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In this work, the effect of extrusion process on the mechanical properties and the stress corrosion cracking (SCC) resistance of 7N01 aluminum alloys were systematically investigated by tensile testing, slow strain rate testing (SSRT), electrochemical experiment, scanning electron microscopy (SEM), electron backscattered diffraction (EBSD), and transmission electron microscope (TEM) observation, respectively. The results showed that with the increase of extrusion temperature, the SCC resistances of the alloys deteriorated, and this tendency was also proved by the electrochemical experiments including polarization curves and EIS results. The Microstructure observation results revealed that recrystallization played an important role on the SCC resistances of the alloys: the new recrystallization grain boundaries with higher grain boundary energy and wider PFZ could magnify the difference of electrochemical property between grain boundary area and the grain interior, thus raising the stress corrosion crack sensitivity of the alloys.

The A7N01-T5 aluminum alloy plates with the thickness of 12 mm were welded with the ER5356 and ER5087 welding wires, respectively, by the method of Metal Inert Gas (MIG) welding. The mechanical properties and microstructures of the welded joints were investigated by micro-hardness measurement, tensile test, energy dispersive spectroscopy (EDS), electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM). The results showed that the tensile strength and elongation of 7N01/5087 welded joint (the 7N01 aluminum alloy plate welded with ER5087 wire) were greater than those of 7N01/5356 welded joint (the 7N01 aluminum alloy plate welded with ER5356 wires), respectively. The high strength and the good elongation of 7N01/5087 welded joint were mainly attributed to the microstructure refinement in the weld zone through adding Zr element to promote the nucleation of Al grains around the Al3Zr sites.

Le Hu,1– 3 Jia Wang,1– 3 Ye Zhang,1– 3 Junyu Wang,1– 3 Bing Wei1– 3 1Emergency Medical Center, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, People’s Republic of China; 2Beijing Key Laboratory of Cardiopulmonary Cerebral Resuscitation, Beijing, People’s Republic of China; 3Clinical Center for Medicine in Acute Infection, Capital Medical University, Beijing, People’s Republic of ChinaCorrespondence: Bing Wei; Junyu Wang, Email dr_weibing@126.com; wangjunyu_cyyy@126.comObjective: To evaluate and predict adverse outcomes associated with serum Syndecan-1 (SYN-1) levels in patients with early sepsis, and to explore the prognostic risk factors in sepsis and septic shock.Methods: This retrospective single-center observational study included 168 sepsis patients admitted to the Emergency Department of Beijing Chao-Yang Hospital Shijingshan Branch, Capital Medical University, from October 2020 to October 2021. Patients were categorized into sepsis (n=114) and septic shock (n=54) groups based on Sepsis 3.0 criteria. They were further divided into survival (n=128) and death (n=40) groups. Comparative analyses included general demographics and laboratory findings (SYN-1, lactic acid [LAC], procalcitonin [PCT], C-reactive protein [CRP]) within 3 hours of admission, as well as Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores. Statistical methods included receiver operating characteristic (ROC) curve analysis, correlation analysis, and logistic regression.Results: Serum SYN-1 levels were significantly higher in the septic shock group (138.89± 9.26) compared to the sepsis group (102.89± 8.97) (P < 0.05). SYN-1 levels were also significantly higher in the death group (150.19± 7.65) compared to the survival group (103.301± 86.59) (P < 0.05). The area under the ROC curves for SYN-1, LAC, and APACHE II scores in predicting 28-day mortality were 0.668, 0.641, and 0.666, respectively. SYN-1 showed a positive correlation with SOFA scores (correlation coefficient=0.228). SYN-1, APACHE II score, and LAC were identified as independent risk factors for 28-day mortality in sepsis patients.Conclusion: SYN-1 demonstrates high sensitivity and specificity in early prediction of poor outcomes in sepsis patients. SYN-1, APACHE II score, and LAC serve as independent risk factors for 28-day mortality in sepsis patients.Keywords: Syndecan-1, sepsis, septic shock

