On Unitary N-Dilations for Tuples of Circulant Contractions and von Neumann’s Inequality

We introduce the spectral mapping factorization of tuples of circulant matrices and its matrix version. We prove that every tuple of circulant contractions has a unitary N-dilation. We show that von Neumann’s inequality holds for tuples of circulant contractions. We construct completely contractive homomorphisms over the algebra of complex polynomials defined on .

Esophageal dilations in eosinophilic esophagitis: A single center experience

AIM:To diagnose the clinical and histologic features that may be associated with or predictive of the need for dilation and dilation related complications;examine the safety of dilation in patients with eosinophilic esophagitis(EoE).METHODS:The medical records of all patients diagnosed with EoE between January 2002 and July 2010were retrospectively reviewed.Esophageal biopsies were reexamined by an experienced pathologist to confirm the diagnosis(≥15 eos/hpf per current guidelines).Patients were divided into 2 groups:patients who did not receive dilation therapy and those who did.Demographics,clinical history,the use of pharmacologic therapy,endoscopic and pathology findings,and the number of biopsies and dilations carried out,if any,and their locations were recorded for each patient.The dilation group was further examined based on the interval between diagnosis and dilation,and whether or not a complication occurred.RESULTS:Sixty-one patients were identified with EoE and 22(36%)of them underwent esophageal dilations for stricture/narrowing.The peak eos/hpf was significantly higher in patients who received a dilation(P=0.04).Four(18%of pts.)minor complications occurred:deep mucosal tear 1,and small mucosal tears3.There were no cases of esophageal perforations.Higher peak eos/hpf counts were not associated with increased risk of complications.CONCLUSION:Esophageal dilation appears to be a safe procedure in EoE patients,carrying a low complication rate.No correlation was found between the peak of eosinophil count and complication rate.Complications can occur independently of the histologic features.The long-term outcome of EoE treatment,with or without dilation,needs to be determined.

A Sort of Gray-scale Morphological Dilations and Erosions

We introduce first a sort of gray-scale morphological dilations and erosions, which might have some further applications in image analysis. Then we show that the dilation and the erosion defined here form adjunctive pairs. The duality between the dilation and the erosion and some other properties, such as the commuting property with translation and homothety, of these operators are discussed as well.

A characterization of generator for multiresolution analysis with composite dilations

In this paper, we will introduce multiresolution analysis with composite dilations and give a characterization of generator for multiresolution analysis with composite dilations.

经鼓室口咽鼓管球囊扩张术的疗效及咽鼓管功能的影响

目的探讨经鼓室口咽鼓管球囊扩张(balloon dilatation Eustachian tuboplasty,BET)联合腺样体消融术对慢性分泌性中耳炎(chronic secretory otitis media,CSOM)患儿的疗效及咽鼓管功能的影响。方法选取2020年6月~2022年12月间在中山市小榄人民医院就诊的CSOM患儿82例作为研究对象,采用随机数字表法分为对照组和观察组,每组41例。对照组接受腺样体消融术+鼓膜切开置管术治疗,观察组接受腺样体消融术+鼓膜切开置管术+BET术。比较两组手术相关指标及住院时间、临床症状、咽鼓管功能、临床疗效及随访6个月并发症及复发情况。结果两组术中出血量比较,差异无统计学意义(P>0.05),与对照组相比,观察组手术时间更长,住院时间更短(P<0.05)。与对照组相比,观察组中耳积液消失时间、耳鸣消失时间、鼓膜愈合时间、听力恢复时间均更短(P<0.05)。与治疗前相比,治疗后两组咽鼓管评分(Eustachian tube score,ETS)升高、咽鼓管功能障碍评分量表(Eustachian tube dysfunction questionnaire-7,ETDQ-7)评分降低(P<0.05),观察组ETS评分高于对照组,ETDQ-7评分则低于对照组(P<0.05)。观察组临床总有效率高于对照组,差异具有统计学意义(P<0.05)。两组并发症发生率比较,差异无统计学意义(14.63%vs.9.76%,P>0.05),与对照组相比,观察组复发率更低,差异具有统计学意义(21.95%vs.2.44%,P<0.05)。结论经鼓室口BET联合腺样体消融术有助于提高CSOM患儿的临床疗效,改善咽鼓管功能,促进术后恢复,减少复发率,且并发症发生率低。

