bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetik und Diagnostik des primären Lymphödems
Authors: Kemper Charlotte , Danyel Magdalena , Ott Claus-Eric , Hägerling René
Published: March 2021

Einleitung Das primäre Lymphödem ist eine genetisch bedingte, angeborene Erkrankung, die durch einen unzureichenden Abtransport von Lymphflüssigkeit aufgrund einer Fehlbildung oder Fehlfunktion des Lymphgefäßsystems entsteht. Dabei tragen periphere und systemische Manifestationen zum letztendlichen Phänotyp bei. Neben peripheren Manifestationen des primären Lymphödems, v. a. Schwellungen der unteren Extremität, können auch systemische Manifestationen, wie z. B. Aszites, intestinale und pleurale Lymphangiektasien, Chylothorax, Pleura- und Perikarderguss oder auch der Hydrops fetalis, auftreten. In Abhängigkeit vom ursächlichen Gen und der zugrunde liegenden genetischen Veränderung unterscheiden sich sowohl die klinischen Manifestationen als auch der Ausprägungsgrad des Lymphödems.

Klassifikation Die Krankheitsbilder, die mit einem primären Lymphödem einhergehen, lassen sich in 5 Kategorien aufteilen: (1) Erkrankungen, die mit einer segmentalen Wachstumsstörung assoziiert sind und auf einem somatischen Mosaik beruhen, (2) syndromale Erkrankungen, (3) Erkrankungen, bei denen das primäre Lymphödem eine systemische Beteiligung aufweist, (4) kongenitale Krankheitsbilder und (5) nach dem ersten Lebensjahr auftretende (Late Onset) Krankheitsbilder.

Genetische Diagnostik Basierend auf der Klinik des Patienten und der Zuordnung zu einer der 5 Kategorien kann eine zielgerichtete genetische Diagnostik erfolgen, zunächst beginnend mit einer konventionellen zytogenetischen Untersuchung (Chromosomenanalyse) sowie einer molekularzytogenetischen Methode (Array-CGH). Anschließend kann eine molekulargenetische Untersuchung im Rahmen von Einzelgenanalysen, Panel-Untersuchungen oder Exom- sowie Ganzgenomsequenzierung durchgeführt werden, durch die genetische Varianten oder Mutationen aufgedeckt werden können, die als kausal für die Symptomatik identifiziert werden können.

Fazit Betroffene eines primären Lymphödems profitieren von einer gezielten genetischen Diagnostik, da die verschiedenen Krankheitsbilder meistens nur durch die Detektion einer assoziierten genetischen Veränderung diagnostiziert werden können und somit eine Aussage über Vererbung und Wiederholungsrisiko möglich ist.
Tryptophan N
1-Alkylation: Quick and Simple Access to Diversely Substituted Tryptophans
Authors: Junk Lukas , Papadopoulos Emanuel , Kazmaier Uli
Published: March 2021

The diversification of amino acid sidechains is a major challenge in the synthesis and derivatization of peptides for pharmaceutical applications. We herein present a new protocol to alkylate the indole-nitrogen (N1) of N
α-protected tryptophans. This method provides quick and epimerization-free access to tryptophan derivatives, which can directly be incorporated into peptides. Depending on the functionalities introduced in the side chain, different options for the late-stage modification of peptides are possible.
Loop Ileostomy in Europe's Tiniest Male Newborn for Meconium-Related Ileus
Authors: Till Holger , Singer Georg , Castellani Christoph , Urlesberger Berndt
Published: March 2021

With the advances of neonatology, the survival rate for “live-born periviable fetuses” weighing < 300 g, a subgroup of extremely low birth weight (BW) infants, has improved over the past 10 years. Meconium-related ileus (MRI) represents an early postnatal hazard, and, if medical evacuation fails, a surgical challenge in such immature babies. We report the interdisciplinary management of surgically treated MRI in a newborn with a BW of 273 g. According to the worldwide database held by the University of Iowa, he is registered as the tiniest male newborn in Europe. The boy was born in the 25th gestational week by cesarean section after a triplet pregnancy with twin–twin transfusion syndrome, him being the donor. He had a BW of 273 g, whereas his brothers had a BW of 740 g and 722 g. Cardiopulmonary stabilization and ventilation were successful. He developed MRI unresponsive to medical treatment. On day 14 of life, a minilaparotomy was performed in the right lower quadrant to externalize a loop of the distal ileum in a no-touch technique. Despite the small diameter of only 2 mm, a standard loop ileostomy could be fashioned. There were no intra- or postoperative abdominal complications. Bowel function and weight gain were adequate and the ileostomy was closed electively 5 months later at a body weight of 3.5 kg.

In summary, minilaparotomy and loop ileostomy placement were effective to treat surgical MRI in Europe's tiniest male newborn. With the advances of neonatology, pediatric surgery reaches new frontiers as well.
In Vitro Assessment of Cytoprotective Effects of CANOVA against Cell Death Induced by the Anti-malarial Artesunate – A Preliminary Experiment
Authors: Bonfim Laís Teixeira , Bahia Marcelo de Oliveira
Published: March 2021

Background Artesunate (ATS) is a semi-synthetic compound derived from artemisinin, which is widely accepted in the treatment of malaria. However, there is evidence that ATS, under certain in vitro conditions, induces several impairments to normal cell functions. Canova (CA) is a Brazilian homeopathic formulation indicated for patients with depressed immune system. CA shows both in vitro and in vivo protective effects against mutagenic/carcinogenic compounds. Therefore, we aimed to assess in vitro the cytoprotective effects of CA against the cytotoxicity of ATS in Vero cells.

