bluuebunny/crossref_metadata_2025 huggingface dataset:
Periodic solutions of two-dimensional wave equations with x-dependent coefficients and Sturm–Liouville boundary conditions
Authors: Ji Shuguan
Published: September 2022

This paper considers the periodic solutions of a two-dimensional nonlinear wave equation with x-dependent coefficients

v

(

x

)

y

t
t

−

(

v

(

x

)

y

x

1

)

x

1

−

(

v

(

x

)

y

x

2

)

x

2

+
β
y
+
g

(

y

)

=
f

(

x
,
t

)

,

subject to the Sturm–Liouville boundary conditions

a

11

y

(

0
,

x

2

,
t

)

−

b

11

y

x

1

(

0
,

x

2

,
t

)

=
0
,

a

12

y

(

π
,

x

2

,
t

)

+

b

12

y

x

1

(

π
,

x

2

,
t

)

=
0
,

a

21

y

(

x

1

,
0
,
t

)

−

b

21

y

x

2

(

x

1

,
0
,
t

)

=
0
,

a

22

y

(

x

1

,
π
,
t

)

+

b

22

y

x

2

(

x

1

,
π
,
t

)

=
0
,

where x = (x
1, x
2) ∈ (0, π) × (0, π),

t
∈
R

and

a

i
j

2

+

b

i
j

2

≠
0

for i, j = 1, 2. Such a model arises from the forced vibrations of a nonhomogeneous membrane and the propagation of waves in nonhomogeneous media. By using the duality principles of Brézis (1983 Bull. Am. Math. Soc.
8 409–26), we first set up the theoretical framework and give an abstract theorem for the existence of periodic solution. Then, by analysing the spectral asymptotic behaviours of the weighted Sturm–Liouville problem and classifying the boundary conditions, we obtain the fundamental properties of the variable coefficients wave operator under appropriate assumptions for different class of boundary conditions. Finally, based on these properties and with the help of the abstract theorem, we establish some results on the existence and regularity of periodic solutions. To the best of our knowledge, the results are entirely new, and this is the first time to obtain such results for the two-dimensional nonlinear wave equation with x-dependent coefficients.
Energy conservation in the limit of filtered solutions for the 2D Euler equations
Authors: Gotoda Takeshi
Published: September 2022

We consider energy conservation in a two-dimensional incompressible and inviscid flow through weak solutions of the filtered-Euler equations, which describe a regularized Euler flow based on a spatial filtering. We show that the energy dissipation rate for the filtered weak solution with vorticity in L

p
, p > 3/2 converges to zero in the limit of the filter parameter. Although the energy defined in the whole space is not finite in general, we formally extract a time-dependent part, which is well-defined for filtered solutions, from the energy and define the energy dissipation rate as its time-derivative. Moreover, the limit of the filtered weak solution is a weak solution of the Euler equations and it satisfies a local energy balance in the sense of distributions. For the case of p = 3/2, we find the same result as p > 3/2 by assuming Onsager’s critical condition for the family of the filtered solutions.
On families of constrictions in model of overdamped Josephson junction and Painlevé 3 equation*
Authors: Bibilo Y , Glutsyuk A A
Published: September 2022

The tunnelling effect predicted by Josephson (Nobel Prize, 1973) concerns the Josephson junction: two superconductors separated by a narrow dielectric. It states existence of a supercurrent through it and equations governing it. The overdamped Josephson junction is modelled by a family of differential equations on two-torus depending on three parameters: B (abscissa), A (ordinate), ω (frequency). We study its rotation number
ρ(B, A; ω) as a function of (B, A) with fixed ω. The phase-lock areas are the level sets L

r
≔ {ρ = r} with non-empty interiors; they exist for

r
∈
Z

(Buchstaber, Karpov, Tertychnyi). Each L

r
is an infinite chain of domains going vertically to infinity and separated by points. Those separating points for which A ≠ 0 are called constrictions. We show that: (1) all the constrictions in
L

r

lie on the axis {B = ωr}; (2) each constriction is positive: this means that some its punctured neighbourhood on the axis {B = ωr} lies in Int(L

r
). These results confirm experiments by physicists (1970ths) and two mathematical conjectures. We first prove deformability of each constriction to another one, with arbitrarily small ω and the same

ℓ
≔

B

ω

, using equivalent description of model by linear systems of differential equations on

C

¯

(Buchstaber, Karpov, Tertychnyi) and studying their isomonodromic deformations described by Painlevé 3 equations. Then non-existence of ghost constrictions (i.e., constrictions either with

ρ
≠
ℓ
=

B

ω

, or of non-positive type) with a given ℓ for small ω is proved by slow-fast methods.
Mean dimension of Bernstein spaces and universal real flows
Authors: Jin Lei , Qiao Yixiao , Tu Siming
Published: September 2022

We study the action of translation on the spaces of uniformly bounded continuous functions on the real line which are uniformly band-limited in a compact interval. We prove that two intervals themselves will decide if two spaces are topologically conjugate, while the length of an interval tells the mean dimension of a space. We also investigate universal real flows. We construct a sequence of compact invariant subsets of a space consisting of uniformly bounded smooth one-Lipschitz functions on the real line, which have mean dimension equal to one, such that all real flows can be equivariantly embedded in the translation on their product space. Moreover, we show that the countable self-product of any among them does not satisfy such a universal property. This, on the one hand, presents a more reasonable choice of a universal real flow with a view towards mean dimension, and on the other hand, clarifies a seemingly plausible impression; meanwhile, it refines the previously known results in this direction. Our proof goes through an approach of harmonic analysis. Furthermore, both the universal space that we provide and an embedding mapping which we build for any real flow are explicit.
Dynamic study of pendulum systems through smartphone-based laboratory experiments
Authors: Ait Ben Ahmed A , Touache A , ElHakimi A , Chamat A
Published: September 2022

