 63 LVBs were performed, of which 24 lymphatics underwent immediate reconstruction via “CAB” and 39 lymphatics via “standard” end-to-end suture. Patient characteristics, including body mass index, and treatment characteristics, including radiation therapy, did not significantly differ between groups. CAB was associated with a greater mean number of lymphatics bypassed per vein (standard 1.7 vs. CAB 2.6, p = 0.0001) and bypass to larger veins (standard 1.2 vs. CAB 2.2 mm, p < 0.0001). At a median follow-up of 14.7 months, 9.1% (1/11) of individuals receiving CAB developed lymphedema. These rates were similar to those seen following standard bypass at 4.8% (1/21), although within a significantly shorter follow-up duration (standard 7.8 vs. CAB 14.7 months, p = 0.0170).

Conclusion The CAB technique is a viable, effective technical alternative to the standard LVB technique. This comparative study of techniques in prophylactic LVB suggests that CABs maintain long-term patency, possibly due to the ease of anastomosing several lymphatics to single large caliber veins while reducing the technical demands of the procedure.
Nonabsorbable Barbed Sutures for Diastasis Recti. A Useful Device with Unexpected Risk: Two Case Reports
Authors: Giorgi Lorenzo , Ponti Veronica , Boriani Filippo , Margara Andrea
Published: September 2023

The introduction of nonabsorbable barbed sutures in plastic surgery has allowed the achievement of significant results in terms of efficacy and short- and long-term outcomes. However, a nonabsorbable material with no antibacterial coating could act as a substrate for subclinical bacterial colonization and thereby determine recurrent subacute and chronic infective–inflammatory processes. The authors report a clinical experience of subacute infectious complications after two cases of diastasis recti surgical correction. The authors present a two-case series in which a nonabsorbable barbed suture was used for the repair of diastasis recti. The postoperative course was complicated by surgical site infection. The origin of the infectious process was clearly localized in the fascial suture used for diastasis correction. The suture was colonized by bacteria resulting in the formation of multiple granulomas of the abdominal wall a few months postoperatively. In both the reported cases, the patients partially responded to the antibiotic targeted therapy and reoperation was required. The microbiological analyses confirmed the colonization of sutures by Staphylococcus aureus. Barbed nonabsorbable sutures should be avoided for diastasis recti surgical correction to minimize the risk of infectious suture-related complications. The paper's main novel aspect is that this is the first clinical report describing infectious complications after surgical correction of diastasis recti with barbed polypropylene sutures. The risk of microbiological subclinical colonization of polypropylene suture untreated with antibacterial coating, therefore, should be taken into account.
Total Synthesis of Marine Macrolide Natural Products by the Macrocyclization/Transannular Pyran Cyclization Strategy
Authors: Fuwa Haruhiko
Published: September 2023

In this Account, we summarize the development of a new strategy for streamlined synthesis of tetrahydropyran-embedded macrolactones and its successful implementation to a 13-step synthesis of (–)-exiguolide and an 11-step synthesis of (+)-neopeltolide.

1 Introduction

2 Development of Macrocyclization/Transannular Pyran Cyclization Strategy

3 Total Synthesis of (–)-Exiguolide

4 Total Synthesis of (+)-Neopeltolide

5 Conclusions
Cryoanalgesia: Review with Respect to Peripheral Nerve
Authors: Slavin Benjamin R. , Markowitz Moses I. , Klifto Kevin M. , Prologo Frank J. , Taghioff Susan M. , Dellon A. Lee
Published: September 2023

Background Cryoanalgesia is a tool being used by interventional radiology to treat chronic pain. Within a certain cold temperature range, peripheral nerve function is interrupted and recovers, without neuroma formation. Cryoanalgesia has most often been applied to the intercostal nerve. Cryoanalgesia has applications to peripheral nerve surgery, yet is poorly understood by reconstructive microsurgeons.

Methods Histopathology of nerve injury was reviewed to understand cold applied to peripheral nerve. Literature review was performed utilizing the PubMed and MEDLINE databases to identify comparative studies of the efficacy of intraoperative cryoanalgesia versus thoracic epidural anesthesia following thoracotomy. Data were analyzed using Fisher's exact and analysis of variance tests. A similar approach was used for pudendal cryoanalgesia.