Methods Viability of Vero cells exposed to ATS was assessed by MTT assay, whereas the anti-cytotoxic effect of CA was evaluated by apoptosis and necrosis quantification with fluorescent dyes.

Results After 24 hours of ATS treatment, a reduction in cell viability was observed at 32 and 64 µg/mL, the latter being statistically significant (p < 0.05) in relation to the negative control. The concentration of 64 µg/mL was chosen for the subsequent experiments. ATS significantly induced both apoptosis and necrosis in Vero cells in relation to controls (p < 0.01). We also observed a statistically significant decrease in the number of apoptotic cells observed in the CA 16% + ATS co-treatment compared with ATS treatment (p < 0.01). Treatment with CA alone also had no influence on either type of cell death.

Conclusion Our results demonstrated that ATS is cytotoxic in the assessed conditions. However, such cytotoxicity was attenuated when the cells were treated simultaneously with ATS and CA.
The Development and Piloting of the Ambulatory Electronic Health Record Evaluation Tool: Lessons Learned
Authors: Co Zoe , Holmgren A. Jay , Classen David C. , Newmark Lisa P. , Seger Diane L. , Cole Jessica M. , Pon Barbara , Zimmer Karen P. , Bates David W.
Published: March 2021

Background Substantial research has been performed about the impact of computerized physician order entry on medication safety in the inpatient setting; however, relatively little has been done in ambulatory care, where most medications are prescribed.

Objective To outline the development and piloting process of the Ambulatory Electronic Health Record (EHR) Evaluation Tool and to report the quantitative and qualitative results from the pilot.

Methods The Ambulatory EHR Evaluation Tool closely mirrors the inpatient version of the tool, which is administered by The Leapfrog Group. The tool was piloted with seven clinics in the United States, each using a different EHR. The tool consists of a medication safety test and a medication reconciliation module. For the medication test, clinics entered test patients and associated test orders into their EHR and recorded any decision support they received. An overall percentage score of unsafe orders detected, and order category scores were provided to clinics. For the medication reconciliation module, clinics demonstrated how their EHR electronically detected discrepancies between two medication lists.

Results For the medication safety test, the clinics correctly alerted on 54.6% of unsafe medication orders. Clinics scored highest in the drug allergy (100%) and drug–drug interaction (89.3%) categories. Lower scoring categories included drug age (39.3%) and therapeutic duplication (39.3%). None of the clinics alerted for the drug laboratory or drug monitoring orders. In the medication reconciliation module, three (42.8%) clinics had an EHR-based medication reconciliation function; however, only one of those clinics could demonstrate it during the pilot.

Conclusion Clinics struggled in areas of advanced decision support such as drug age, drug laboratory, and drub monitoring. Most clinics did not have an EHR-based medication reconciliation function and this process was dependent on accessing patients' medication lists. Wider use of this tool could improve outpatient medication safety and can inform vendors about areas of improvement.
Delayed Diagnosis of a Pyloric Web Causing Gastric Outlet Obstruction in a 13-Month-Old Girl
Authors: Elifranji Mohammed , Sankar Jisha , Abdelrasool Israa , Brisseau Guy
Published: March 2021

Pyloric web is a rare cause of gastric outlet obstruction. Classical pyloric web can be diagnosed by obtaining a patient history, physical examination, and plain abdominal X-ray, whereas a perforated web leads to incomplete intestinal obstruction. Delayed diagnosis is rare, and the definite diagnosis is made by upper endoscopy. In this report, we report a case of a girl in whom a pyloric web was diagnosed at the age of 13 months.
Centralization of Biliary Atresia: Has Germany Learned Its Lessons?
Authors: Madadi-Sanjani Omid , Fortmann David , Rolle Udo , Rodeck Burkhard , Sturm Ekkehard , Pfister Eva-Doreen , Kuebler Joachim F. , Baumann Ulrich , Schmittenbecher Peter , Petersen Claus
Published: March 2021

Introduction The majority of pediatric surgeons and hepatologists recommend the centralization of biliary atresia (BA) treatment within experienced liver units. We aimed to investigate whether voluntary self-restriction and acceptance of the need for this change in practice changed the BA referral policy in Germany during the last decade.

Materials and Methods In cooperation with pediatric surgeons, gastroenterologists or hepatologists, and pediatric liver transplant units, the 2-year follow-up data of infants with BA born in Germany between 2010 and 2014 were collected using www.bard-online.com or pseudonymized data transfer. Results were compared with our previous analysis of the outcome data of infants with BA born between 2001 and 2005 in Germany.