The dynamic study of pendulum systems is considered an indispensable subject for physics and mechanics students in colleges and high schools. In this paper, a detailed methodology is given concerning the use of smartphones in pedagogical practical work for studying the dynamics of pendulum systems. Whereas, three aspects have been discussed through three cases concerning the study of the oscillatory motion, trajectories, and the energy aspect. Besides, some recommendations were provided regarding the process of data acquisition and curve-fitting processing to mitigate measurement errors. Experimental results exhibit a good agreement with theoretical results regarding the period of motion, trajectories, and mechanical energy. This makes the smartphone highlights a real opportunity to be a useful instrument to perform an overall study of the pendulum systems, the thing that was impossible without the intervention of professional equipment.
Generation of 18F-FDG PET standard scan images from short scans using cycle-consistent generative adversarial network
Authors: Ghafari Ali , Sheikhzadeh Peyman , Seyyedi Negisa , Abbasi Mehrshad , Farzenefar Saeed , Yousefirizi Fereshteh , Ay Mohammad Reza , Rahmim Arman
Published: September 2022

Objective. To improve positron emission tomography (PET) image quality, we aim to generate images of quality comparable to standard scan duration images using short scan duration (1/8 and 1/16 standard scan duration) inputs and assess the generated standard scan duration images quantitative and qualitatively. Also, the effect of training dataset properties (i.e. body mass index (BMI)) on the performance of the model(s) will be explored. Approach. Whole-body PET scans of 42 patients (41 18F-FDG and one 68Ga-PSMA) scanned with standard radiotracer dosage were included in this study. One 18F-FDG patient data was set aside and the remaining 40 patients were split into four subsets of 10 patients with different mean patient BMI. Multiple copies of a developed cycle-GAN network were trained on each subset to predict standard scan images using 1/8 and 1/16 short duration scans. Also, the models’ performance was tested on a patient scanned with the 68Ga-PSMA radiotracer. Quantitative performance was tested using peak signal-to-noise ratio (PSNR), structural similarity index (SSIM), and normalized root mean squared error (NRMSE) metrics, and two nuclear medicine specialists analyzed images qualitatively. Main results. The developed cycle-GAN model improved the PSNR, SSIM, and NRMSE of the 1/8 and 1/16 short scan duration inputs both 18F-FDG and 68Ga-PSMA radiotracers. Although, quantitatively PSNR, SSIM, and NRMSE of the 1/16 scan duration level were improved more than 1/8 counterparts, however, the later were qualitatively more appealing. SUVmean and SUVmax of the generated images were also indicative of the improvements. The cycle-GAN model was much more capable in terms of image quality improvements and speed than the NLM denoising method. All results proved statistically significant using the paired-sample T-Test statistical test (p-value < 0.05). Significance. Our suggested approach based on cycle-GAN could improve image quality of the 1/8 and 1/16 short scan-duration inputs through noise reduction both quantitively (PSNR, SSIM, NRMSE, SUVmean, and SUVmax) and qualitatively (contrast, noise, and diagnostic capability) to the level comparable to the standard scan-duration counterparts. The cycle-GAN model(s) had a similar performance on the 68Ga-PSMA to the 18F-FDG images and could improve the images qualitatively and quantitatively but requires more extensive study. Overall, images predicted from 1/8 short scan-duration inputs had the upper hand compared with 1/16 short scan-duration inputs.
Iterative tomographic reconstruction with TV prior for low-dose CBCT dental imaging
Authors: Friot--Giroux Louise , Peyrin Françoise , Maxim Voichita
Published: September 2022

Objective. Cone-beam computed tomography is becoming more and more popular in applications such as 3D dental imaging. Iterative methods compared to the standard Feldkamp algorithm have shown improvements in image quality of reconstruction of low-dose acquired data despite their long computing time. An interesting aspect of iterative methods is their ability to include prior information such as sparsity-constraint. While a large panel of optimization algorithms along with their adaptation to tomographic problems are available, they are mainly studied on 2D parallel or fan-beam data. The issues raised by 3D CBCT and moreover by truncated projections are still poorly understood. Approach. We compare different carefully designed optimization schemes in the context of realistic 3D dental imaging. Besides some known algorithms, SIRT-TV and MLEM, we investigate the primal-dual hybrid gradient (PDHG) approach and a newly proposed MLEM-TV optimizer. The last one is alternating EM steps and TV-denoising, combination not yet investigated for CBCT. Experiments are performed on both simulated data from a 3D jaw phantom and data acquired with a dental clinical scanner. Main results. With some adaptations to the specificities of CBCT operators, PDHG and MLEM-TV algorithms provide the best reconstruction quality. These results were obtained by comparing the full-dose image with a low-dose image and an ultra low-dose image. Significance. The convergence speed of the original iterative methods is hampered by the conical geometry and significantly reduced compared to parallel geometries. We promote the pre-conditioned version of PDHG and we propose a pre-conditioned version of the MLEM-TV algorithm. To the best of our knowledge, this is the first time PDHG and convergent MLEM-TV algorithms are evaluated on experimental dental CBCT data, where constraints such as projection truncation and presence of metal have to be jointly overcome.
Polynomial T-depth quantum solvability of noisy binary linear problem: from quantum-sample preparation to main computation
Authors: Song Wooyeong , Lim Youngrong , Jeong Kabgyun , Lee Jinhyoung , Park Jung Jun , Kim M S , Bang Jeongho
Published: September 2022