Results Application of inclusion and exclusion criteria resulted in 16 comparative clinical studies of intercostal nerve for this review. For thoracotomy, nine studies compared cryoanalgesia with pharmaceutical analgesia, with seven demonstrating significant reduction in postoperative opioid use or postoperative acute pain scores. In these nine studies, there was no association between the number of nerves treated and the reduction in acute postoperative pain. One study compared cryoanalgesia with local anesthetic and demonstrated a significant reduction in acute pain with cryoanalgesia. Three studies compared cryoanalgesia with epidural analgesia and demonstrated no significant difference in postoperative pain or postoperative opioid use. Interventional radiology targets pudendal nerves using computed tomography imaging with positive outcomes for the patient with pain of pudendal nerve origin.

Conclusion Cryoanalgesia is a term used for the treatment of peripheral nerve problems that would benefit from a proverbial reset of peripheral nerve function. It does not ablate the nerve. Intraoperative cryoanalgesia to intercostal nerves is a safe and effective means of postoperative analgesia following thoracotomy. For pudendal nerve injury, where an intrapelvic surgical approach may be difficult, cryoanalgesia may provide sufficient clinical relief, thereby preserving pudendal nerve function.
The Impact of Timing of Delayed Autologous Breast Reconstruction following Postmastectomy Radiation Therapy on Postoperative Morbidity
Authors: Mirza Humza N. , Berlin Nicholas L. , Sugg Kristoffer B. , Chen Jung-Shen , Chung Kevin C. , Momoh Adeyiza O.
Published: September 2023

Background The ideal time to perform reconstruction after the completion of postmastectomy radiation therapy (PMRT) in patients with locally advanced breast cancer is currently unknown. We evaluate the association between the timing of delayed autologous breast reconstruction following PMRT and postoperative complications.

Methods Patients who underwent mastectomy, PMRT, and then delayed autologous breast reconstruction from 2009 to 2016 were identified from the Truven Health MarketScan Research Databases. Timing of reconstruction following PMRT was grouped 0–3, 3–6, 6–12, 12–24, and after 24 months. Multivariable models were used to assess associations between timing of reconstruction following PMRT and key measures of morbidity.

Results A total of 1,039 patients met inclusion criteria. The rate of any complications for the analytic cohort was 39.4%, including 13.3% of patients who experienced wound complications and 11.3% of patients requiring additional flaps. Unadjusted rates of complications increased from 23.4% between 0 and 3 months to 49.4% between 3 and 6 months and decreased thereafter. Need for additional flaps was highest within 3 to 6 months (14.0%). Multivariate analysis revealed higher rates of any complications when reconstruction was performed between 3 and 6 months (odds ratio [OR]: 3.04, p < 0.001), 6 and 12 months (OR: 2.66, p < 0.001), or 12 and 24 months (OR: 2.13, p = 0.001) after PMRT. No difference in complications were noted in reconstructions performed after 24 months compared with those performed before 3 months (p > 0.05). However, rates of wound complications were least likely in reconstructions after 24 months (OR: 0.34, p = 0.035).

Conclusion These findings suggest plastic surgeons may consider performing autologous breast reconstruction early for select patients, before 3 months following PMRT without increasing postoperative morbidity.
Oxidative Cyclization Reactions Catalyzed by Designed Transition-Metal Complexes: A New Strategy for the Synthesis of Flavone, Quinolone, and Benzofuran Derivatives
Authors: Ghosh Kaushik , Ahmed Naseem , Singh Apurva , Singh Sain
Published: September 2023

An efficient and convenient synthetic protocol is reported for the synthesis of 2-phenyl-4H-chromen-4-one, 2-phenylquinolin-4(1H)-one, and 11H-benzofuro[3,2-b]chromen-11-one derivatives from 2′-hydroxychalcones, 2′-aminochalcones, and 3-hydroxyflavones, respectively, using transition-metal catalysts and TEMPO as an oxidizing agent. This catalytic heterocyclization approach involves in situ free-radical generation as phenoxyl radicals were detected by EPR spectroscopic study and H2O2 was formed. The present method has numerous advantages, such as high atom-economy, less hazardous synthesis, benign solvent and auxiliaries, easy handling, and broader substrate scope with good to excellent product yields.
Three-Dimensional Volumetric Investigation of Onodi Cells: A Multi-Slice Computed Tomography Study
Authors: Dieguez Flavia Limberg , Rosa Catharina Simioni De , Braz-Silva Paulo Henrique , Lopes Sergio Lucio Pereira de Castro , Costa Andre Luiz Ferreira
Published: September 2023

Introduction Onodi cells (OCs) are posterior ethmoid cells that are located above the sphenoid sinus, close to or even surrounding the carotid artery and optic nerve.