Result Overall, 173 infants with BA were identified, of whom 160 underwent Kasai portoenterostomy (KPE; 92.5%) and 13 (7.5%) underwent primary liver transplantation at 21 German centers. At 2-year follow-up, overall survival was 87.7% (vs. 81.9% in 2001–2005 [p = 0.19]), survival with native liver post-KPE was 29.2% (vs. 22.8% in 2001–2005 [p = 0.24]), and jaundice-free survival with native liver post-KPE was 24.0% (vs. 20.1% in 2001–2005 [p = 0.5]). Compared with the 2001–2005 analysis, all criteria showed improvement but the differences are statistically not significant.

Conclusion Our observation shows that KPE management requires improvement in Germany. Centralization of BA patients to German reference liver units is not yet mandatory. However, European and national efforts with regard to the centralization of rare diseases support our common endeavor in this direction.
Clinical Neurorehabilitation: Using Principles of Neurological Diagnosis, Prognosis, and Neuroplasticity in Assessment and Treatment Planning
Authors: Katz Douglas I. , Dwyer Brigid
Published: March 2021

Neurorehabilitation aspires to restore a person to his or her fullest potential after incurring neurological dysfunction. In medical rehabilitation, diagnosis involves assessment of medical conditions and their effects on functioning. It is usually a team effort that involves an amalgam of diagnostic assessments by multiple disciplines, leading to a collection of rehabilitative treatment plans and goals. This article discusses a clinical neurological paradigm, using rigorous clinical assessment of neuropathological and clinical diagnosis, along with prognostication of natural history and recovery. In the context of the role of neuroplasticity in recovery, this paradigm can add significant value to rehabilitation team management and planning. It contributes to enhanced understanding of neurological impairments and syndromes as they relate to functional disability, aiding in targeting deficits and setting treatment goals. Rehabilitation strategies and goals should be informed by natural history and prognosis, and viewed in the framework of the stage of recovery. Prognostic formulations should suggest an emphasis on restorative versus compensatory strategies for functional problems. Treatment planning should be informed by evidence on how interventions modulate brain reorganization in promoting recovery. Strategies that promote adaptive neuroplasticity should be favored, especially with restorative efforts, and evidence supporting optimal techniques, timing, and dosing of rehabilitation should be considered in treatment planning.
Bowel Lengthening Procedures in Children with Short Bowel Syndrome: A Systematic Review
Authors: Nagelkerke Sjoerd C. J. , Poelgeest M. Y. van , Wessel L. M. , Mutanen A. , Langeveld H. R. , Hill S. , Benninga M. A. , Tabbers M. M. , Bakx R. ,   on behalf of the ERNICA Intestinal Failure Working Group
Published: March 2021

Introduction The aims of the study are to systematically assess and critically appraise the evidence concerning two surgical techniques to lengthen the bowel in children with short bowel syndrome (SBS), namely, the longitudinal intestinal lengthening and tailoring (LILT) and serial transverse enteroplasty (STEP), and to identify patient characteristics associated with a favorable outcome.

Materials and Methods MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched from inception till December 2019. No language restriction was used.

Results In all, 2,390 articles were found, of which 40 were included, discussing 782 patients. The median age of the patients at the primary bowel lengthening procedure was 16 months (range: 1–84 months). Meta-analysis could not be performed due to the incomparability of the groups, due to heterogeneous definitions and outcome reporting. After STEP, 46% of patients weaned off parenteral nutrition (PN) versus 52% after LILT. Mortality was 7% for STEP and 26% for LILT. Patient characteristics predictive for success (weaning or survival) were discussed in nine studies showing differing results. Quality of reporting was considered poor to fair.

Conclusion LILT and STEP are both valuable treatment strategies used in the management of pediatric SBS. However, currently it is not possible to advise surgeons on accurate patient selection and to predict the result of either intervention. Homogenous, prospective, outcome reporting is necessary, for which an international network is needed.
Dens Invaginatus: A Report of Two Cases
Authors: Agnihotri Archna , Arora Rosy , Bida Lalit , Sharma Urvashi
Published: March 2021

Dens invaginatus (DI) is an anomaly of developmental origin arising due to disturbances during the morphodifferentiation stage, resulting from infolding of enamel organ toward the dental papilla. Different presentations of the invagination, altered canal morphology, and presence of constrictions and dilatations sometimes make its management really challenging. With the advent of modern diagnostic and treatment aids, their easy availability and routine use, it is now possible to have detailed view of the invagination, thus making the management easy and the outcome predictable. This article presents two different presentations of DI and their management.
A stellar/inertial integrated navigation method based on the observation of the star centroid prediction error
Authors: Ni Yuanman , Tan Wenfeng , Dai Dongkai , Wang Xingshu , Qin Shiqiao
Published: March 2021

The stellar/inertial integrated navigation system, which combines the inertial navigation system (INS) and the star tracker, can restrain the accumulated INS errors. In the traditional loosely coupled stellar/inertial integration method, the star tracker needs to observe more than two navigation stars on an image for attitude determination and to use the attitude information as the observation to estimate the systematic errors of the INS. However, under strong background radiation conditions, the star number in the field of view (FOV) usually drops below 3; thus, the loosely coupled method fails to work. To overcome this difficulty, an improved tightly coupled stellar/inertial integration method based on the observation of the star centroid prediction error (SCPE) is proposed in this paper. It calculates the difference between the extracted star centroid and the predicted star centroid, namely, the SCPE, as the observation and then estimates the INS errors with a Kalman filter. Numerical simulations and ground experiments are conducted to validate the feasibility of the tightly coupled method. It is proved that the proposed method, which makes full use of all star observation information, can improve the navigation accuracy compared with the loosely coupled method and is more robust when there are not enough stars in the FOV.
Euler–Lagrange study of bubble breakup and coalescence in a turbulent boundary layer for bubble drag reduction
Authors: Zhang Xiaosong , Wang Jianhua , Wan Decheng
Published: March 2021