The Whole Theory of This Universe—A Step Forward to Einstein. Part-4: “Concept Map of Rotating Universe”

The article collectively proposes a revolutionary perspective on the universe, intertwining concepts of time, spatial positioning, and cosmic dynamics. We introduce the idea of a rotating universe centered around Mega Central Energy Pools (MCEPs), where time varies relative to the distance from the universe’s center, potentially enabling time travel. This model challenges conventional notions of time and cosmology, suggesting that black holes and white holes act as cosmic recycling factories. Additionally, this model unveils a novel theory of dark matter, positing photons as its constituents and highlighting their role in energy transfer across the cosmos. Furthermore, the investigation into Venus’s unique day-length-to-year-length ratio unveils a microscopic mechanism involving swirling energy droplets, charged particles, and field interactions, offering insights into planetary dynamics on both micro and macro scales.

超声辅助与纤维支气管镜辅助经皮扩张气管切开术的对比研究

目的探讨超声辅助经皮扩张气管切开术的应用价值。方法回顾性分析2020年12月~2022年12月在甘肃省人民医院重症医学科行经皮扩张气管切开术患者56例,均经口气管插管后呼吸机辅助呼吸,根据不同的辅助方式分为超声辅助(超声组)31例和纤维支气管镜辅助(纤维支气管镜组)25例。结果与纤维支气管镜组比较,超声组术中氧合指数(PaO_(2)/FiO_(2))增高[(157.3±19.2)mmHg vs.(145.4±22.8)mmHg,t=2.117,P=0.039],分钟通气(MV)量增高[(7.3±0.8)L/min vs.(6.1±0.7)L/min,t=5.278,P<0.001],动脉血二氧化碳分压(PCO_(2))降低[(39.1±4.8)mmHgvs.(44.3±5.6)mmHg,t=-3.709,P<0.001],术后出血例数减少[0例vs.4例,χ^(2)=5.246,P=0.022]。结论超声组较纤维支气管镜组行经皮扩张气管切开术手术并发症少,安全性高。

Homogeneous Approximation Property for Wavelet Frames with Matrix Dilations,Ⅱ

The homogeneous approximation property （HAP） states that the number of building blocks involved in a reconstruction of a function up to some error is essentially invariant under time-scale shifts. In this paper, we show that every wavelet frame with nice wavelet function and arbitrary expansive dilation matrix possesses the HAP. Our results improve some known ones.

Numerical modelling of post-failure behaviors of coal specimens

A modelling approach consisting of best-fit relations to estimate the post-yield strength parameters is presented for simulating post-peak behavior beyond the point of residual strength of coal pillars having different w/h ratios.The model was developed based on back-analysis of the complete stress-strain behavior of specimens belonging to six different Indian coal seams with different w/h ratios of 0.5 e13.5.It was found that the simultaneous degradation of the cohesion and friction angle of the Mohr-Coulomb rock material characterizes the post-peak strength behavior of the rock.The resulting expressions are simplistic as they require parameters that can be easily determined using uniaxial and triaxial compression results.Eventually,the developed model was validated by simulating the triaxial tests of coal specimens with different sizes under varying confining stresses and comparing its findings with the published test results.The study showed that its implementation in the numerical model could reproduce laboratory-observed mechanical response,deformation behavior,and failure mechanism very closely.