Objective To investigate and evaluate the volumetric variation of OCs through multi-slice computed tomography (MSCT) scans.

Methods We performed a retrospective review of MSCT scans of 79 subjects, 40 male and 39 female patients, Whose age ranged from 18 to 83 (mean: 39.6) years. The volumes of the OCs on the right and left sides were measured using the ITK-SNAP software (open-source) with semiautomatic segmentation. The possible relationships involving age, gender, contact with the optic nerve, extension of the pneumatization of the posterior ethmoid cells into the clinoid processes, mucous thickening in the anterior and posterior ethmoid cells, and obliteration of the sphenoethmoidal complex were analyzed with the Pearson correlation and Chi-squared tests according to the type of data compared and logistic regression models (p < 0.05).

Results We observed that an increase of one unit in the volume of OCs also increases the chance of extension of pneumatization into the clinoid processes by 0.15% (p = 0.001). No significant correlations were identified regarding age, gender, and volume of the OCs.

Conclusion The volume of the OCs has effects on the extension of pneumatization into the clinoid processes.
Wound Coverage in Extensive Necrotizing Fasciitis with Chronic Liver Disease
Authors: Choundappan M.
Published: September 2023

Chronic liver disease is characterized by lowered immunity, altered hematological parameters, and poor wound healing. Surgeons may hesitate to intervene in such patients when they present with necrotizing fasciitis (NF) or misinform the patients regarding their chances of survival. This is because of the poor nutritional state, thrombocytopaenia, and abnormal coagulation profile. However, recent guidelines show that platelet count and prothrombin time/international normalized ratio (PT-INR) do not predict postoperative bleeding. We can proceed with debridement followed by skin grafting of wounds in such patients. This will help reduce the high mortality rate of NF in cirrhotic patients.
Interosseus Membrane Reconstruction Following a Forearm Injury: A Case Report
Authors: Shine S.J. , Bamberger H.B. , Spieser C.E. , Sferrella A.M.
Published: September 2023

Background Essex-Lopresti injuries are complex, frequently missed forearm/elbow injuries consisting of a fracture of the radial head with disruption of both the distal radioulnar joint (DRUJ) and the interosseous membrane (IOM). Ideal management of these injuries remains controversial, especially in relation to the IOM, due in part to underdiagnosis of IOM injury and incomplete understanding of the IOM role.

Methods A 43-year-old man sustained an open radial shaft fracture with associated radial head subluxation, coronoid base fracture, and DRUJ injury with ulnar head subluxation. He was taken for surgery, where elbow instability with near complete disruption of the IOM was observed. Persistent gross rotational instability was noted following radius fixation, so braided suture and button reconstruction of the central band of the IOM was performed. This restored rotational and longitudinal stability to the radiocapitellar joint and DRUJ. Over 1 year out from the index surgery, the patient's elbow and DRUJ have remained stable, and he is back working as a laborer.

Results While little literature exists on outcomes of acute IOM reconstruction in these injuries, recent biomechanical studies have shown the importance of the central band on rotational elbow stability.

Conclusion This case supports the importance of the central band of the IOM by demonstrating the impact of its repair on the longitudinal and rotational stability of the elbow and DRUJ. IOM repair has the potential to improve our treatment of this complicated injury by better restoring forearm stability and function of the elbow, which future studies could help further elucidate.
The Effect of Working Length, Fracture, and Screw Configuration on Plate Strain in a 3.5-mm LCP Bone Model of Comminuted Fractures
Authors: Wainberg S.H. , Moens N.M.M. , Ouyang Z. , Runciman J.
Published: September 2023

Introduction This study provides a comprehensive examination of plate strain under realistic fracture configurations. The effect of plate working length, plate contact, fracture length, and position on strain was evaluated using bone surrogates subjected to “load-controlled,” nondestructive conditions.

Materials and Methods Five 3.5-mm locking compression plates (LCP) were instrumented with six strain gauges. The gauges were glued between holes in predetermined locations marked by laser engraving. Nine fracture models were created using bone surrogate, each representing a combination of the criteria under study: long versus short working length, degree of plate compression, fracture location, and fracture length. All five plates were tested under each of the nine configurations. The constructs were mounted in an Instron testing machine with a 5-kN load cell. Each specimen was cyclically loaded at a rate of 5 mm/min to 50, 100, and 200 N.

Results Decreased plate strain was noted with a short plate working length in all fracture configurations (p < 0.05). Increasing the plate working length increased the strain at higher loads and on the plate adjacent to the fracture gap. The size of the fracture gap and fracture location had minimal effects on plate strain (p < 0.05). Elevation of the plate off the bone (1.5 mm) resulted in increased plate strain under all loading conditions (p < 0.05).

