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The Origin of the Flat Rotation Curves in Spiral Galaxies: The Hidden Roles of Glitching SMDEOs and Emission of Gravitational Waves

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Journal of Modern Physics 2024年第10期15卷 1523-1542页

作者： Ahmad A. Hujeirat Peter Berczik Interdisciplinary Center for Scientific Computing Faculty of Physics and Astronomy University of Heidelberg Heidelberg Germany Main Astronomical observatory Kyiv Ukraine

Supermassive DEOs (SMDEOs) are cosmologically evolved objects made of irreducible incompressible supranuclear dense superfluids: The state we consider to govern the matter inside the cores of massive neutron stars. These cores are practically trapped in false vacua, rendering their detection by outside observers impossible. Based on massive parallel computations and theoretical investigations, we show that SMDEOs at the centres of spiral galaxies that are surrounded by massive rotating torii of normal matter may serve as powerful sources for gravitational waves carrying away roughly 1042 erg/s. Due to the extensive cooling by GWs, the SMDEO-Torus systems undergo glitching, through which both rotational and gravitational energies are abruptly ejected into the ambient media, during which the topologies of the embedding spacetimes change from curved into flatter ones, thereby triggering a burst gravitational energy of order 1059 erg. Also, the effects of glitches found to alter the force balance of objects in the Lagrangian-L1 region between the central SMDEO-Torus system and the bulge, enforcing the enclosed objects to develop violent motions, that may explain the origin of the rotational curve irregularities observed in the innermost part of spiral galaxies. Our study shows that the generated GWs at the centres of galaxies, which traverse billions of objects during their outward propagations throughout the entire galaxy, lose energy due to repeatedly squeezing and stretching the objects. Here, we find that these interactions may serve as damping processes that give rise to the formation of collective forces f∝m(r)/r, that point outward, endowing the objects with the observed flat rotation curves. Our approach predicts a correlation between the baryonic mass and the rotation velocities in galaxies, which is in line with the Tully-Fisher relation. The here-presented self-consistent approach explains nicely the observed rotation curves without invoking dark matter or mo

关键词： General Relativity: Black Holes Neutron Stars Quantum Fields: QCD Condensed Matter Incompressibility Superfluidity Cosmology: Galaxy Formation Spiral Galaxies Dark Matter Rotation Curves

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Reversed-Phase-HPLC Assay Method for Simultaneous Estimation of Sorbitol, Sodium Lactate, and Sodium Chlorides in Pharmaceutical Formulations and Drug Solution for Infusion

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American Journal of Analytical Chemistry 2024年第2期15卷 57-71页

作者： Sreenivas Pippalla Venugopal Komreddy Srinivasulu Kasa Vaishnavi Chintala Poluri Venkata Reddy Department of Chemistry Sikkim Professional University Gangtok India Analytical Research & Development Hikma Pharmaceuticals USA Inc. Bedford USA Department of Chemistry Osmania University Hyderabad India Analytical Research & Development Cambrex High Point High Point USA Department of Analytical Chemistry Annamalai University Annamalai Nagar India

A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chlorides in a drug solution for infusion. Sorbitol, Sodium lactate, and Chloride are all officially recognized in the USP monograph. Assay methods are provided through various techniques, with titrations being ineffective for trace-level quantification. Alternatively, IC, AAS, and ICP-MS, though highly accurate, are costly and often unavailable to most testing facilities. When considering methods, it’s important to prioritize both quality control requirements and user-friendly techniques. A simple HPLC simultaneous method was developed for the quantification of Chlorides, Sorbitol, and Sodium Lactate with a shorter run time. The separation utilized a Shimpack SCR-102(H) ion exclusion analytical column (7.9 mm × 300 mm, 7 μm), with a flow rate of 0.6 mL per min. The column compartment temperature was maintained at 40°C, and the injection volume was set at 10 μL, with detection at 200 nm. All measurements were conducted in a 0.1% solution of phosphoric acid. The analytical curves demonstrated linearity (r > 0.9999) in the concentration range of 0.79 to 3.8 mg per mL for Sodium Lactate (SL), 0.16 to 0.79 mg per mL for Sodium Chloride (SC), and 1.5 to 7.2 mg per mL for Sorbitol. Validation of the developed method followed the guidelines of the International Conference on Harmonization (ICH Q2B) and USP. The method exhibited precision, robustness, accuracy, and selectivity. In accelerated stability testing over 6 months, no significant variations were observed in organoleptic analysis and pH. Consequently, the developed method is deemed suitable for routine quality control analyses, enabling the simultaneous determination of Sodium Lactate, Sodium Chloride, and Sorbitol in pharmaceutical formulations and infusions.