TSCND:Temporal Subsequence-Based Convolutional Network with Difference for Time Series Forecasting

Time series forecasting plays an important role in various fields, such as energy, finance, transport, and weather. Temporal convolutional networks (TCNs) based on dilated causal convolution have been widely used in time series forecasting. However, two problems weaken the performance of TCNs. One is that in dilated casual convolution, causal convolution leads to the receptive fields of outputs being concentrated in the earlier part of the input sequence, whereas the recent input information will be severely lost. The other is that the distribution shift problem in time series has not been adequately solved. To address the first problem, we propose a subsequence-based dilated convolution method (SDC). By using multiple convolutional filters to convolve elements of neighboring subsequences, the method extracts temporal features from a growing receptive field via a growing subsequence rather than a single element. Ultimately, the receptive field of each output element can cover the whole input sequence. To address the second problem, we propose a difference and compensation method (DCM). The method reduces the discrepancies between and within the input sequences by difference operations and then compensates the outputs for the information lost due to difference operations. Based on SDC and DCM, we further construct a temporal subsequence-based convolutional network with difference (TSCND) for time series forecasting. The experimental results show that TSCND can reduce prediction mean squared error by 7.3% and save runtime, compared with state-of-the-art models and vanilla TCN.

Dilation,discrimination and Uhlmann's theorem of link products of quantum channels

We establish the Stinespring dilation theorem of the link product of quantum channels in two different ways,discuss the discrimination of quantum channels,and show that the distinguishability can be improved by self-linking each quantum channel n times as n grows.We also find that the maximum value of Uhlmann's theorem can be achieved for diagonal channels.

Failure transition of shear-to-dilation band of rock salt under triaxial stresses

Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily or even hourly,which generates complicated pressures on the salt cavern.Furthermore,the mechanical behavior of rock salt may change and present distinct failure characteristics under different stress states,which affects the performance of salt cavern during the time period of full service.To reproduce a similar loading condition on the cavern surrounding rock mass,the cyclic triaxial loading/unloading tests are performed on the rock salt to explore the mechanical transition behavior and failure characteristics under different confinement.Experimental results show that the rock salt samples pre-sent a diffused shear failure band with significant bulges at certain locations in low confining pressure conditions(e.g.5 MPa,10 MPa and 15 MPa),which is closely related to crystal misorientation and grain boundary sliding.Under the elevated confinement(e.g.20 MPa,30 MPa and 40 MPa),the dilation band dominates the failure mechanism,where the large-size halite crystals are crushed to be smaller size and new pores are developing.The failure transition mechanism revealed in the paper provides additional insight into the mechanical performance of salt caverns influenced by complicated stress states.

Preliminary exploration of animal models of congenital choledochal cysts

BACKGROUND Various animal models have been used to explore the pathogenesis of choledochal cysts(CCs),but with little convincing results.Current surgical techniques can achieve satisfactory outcomes for treatment of CCs.Consequently,recent studies have focused more on clinical issues rather than basic research.Therefore,we need appropriate animal models to further basic research.AIM To establish an appropriate animal model that may contribute to the investigation of the pathogenesis of CCs.METHODS Eighty-four specific pathogen-free female Sprague-Dawley rats were randomly allocated to a surgical group,sham surgical group,or control group.A rat model of CC was established by partial ligation of the bile duct.The reliability of the model was confirmed by measurements of serum biochemical indices,morpho-logy of common bile ducts of the rats as well as molecular biology experiments in rat and human tissues.RESULTS Dilation classified as mild(diameter,≥1 mm to<3 mm),moderate(≥3 mm to<10 mm),and severe(≥10 mm)was observed in 17,17,and 2 rats in the surgical group,respectively,while no dilation was observed in the control and sham surgical groups.Serum levels of alanine aminotransferase,aspartate aminotrans-ferase,total bilirubin,direct bilirubin,and total bile acids were significantly elevated in the surgical group as compared to the control group 7 d after surgery,while direct bilirubin,total bilirubin,and gamma-glutamyltransferase were further increased 14 d after surgery.Most of the biochemical indices gradually decreased to normal ranges 28 d after surgery.The protein expression trend of signal transducer and activator of transcription 3 in rat model was consistent with the human CC tissues.CONCLUSION The model of partial ligation of the bile duct of juvenile rats could morphologically simulate the cystic or fusiform CC,which may contribute to investigating the pathogenesis of CC.