By injecting bubbles on the surface of ships or underwater vehicles, friction resistance can be effectively reduced. This technique is known as bubble drag reduction (BDR). The Euler–Lagrange method has been proved to be an effective numerical method in the study of the BDR mechanism. Bubble diameters were uniform in previous Euler–Lagrange simulations. However, many experimental results indicated that there is a nonuniform bubble size distribution under the action of turbulence, which affects the drag reduction significantly. In this paper, the authors developed a Euler–Lagrange code with the ability to simulate bubble breakup and bubble coalescence. The process of BDR on a flat plate is simulated by injecting bubbles into a turbulent boundary layer flow. Diameters of the bubbles are the same when they are injected into the flow field. During the simulation, bubbles of varying sizes can be clearly simulated in the evolution process due to breakup and coalescence. The drag reduction effect and bubble size distribution are validated by comparison with previous experimental data. Numerical results with and without breakup and coalescence models are discussed in detail to illustrate the advantage of the present algorithm. Moreover, bubble size distribution, bubble trajectory, and bubble induced turbulent modulation are analyzed in detail to explain the mechanism and its relationship with bubble size distribution.
Wing-tip vortex dynamics at moderate Reynolds numbers
Authors: Smith T. A. , Ventikos Y.
Published: March 2021

The flow over a flat-tipped wing at three Reynolds numbers: Re=1×104, Re=4×104, and Re=1×105 is investigated using direct numerical simulation. A set of grid independent results are obtained which allow for the dynamics of the tip flow, trailing vortices, and their interplay with the boundary layer dynamics to be examined in detail. The results show significant changes across the Reynolds number range. At the lowest Reynolds number, a single trailing vortex forms downstream of the trailing edge, whereas multiple vortices form over the tip at higher Reynolds numbers. The tip geometry is shown to be important with regard to the development of different structures and in the transition of the flow from laminar to turbulent. This is due to unstable shear layers, with turbulent flow becoming entrained in the vortex cores at higher Reynolds numbers. These changing vortex dynamics mean that the value of the minimum vortex core pressure and its location change with Reynolds number. This has important consequences for cavitation inception and scaling for hydrodynamic applications. The influence of the tip flow on the boundary layer is further considered by comparing the flow with that of an infinite-span wing. Analysis of the two cases shows that the tip flow reduces the effective angle of attack, which prevents the flow separation at the leading edge that is responsible for the boundary layer transition for the infinite-span case. This, in turn, changes the character of the trailing edge flow which would have significant consequences on the trailing edge noise.
Lagrangian pair dispersion in upper-ocean turbulence in the presence of mixed-layer instabilities
Authors: Berti Stefano , Lapeyre Guillaume
Published: March 2021

Turbulence in the upper ocean in the submesoscale range (scales smaller than the deformation radius) plays an important role for the heat exchanges with the atmosphere and for oceanic biogeochemistry. Its dynamics should strongly depend on the seasonal cycle and the associated mixed-layer instabilities. The latter are particularly relevant in winter and are responsible for the formation of energetic small scales that extend over the whole depth of the mixed layer. The knowledge of the transport properties of oceanic flows at depth, which is essential to understand the coupling between surface and interior dynamics, however, is still limited. By means of numerical simulations, we explore the Lagrangian dispersion properties of turbulent flows in a quasi-geostrophic model system allowing for both thermocline and mixed-layer instabilities. The results indicate that, when mixed-layer instabilities are present, the dispersion regime is local from the surface down to depths comparable with that of the interface with the thermocline, while in their absence dispersion quickly becomes nonlocal with depth. We then identify the origin of such behavior in the existence of fine-scale energetic structures due to mixed-layer instabilities. We further discuss the effect of vertical shear on the Lagrangian particle spreading and address the correlation between the dispersion properties at the surface and at depth, which is relevant to assess the possibility of inferring the dynamical features of deeper flows from the more accessible surface ones.
Position-dependent chiral coupling between single quantum dots and cross waveguides
Authors: Xiao Shan , Wu Shiyao , Xie Xin , Yang Jingnan , Wei Wenqi , Shi Shushu , Song Feilong , Sun Sibai , Dang Jianchen , Yang Longlong , Wang Yunuan , Zuo Zhanchun , Wang Ting , Zhang Jianjun , Xu Xiulai
Published: March 2021