A crucial step of the two commonly used geostatistical methods for modeling heterogeneous reservoirs : the sequential indicator simulation and the truncated Gaussian simulation is the estimation of the lithofacies local proportion (or probability density) functions. Well-test derived permeabilities show good correlation with lithofacies proportions around wells. Integrating well and well-test data in estimating lithofacies proportions could permit the building of more realistic models of reservoir heterogeneity. However this integration is difficult because of the different natures and measurement scales of these two types of data. This paper presents a two step approach to integrating well and well-test data into heterogeneous reservoir modeling. First lithofacies proportions in well-test investigation areas are estimated using a new kriging algorithm called KISCA. KISCA consists in kriging jointly the proportions of all lithofacies in a well-test investigation area so that the corresponding well-test derived permeability is respected through a weighted power averaging of lithofacies permeabilities. For multiple well-tests, an iterative process is used in KISCA to account for their interaction. After this, the estimated proportions are combined with lithofacies indicators at wells for estimating proportion (or probability density) functions over the entire reservoir field using a classical kriging method. Some numerical examples were considered to test the proposed method for estimating lithofacies proportions. In addition, a synthetic lithofacies reservoir model was generated and a well-test simulation was performed. The comparison between the experimental and estimated proportions in the well-test investigation area demonstrates the validity of the proposed method. La méthode de simulation gaussienne seuillée et la méthode de simulation séquentielle d'indicatrices sont aujourd'hui couramment utilisées pour générer des modèles lithologiques de réservoirs. Ces méthodes consistent à estimer dans un premier temps les proportions (ou probabilités) de faciès et ensuite, à construire des modèles en faciès par troncature d'une fonction aléatoire gaussienne selon les proportions de faciès (ou par tirage au sort selon les probabilités de faciès). La validité d'un modèle ainsi construit dépend fortement de l'exactitude des proportions (ou probabilités) de faciès estimées. En cas de données de puits peu nombreuses, la prise en compte d'autres sources d'informations (connaissance géologique, sismique, essais de puits et historique de production) peut améliorer l'estimation des proportions. Dans ce travail, on s'intéresse, en particulier, à l'intégration des données de puits et d'essais de puits dans l'estimation des proportions (ou probabilités) de faciès. Une méthode, appelée krigeage itératif sous contraintes d'agrégation (KISCA), est proposée pour estimer les proportions de faciès dans l'aire d'investigation des essais de puits. KISCA consiste à krigerconjointement les proportions de tous les faciès dans une aire d'investigation de façon à ce que la perméabilité apparente de l'essai de puits soit respectée via une formule de moyenne en puissance des perméabilités absolues des faciès. En cas d'essais de puits multiples, une procédure itérative est utilisée afin de prendre en compte leur interaction. De simples exemples numériques sont présentés pour illustrer les comportements de la méthode proposée. Pour tester la validité de cette méthode, un réservoir synthétique en faciès est construit et une simulation d'essai de puits est effectuée. La comparaison entre les proportions expérimentales et estimées montre la validité de la méthode proposée. La stabilité numérique et le temps de calcul de cette méthode est comparable au krigeage classique. Les corrélations entre faciès sont partiellement prises en compte par l'introduction des contraintes d'essais de puits et la contrainte de normalité dans le système de krigeage. Les proportions de faciès dans les aires d'investigation des essais de puits peuvent être plus facilement intégrées dans un modèle lithologique construit par simulation gaussienne seuillée ou par simulation séquentielle d'indicatrices.

Perpendicular magnetic anisotropy (PMA) in magnetic thin films has attracted much attention due to its potential applications in spintronics devices. Here, we report the continuous strain-mediated PMA in epitaxial (111) CoFe 2 O 4 (CFO) thin films grown on (0001) LiTaO 3 substrates. A large variation in lattice strain (∼ 0.9 %) in a continuous way is realized in the CFO thin films by changing substrate temperature during deposition due to the difference in the thermal expansion coefficient between CFO and LiTaO 3. As a result, the PMA of the (111) CFO thin films can be continuously mediated by the strain with uniaxial magnetic anisotropy energy in the range of 0.12 - 14.69 × 10 6 erg/cm 3. Furthermore, the strain as well as the consequent PMA in the (111) CFO thin films can be maintained within the thickness of 25–205 nm, which is consistent with the scenario of the magnetoelastic effect. Our results reveal that the CFO/LiTaO 3 system can be regarded as an ideal platform to realize robust PMA and its continuous strain tuning in the (111) CFO thin films by virtue of strain-induced magnetic anisotropy. [ABSTRACT FROM AUTHOR]