The noisy binary linear problem (NBLP) is known as a computationally hard problem, and therefore, it offers primitives for post-quantum cryptography. An efficient quantum NBLP algorithm that exhibits a polynomial quantum sample and time complexities has recently been proposed. However, the algorithm requires a large number of samples to be loaded in a highly entangled state and it is unclear whether such a precondition on the quantum speedup can be obtained efficiently. Here, we present a complete analysis of the quantum solvability of the NBLP by considering the entire algorithm process, namely from the preparation of the quantum sample to the main computation. By assuming that the algorithm runs on ‘fault-tolerant’ quantum circuitry, we introduce a reasonable measure of the computational time cost. The measure is defined in terms of the overall number of T gate layers, referred to as T-depth complexity. We show that the cost of solving the NBLP can be polynomial in the problem size, at the expense of an exponentially increasing logical qubits.
Diabatic potential energy surfaces and semiclassical multi-state dynamics for fourteen coupled 3
A′ states of O3
Authors: Varga Zoltan , Shu Yinan , Ning Jiaxin , Truhlar Donald G
Published: September 2022

Dissociation and energy transfer in high-energy collisions of O2 play important roles in simulating thermal energy content and heat flux in flows around hypersonic vehicles. Furthermore, atomic oxygen reactions on the vehicle surface are an important contributor to heat shield erosion. Molecular dynamics modeling is needed to better understand the relevant rate processes. Because it is necessary to model the gas flows in high-temperature shock waves, electronically excited states of O2 and O can be populated, and molecular dynamics simulations should include collisions of electronically excited species and electronically nonadiabatic collisions. This requires potential energy surfaces and state couplings for many energetically accessible electronic states. Here we report a systematic strategy to calculate such surfaces and couplings. We have applied this method to the fourteen lowest-energy potential energy surfaces in the 3
A′ manifold of O3, and we report a neural-network fit to diabatic potential energy matrix (DPEM). We illustrate the use of the resulting DPEM by carrying out semiclassical dynamics calculations of cross sections for excitation of O2 in 3
A′ collisions with O at two collision energies; these dynamics calculations are carried out by the curvature-driven coherent switching with decay of mixing method.
Quantitative corrosion detection of reinforced concrete based on self-magnetic flux leakage and rust spot area
Authors: Chen Lin , Liu Xianlin , Lin Yunfei , Xia Junfeng , Zhao Siyu , Zhang Senhua
Published: September 2022

The internal rebar corrosion of reinforced concrete (RC) structures harm the bearing capacity and durability of structures. Existing methods can measure rebar corrosion but are unsuitable for RC structures. Given this, the self-magnetic flux leakage (SMFL) field of V-shaped rebar corrosion damage was analyzed according to the magnetic dipole model, and the parameter K was proposed to characterize the corrosion degree. Using the naive Bayes algorithm, the SMFL method and the rust spot area analysis method were correlated to propose a rebar corrosion detection method. A corrosion detection experiment was conducted on RC specimens. The results showed that the parameter K was linearly correlated with the maximum cross-sectional rust loss rate η. Using the parameter K to evaluate the rust degree, the accuracy of rebar rust classification was 70%. After introducing the rust spot area ratio S as a supplementary parameter, the accuracy of rebar rust classification increased by 12.5% to 82.5%. This indicates that the proposed method could quantitatively detect the corrosion of the rebars within the concrete.
Age and phenology control photosynthesis and leaf traits in the understory woody species,Rhamnus catharticaandPrunus serotina
Authors: Heskel Mary , Pengra Jean , Kruper Ally , Anderson Michael D , Dosch Jerald J , Goldstein Lianna , Hahn Shannon , Hoffman Sarah
Published: September 2022

Understory plants are often inadequately represented or neglected within analyses of forest ecosystem productivity. Further, the potential impacts of the biological factors of age class and growth form on carbon cycling physiology, and how it may vary across the growing season and amongst species of different native/non-native status, have not been thoroughly considered. Our study examines photosynthesis and associated physical leaf traits in two understory woody species, Rhamnus cathartica, introduced and invasive in North America, and Prunus serotina, a common subcanopy species native to North America. We estimated leaf-level photosynthesis as measured through light and carbon dioxide response curves, dark-adapted chlorophyll fluorescence and leaf traits (leaf mass per area and stomatal density) for each combination of species and age class at plots in the understory of a temperate deciduous research forest in the US Upper Midwest at two time points during the growing season, late spring (late May) and mid-summer (mid-July). Carbon assimilation rates from light response curves (Asat, A400) and fluorescence capacity estimate Fv/Fm all increased between the two measurement points in both species and age class. Estimates of carbon reaction capacity (Vcmax and Jmax) exhibited a different directional response to seasonal development, declining in seedlings of both species and P. serotina trees (~8–37 % reduction in Vcmax, ~9–34 % reduction in Jmax), though increased in trees of R. cathartica (+24 % in Vcmax, +9 % in Jmax). Divergent responses in photosynthetic parameters amongst these factors may be explained by species differences in leaf mass per area and stomatal density, which together are likely influenced by both growth form, canopy position and ontogeny. Overall, we believe our findings suggest complex, varied influences on photosynthesis that indicate environmental and biological plasticity which may contribute to the historic and continued expansion of R. cathartica in the US Upper Midwest region.
BioGPT: generative pre-trained transformer for biomedical text generation and mining
Authors: Luo Renqian , Sun Liai , Xia Yingce , Qin Tao , Zhang Sheng , Poon Hoifung , Liu Tie-Yan
Published: September 2022