Conclusion Our null hypothesis was rejected in that a short plate working length resulted in decreased plate strain in all comminuted fracture configurations. Our secondary hypothesis was validated in that elevation of the plate from the bone resulted in increased strain in all configurations. As plate strain identifies regions of mechanical weakness whereby a construct may prematurely fail by acute overload or cyclic fatigue, identifying factors that may increase plate strain allows the surgeon to reduce these variables as much as possible to reduce the incidence of implant failure and subsequent fracture failure.
More than just an eagle killer: The freshwater cyanobacterium
Aetokthonos hydrillicola
produces highly toxic dolastatin derivatives
Authors: Schwark Markus , Martínez Yerena José A. , Röhrborn Kristin , Hrouzek Pavel , Divoká Petra , Štenclová Lenka , Delawská Kateřina , Enke Heike , Vorreiter Christopher , Wiley Faith , Sippl Wolfgang , Sobotka Roman , Saha Subhasish , Wilde Susan B. , Mareš Jan , Niedermeyer Timo H. J.
Published: September 2023

Cyanobacteria are infamous producers of toxins. While the toxic potential of planktonic cyanobacterial blooms is well documented, the ecosystem level effects of toxigenic benthic and epiphytic cyanobacteria are an understudied threat. The freshwater epiphytic cyanobacterium
Aetokthonos hydrillicola
has recently been shown to produce the “eagle killer” neurotoxin aetokthonotoxin (AETX) causing the fatal neurological disease vacuolar myelinopathy. The disease affects a wide array of wildlife in the southeastern United States, most notably waterfowl and birds of prey, including the bald eagle. In an assay for cytotoxicity, we found the crude extract of the cyanobacterium to be much more potent than pure AETX, prompting further investigation. Here, we describe the isolation and structure elucidation of the aetokthonostatins (AESTs), linear peptides belonging to the dolastatin compound family, featuring a unique modification of the C-terminal phenylalanine-derived moiety. Using immunofluorescence microscopy and molecular modeling, we confirmed that AEST potently impacts microtubule dynamics and can bind to tubulin in a similar matter as dolastatin 10. We also show that AEST inhibits reproduction of the nematode
Caenorhabditis elegans
. Bioinformatic analysis revealed the AEST biosynthetic gene cluster encoding a nonribosomal peptide synthetase/polyketide synthase accompanied by a unique tailoring machinery. The biosynthetic activity of a specific N-terminal methyltransferase was confirmed by in vitro biochemical studies, establishing a mechanistic link between the gene cluster and its product.
Cooperation and cheating orchestrate Vibrio assemblages and polymicrobial synergy in oysters infected with OsHV-1 virus
Authors: Oyanedel Daniel , Lagorce Arnaud , Bruto Maxime , Haffner Philippe , Morot Amandine , Labreuche Yannick , Dorant Yann , de La Forest Divonne Sébastien , Delavat François , Inguimbert Nicolas , Montagnani Caroline , Morga Benjamin , Toulza Eve , Chaparro Cristian , Escoubas Jean-Michel , Gueguen Yannick , Vidal-Dupiol Jeremie , de Lorgeril Julien , Petton Bruno , Degremont Lionel , Tourbiez Delphine , Pimparé Léa-Lou , Leroy Marc , Romatif Océane , Pouzadoux Juliette , Mitta Guillaume , Le Roux Frédérique , Charrière Guillaume M. , Travers Marie-Agnès , Destoumieux-Garzón Delphine
Published: September 2023