Yu Wang,1,&ast; Hanning Zha,1,&ast; Xiang Fang,2 Tianjiao Shen,1 Kunyun Pan,1 Jianping Zhang,1 Keqiang He,1 Sheng Wang,1 Liguo Hu1 1Department of Anesthesiology, The First Affiliated Hospital of USTC (Anhui Provincial Hospital), Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, People’s Republic of China; 2Department of Anesthesiology, Hefei BOE Hospital, Hefei, Anhui, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Sheng Wang; Liguo Hu, Email iamsheng2020@ustc.edu.cn; hulg@163.comObjective: The dose selection of ropivacaine for spinal anesthesia in clinical work mainly depends on the experience of the anesthesiologist. In this study, a prospective and modified up-down sequential allocation design was used to provide the optimal dose selection of ropivacaine for spinal anesthesia.Patients and methods: This study was divided into two stages, and a total of 164 elderly patients with elective hip fractures were included. In stage I, the dose of ropivacaine was selected using the up-down sequential method of height correction, and the 50% effective dose (ED50) and 95% effective dose (ED95) were obtained. A nomogram for predicting satisfactory anesthesia and a formula for predicting the optimal dose was also given in this stage. In stage II, the dose of ropivacaine was calculated by using the optimal dose prediction formula, so as to evaluate the efficacy and safety of the model.Results: The ED50 and ED95 of the stage I were 7.036 mg (95%CI 6.549– 7.585 mg) and 8.709 mg (95%CI 7.902– 14.275 mg), respectively. And provided a nomogram predicting satisfactory anesthesia with a C-index of 0.847 (95%CI 0.774– 0.92). The optimal dose prediction formula of ropivacaine was calculated, including variables for age, gender, height, and weight. This formula was found to be 90% efficient. It is worth mentioning that the incidence of direct transfer to the ward in the two stages was as high as 86.84% and 93.33%, respectively, and no patients were transferred to the ICU in stage II.Conclusion: The ED50 and ED95 of ropivacaine were 7.036 mg and 8.709 mg, respectively, and the nomograms are sufficiently accurate to predict satisfactory anesthesia. Beyond that, the dose prediction equation provided in this study has high efficacy and safety, and can guide the dose selection of spinal anesthesia in elderly patients with hip fracture in clinical practice.Clinical trials registration: ChiCTR2100046982Keywords: ropivacaine, dose selection, elder, spinal anesthesia, Hip fracture, sequential design