Pre-trained language models have attracted increasing attention in the biomedical domain, inspired by their great success in the general natural language domain. Among the two main branches of pre-trained language models in the general language domain, i.e. BERT (and its variants) and GPT (and its variants), the first one has been extensively studied in the biomedical domain, such as BioBERT and PubMedBERT. While they have achieved great success on a variety of discriminative downstream biomedical tasks, the lack of generation ability constrains their application scope. In this paper, we propose BioGPT, a domain-specific generative Transformer language model pre-trained on large-scale biomedical literature. We evaluate BioGPT on six biomedical natural language processing tasks and demonstrate that our model outperforms previous models on most tasks. Especially, we get 44.98%, 38.42% and 40.76% F1 score on BC5CDR, KD-DTI and DDI end-to-end relation extraction tasks, respectively, and 78.2% accuracy on PubMedQA, creating a new record. Our case study on text generation further demonstrates the advantage of BioGPT on biomedical literature to generate fluent descriptions for biomedical terms.
LION: an integrated R package for effective prediction of ncRNA–protein interaction
Authors: Han Siyu , Yang Xiao , Sun Hang , Yang Hu , Zhang Qi , Peng Cheng , Fang Wensi , Li Ying
Published: September 2022

Understanding ncRNA–protein interaction is of critical importance to unveil ncRNAs’ functions. Here, we propose an integrated package LION which comprises a new method for predicting ncRNA/lncRNA–protein interaction as well as a comprehensive strategy to meet the requirement of customisable prediction. Experimental results demonstrate that our method outperforms its competitors on multiple benchmark datasets. LION can also improve the performance of some widely used tools and build adaptable models for species- and tissue-specific prediction. We expect that LION will be a powerful and efficient tool for the prediction and analysis of ncRNA/lncRNA–protein interaction. The R Package LION is available on GitHub at https://github.com/HAN-Siyu/LION/.
Reduced hippocampal-cortical connectivity during memory suppression predicts the ability to forget unwanted memories
Authors: Yan Yuchi , Hulbert Justin C , Zhuang Kaixiang , Liu Wei , Wei Dongtao , Qiu Jiang , Anderson Michael C , Yang Wenjing
Published: September 2022

The ability to suppress unwelcome memories is important for productivity and well-being. Successful memory suppression is associated with hippocampal deactivations and a concomitant disruption of this region’s functionality. Much of the previous neuroimaging literature exploring such suppression-related hippocampal modulations has focused on the region’s negative coupling with the prefrontal cortex. Task-based changes in functional connectivity between the hippocampus and other brain regions still need further exploration. In the present study, we utilize psychophysiological interactions and seed connectome-based predictive modeling to investigate the relationship between the hippocampus and the rest of the brain as 134 participants attempted to suppress unwanted memories during the Think/No-Think task. The results show that during retrieval suppression, the right hippocampus exhibited decreased functional connectivity with visual cortical areas (lingual and cuneus gyrus), left nucleus accumbens and the brain-stem that predicted superior forgetting of unwanted memories on later memory tests. Validation tests verified that prediction performance was not an artifact of head motion or prediction method and that the negative features remained consistent across different brain parcellations. These findings suggest that systemic memory suppression involves more than the modulation of hippocampal activity—it alters functional connectivity patterns between the hippocampus and visual cortex, leading to successful forgetting.
Learning whom to cooperate with: neurocomputational mechanisms for choosing cooperative partners
Authors: Jin Tao , Zhang Shen , Lockwood Patricia , Vilares Iris , Wu Haiyan , Liu Chao , Ma Yina
Published: September 2022

Cooperation is fundamental for survival and a functioning society. With substantial individual variability in cooperativeness, we must learn whom to cooperate with, and often make these decisions on behalf of others. Understanding how people learn about the cooperativeness of others, and the neurocomputational mechanisms supporting this learning, is therefore essential. During functional magnetic resonance imaging scanning, participants completed a novel cooperation-partner-choice task where they learned to choose between cooperative and uncooperative partners through trial-and-error both for themselves and vicariously for another person. Interestingly, when choosing for themselves, participants made faster and more exploitative choices than when choosing for another person. Activity in the ventral striatum preferentially responded to prediction errors (PEs) during self-learning, whereas activity in the perigenual anterior cingulate cortex (ACC) signaled both personal and vicarious PEs. Multivariate pattern analyses showed distinct coding of personal and vicarious choice-making and outcome processing in the temporoparietal junction (TPJ), dorsal ACC, and striatum. Moreover, in right TPJ the activity pattern that differentiated self and other outcomes was associated with individual differences in exploitation tendency. We reveal neurocomputational mechanisms supporting cooperative learning and show that this learning is reflected in trial-by-trial univariate signals and multivariate patterns that can distinguish personal and vicarious choices.
The Perceived Convincingness Model: why and under what conditions processing fluency and emotions are valid indicators of a message’s perceived convincingness
Authors: Hoeken Hans , Fikkers Karin , Eerland Anita , Holleman Bregje , van Berkum Jos , Pander Maat Henk
Published: September 2022