关键词： Sorbitol Sodium Lactate and Chloride Assay Analytical Validation HPLC

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Differences in both the structure and interaction of the crust and mantle on the eastern and western sides of the Ordos Block

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Science China Earth Sciences 2024年

作者： Yong CHEN Yifang CHEN Jiuhui CHEN Biao GUO Yu LI Panpan ZHAO State Key Laboratory of Seismic Dynamics Institute of GeologyChina Earthquake Administration National Field Scientific observatory for Continental Rift Valley Dynamics in Taiyuan Institute of Earthquake Forecasting China Earthquake AdministrationKey Laboratory for Earthquake Prediction

The Ordos Block, the western part of the North China Craton (NCC), has preserved most of its cratonic lithospheric roots during the destruction and modification of the NCC, and nowconnects two distinctly different tectonic units, i.e., the Tibetan Plateau (TP) to the west and the North China Plain to the east. It is important to studythe detailed crust-mantle structure of the Ordos Block and surroundings to understand the interactions between the Ordos and adjacent regions and the dynamics of the NCC evolution. In this study, the S-wave velocity structure at depths of 0–100 km along an E-W profile at around 36.5°N from the Qilian orogen (QLO) to the Trans-North China Orogen (TNCO) within the NCC was investigated by joint inversion of the receiver functions (RFs) and surface wave dispersion data from 104 broadband seismic stations deployed in the region under the ChinArray project (Phase Ⅱ and Phase Ⅲ). The image of discontinuity structures along the profile was further constructed by common conversion point stacking of RFs. The main results are as follows:(1) The depth of the Moho in the study region gradually decreases from west to east, being the deepest in the QLO, the second in the Ordos Block, and the shallowest in the TNCO. Local depression and uplift of the Moho are also identified beneath the Haiyuan fault zone and the Shanxi-Shaanxi rift system (SSR), respectively.(2) The crust-mantle structure displays obvious lateral heterogeneities among tectonic regions. A pronounced low-velocity anomaly is observed at depths of 20–40 km beneath the QLO and becomes weakened and thinned to the east, indicating that thickening of the mid-to-lower crust probably occurred in the QLO during the growth and lateral extrusion of the northeastern TP under the resistance of the NCC. The lithosphere-asthenosphere boundary beneath the TNCO is imaged at～90 km depth, which is significantly shallower than that beneath the Ordos *** observation suggests that the lithosphere of t

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Detection and analysis of landslide geomorphology based on UAV vertical photogrammetry

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Journal of Mountain Science 2024年第4期21卷 1190-1214页

作者： BI Rui GAN Shu YUAN Xiping LI Kun LI Raobo LUO Weidong CHEN Cheng GAO Sha HU Lin ZHU Zhifu School of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China Plication Engineering Research Center of Spatial Information Surveying and Mapping Technology in Plateau and Mountainous Areas Set by Universities in Yunnan Province Kunming 650093China West Yunnan University of Applied Sciences Key Laboratory of Mountain Real Scene Point Cloud Data Processing and Application for Universities in Yunnan ProvinceDali 671006China