Polymicrobial infections threaten the health of humans and animals but remain understudied in natural systems. We recently described the Pacific Oyster Mortality Syndrome (POMS), a polymicrobial disease affecting oyster production worldwide. In the French Atlantic coast, the disease involves coinfection with ostreid herpesvirus 1 (OsHV-1) and virulent
Vibrio
. However, it is unknown whether consistent
Vibrio
populations are associated with POMS in different regions, how
Vibrio
contribute to POMS, and how they interact with OsHV-1 during pathogenesis. By connecting field-based approaches in a Mediterranean ecosystem, laboratory infection assays and functional genomics, we uncovered a web of interdependencies that shape the structure and function of the POMS pathobiota. We show that
Vibrio harveyi
and
Vibrio rotiferianus
are predominant in OsHV-1-diseased oysters and that OsHV-1 drives the partition of the
Vibrio
community observed in the field. However only
V. harveyi
synergizes with OsHV-1 by promoting mutual growth and accelerating oyster death.
V. harveyi
shows high-virulence potential and dampens oyster cellular defenses through a type 3 secretion system, making oysters a more favorable niche for microbe colonization. In addition,
V. harveyi
produces a key siderophore called vibrioferrin. This important resource promotes the growth of
V. rotiferianus
, which cooccurs with
V. harveyi
in diseased oysters, and behaves as a cheater by benefiting from
V. harveyi
metabolite sharing. Our data show that cooperative behaviors contribute to synergy between bacterial and viral coinfecting partners. Additional cheating behaviors further shape the polymicrobial consortium. Controlling cooperative behaviors or countering their effects opens avenues for mitigating polymicrobial diseases.
Spatial-Semantic Transformer for Spatial Relation Recognition
Authors: Peng Huilin , Wang Yang , Ge Hao
Published: September 2023

Spatial relation recognition, which aims to predict a spatial relation predicate, has attracted increasing attention in the computer vision study. During tackling this problem, modeling spatial relation of the subjects and objects is of great importance. We find that only using spatial features leads to poor results in predicting the spatial relation. To overcome these challenges, we propose an effective spatial attention module to enhance spatial features using semantic features. After identifying the importance of spatial attention mechanism, we propose a spatial transformer module with encoder layers to recognize unseen spatial relation based on spatial attention mechanism. Extensive experiments on the benchmark dataset (SpatialSense) show that, by using refined spatial feature, our spatial transformer model and spatial attention model achieve state-of-the-art performance on overall accuracy.
The Redesigning Icons to Reduce User Confusion
Authors: Satcharoen Kleddao , Bunyanuson Boonyawat , Siripreechawat Panassava , Tangtisanon Pikulkaew
Published: September 2023

Redesigning icons to reduce user confusion was created to solve the problems of Icons that are modelled on objects that are not popular for nowadays or are confusing to convey the meaning to the user to gain more effectively, increased accuracy and convenience for the user. A new icon design project to reduce user confusion. It arises from researching design-related information such as Affordance theory, image processing, color and mood theory, or even in terms of pixel size Which affects the use. Bring knowledge to design icons to better solve problems and respond to the needs of the user. This was done by collecting user data through questionnaires on the website with random questions and options. To take into account the performance of icons that are designed to find a suitable design for the use of that function.
Simulation and Optimization of the Operation Efficiency of Heat Exchange Units in Intelligent Heating Systems Based on Entransy Dissipation Thermal Resistance
Authors: Jia Zile , Sun Hao , Liu Dan , Zhao Meng , Lan Xingbo
Published: September 2023

So as to investigate heat exchange efficiency of heat exchange units under different operating conditions, this paper builds a simulation analysis model for heat exchange units in the framework of intelligent district heating systems based on the Modelica unified modeling language and the MWorks platform. Analyze the real-time operating efficiency of heat exchange units using entransy dissipation thermal resistance as an evaluation indicator of heat exchange efficiency. This paper analyzes the trend of heat exchange efficiency changes of heat exchange units when the primary side flow rate, secondary side flow rate, primary side inlet temperature, secondary side inlet temperature, and secondary side bypass pipeline valve opening change. The simulation results verify that when the primary side and the secondary side flow match, the entransy dissipation thermal resistance is the smallest, and its heat transfer efficiency is the highest. Under the simulation condition where the convective heat transfer coefficient is constant, the entransy dissipation thermal resistance is independent of the inlet temperature changes on the primary and secondary sides. The minimum entransy dissipation thermal resistance could be achieved, which represents the optimal real-time heat exchange efficiency state, when the valve opening of the mixed water heat exchange unit is 45% under the specific flow conditions.
Application of Acid Fracturing Technology to Improve Water Yield of Deep Carbonate Geothermal Wells
Authors: Zhang Zhiyong , Yang Beibei , Lv Xiaolan
Published: September 2023