Yi-Lun Ge,1,&ast; Si-Yi Gong,1,&ast; Pu-Zhi Wang,1 Jia-Hui Yan,1 Wen Li,1 Jin-Ru Zhang,1 Hong Jin,1 Sheng Zhuang,1 Lei Hu,2 Chang-Wei Ding,2 Ya-Ping Yang,1 Fen Wang,3 Dan Li,4 Jing Chen,1 Cheng-Jie Mao,1,4 Ying-Chun Zhang,2 Kai Li,1 Chun-Feng Liu1,3,4 1Department of Neurology, the Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, People’s Republic of China; 2Department of Ultrasound, the Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, People’s Republic of China; 3Institute of Neuroscience, Soochow University, Suzhou, Jiangsu, People’s Republic of China; 4Department of Neurology, Suqian First Hospital, Suqian, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Kai Li, Department of Neurology, the Second Affiliated Hospital of Soochow University, No. 1055 Sanxiang Road, Suzhou, Jiangsu, 215004, People’s Republic of China, Tel +86-512-6778-4179, Fax +86-512-6828-4303, Email liskai@126.comPurpose: Cognitive impairment (CI) is a common but debilitating non-motor symptom in Parkinson’s disease (PD). Although cerebrovascular functions are related to cognitive performance in healthy individuals, such a relation in PD remains elusive. This study aims to assess the association between cerebrovascular function and cognitive performance in PD individuals.Patients and Methods: Two-hundred-and-one PD individuals were retrospectively included. They were subsequently divided into two groups: PD with normal cognition (PD-NC) and PD with CI (PD-CI). Cerebral hemodynamic characteristics of the middle cerebral arteries were assessed by transcranial ultrasound. The association between scores in each cognitive domain and cerebral hemodynamic parameters was further analyzed using regression analyses. Additionally, a binary logistic regression model with backward stepwise procedure was applied to build the model for discriminating CI in PD individuals. An independent dataset of additional 46 PD individuals was used further.Results: The PD-CI group showed a relatively lower end-diastolic blood flow velocity (EDV, p < 0.05) and a higher resistive index (RI, p < 0.05) compared to the PD-NC group. RI showed significant associations with the memory item score of Montreal Cognitive Assessment (p < 0.05). A model combining clinical and hemodynamic variables was established with optimal efficiency (area under the curve, AUC = 0.651). Further replication of the model in an independent dataset yielded a great consistency (AUC = 0.704).Conclusion: In our study, cerebrovascular functions were significantly associated with the cognitive performance in PD individuals, especially with the memory task. The established model was effective in identifying CI in PD individuals, which might be a potentially useful tool to screen the cognitive decline in PD individuals at an early stage of the disease. Further studies with larger sample sizes in different populations are warranted.Keywords: Parkinson’s disease, cognitive impairment, transcranial ultrasound, resistive index

The thermophysical properties of liquid metals and alloys are crucial to explore the intrinsic mechanisms of the solidification process, glass formation, and fluid dynamics. The deep learning approaches have emerged as powerful tools in numerous scientific fields and exhibit extraordinary accuracy in the estimation of physical properties and structural characteristics for various materials. In this Tutorial, focusing on the thermophysical properties of liquid multicomponent alloys, deep learning methods, including both supervised learning and active learning, are introduced. Combined with the verification from electrostatic and electromagnetic levitation experiments, the influences of training parameters and methods on the accuracy to obtain interatomic potential by deep learning are revealed on the basis of deep neural network algorithm. As a result, this prediction method of liquid state properties for multicomponent alloys exhibited the dual advantages of high accuracy derived from density functional theory and low computational cost associated with empirical potential. [ABSTRACT FROM AUTHOR]

Mengjia Zhi,1 Linlin Hu,1 Fangli Geng,2 Ningjun Shao,3 Yuanli Liu1 1School of Health Policy and Management, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100710, People’s Republic of China; 2Ph.D. Program in Health Policy, Harvard University Graduate School of Arts and Sciences, Cambridge, MA, USA; 3Jinhua Healthcare Security Administration, Zhejiang, 321000, People’s Republic of ChinaCorrespondence: Linlin Hu; Yuanli Liu, School of Health Policy and Management, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100710, People’s Republic of China, Tel/Fax +86 65105830, Email hulinlin@sph.pumc.edu.cn; Liuyuanli_pumc@163.comPurpose: Post-acute care is fast developing in China, yet a payment system for post-acute care has not been established. As stroke is the leading cause of mortality and disability in China, patients constitute a large share of post-acute-care patients among all hospitalized patients. This study was to identify the cost determinants and establish a case-mix classification of the post-acute care system for stroke patients in China.Patients and Methods: A total of 5401 post-acute stroke patients in seven hospitals of Jinhua City from January 2018 to December 2020 were selected. Demographic characteristics, medical status, functional measures (eg, the Barthel Index, Mini-Mental State Examination, Gugging Swallowing Screen, Hamilton Depression Scale), and cost data were extracted. Generalized linear model (GLM) and quantile regression (QR) were conducted to determine the predictors of cost, and a case-mix classification model was established using the decision-tree analysis.Results: The GLM regression revealed that gender, tracheostomy, complication or comorbidity (CC), activities of daily living (ADL), and cognitive impairment were the main variables significantly affecting the hospitalization expenses of post-acute stroke patients. The QR model showed that the gender, tracheostomy and CC factors had a more significant impact on per diem costs on the upper quantiles. In contrast, cognitive impairment had a more substantial effect on the lower quantiles, and ADL significantly impacted the central quantile. Using tracheostomy, CC, and ADL as node variables of the regression tree, 12 classes were generated. The case-mix classification performed reliably and robustly, as measured by the reduction in the variation statistic (RIV=0.46) and class-specific coefficients of variation (CV less than 1.0; range: 0.18– 0.81).Conclusion: QR has strengths in comprehensively identifying cost predictors across cost groups. Tracheostomy, CC, and ADL significantly can predict the expenses of post-acute care for stroke patients. The established case-mix classification system can inform the future payment policy of post-acute care in China.Keywords: cost, case-mix, post-acute care, stroke, quantile regression, decision-tree model