Chiral light–matter interaction between photonic nanostructures with quantum emitters shows great potential to implement spin–photon interfaces for quantum information processing. Position-dependent spin momentum locking of the quantum emitter is important for these chiral coupled nanostructures. Here, we report the position-dependent chiral coupling between quantum dots (QDs) and cross waveguides both numerically and experimentally. Four quantum dots distributed at different positions in the cross section are selected to characterize the chiral properties of the device. Directional emission is achieved in a single waveguide and in both two waveguides simultaneously. In addition, the QD position can be determined with the chiral contrasts from four outputs. Therefore, the cross waveguide can function as a one-way unidirectional waveguide and a circularly polarized beam splitter by placing the QD at a rational position, which has potential applications in spin-to-path encoding for complex quantum optical networks at the single-photon level.
Cas9-expressing chickens and pigs as resources for genome editing in livestock
Authors: Rieblinger Beate , Sid Hicham , Duda Denise , Bozoglu Tarik , Klinger Romina , Schlickenrieder Antonina , Lengyel Kamila , Flisikowski Krzysztof , Flisikowska Tatiana , Simm Nina , Grodziecki Alessandro , Perleberg Carolin , Bähr Andrea , Carrier Lucie , Kurome Mayuko , Zakhartchenko Valeri , Kessler Barbara , Wolf Eckhard , Kettler Lutz , Luksch Harald , Hagag Ibrahim T. , Wise Daniel , Kaufman Jim , Kaufer Benedikt B. , Kupatt Christian , Schnieke Angelika , Schusser Benjamin
Published: March 2021

Significance

Genetically modified animals are crucial for functional studies and translational biomedical research. However, the generation of genome-edited large animals is time consuming and inefficient. Here, we report the generation of transgenic pigs and chickens that ubiquitously express Cas9 nuclease. The functionality of Cas9 was demonstrated for different target genes, a variety of cell types, and in vivo for the heart and the developing brain. Genome editing can now easily be carried out in vivo in specific organs or tissues without the need to generate germline-modified animals. These Cas9 transgenic animals provide an innovative and efficient resource for in vivo genome editing in biomedical and agricultural sciences.
Effect of spherical inclusions on fatigue anisotropy of HSLA-100 steel
Authors: Abyazi Arezou , Ebrahimi Ali Reza
Published: March 2021

The fatigue limit of the transverse direction was obtained remarkably (125 MPa) lower than that of the longitudinal direction. The fatigue anisotropy was related to different characteristics of inclusions on longitudinal and transverse planes as well as the crystallographic texture. These parameters change the fatigue crack initiation mode from the metal matrix to spherical inclusions. Exaggeratedly conservative results were obtained utilising the Murakami's model in predicting the lower bound fatigue limit and largest size of inclusion.
Microstructural, mechanical and wear behaviour of Inconel-718 produced through laser-powder bed-fused additive manufacturing
Authors: Jeyaprakash N. , Yang Che-Hua , Ramkumar K. R.
Published: March 2021

The present work deals with the microstructure, nanoindentation and wear behaviour of Inconel-718 (IN-718) specimens fabricated through laser-powder bed fusion (L-PBF). To ensure the improvement in L-PBF, the results obtained were compared with the as-cast IN-718 specimen. Though IN-718 specimens exhibited precipitation and solid solution strengthening in both the fabrication techniques, L-PBF specimen has achieved better mechanical properties due to refinement of grains. The wear rate of cast and L-PBF IN-718 specimens were 0.98 and 0.27 mm3 m−1, respectively. Besides, the roughness average was reduced for L-PBF produced worn surface compared to as-cast specimen. In the light of the above observations, L-PBF can be a promising technique to fabricate IN-718 alloys for load carrying and wear applications.
Stabilisation wedges: measuring progress towards transforming the global energy and land use systems
Authors: Johnson Nathan , Gross Robert , Staffell Iain
Published: March 2021

Fifteen years ago, Pacala and Socolow argued that global carbon emissions could be stabilised by mid-century using a portfolio of existing mitigation strategies. We assess historic progress for each of their proposed mitigation strategies and convert this into the unit of ‘wedges’. We show that the world is on track to achieve 1.5 ± 0.9 wedges relative to seven required to stabilise emissions, or 14 required to achieve net-zero emissions by mid-century. Substantial progress has been made in some domains that are not widely recognised (improving vehicle efficiency and declining vehicle use); yet this is tempered by negligible or even negative progress in many others (particularly tropical tree cover loss in Asia and Africa). By representing global decarbonisation efforts using the conceptually simple unit of wedges, this study helps a broader audience to understand progress to date and engage with the need for much greater effort over the coming decades.
Landscape Patterns of Wetland Parks in Suzhou based on ArcGIS and Fragstats: a Case Study of Huqiu Wetland Park and Taihu Hubin National Wetland Park
Authors: Bi Yu , Ma Jianwu , Li Shuangqi
Published: March 2021

Taking Huqiu Wetland Park and Taihu Hubin National Wetland Park as the study objects, ArcGIS and Fragstats techniques were used to analyze the landscape pattern characteristics of the two parks in terms of patch type and landscape level. The results showed that the landscape types of both Huqiu Wetland Park and Taihu Hubin National Wetland Park were dominated by wetlands, accounting 37.7% and 82.24% of the total park area of the pars respectively. The aggregation index were 99.72 and 99.96 respectively, and the aggregation of wetland patches in Taihu Hubin National Wetland Park was higher. The percentages of grassland and built-up area were higher in Huqiu Wetland Park than in Taihu Hubin National Wetland Park, but plaque agglomeration was lower than that in Taihu Hubin National Wetland Park. In terms of landscape diversity, Huqiu Wetland Park's Shannon Diversity Index of 1.33 and Shannon Uniformity Index of 0.83 were both higher than Taihu Hubin National Wetland Park's 0.63 and 0.45, indicating that dominant landscape was not sufficiently prominent and that the patch. The differences in landscape patterns between the two wetland parks are related to their planning design, regional location, surrounding environment and human disturbance.
Comprehensive Application of Multi-beam Sounding System and Side-scan Sonar in Scouring Detection of Underwater Structures in Offshore Wind Farms
Authors: Chen Chao , Tian Yu
Published: March 2021