Persuasive messages aim to influence people’s behavior. Arguments in these messages typically refer to the positive consequences of the advocated behavior or the negative consequences of failing to do so. It has been claimed that people automatically generate a judgment about the message’s convincingness. We present the Perceived Convincingness Model (PCM) to explain how people generate this judgment based upon the fluency with which they process the message and the intensity of the resulting emotions. When these experiences are elicited by the processing of the message’s arguments, they can be crude, yet relevant indicators of the extent to which the arguments meet the normative criteria of acceptability, relevance, and sufficiency. Thus, under some conditions, trusting one’s feelings may be a rational strategy when deciding to heed an advice or not.
17. EFFECT OF BILE ACID AND PANCREATIC JUICE IN REFLUX ESOPHAGITIS AFTER TOTAL GASTRECTOMY IN RAT MODEL
Authors: Hashimoto Naoki
Published: September 2022

Esophagitis after total gastrectomy has been associated with the reflux of duodenal content into the esophagus.

This study is to determine which fraction of the duodenum content reflux, pancreatic juice or bile acids contributes to the development of reflux esophagitis.

8 week Wistar Rats were used.

1. Reflux of Pancreatic juice and Bile(TG):End-to-end esophago-duodenostomy with total gastrectomy (n = 8)

2. Reflux of Pancreatic Juice (TG + P):End-to-end esophago-duodenostomy with total gastrectomy. Then, a bypass operation of the upper bile duct was made 25 cm below the esophagoduodenostomy anastomosis. Choledocho-jejunostomy was performed. (n = 6)

3. Reflux of Bile (TG + B) (n = 4):Roux-en-Y esophagojejunostomy with total gastrectomy. The bile duct was then divided and reimplanted into the proximal portion of the Roux limb, preceding the esophagojejunostomy to produce biliary reflux.

Three weeks after, all rats were euthanized and the esophagus was evaluated histologically.

1. Macroscopy: In TG rats, the esophageal wall was thickened and covered with whitish nodular patches. The gross appearance of the esophagus from TG + P and TG + B group showed only scattered erosions. The ulcer score in TG + P and TG + B were significantly lowered compared to TG. 2. Microscopy: TG group developed large and long longitudinal ulcers. The inflammatory cell infiltration scores and hyperplasia scores were significantly decreased in the TG + B and TG + P group compared to TG group.

The reflux of pancreatic juice alone and bile acid alone are not significant development of reflux esophagitis. Reflux of combined of bile acid and pancreatic juice to esophagus caused sever reflux esophagitis.
18. REFLUX OF DUODENAL CONTENTS INDUCES ESOPHAGEAL CARCINOGENESIS (SCC, ADC)
Authors: Hashimoto Naoki
Published: September 2022

The incidence of esophageal cancer patients who have undergone distal gastrectomy is increasing recently. Distal gastrectomy is a good model for studying the clinical effects of duodenal content reflux.

It is known that reflux of duodenal contents can induce mucosal injury, stimulate cell proliferation, and promote tumorigenesis. We examined the expression of COX2 and P53 in rat esophageal lesions induced by duodenal contents reflux after total gasytrectomy.

Thirty 8 week old male wistar rats were exposed to duodenal content esophageal reflux. All animal underwent an esophagoduodenal anastomosis(EDA) with total gastrectomy in order to produce chronic esophagitis. Ten rats were the sham (Control). They were sacrified at the 40th week. Their esophagi were examined for HE, COX2,P53 and Proliferating cell nuclear antigen (PCNA).

After 40 weeks of reflux, dysplasia(100%), squamous cell carcinoma(SCC)(40%) and adenocarcinoma (ADC) (30%)were found. PCNA Labeling index was higher in dysplastic and cancer tissue than that of normal. Overexpression of COX2 were shown in ADC and SCC. Wild type p53 accumulation were found in ADC, not in SCC. Moreover, SCC developed in places distant from the anastomosis compared to ADC. As compared with ADC, SCC is less frequently inflammatory.

This means that histological features may depend on the volume of reflux contents; small amounts of reflux causes SCC and a large volume of reflux causes ADC.

Reflux of duodenal contents into the esophagus led to ADC and SCC in rat. Small amounts of reflux causes SCC and a large volume of reflux causes ADC.

COX2 may play an important role in esophageal cancer by duodenal content reflux. Our present results suggest an association between wild type P53 accumulation and COX2 expression in ADC, with no such relation seen in SCC.
137. THE COMPARISON OF SHORT-TERM OUTCOMES BETWEEN NEOADJUVANT CHEMOTHERAPY COMBINED WITH IMMUNOTHERAPY AND NEOADJUVANT CHEMORADIOTHERAPY FOR ESOPHAGEAL SQUAMOUS CANCER
Authors: Xiao Xin , Yuan Yong
Published: September 2022

To evaluate the short-term outcomes of neoadjuvant chemotherapy combined with immunotherapy followed by esophagectomy for locally advanced esophageal squamous cell carcinoma.

Patients receiving neoadjuvant chemotherapy combined with immunotherapy (NACI group) or chemoradiotherapy (NACR group) at our center between September 2019 and September 2021 were identified. The primary outcomes were tumor regression score (TRS), pathological complete regression (pCR), overall survival (OS), progression-free survival (PFS) and pathological downstaging. Secondary outcomes were toxic effects and postoperative complications. The propensity score matching for enrolled patients was performed.