Xuguang Chen,&ast; Shengyi Shi,&ast; Lan Hu Department of Emergency, Ruijin Hospital, Shanghai Jiao Tong University School of Medical, Shanghai, 201800, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Lan Hu, Department of Emergency, Ruijin Hospital, Shanghai Jiao Tong University School of Medical, Shanghai, 201800, People’s Republic of China, Tel +86 181-2126-3197, Email 442037735@qq.comObjective: To investigate whether D-dimer levels and changes in D-dimer levels can be used as effective indexes to evaluate the risk of death among intraparenchymal haemorrhage (IPH) patients.Methods: A retrospective cohort study of 732 patients with IPH was conducted at an academic medical centre. The risk factors for adverse hospitalization outcomes were analysed, and logistic multivariate analysis was performed. Patients were divided into supratentorial, brainstem and cerebellum groups. According to whether intraventricular haematoma (IVH) and subarachnoid haematoma (SAH) co-occurred, the supratentorial group was divided into simple haematoma, combined IVH, combined SAH and combined IVH+SAH subgroups. The relationship between D-dimer levels and hospitalization outcome in each group/ subgroup was analysed.Results: Compared with survivors, the plasma D-dimer level of the nonsurvivors on the second day after admission was significantly higher (2.52 ± 3.89 μg/mL vs 0.77 ± 2.31 μg/mL, P = 0.032), and the difference in plasma D-dimer levels between the second day after admission and admission significantly increased (1.77 ± 3.70 μg/mL vs 0.26 ± 2.80 μg/mL, P = 0.049), and a D-dimer level on day 2 > 0.58 μg/mL was an independent risk factor for mortality among IPH patients (OR 3.114, 95% CI: 1.007). In the supratentorial group and the IVH subgroup, the level of D-dimer on day 2 was significantly higher among nonsurvivors than among survivors (2.18 ± 2.13 μg/mL vs 0.65 ± 1.04 μg/mL, P = 0.011; 2.45 ± 2.31 μg/mL vs 0.91 ± 1.26 μg/mL, P = 0.028, respectively).Conclusion: The increase in plasma D-dimer levels on day 2 is related to poor hospitalization outcomes of patients with IPH, and this correlation may exist only among patients with both IVH and IPH.Keywords: intraparenchymal hemorrhage, D-dimer, hospitalization outcomes

The Zr37Hf16Ni12.5Cu12.5Al11Co6Nb5 bulk metallic glass (BMG) with strong glass-forming ability (GFA) and remarkable mechanical properties was designed, and its thermophysical properties were characterized simultaneously. The glass transition temperature reached up to 726 K, while the fragility index of 43 was derived by measuring alloy viscosity. The undercooled liquid of this BMG with such a low fragility index displayed a strong liquid behavior, corresponding to its small crystallization driving force and high GFA. The thermal expansion coefficient increased from 9.76 × 10−6 K−1 of glassy state to 2.71 × 10−5 K−1 of undercooled liquid, and the close-packed structure was evidenced by the low specific energy for free volume formation of 239.4 kJ/mol. Owing to its low free volume and high glass transition temperature, this BMG exhibited remarkable tensile and compressive yield strengths up to 1660.3 and 2042.3 MPa, respectively. [ABSTRACT FROM AUTHOR]