In recent years, the installed capacity and power generation of offshore wind power have continued to grow rapidly, operation and maintenance testing has faced many technical challenges. Among them, the monitoring of the scour status of the underwater structure of the wind turbine and the complete basic data of the wind turbine's full life cycle management system are of great significance to ensuring the long-term safe and stable operation of the offshore wind farm. This paper introduces the application of a combined multi-beam bathymetric system and side-scan sonar in the scour detection of underwater structures of wind farms based on an example of offshore wind farm detection in the East China Sea. The combination of the two can effectively achieve complementary advantages and obtain more detailed and accurate water depth data and underwater structure images. It provides reliable basic data support for the operation and maintenance of offshore wind farms and the establishment of life cycle management system.
Research on the Situation of In-use Consistency of China V Heavy Diesel Vehicles in Shenzhen
Authors: Zhang Nina , Miao Ling
Published: March 2021

In order to explore the current status of in-use compliance of China V heavy-duty diesel vehicles in Shenzhen, five China V heavy-duty diesel vehicles were tested for NOX emissions using the LugDown cycle, and CO, NOX, and PM emissions were tested for these vehicles using the Portable Emissions Measurement System (PEMS).The test results showed that all 5 vehicles meet the NOX limit requirements of the LugDown test method, and 2 vehicles exceeded the limit requirements of the PEMS test method. For 3 vehicles below the PEMS test NOX limit, the difference in the average value of the two test methods was 14%-18%, and the median difference was 1%-63%; For the two vehicles that exceeded the PEMS test NOX limit, the average difference was 32%-63%, and the median difference was 81%-127%. For vehicles with higher NOX emissions, the LugDown test was not able to reflect the actual situation of real driving emission well. The particulate emission test results showed that the difference in the removal efficiency of different diesel particulate filter could reach more than 113 times, and the difference in the technology of cleaning in engine could reach more than 6 times. The study showed that the current status of compliance of in-use China V standard heavy-duty diesel vehicles was not optimistic.
Microplastic Distribution in Soils from the Typical Sparsely Populated Area, Northwest China
Authors: Sun Yichen , Cao Lu , Zhou Bin , Wu Di , Li Qiang
Published: March 2021

In order to improve the knowledge of the microplastic pollution in the sparsely populated area, a preliminary monitoring survey was carried out in the northwest of China. Microplastics were evaluated in 28 soils collected from 6 sites by the methods of density separation and identified by microscope and Flourier infrared spectrum instrument. Microplastics were detected in all sampling points but the abundances, morphologies and polymers varied in different sampling points due to the natural conditions and anthropogenic influences. And the size of the detected microplastics is larger in comparison with other study areas. But with time, the degraded microplastics still could threat the ecology and environment. This study is helpful to get the whole pictures of microplastics around the world.
Design of the Highly Integrated Indoor Environment Monitoring System with Dual Data Transmission Mode Based on the Interconnect of Things
Authors: Chen Hang , Zhang Zhongwei , Li Jieming , Liu Shubo , Liu Xi , Qiao Shengfang
Published: March 2021

To overcome the disadvantages of poor adaptability and weak systematicity of the existing indoor environment monitoring instrument, a set of indoor environment monitoring system with dual data transmission mode based on the Interconnect of Things is designed in this paper, which can monitor seven different related parameters, i.e., fusion CO2, formaldehyde, volatile organic compounds, particulate matter, temperature, humidity and noise. Besides, it designs dual mode switch between GSM wireless upload and WiFi wireless upload to enhance the environmental adaptability of the monitor. It was demonstrated that, by combining with the he Internet of Things technology, the system works well to incorporate monitoring, assessment and early warning.
Recent Shoreline Variations Analysis Using Landsat 8 OLI Imagery in East Dongting Lake, China
Authors: Zhou Junjie , Ou Mingwu , Shi Jia , Li Ying
Published: March 2021

Dongting Lake, located in the northeast of Hunan Province, is the second largest fresh water lake in China. Based on Landsat 8 OLI imagery in 2013 and 2016, the shoreline of East Dongting Lake in different periods was explained through processing of radiation correction, geometric correction and band combination, etc., and the temporal sequence variation characteristics of the lake shoreline were explored. The results show that there is no obvious variation in the shoreline around the lake, and the area of East Dongting Lake is stable of 1300km2. Typical shoreline monitoring in the lake area shows that recently there is a new enclosed area in the middle of the Luhu Reed Field. The enclosed area covers an area of 1.98km2, about 3,000 mu, and the top elevation of the enclosed area is between 30 and 32m. Moreover, East Dongting Lake is an internationally important wetland reserve and a significant regulating lake of the Yangtze River. The shoreline of East Dongting Lake is stable latterly, but the development of low enclosure and net enclosure in the lake area has not been prohibited for a long time. As far as the lake area management is concerned, we should pay more attention to supervision of illegal activities such as enclosing land in the lake area.
Remote Sensing Retrieval and Evaluation of Chlorophyll-a Concentration in East Dongting Lake, China
Authors: Chen Xi , Ou Mingwu , Jia Shi , Li Ying
Published: March 2021