Data of 149 patients were analyzed. All included patients received minimally invasive esophagectomy, with only 3 conversion to open surgery. With regard toTRS, 25 (45.5%), 61 (64.9%) patients were scored 0 and 1 in the NACI and NACR groups, respectively (p = 0.020). Of note, 17 (30.9%) patients in the NACI group achieved pCR (ypT0N0), while 48 (51.1%) patients in NACR group achieved pCR (P = 0.026). Neoadjuvant chemoradiotherapy was associated with higher risk of postoperative pneumonia (p = 0.034). The 1-year cumulative progression-free survival rate was 85.4% and 75.4% in the NACI and NACR groups respectively (p = 0.147).

We found that neoadjuvant immunotherapy combined with chemotherapy compared with neoadjuvant chemoradiotherapy was associated with lower pneumonia rate and was safe and feasible for locally advanced ESCC. However, the tumor regression score and the pathological complete response rate of patients treated with neoadjuvant immunotherapy was lower than those of patients treated with neoadjuvant chemoradiotherapy. The short-term follow-up results were comparable between two treatment modalities.
138. TIMELY VERSUS DELAYED ESOPHAGECTOMY AFTER NEOADJUVANT CHEMORADIOTHERAPY FOR LOCALLY ADVANCED ESOPHAGEAL SQUAMOUS CANCER
Authors: Xiao Xin , Yuan Yong
Published: September 2022

The optimal time interval from neoadjuvant therapy to surgery for esophageal cancer still remains unclear and controversial. Our aims were to investigate if prolonged time to surgery would have an impact on pathological complete response (pCR) rates and postoperative complications, and affect the survival for locally advanced esophageal squamous cancer (ESCC).

Patients with locally advanced ESCC receiving neoadjuvant chemoradiotherapy followed by esophagectomy between June 2017 and December 2020 were prospectively enrolled and retrospectively analyzed. Patients were divided into two groups, timely and delayed surgery groups, namely, group A (< 10 weeks) and group B (≥ 10 weeks). We further classified the patients according to interval quartiles and 3-week groups. We measured the tumor regression score (TRS), pathological complete regression (pCR), clinical complete regression (cCR), overall survival (OS), progression-free survival (PFS) and postoperative complications as the analytical outcomes for this study.

A total of 40 patients (34.5%) in the timely surgery group (n = 116) and 54 patients (50.0%) in the delayed surgery group (n = 108) achieved pCR (P = 0.019). The postoperative complications and survival for two groups were similar. However, for patients with a non-cCR, delayed surgery was associated with poor survival (P = 0.035) and cancer progression (P = 0.036). For the second step of analysis, using linear-by-linear association chi-square test, the pCR rates were significantly difference across 4 groups and were increased along with time interval (P = 0.006). Results for 3-week intervals were similar (P = 0.009).

Patients with prolonged time interval (up to 12 weeks) from neoadjuvant chemoradiation to surgery have higher pCR rates without an impact on operative morbidity. For patients who have a non-cCR to neoadjuvant chemoradiation, delayed surgery was associated with poor survival and surgery should be performed within 10 weeks after neoadjuvant chemoradiation.
176. THE SURGICAL OUTCOMES OF LAPAROSCOPIC HELLER CARDIOMYOTOMY AND DOR FUNDOPLICATION FOR ACHALASIA
Authors: Lim Kheng Tian
Published: September 2022

Esophageal cardiomyotomy is the main component of treatment in achalasia which can be performed endoscopically or by surgery. Laparoscopic esophageal cardiomyotomy for achalasia is associated with reduced early postoperative morbidity compared to open surgery whilst laparoscopic anterior fundoplication is associated with reduced postoperative reflux symptoms. Proton Pump Inhibitor (PPI) is usually prescribed for postoperative acid reflux symptoms. The outcomes of laparoscopic Heller cardiomytomy and Dor fundoplication (LHCDF) from our unit were analyzed.

Consecutive cases of achalasia who underwent LHCDF were identified from electronic medical records from June 2016 to December 2021. The preoperative assessment included esophagogastroduodenoscopy (EGD), oral contrast swallow (OCS), esophageal high-resolution manometry (HRM) and occasionally a computed tomography scan. Objective symptoms evaluation using Eckardt score was performed before and after surgery. Long myotomy was performed with 7 cm on esophageal and 2 cm on gastric side followed by 3-stitches on each side of Dor fundoplication. Intraoperative EGD and postoperative OCS was routinely performed. The surgical outcomes of LHCDF were analyzed.

There were 11 cases of LHCDF with the mean age of 50 ± 5 years and M:F ratio 4:7. HRM confirmed 1 Type-I and 8 Type-II achalasia. The mean preoperative Eckardt score was 7.2 ± 0.5 and postoperative score of 0.5 ± 0.2. The mean duration of operation was 206 ± 7 minutes. There were no surgery-related complications, readmission, or mortality. The mean length of stay was 3 ± 0.5 days. Postoperative PPI use for acid reflux symptoms was 19% (n = 2). EGD at 1 year showed 1 esophagitis. The mean duration of clinic follow up was 24.6 ± 5.4 months.