High-resolution landslide images are required for detailed geomorphological analysis in complex topographic environment with steep and vertical landslide *** study proposed a vertical route planning method for unmanned aerial vehicles(UAVs),which could achieve rapid image collection based on strictly calculated route *** effectiveness of this method was verified using a DJI Mavic 2 Pro,obtaining high-resolution landslide images within the Dongchuan debris flow gully,in the Xiaojiang River Basin,Dongchuan District,Yunnan,China.A three-dimensional(3D)model was constructed by the structure-from-motion and multi-view stereo(SfM-MVS).Micro-geomorphic features were analyzed through visual interpretation,geographic information system(GIS),spatial analysis,and mathematical statistics *** results demonstrated that the proposed method could obtain comprehensive vertical information on landslides while improving measurement *** 3D model was constructed using the vertically oriented flight route to achieve centimeter-level accuracy(horizontal accuracy better than 6 cm,elevation accuracy better than 3 cm,and relative accuracy better than 3.5 cm).The UAV technology could further help understand the micro internal spatial and structural characteristics of landslides,facilitating intuitive acquisition of surface *** slope of landslide clusters ranged from 36°to 72°,with the majority of the slope facing east and *** elevation levels were relatively consistent while middle to lower elevation levels gradually decreased from left to right with significant variations in lower elevation *** the rainy season,surface runoff was abundant,and steep topography exacerbated changes in surface *** route method is suitable for unmanned aerial vehicle(UAV)landslide surveys in complex mountainous *** geomorphological analysis methods used will provide references for identifying and describing topographic

关键词： UAV Landslide Vertical route SfM-MVS Topographic features

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Stranched Internal Hernia Revealed by Occlusion of the Large Libra: A Propos of a Case

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Case Reports in Clinical Medicine 2024年第1期13卷 37-42页

作者： Abdoulaye Kanté Mamady Almami Kéita Idrissa Tounkara Drissa Ouattara Bréhima Bengaly Souleymane Sanogo Bréhima Togola Drissa Traoré Nouhoum Ongoiba General Surgery Department of The Kati-Mali Reference Health Center Koulikoro Mali Service of Surgery “B” of The CHU Du point G Faculty of Medicine and Odontostomatology Bamako Mali

The left para-duodenal internal hernia, whose origin is generally embryological, is a rare etiology of intestinal obstruction found mainly in young adults. We report here the case of acute intestinal obstruction by left para-duodenal internal hernia in a 36-year-old young man. It was a patient who consulted urgently for occlusive syndrome with cessation of materials and gases. Abdominal percussion noted abdominal tympanism and pre-hepatic dullness was preserved. The flow and icicle signs were negative. Palpation did not objectify hepatosplenomegaly and did not find any organomegaly either. On the other hand, she found an epigastric defense. The abdominal X-ray without preparation showed water levels that were wider than high, hail-like. We performed a median above and below umbilical laparotomy and intraoperatively, it was an internal hernia with incarceration of small loops in a voluminous left paraduodenal sac of 12 cm. They were not necrotic and quickly recolored after extrication. We resected the hernial sac and closed the hernial orifice with separate stitches with absorbable suture 0. The postoperative course was simple. The patient was discharged from the hospital on the 4th postoperative day. After 18 months of hindsight, he is doing well.

关键词： Paraduodenal Internal Hernia Occlusion Laparotomy

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How to Coadd Images.Ⅱ.Anti-aliasing and PSF Deconvolution

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Research in Astronomy and Astrophysics 2024年第4期24卷 103-113页

作者： Lei Wang Huanyuan Shan Lin Nie Dezi Liu Zhaojun Yan Guoliang Li Cheng Cheng Yushan Xie Han Qu Wenwen Zheng Xi Kang Purple Mountain observatory Chinese Academy of SciencesNanjing 210023China National Basic Science Data Center Beijing 100190China Zhejiang University-Purple Mountain observatory Joint Research Center for Astronomy Zhejiang UniversityHangzhou 310030China Shanghai Astronomical observatory Shanghai 200030China Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Information Engineering Wuhan Institute of CityWuhan 430083China South-Westem Institute for Astronomy Research Yunnan UniversityKunming 650500China The Shanghai Key Lab for Astrophysics.Shanghai Normal University Shanghai200234China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesCASBeijing 100101China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