Using Landsat 8 OLI remote sensing images in November 2016, October 2017 and December 2017, relevant quantitative remote sensing statistical models were adopted under the ENVI software platform to invert and evaluate the chlorophyll-a (Chl-a) concentration in East Dongting Lake, China. The results show that from 2016 to 2017, the maximum concentration of Chl-a was 28 mg/m3, with an average of 16 mg/m3. The water temperature is relatively high in summer, and the photosynthesis of algae is enhanced, which is conducive to the growth and reproduction of algae. The concentration is relatively high in flood season, and the non-flood season is relatively low. In the northwest of East Dongting Lake, there is no free exchange of water with the shore, and the water in the lake has a relatively low purification capacity for pollutants; Chl-a concentration in this region is higher than that in other regions, while the water in the channel connecting South Dongting Lake has strong fluidity with low concentration. In the flood season of July 2017, the trophic state index (TSI) value of the west inshore side of the lake can reach 60-70, and there is a problem of water bloom. The TSI of non-flood season is 40-50. The degree of eutrophication has decreased recently, which should be related to the overall management of water environment.
Evaluate the Effect of the Grain for Green Project on Vegetation Variation in Xiliugou Basin
Authors: Dong Guotao , Gu Jiahe , Lv Xizhi , Xue Huazhu , Lian Yaokang
Published: March 2021

Xiliugou Basin is one of the ten brooks that flow directly into the Yellow River, facing two key environmental problems: soil and water erosion and flood sediment disasters caused by storm runoff. In order to analyze the dynamic vegetation variation in Xiliugou Basin before and after Grain for Green Project (GGP), we used Normalized Difference Vegetation Index (NDVI) data to extract the series characteristics of vegetation changes from 1998 to 2010. The spatio-temporal effects of the GGP on land cover and vegetation coverage (VC) was characterized using TM/ETM+ images of 1998, 2002, 2007 and 2010. The results show that from 1998 to 2010, total VC was increasing, and areas with poor vegetation conditions declined significantly. Higher VC was for the most part spatially distributed around the river, while lower VC was present in the desert, which would be expected to have low coverage. A high spatial distribution was found in the upper reaches, while in the lower reaches it was low. Comparing the four periods, the VC distribution had substantial variation, particularly in the upper reaches. This was driven by the higher VC in grassland, which demonstrates that GGP can effectively rehabilitate ecosystems.
Experimental Study on Shear strength of Rock-Concrete Interface at Different Ages
Authors: Gao Chao , Zhu Zhaoqing , Ding Shijun , Ji Siyu
Published: March 2021

Aiming at the power grid engineering construction, the shear strength or friction resistance of rock-socketed digging pile foundations and rock bolt foundations are different. The basic dimensions designed by each unit are quite different, in the shear strength test device of rock concrete interface, tests on the shear strength of the rock-concrete interface of different rock types (limestone, marble, and granite) and ages (3-day and 21-day) have been carried out. The results show that, the bond strength of the rock-concrete interface of different ages is quite different. Within 21 days of age. The bond strength of the rock-concrete interface has a linear relationship with age.
Study on Nondestructive Test Method for Inner Defects of Mass Concrete
Authors: Cao Shuxue , Li Jun , Wang Jie , Yan Yongdong , Yang Jun , Zhao Hongbin
Published: March 2021

Due to the large geometric size and the influence of dense embedded steel bars, It is difficult to use the traditional nondestructive testing (NDT) method for evaluation the inner defects of mass concrete. A comprehensive nondestructive testing method for internal defects of mass concrete was proposed, which used elastic wave Computed Tomography (CT) scanning for general survey, ultrasonic tomography and ground penetrating radar (GPR) technology for fine investigation. The method was applied to the defect detection of a bearing platform concrete belonging to an interchange bridge. Finally, the reliability of this method was verified by the results of core drilling. The results show that the proposed method can effectively detect the distribution of defects in concrete, provided a new solution and practical guidance for the internal defect detection and reinforcement of mass concrete structure.
Analysis on Out-of-Plane Stability of Large-span Single Space Tube Truss during Hoisting
Authors: Chen S H , Yin T Y , Sang X X , Ye B R , Ding M
Published: March 2021