LHCDF achieved good symptoms relief and surgical outcomes in patients with symptomatic achalasia. In this small cohort and short-term follow up, the majority of post-LHCDF patients did not require PPI for acid reflux symptoms and none required endoscopic or surgical reintervention.
225. TREATMENT OF ANASTOMOTIC LEAK AFTER ESOPHAGECTOMY (TENTACLE– ESOPHAGUS) STUDY: EFFICACY OF DIFFERENT INITIAL TREATMENT STRATEGIES FOR ANASTOMOTIC LEAK
Authors: Ubels Sander , Verstegen Moniek , Bouwense Stefan , Hannink Gerjon , Siersema Peter , Klarenbeek Bastiaan , van Workum Frans , Rosman Camiel ,   on Behalf of the TENTACLE - Esophagus Collaborative Group
Published: September 2022

Anastomotic leak (AL) is a common and severe complication after esophagectomy. The presentation of AL is diverse and various treatments are available. However, it is unknown which treatment strategy for which type of leak is most effective. We aimed to investigate the effectiveness of different primary treatments of AL after esophagectomy.

TENTACLE—Esophagus is an international retrospective cohort study in 71 centers from 20 countries, which included patients with anastomotic leak after esophagectomy between 2011 and 2019. Detailed data were collected regarding leak characteristics and treatment. Primary outcome was 90-day mortality. Different leak types were defined, i.e., local symptoms (i.e., no intrathoracic fluid collections and well-perfused conduit), intrathoracic fluid collections and conduit ischemia/necrosis. Efficacy of different primary treatment strategies were assessed for these leak types, adjusted for case-mix and leak severity. The full study protocol is accessible at www.tentaclestudy.com.

In total, 1509 patients with AL were included and overall 90-day mortality was 11.7%. Of all patients, 482 patients had only local symptoms, 725 patients had intrathoracic fluid collections and 148 patients had conduit ischemia/necrosis. Primary treatment strategies included supportive treatment only (n = 335), drainage (n = 590), defect closure (n = 67), drainage & defect closure (n = 289) and surgical resection of the conduit & esophageal diversion (n = 57). The efficacy of different primary leak treatment strategies is currently being assessed. Results on the efficacy of primary treatment strategies for AL will be ready for presentation at the ISDE meeting.

This is the largest study on effectiveness of AL treatments. The final results on efficacy of primary leak treatments will be available for presentation at the ISDE meeting in Tokyo and can offer guidance in clinical practice to determine the preferred primary treatment strategy in patients with anastomotic leak after esophagectomy.
360. DIAGNOSIS OF RECURRENT LARYNGEAL NERVE PARALYSIS BY EVALUATING MOVEMENT OF THE VOCAL CORDS USING ULTRASONOGRAPHY AFTER MINIMALLY INVASIVE ESOPHAGECTOMY
Authors: Leng Xuefeng , Teng Xiangnan , Xu Shanling , Peng Lin , Xiao WenGuang , Fang Qiang , Han Yongtao , Zhu Yi
Published: September 2022

Development of thoracoscopic surgical skills and concepts in minimally invasive esophagectomy (MIE) and robotic-assisted (MIE) have provided us with a more wider anatomical understanding of lymphadenectomy and the relationship between lymph node dissection and recurrent laryngeal nerve paralysis (RLNP). However, RLNP correlates to postoperative complications even in prognosis. Early warning and novel diagnosis are urgent in the management of esophageal cancer patients.

Taking a novel approach to researching the diagnosis of RLNP, we evaluated movement of the vocal cords and arytenoid cartilages using ultrasonography in patients who underwent thoracoscopic esophagectomy after extubating of trachea cannula at department of critical care medicine. Further ultrasonography combined endoscopy evaluation and verification were performed on day 5–7 before hospital discharge.

RLNP occurred in 4 of the 20 patients’ cohort (20%). All of 20 patients were finished ultrasonography combined endoscopy evaluation. The diagnostic accuracy of RLNP by ultrasonography compared to endoscopy had a sensitivity of 100.0% (4/4), a specificity of 87.5% (14/16). The positive predictive value was 66.7% (4/6), negative predictive value was 100.0% (14/14), a false positive rate of 33.3% (2/6), and a false negative rate of 0% (0/14).

Ultrasonography is a quite non-invasive and effective measure to diagnose and evaluate RLNP after esophagectomy compared to traditional examination of endoscopy. It also has a perspective future in evaluation for the recovery status of RLNP.
458. Multimodal analgesia after oesophagectomy provides clinically equivalent pain control for open and thoracoscopic approaches
Authors: Chung Jordan Ng Cheong , Barry James , Chmelo Jakub , Navidi Maziar , Phillips Alexander
Published: September 2022

Adequate pain control is an important consideration to ensure patients can mobilise after surgery and to reduce pulmonary complications. This is frequently provided by a thoracic epidural, however there has been increasing use of multimodal analgesia. Minimally invasive approaches in esophagectomy may also reduce post-operative pain. The aim of this study was to compare pain control in patients after Ivor Lewis esophagectomy with thoracoscopic (TE) vs open approach using multimodal analgesia.

Consecutive patients undergoing thoracoscopic or open esophagectomy for cancer between January 2015 and December 2019 were evaluated. All patients received multimodal analgesia (intrathecal diamorphine, paravertebral and rectus sheath catheters). Pain scores (at rest and on movement, graded from 0 to 10) were collected and compared between two cohorts. Length of stay and complications were also compared between the two groups.