We have developed a novel method for co-adding multiple under-sampled images that combines the iteratively reweighted least squares and divide-and-conquer *** approach not only allows for the anti-aliasing of the images but also enables point-Spread Function(PSF)deconvolution,resulting in enhanced restoration of extended sources,the highest peak signal-to-noise ratio,and reduced ringing *** test our method,we conducted numerical simulations that replicated observation runs of the China Space Station Telescope/the VLT Survey Telescope(VST)and compared our results to those obtained using previous *** simulation showed that our method outperforms previous approaches in several ways,such as restoring the profile of extended sources and minimizing ringing ***,because our method relies on the inherent advantages of least squares fitting,it is more versatile and does not depend on the local uniformity hypothesis for the ***,the new method consumes much more computation than the other approaches.

关键词： methods:analytical techniques:image processing gravitational lensing:weak (ISM:)cosmic rays

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Echocardiographic Aspects of Type 2 Diabetics Patients Hospitalized in the Medicine and Endocrinology Department of the Mali Hospital

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World Journal of Cardiovascular Diseases 2024年第3期14卷 129-139页

作者： Konaté Massama Mamadou Touré Mariam Sako Samba Sidibé Souleymane Mariko Djeneba Sylla Sow Elhaj Mahamane Maiga Coumba Adiaratou Thiam Youssouf Camara Hamidou Oumar Ba Asmao Keita Maiga Djenebou Traoré Zoumana Traoré Souleymane Coulibaly Bah Traoré Modibo Mariko Nouhoum Ouologuem Amadou Koné Ichaka Menta Faculty of Medicine and Dentistry Bamako USTTB Department of Medicine Hospital of Mali Bamako Mali Department of Cardiology CHU Gabriel TOURE Bamako Mali Department of Cardiology CHU point G Bamako Mali Department of Medicine Hospital of Timbuktu Bamako Mali Department of Cardiology Hospital of Kati Bamako Mali Department of Cardiology CHU Mother and Child Bamako Bamako Mali Department of Internal Medicine CHU point G Bamako Mali

Introduction: Cardiovascular disease is the leading cause of death in diabetics. The objective of our study was to investigate the echocardiographic aspects of type 2 diabetics. Patients and Method: Descriptive and cross-sectional study of 12 months from June 2020 to June 2021. We included hospitalized type 2 diabetics who underwent transthoracic cardiac ultrasound in the Department of Medicine and Endocrinology at the Mali Hospital. Results: We collected 128 type 2 diabetics. The predominance was male with a sex ratio of 1.2. The mean age of patients was 60.06 ± 11.54 years with extremes of 28 and 84 years. Echocardiographic abnormalities were dominated by abnormal relaxation of left ventricle in 62.5%, increased of left ventricle mass in 54.7% and left atrium dilation in 28.1%. Patients with type 2 diabetes mellitus and hypertension had more left atrium dilation with a p of 0.02. Disorders of global kinetics and systolic dysfunction were more prevalent in smoking patients with statistically significant associations, respectively, p = 0.02;p = 0.03. Dyslipidemia had a statistically significant association with segmental kinetic disorders with a p of 0.008. Duration of diabetes greater than 5 years was associated with left atrium dilation and p-value was 0.04. Conclusion: Diabetes is responsible for cardiovascular manifestations that can be identified with transthoracic echocardiography. Its performance in diabetic patients makes it possible to refine the patient’s management.

关键词： Diabetes Echocardiography Mali Hospital

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Nephroblastoma in Adults about a Clinical Case

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Surgical Science 2024年第2期15卷 81-88页

作者： Tounkara Cheickna Coulibaly Amara Malle Oumar Amadou Bréhima Bolo Coulibaly Bagoyoko Kaloga Daye Samake Hamidou Berthe Honoré Jean-Baptiste Gabriel Diakite Mamadou Lamine Department of General Surgery Hospital Center “Mother Child” Luxembourg Bamako Mali Directorate of Army Health Services Kati Mali Department of Urology and Andrology Point G University Hospital Bamako Mali