Polyneuropathy, organomegaly, endocrinopathy, M-protein, skin changes syndrome with dilated cardiomyopathy: A case report

BACKGROUND Polyneuropathy,organomegaly,endocrinopathy,M-protein,skin changes(POEMS)syndrome is a rare paraneoplastic syndrome that encompass multiple systems.The most common clinical symptoms of POEMS syndrome are pro-gressive sensorimotor polyneuropathy,organ enlargement,endocrine disorders,darkening skin,a monoclonal plasma cell proliferative disorder,and lymph node hyperplasia.The organomegaly consists of hepatosplenomegaly and/or lym-phadenopathy;cases of cardiomyopathy are rare.Diagnoses are often delayed because of the atypical nature of the syndrome,exposing patients to possibly severe disability.Therefore,identifying atypical symptoms can improve the prognosis and quality of life among POEMS syndrome patients.lenalidomide and dexamethasone.CONCLUSION When patients with cardiomyopathy have systemic manifestations such as numb limbs and darkening skin,the POEMS syndrome is the most possible diagnosis.

Cardiac remodeling in patients with atrial fibrillation reversing bradycardia-induced cardiomyopathy:A case report

BACKGROUND Bradycardia-induced cardiomyopathy(BIC),which is a disease resulting from bradycardia,is characterized by cardiac chamber enlargement and diminished cardiac function.The correction of bradycardia can allow for significant improvements in both cardiac function and structure;however,this disease has been infrequently documented.In this case,we conducted a longitudinal followup of a patient who had been enduring BIC for more than 40 years to heighten awareness and prompt timely diagnosis and rational intervention.CASE SUMMARY A woman who presented with postactivity fatigue and dyspnea was diagnosed with bradycardia at the age of 7.Since she had no obvious symptoms,she did not receive any treatment to improve her bradycardia during the 42-year follow-up,except for the implantation of a temporary pacemaker during labor induction surgery.As time progressed,the patient's heart gradually expanded due to her low ventricular rate,and she was diagnosed with BIC.In 2014,the patient developed atrial fibrillation,her ventricular rate gradually increased,and her heart shape gradually returned to normal.This report describes the cardiac morphological changes caused by the heart rate changes in BIC patients older than 40 years,introduces another possible outcome of BIC,and emphasizes the importance of early intervention in treating BIC.CONCLUSION BIC can induce atrial fibrillation,causing an increased ventricular rate and leading to positive cardiac remodeling.

Response letter to “Acute cholangitis: Does malignant biliary obstruction vs choledocholithiasis etiology change the outcomes?” with imaging aspects

Radiological imaging findings may contribute to the differentiation of malignant biliary obstruction from choledocholithiasis in the etiology of acute cholangitis.

Imaging features of malignant vs stone-induced biliary obstruction:Aspects to consider

Radiological studies play a crucial role in the evaluation of patients with biliary duct obstruction,allowing for the guidance of clinical diagnosis towards a malignant or stone-induced etiology through the recognition of relevant imaging features,which must be continuously revisited given their prognostic significance.This article aims to emphasize the importance of recognizing crucial imaging aspects of malignant and stone-induced biliary obstruction.

Giant bile duct dilatation in newborn:A case report

BACKGROUND Giant congenital biliary dilation(CBD)is a rare condition observed in clinical practice.Infants born with this condition often experience a poor overall health status,and the disease progresses rapidly,leading to severe biliary obstruction,infections,pressure exerted by the enlarged CBD on abdominal organs,disturbances in the internal environment,and multiple organ dysfunction.The treatment of giant CBD using laparoscopy is challenging due to the high degree of variation in the shape of the bile duct and other organs,making it difficult to separate the bile duct wall from adjacent tissues or to control bleeding.CASE SUMMARY Herein,we present the details of an 11-d-old male newborn who was diagnosed with giant CBD.The patient was admitted to the neonatal surgery department of our hospital due to a history of common bile duct cyst that was detected more than 3 mo ago,and also because the patient had been experiencing yellowish skin for the past 9 d.The abnormal echo in the fetal abdomen was first noticed by the patient’s mother during a routine ultrasound examination at a local hospital,when the patient was at 24 wk+6 d of pregnancy.This finding raised concerns about the possibility of congenital biliary dilatation(22 mm×21 mm).Subsequent ultrasound examinations at different hospitals consistently confirmed the presence of a congenital biliary dilatation.No specific treatment was administered for biliary dilatation during this period.A computed tomography scan conducted during the hospitalization revealed a large cystic mass in the right upper quadrant and pelvis,measuring approximately 9.2 cm×7.4 cm×11.3 cm.Based on the CONCLUSION The analysis reveals that prenatal imaging techniques,such as ultrasound and magnetic resonance imaging,play a crucial role in the early diagnosis,fetal prognosis,and treatment plan for giant CBD.Laparoscopic surgery for giant CBD presents certain challenges,including difficulties in separating the cyst wall,anastomosis,and hemostasis,as well as severe biliary system infection and ulceration.Consequently,there is a high likelihood of converting to laparotomy.The choice between surgical methods like hepaticojejunostomy(HJ)or hepaticoduodenostomy has not been standardized yet.However,we have achieved favorable outcomes using HJ.Preoperative management of inflammation,biliary drainage,liver function protection,and supportive treatment are particularly vital in improving children’s prognosis.After discharge,it is essential to conduct timely reexamination and close follow-up to identify potential complications.