In order to study the out-of-plane stability of the large-span single space tube truss during lifting, the eigenvalue buckling mode of the truss was calculated by mode analysis in ANSYS, the eigenvalue buckling mode with different combination coefficients was applied to the truss, and the stability bearing capacity was taken as the measurement to conduct the whole process tracking analysis. Finally, the most appropriate eigenvalue buckling mode combination was found as the initial imperfection, and it was applied to a large-span single regular triangle space tube truss and inverted triangle space tube truss to verify its stability during hoisting, respectively. The results show that the combination form of the eigenvalue buckling mode is the most appropriate initial imperfection. When the large-span single regular triangle space tube truss and inverted triangle space tube truss are hoisted, local buckling occurs when the body force is up to 0.30 times and 0.15 times of gravity, respectively, and overall instability occurs when the body force is up to 0.56 times and 0.51 times of gravity, respectively. It can be obviously obtained that the large-span single space tube truss may be destabilized under its own weight during hoisting, local buckling has occurred in some member bars before overall instability, and it is necessary to check the truss stability before hoisting in actual engineering.
Experimental Study on Time-Dependent Deformation of Red-Bed Mudstone
Authors: Zhou Qijian , Deng Ronggui , Wang Xin , Wang Kai
Published: March 2021

The time-dependent deformation characteristics of mudstone are the keys to reveal the long-term deformation law, damage, failure mechanism of mudstone, and effective treatment of mudstone diseases. In this study, the influence of confining pressure on the deformation of Mudstone was studied through triaxial tests. Also, the effect of load classification on the aging deformation of red bed mudstone was studied by the creep test. The results indicated that: (1) the time effect on mudstone deformation was obvious; 1h to 10h was the acceleration deformation stage, 10h to 20h was the deceleration deformation stage, and 20h was the stable deformation stage; (2) the deformation characteristics of red bed mudstone were affected by confining pressure, and its peak strength and elastic modulus increased with the increase of confining pressure. There were upper limit value and lower limit value in amplitude variation; (3) in general, mudstone failure occurred when the total strain reached 0.01 to 0.015. The failure mode of mudstone was a shear failure when the graded load was large, and discrete failure when it was small. The main reason was that the rock mass was full of expansion and contraction when the graded load was small. Hence, micro-fractures were more likely to develop.
Research and Application of Underground Automatic Drilling Rig
Authors: Chen Xiang , Wang Song , Yang Jiangbo , Chen Fenglei
Published: March 2021

Aiming at the current situation of low automation of underground drilling equipment, an automatic drilling rig which is suitable for underground coal mines has been developed. This paper introduces the layout, parameters, characteristic advantages and the application of the drilling rig. Through the industrial test, the design rationality of the structure of the drilling rig, the reliability of key components for automatic drilling, the reliability of electro-hydraulic control system, and the practicality of automatic drilling function were verified, which reached the expected research and development goals and design requirements, met the technological requirements of automatic drilling in coal mines, enhanced the safety of construction personnel, and reduced the labor intensity.
Health Perception System Design Based on Sensor Internet of Things for Transmission Tower’s Structure Status
Authors: Ling Qi , Hu Bo , Shen Xiang , Liao Hailin , Ni Hongyu
Published: March 2021

By using Internet of Things smart terminal equipment based on low-power wireless sensing technology, integrated hybrid measurement technology and edge computing technology, this article designs a sensory perceptual system for structural health monitoring of transmission tower. This system have advantages over online monitoring, data fusion and unified transmission of status information related to tower inclination, structural stress, on-site images, status of lines and environmental meteorology, providing a practical and advanced solution for the informatization and intelligence of safe operation of the transmission tower, which can substantially improve the effectiveness and timeliness of patrol and protection, key positioning and early warning of hidden dangers of the transmission tower.
Nonlinear Dynamic Behaviors of the Arc Tooth Connected Rotor under Different Loads
Authors: Wang Longkai , Huang Qike , Wang Ailun , Yin Yijun , Heng Xing
Published: March 2021

Due to the wear of wheels during operation, the unbalance is induced. To study the nonlinear vibration of the arc tooth connected rotor under different loads, the motion equation was built based on Lagrange equation, considering contact property of the arc tooth and the oil-film force. From the GW rough surface model, the interface contact stiffness for the arc end-tooth was calculated. The eventual contact force was simulated by a nonlinear spring. Rich nonlinear dynamic phenomena, such as periodic doubling bifurcation phenomenon, multiperiodic motion, quasi periodic motion, oil whirl, etc., were observed. The results show distinct phenomena caused by the load variations. To reduce the nonsynchronous vibration, the relative phase is suggested to be kept at 120°.
Modeling of Stress Distribution During Portland Cement Curing in Temperature Gradient Conditions
Authors: Gnyrya Aleksei , Abzaev Yurii , Korobkov Sergei
Published: March 2021

The paper presents the two-dimensional model of Portland cement curing based on the finite element method. The cement curing lasts for 2 days in the temperature gradient conditions ranging from 65 to −20 °C. A cement rod 7×70 cm in size was used for modeling the von Mises stress distribution. It is shown that in the temperature gradient conditions, the stress maximum in curing Portland cement shifts toward the hot edge of the cement rod and exceeds the minimum stress level more than two times. The stress growth at the interfaces between the concrete timber and the cement rod exceeds the stress maximum inside the latter. This stress distribution is connected with the heat flow generation and superposition of direct and reverse heat flows. Superposition of the negative heat flows generates the stresses at the interfaces, which are higher than those generated by the positive heat flows. The concrete timber and the interface fixation are the additional factors that increase the stress level at the interfaces and promote the cement fracture.