This study included 161 patients; 114 (70.8%) underwent an open esophagectomy and 47 (29.2%) underwent a thoracoscopic chest phase. Mean pain scores were significantly lower for TE only on postoperative days (POD) 0 on movement (open 2.81 versus TE 1.50, p = 0.026) and POD 3 at rest (open 1.00 versus TE 0.60, p = 0.030). Postoperative stay was comparable between groups (9 versus 8 days). There was no significant difference in the overall complication rate (64.0% versus 57.4%, p = 0.433), pulmonary complications (27.7% versus 35.1% p = 0.461) and 30-day mortality (2.6% versus 0%, p = 0.262).

These results may suggest that a minimally invasive thoracoscopic approach does not provide additional analgesic benefit in comparison to open approach when multimodal analgesia is used. A clinically meaningful difference (score difference 0.9-1.6) was achieved only on POD 0. Importantly, in this cohort the open approach was not associated with inferior short-term postoperative outcomes. Future randomised controlled trials comparing minimally invasive techniques should consider employing multimodal analgesia in their design.
465. RELATIONSHIP BETWEEN THE PERIOPERATIVE NUTRITION, INFLAMMATION AND PROGNOSIS IN RESECTABLE ESOPHAGEAL CANCER PATIENTS, POSSIBLE SIGNIFICANCE OF NUTRITIONAL INTERVENTION
Authors: Fujiwara Yoshinori , Endo Shunji , Higashida Masaharu , Kubota Hisako , Yoshimatsu Kazuhiko , Ueno Tomio
Published: September 2022

Inversed relationship between inflammatory response and nutrition were reported, and preoperative mGPS score has been proposed as a useful prognostic biomarkers in several malignancies. It has been reported that the postoperative inflammatory responses may cause cancer recurrence and metastasis. In the present study, we investigated the treatment strategy from perioperative inflammatory reaction and nutritional status in patients with resectable esophageal cancer.

110 esophageal cancer patients (Squamous cell carcinoma, Stage I / II / III / IV: 44/17/39/20) were evaluated. The preoperative mGPS score was evaluated on a scale of 0 to 2. The cut-off value of albumin, CRP were 3.5g/dl, 0.14mg/dl, respectively. As the postoperative CRP, CRPmax and the area under the CRP curve (CRP (7), CRP (14)) for 7 days and 14 days after the operation, and ROC curve was used to set at optimal cut-off value of these parameters. Outcome was RFS (Recurrence Free Survival) and identified prognostic factors were determined by Cox multivariate analysis.

1, Preoperative albumin value was significantly lower in high CRP (> 0.14mg / dl) (p <0.05)). 2, Preoperative mGPS score 0 was better RFS than in the other groups(p<0.05).3, Univariate analysis showed that mGPS, albumin, and CRP were prognostic factors for RFS, but Cox analysis showed mGPS was not prognostic factor. 4, The cut-off value of CRP (7) and CRP (14) were 59.9, 115.3, respectively. CRP (7) was prognostic factor for RFS in univariate analysis, but Cox analysis showed that only pStage and tumor locations were significant prognostic factors, high CRP (7) was tended to be poor prognostic (p = 0.089).

Clinical Stages, tumor locations were most important prognostic factors in resectable esophageal cancer patients. However, preoperative nutritional intervention may improve the prognosis of patients with esophageal cancer if preoperative CRP values can be suppressed. Suppressing the inflammatory reaction one week after surgery may improve the prognosis of patients with esophageal cancer.
520. EFFICACY AND SAFETY OF NEOADJUVANT CHEMOTHERAPY AND IMMUNOTHERAPY IN LOCALLY RESECTABLE ADVANCED ESOPHAGEAL SQUAMOUS CELL CARCINOMA
Authors: Gong Taiqian , Gong Taiqian , Song Weian , Lu Jing , Liu Junqiang , Fan Boshi , Zhao Jiahua , Chen Siyu
Published: September 2022

Compared with neoadjuvant chemotherapy, concurrent chemoradiotherapy can significantly increase pCR rate and improve overall survival of Locally Advanced ESCC. However, the major pattern of failure is distant metastasis, and the increased risk of adverse events and surgery. Adding PD-1 inhibitor to the chemotherapy have shown significant clinical benefits and become the standard of care for first-line treatment of ESCC. We investigate the efficacy and safety of neoadjuvant PD-1 blockade combined with chemotherapy in real world.

We performed a retrospective, single institution review of all resectable locally advanced ESCC patients who received neoadjuvant sintilimab combined with chemotherapy and completed surgery in the sixth medical center of PLA general hospital from December 2019 to February 2022. The primary outcome was pCR rate in both the primary tumor and lymph nodes. Secondary outcomes were R0 resection rate, MPR rate, tumor downstaging rate, surgical complications, and treatment-related adverse events (TRAEs).

37 Patients aged between 47 to 76 years old (median age, 62) were collected. 3(8.1%) were diagnosed with stage II ESCC, 30(81.1%) with stage III, and 7(18.9%) with stage IVA (AJCC 8th). 30(81.1%) were male. 31 patients received 2 cycles and 6 patients received 3 cycles. 5(13.5%) patients obtained pCR. 7(18.9%) patients obtained pCR in primary tumor. 36(97.3%) patients obtained R0 resection. MPR (PCR included) was achieved in 18 (48.6%) patients. 28(75.7%) patients achieved clinical downstaging, and 64.9 (%) achieved pathological downstaging. Grade 3-4 TRAEs occurred in 7(18.9%) patients, and grade 3-4 surgical complications occurred in 1(2.7%) patient.

These real-world data revealed that neoadjuvant sintilimab plus chemotherapy could provide benefits with good tolerability for resectable locally advanced ESCC, and warrants further exploration in prospective clinical studies.