Background Maple syrup urine disease (MSUD) is an autosomal recessive metabolic disorder originating from defects in the branched-chain α-ketoacid dehydrogenase (BCKDH) complex encoded by BCKDHA , BCKDHB and DBT. This condition presents a spectrum of symptoms and potentially fatal outcomes. Although numerous mutations in the BCKDH complex genes associated with MSUD have been identified, the relationship between specific genotypes remains to be fully elucidated. Aim Our objective was to predict the pathogenicity of these genetic mutations and establish potential links between genotypic alterations and the clinical phenotypes of MSUD. Design Retrospective population-based cohort. Methods We analyzed 20 MSUD patients from the Children's Hospital at Zhejiang University School of Medicine (Hangzhou, China), recorded from January 2010 to December 2023. Patients' blood samples were collected by heel-stick through neonatal screening, and amino acid profiles were measured by tandem mass spectrometry. In silico methods were employed to assess the pathogenicity, stability and biophysical properties. Various computation tools were utilized for assessment, namely PredictSNP, MAGPIE, iStable, Align GVGD, ConSurf and SNP effect. Results We detected 25 distinct mutations, including 12 novel mutations. The BCKDHB gene was the most commonly affected (53.3%) compared to the BCKDHA gene (20.0%) and DBT gene (26.7%). In silico webservers predicted all novel mutations were disease-causing. Conclusions This study highlights the genetic complexity of MSUD and underscores the importance of early detection and intervention. Integrating neonatal screening with advanced sequencing methodologies is pivotal in ensuring precise diagnosis and effective management of MSUD, thereby significantly improving the prognosis for individuals afflicted with this condition. [ABSTRACT FROM AUTHOR]

Yanan Xu,1,&ast; Ying Jing,2,&ast; Lingfei Hu,2 Qiaoxiang Cheng,1 Huixia Gao,3 Zhi Zhang,3 Huiying Yang,2 Yuee Zhao,2 Dongsheng Zhou,2 Zhe Yin,2 Erhei Dai1,3 1Department of Clinical Laboratory Medicine, Hebei Medical University, Shijiazhuang, Hebei, 050011, People’s Republic of China; 2State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, People’s Republic of China; 3Department of Laboratory Medicine, The Fifth Hospital of Shijiazhuang, Hebei Medical University, Shijiazhuang, Hebei, 050021, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Erhei Dai; Zhe Yin, Tel +86-311-85814612 ; +86-10-66948557, Email daieh2008@126.com; jerry9yin@163.comPurpose: To establish a typing scheme for IncFIB replicon and to dissect genomic features of IncFIB-4.1/4.2 single-replicon plasmids.Methods: A total of 146 representative fully sequenced IncFIB-replicon-containing plasmids were selected to construct a phylogenetic tree of repBIncFIB sequences. A collection of nine IncFIB-4.1/4.2 single-replicon plasmids from China were fully sequenced here and compared with the first sequenced IncFIB-4.1/4.2 single-replicon plasmids from GenBank to dissect their genomic diversity.Results: In this study, a repB sequence-based scheme was proposed for grouping IncFIB replicon into seven primary types and further into 70 subtypes. A collection of nine IncFIB-4.1/4.2 single-replicon plasmids were fully sequenced here and compared with the first sequenced IncFIB-4.1/4.2 single-replicon plasmids from GenBank. These 11 plasmids had small backbones and shared only three key backbone markers repB together with its iterons, parABC, and stbD. Each plasmid contained one large accessory region (LAR) inserted into the backbone, and these 11 LARs had significantly distinct profiles of mobile genetic elements (MGEs) and resistance/metabolism gene loci. Antibiotic resistance regions (ARRs; the antibiotic resistance gene-containing genetic elements) were found in seven of these 11 LARs. Besides resistance genes, ARRs carried unit or composite transposons, integrons, and putative resistance units. IncFIB-4.1/4.2 single-replicon plasmids were important vectors of drug resistance genes. This was the first report of three novel MGEs: In1776, Tn 6755, and Tn 6857.Conclusion: Data presented here provided a deeper insight into diversity and evolution of IncFIB replicon and IncFIB-4.1/4.2 single-replicon plasmids.Keywords: IncFIB, IncFIB-4 single-replicon plasmids, large accessory regions, antibiotic resistance regions, In1776, Tn 6755, Tn 6857