To achieve the “carbon peak” goal, green and low-carbon energy development is the key. The development and utilization of geothermal resources and the development of deep carbonate geothermal wells in China are analyzed. Based on the principle of chemical reaction between hydrochloric acid and the main components of carbonate rock, four rock samples from geothermal wells were dissolved with 15% and 20% hydrochloric acid, respectively. The comparison showed that 15% hydrochloric acid was more economical and effective. The percolation capacity of acid dissolution fractures was tested through percolation capacity experiments, and the optimal amount of acid solution was determined to be 2-8 PV. It was verified that acid dissolution helps improve fracture percolation capacity. Through the on-site testing of acid fracturing technology in the Xiong’an New Area, it has been verified that the on-site implementation of multi-stage acid fracturing has a significant effect on increasing production. Finally, conclusions are drawn. The method of using acid solution dissolution to increase the water yield of deep carbonate geothermal wells is feasible, and the multi-stage acid fracturing technology is suitable for deep wells and can increase the water output of geothermal wells, which has good promotion value.
The effect of porous media on the thermal storage performance of salinity-gradient solar pond
Authors: Shao Zhengri , Wu Dan , Liang Jinguang , Cong Wei , Liang Kaijie
Published: September 2023

A solar pond is a system that uses a salt concentration gradient to store heat. The application of the system is conducive to solving the problems of long production cycles, low brine temperature, and salt algae in the solar pond lithium extraction process and the solar pond potassium enrichment process. Based on this, our research group laid porous media at the bottom of the solar pond and utilized the heat storage and adsorption capacity of porous media to improve the thermal storage performance of the solar pond. The experimental results show that foam ceramics have good thermal storage performance and the ability to reduce turbidity. Laying foam ceramics on the bottom of the solar pond can not only increase the thermal storage performance of LCZ but also help reduce the turbidity of the pool water. After adding porous media, the heat extraction position of the solar pool moves from the junction of LCZ and NCZ to the bottom of LCZ. In addition, adding transparent film on the upper surface of the solar pond is also conducive to improving the thermal storage performance of the solar pond and reducing the turbidity of the solar pond.
CFD simulation study of a biomass pellet-fuelled boiler
Authors: Yan Wuwu , Hao Xiaoling
Published: September 2023

Biomass energy is an important substitute for fossil energy. Direct combustion of biomass in the boiler has the problem of high emissions. In this paper, a 0.1 t/h biomass atmospheric pressure hot water boiler is used for CFD modeling, aiming at providing a low-cost and high-efficiency way for the study of biomass boilers. In this paper, the biomass pyrolysis process is divided into three processes: water evaporation, devolatilization, and coke combustion. Using the UDF function combined with a porous medium model to write code, the gas-solid combustion process in the boiler is realized, and the grate is used to split the air. The calculation results show that the model can accurately restore the temperature, velocity, and composition changes in the boiler. Compared with the actual results, the temperature difference between the furnace and the outlet is less than 20 K, and the modeling has achieved good results.
Study on optimization of household energy use considering photovoltaic access
Authors: Li Junshuang , Luo Xiao
Published: September 2023

Home access to photovoltaic and configuration energy storage can reduce the cost of energy consumption and suppress grid fluctuations. At the same time, various loads in the family can be divided into base loads and flexible loads according to their functional characteristics, some of them also be gas and electricity dual-use loads. This paper aims to reduce the energy consumption cost of households. Firstly, it classifies the loads in photovoltaic-connected households, optimizes the energy source selection of gas and electricity dual-use loads, and optimizes the scheduling of flexible loads’ working hours. Setting reasonable constraints while ensuring the primary energy demand of family members for each load reduces households’ dependence on external energy and energy expenditure. Moreover, the pressure on the regional energy supply can be alleviated by stabilizing the working time of flexible loads.
A numerical study on bubble dynamics and heat transfer of flow boiling in an inclined microchannel
Authors: Wang Haoyuan
Published: September 2023

Flow boiling, as an important heat transfer method, is widely applied in many devices. In this study, a gas-liquid thermal lattice Boltzmann model is adopted to study the flow boiling in an inclined microchannel. Specifically, the bubble growth processes and heat transfer efficiency are studied for different inclined angles. The numerical results show that the liquids occur phase change almost at the same time while the inclined angles are different. As the inclined angle increases, the bubble departure time decreases. Also, the heater temperatures change periodically for the studied cases. The maximum heater temperature is not affected by the inclined angle while the minimum heater temperature decreases when the inclined angle of the microchannel increases. Therefore, the larger inclined angle increases the flow boiling heat transfer efficiency.
Control Strategy of Distributed Battery Energy Storage System with Harmonic Compensation
Authors: Han Wei , Xu Zikun , Zhu Yueyao , Chen Ming , Zhang Jingwei
Published: September 2023