Endoscopic treatment of extreme esophageal stenosis complicated with esophagotracheal fistula: A case report

BACKGROUND At present,there is no unified and effective treatment for extreme corrosive esophageal stenosis(CES)with esophagotracheal fistula(ETF).This case had extreme and severe esophageal stenosis(ES)and ETF after ingesting an enzyme-based chemical detergent,resulting in a serious pulmonary infection and severe malnutrition.Upper gastrointestinal imaging showed that he had an ETF,and endoscopy showed that he had extreme and severe esophageal stricture.This case was complex and difficult to treat.According to the domestic and foreign lite-rature,there is no universal treatment that is low-risk.CASE SUMMARY A patient came to our hospital with extreme ES,an ETF,and severe malnutrition complicated with pulmonary tuberculosis 1 mo after the consumption of an enzy-me-based detergent.The ES was serious,and the endoscope was unable to pass through the esophagus.We treated him by endoscopic incision method(EIM),esophageal stent placement(ESP),and endoscopic balloon dilation(EBD)by using the bronchoscope and gastroscope.This treatment not only closed the ETF,but also expanded the esophagus,with minimal trauma,greatly reducing the pain of the patient.According to the literature,there are no similar reported cases.CONCLUSION We report,for the first time,a patient with extreme CES complicated with ETF,where the endoscope could not be passed through his esophagus but he could be examined by bronchoscopy and treated by EIM,ESP,and EBD.

Balloon dilation of congenital perforated duodenal web in newborns: Evaluation of short and long-term results

BACKGROUND Incomplete congenital duodenal obstruction(ICDO)is caused by a congenitally perforated duodenal web(CPDW).Currently,only six cases of balloon dilatation of the PDW in newborns have been described.AIM To present our experience of balloon dilatation of a perforated duodenal memb-rane in newborns with ICDO.METHODS Five newborns who underwent balloon dilatation of the CPDW along a prein-stalled guidewire between 2021 and 2023 were included.Nineteen newborns diagnosed with ICDO who underwent laparotomy were included in the control group.RESULTS In all cases,good anatomical and clinical results were obtained.In three cases,a follow-up study was conducted after 1 year.The average time to start enteral feeding per os was significantly earlier in the study group(4.4 d)than in the laparotomic group(21.2 days;P<0.0001).The time spent by patients in the intensive care unit and hospital after balloon dilatation was also significantly shorter.We determined the selection criteria for possible and effective CPDW balloon dilatation in newborns as follows:(1)Presence of dynamic radiographic signs of the passage of a radiopaque substance beyond the zone of narrowing or radiographic signs of pneumatisation of the duodenum and small bowel distal to the web;(2)presence of endoscopic signs of CPDW;(3)successful cannulation with a guidewire performed parallel to the endoscope,with holes in the congenital duodenal web;and(4)successful positioning of the balloon performed along a freestanding guidewire on the web.CONCLUSION Strictly following selection criteria for newborns with ICDO caused by CPDW ensures that endoscopic balloon dilatation using a pre-installed guidewire is safe and effective and shows good 1-year follow-up results.