Based on the distributed battery energy storage system (BESS), a grid-connection strategy considering harmonic restraint is investigated. It can compensate the harmonic current to the grid by measuring the grid harmonics, then harmonic compensation is implemented to reduce the total harmonic distortion (THD) of the grid current. In this paper, the method of measuring harmonics in the grid and the control principle of providing power supply and harmonic compensation based on BESS are described. On this basis, the control flow is designed. Firstly, the energy storage grid-connected system is built in MATLAB/Simulink and the uncontrolled rectifier with inductive and resistance load is used for testing. The simulation results show that the grid current contains many harmonics, and the grid current THD decreases significantly by controlling BESS for harmonic compensation, which validates that the control method proposed in this paper is accurate and feasible.
A numerical study on the thermal hydraulic performance of finned elliptical tube with wet air flowing around
Authors: Dong Yue , Zhang Li
Published: September 2023

Energy conservation is a key concern for countries around the world. Enhanced heat exchange is one of the important ways to save energy. The heat transfer process of wet gas is a special heat transfer process, accompanied by a mass transfer phenomenon. Improving the thermal hydraulic performance of wet gas can greatly improve the energy utilization rate. The thermal hydraulic characteristic of finned elliptical tubes with different elliptical axis ratios (0.9 to 0.5) was numerically studied under wet air conditions. Chilton & Colburn factor was chosen as assessment parameters for the thermal performance. The mass transfer effect was characterized by a dehumidifying coefficient. The flow resistance coefficient was adopted to judge the flow characteristic and the London area goodness factor was evaluated for the overall performance. The simulations indicated the superior performance of the finned elliptical tube, j factor of the finned elliptical tube was greater and the flow resistance coefficient was less than that of the finned circular tube. Comparison between different finned elliptical tubes showed that the JF factor increased with the decrease of the elliptical axis ratio. Under the same inlet conditions, the JF factor increases by approximately 50% as the elliptical axis ratio changed from 1 to 0.5.
Energy storage steady-state PCS power allocation algorithm based on SOC dynamic sequencing
Authors: Li Li , Xiong Shangfeng , Zhu Shaojie , Sun Bo , He Chen
Published: September 2023

A power allocation algorithm for energy storage PCS based on SOC sequencing is proposed, aiming at the problem that the energy management system (EMS) can allocate the power of the energy storage unit power converter (PCS) in the existing centralized electrochemical energy storage station steady-state power control, and cannot take into account the equalization of the state of charge (SOC) of the energy storage unit and the power control accuracy of the whole station. Based on the analysis of the characteristics of PCS power allocation algorithms commonly used in engineering, this paper proposes an algorithm to determine the PCS control priority based on the SOC ranking results, and then realize PCS power allocation. The simulation results show that compared with other steady-state PCS power allocation algorithms, the algorithm proposed in this paper can enable the whole station to achieve a better balance of the SOC of the energy storage unit under the premise of satisfying the power control accuracy, so that the energy storage station can provide better steady-state power support for the power grid.
Initial Pressure Optimization of Thermal Power Unit under Deep Variable Operating Conditions
Authors: Niu Baifang , Li Hu , Chen Wenxin , Han Hongjun
Published: September 2023

Aiming at the problem of how to adjust the main steam pressure under the load instruction from the frequency modulation of the power grid to make the operation safer and more economical in the process of peak regulation, we take that 650 MW reheating condensed steam turbine as the research object. This paper introduces some domestic scholars’ research status of initial pressure optimization. The model is established by using EBSILON Professional thermodynamic system simulation software and combining it with the heat balance diagram of the power plant under VWO working conditions. The initial pressure optimization under deep variable working conditions is studied, then introduces the operation mode of the steam turbine under variable working conditions during peak shaving. The mathematical relationship between heat consumption rate and initial pressure was established to determine the feasible range of initial pressure. The exhaustive method traverses the feasible pressure interval under a particular working condition. The heat consumption rate under each pressure was calculated to screen out the optimal initial pressure and optimize the initial pressure curve.
A combined wind-PV power prediction method based on clustering prescreening
Authors: Su Yunhan , Yu Zhuangzhuang , Lv Meijing , Luo Huan
Published: September 2023

Due to the volatility caused by the high uncertainty of renewable energy, the large-scale integration of renewable energy into the electric power grid brings huge challenges to the scheduling and operation of the electric power system. Effective power prediction of power source can not only relieve the pressure of power system peaking and frequency regulation, but also improve the accuracy of decision-making. So as to make the most of the information between wind and photovoltaic power source, this paper puts forward a wind-PV joint power forecasting model. First, the raw power data is pre-screened by clustering to select the closer connection between wind and PV power; next, the screened data are passed through the upper CNN structure respectively after pre-processed. Then, the outputs from CNN modules are fed together into the prediction layer, which include LSTM layers and fully connected layers. Finally, the proposed wind-PV joint prediction model is verified by simulation experiments.
Experimental Study on Heat Transfer Enhancement of Modified CuO Nanofluid in Helical Grooved Tube
Authors: Zhao Shanguo , Hai Guangmei , Ma Hongtao , Huang Long , Liu Zhaoliang
Published: September 2023

This study proposes a novel technology to enhance heat transfer by combining nanofluid and helical grooved tubes. The researchers used a two-step method to obtain a stable modified CuO nanofluid. They then constructed an experimental setup to investigate the single-phase heat transfer of the nanofluid in a helical grooved tube, and compared its performance to traditional methods under varying volume fractions and Reynolds numbers. The experimental results indicate that the use of nanofluid in the helical grooved tube significantly improves the convective heat transfer coefficient. Furthermore, the heat transfer coefficient increases gradually with the addition of nanoparticle volume fraction and Reynolds number. The helical grooved tube’s internal structure causes local turbulence at low Reynolds numbers, intensifying the nano-scale eddies and turbulence inside the nanofluid, enhancing fluid mixing and thermal diffusion rates, and thus improving the heat transfer efficiency.
An MMC control strategy without bridge arm current sensors
Authors: Chen Yanming , Zhao Mingkai , Zhang Zhao , Zeng Sencai
Published: September 2023

Each bridge arm of a modular multilevel converter (MMC) is connected in series with multiple submodules. This structure increases the amount of current detection, making it necessary to have a number of current sensors in operation, which increases the system cost. For this reason, this paper proposes an MMC control strategy that does not require bridge arm current sensors. Firstly, the nearest level modulation (NLM) strategy requires the bridge arm current to be used to determine the submodule entry direction. In this case, this article proposes a method for determining the input direction of the submodule based on the capacitive voltage of the submodule, which calculates the input method of the submodule by analyzing the state quantities in the bridge arm voltage switching function, omitting the bridge arm current sensor and reducing the cost. Secondly, the traditional MMC circulation suppression method needs to detect the bridge arm current to calculate the circulation. However, this paper proposes an indirect circulation suppression method by suppressing the unbalanced voltage based on the analysis of the circulation generation mechanism. Finally, simulations and experiments validate the effectiveness of this method and lay the foundation for the next engineering application.
Multi-stage Drive of Switched Reluctance Motor Based on Ring Winding Structure
Authors: Zhao Zhenyu , Dou Yinke , Sun Haitao , Wang Ruihao , Shao Mingzhi
Published: September 2023

A new ring winding structure can drive switched reluctance motors (SRMs). It uses a full-bridge power converter circuit to drive SRMs and is significant for developing SRMs. For this structure, this paper proposes an optimization strategy. A voltage regulator is used to boost the winding current during the motor starting phase to ensure the average starting and low-speed operation of the motor. After the motor speed reaches a specific value, the passive device replaces the voltage regulator, which ensures the stable operation of the SRM while reducing the frequency of the voltage regulator and improving the service life of the regulator. This paper simulates the optimization strategy of the ring winding structure and derives the calculation method for switching speed.
Voltage Equalization Control Method for ships and warships Supercapacitor Charging
Authors: Bu Susu
Published: September 2023

A DC-DC converter voltage balancing controller with added voltage anti overcharging protection device is proposed to address the voltage balancing control problem of supercapacitors used in Ships and warships. A simulation model is built in the PSIM environment, and through simulation experiments, this balancing controller can improve the voltage balancing rate, reduce space occupation, and prevent overcharging phenomena. The simulation results show that the improved DC-DC voltage balance controller has a detailed improvement effect on the charging voltage balance of ship supercapacitors.
Modeling and simulation of extra high voltage magnetically controlled shunt reactor based on PSCAD
Authors: Wu Haiyan , Wang Liqiang , Xing Huadong , Liu Ziyu , Zhang Aijun
Published: September 2023

For the two typical topologies of the extra high voltage magnetically controlled shunt reactor (MCSR), this study introduces its specific wiring methods and working principles. It conducts an analysis of the change characteristics and response characteristics of the core magnetic flux under different wiring modes of the controlled shunt reactor body. Based on PSCAD, two typical structures are used to model the body of the first 500 kV MCSR put into operation in a provincial power grid and perform steady-state and dynamic simulations. The results of field experiments are compared and analyzed. The winding connection mode of the device’s body electromagnetic transient model is determined, which lays a foundation for the follow-up research.