Nephroblastoma is the most common malignant renal tumor in children and is related to an abnormal proliferation of cells resembling those of the embryonic kidney (metanephroma), hence the terminology;embryonal tumor. These are tumors that remain and remain unstudied in Mali because they are common in adults in our context. Its annual incidence is estimated at approximately 1/10,000 births. Nephroblastoma is a rare or even exceptional tumor in adults. The clinical manifestation was a large swelling of the right hypochondrium;abdominal pain for a year;unquantified fever, hypertension, initial hematuria associated with burning during urination and anemia. The main clinical manifestation remained fever and abdominal pain. This renal tumor posed a diagnostic problem which was previously labeled as a mesenteric tumor in our general surgery department. The diagnosis was made by imaging: CT and magnetic resonance imaging. The treatment is multidisciplinary and combines chemotherapy, surgery with or without radiotherapy. The prognosis is poor due to late diagnosis and less effectiveness of chemotherapy compared to the child. Survival did not exceed a year and a half because the renal tumor in our patient was surgically overcome. We report a case of nephroblastoma in an 86-year-old patient with unfavorable histology (hematogenous metastases), operated on in the general surgery department and whose postoperative course was simple and who was referred to oncology for treatment.

关键词： Nephroblastoma Malignant Kidney Tumor Treatment Adult Mali

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Role of biochar in raising blue carbon stock capacity of salt marshes

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Pedosphere 2024年第1期34卷 19-22页

作者： Yuzhou HUANG Xi XIAO Ocean College Zhejiang UniversityZhoushan 316021China Key Laboratory of Marine Ecological Monitoring and Restoration Technologies of the Ministry of Natural Resources of China Shanghai 201306China Donghai Laboratory Zhoushan 316021China Ocean Academy Zhejiang UniversityZhoushan 316021China Key Laboratory of Watershed Non-point Source Pollution Control and Water Eco-security of Ministry of Water Resources College of Environmental and Resources SciencesZhejiang UniversityHangzhou 310058China

Salt marshes are an important blue carbon ecosystem, with surprisingly fast carbon accumulation rates that are 40 times higher than those of terrestrial forests. In recent decades, salt marshes have suffered great degradation and loss all over the world. The idea to enhance carbon stock in salt marshes(so-called blue carbon) using biochar (so-called black carbon) has recently been proposed. Although experiments and observations remain limited, significant enhancements in soil organic carbon and plant growth have been documented in most case studies. However, due to the limited number of observations and their relatively short time window ranging from months to less than one year, there still exists a knowledge gap regarding the process, mechanism, and effect of biochar in enhancing carbon stock in salt marshes. Future research is urgently needed in the following perspectives:1) exploring the relationship between carbon stock enhancement efficiency and biochar properties, 2) optimizing the physical and chemical properties of biochar to boost its efficiency, and 3)studying the in-situ responses of complex carbon pools to biochar addition, especially under tidal conditions and over a longer period of time.

关键词： soil stock char

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Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

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Research in Astronomy and Astrophysics 2024年第4期24卷 124-133页

作者： Xue-Mei Ye Da-Ming Wei Yi-Ming Zhu Zhi-Ping Jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China

AT2021lfa,also known as ZTF21aayokph,was detected by the Zwicky Transient Facility on 2021 May 4,a 05:34:48 ***-up observations were conducted using a range of ground-based optical telescopes,as wel as Swift/XRT and VLA ***2021lfa is classified as an“orphan afterglow”candidate due to its rapid flux decline and its reddened color(g-r=0.17±0.14 mag).For an optical transient source without promp gamma-ray detection,one key point is to determine its burst *** we measure the burst time through fitting the initial bump feature of AT2021lfa and obtain its burst time as 2021 May 3,at 22:09:50 *** afterglowpy,we model the multi-band afterglow of AT2021lfa and find that the standard model canno reproduce the late radio observations *** that the microphysical parameters ε_(e),ε_(B)(the energy fraction given to electrons and magnetic field),andξN(the fraction of accelerated electrons)may vary with time we then model the afterglow of AT2021lfa taking into account the temporal evolution of the physical parameters ε_(e),ε^(B),and ξ_(N) and find in this case the multi-wavelength observations can be reproduced *** initial Lorentz factor of AT2021lfa can be estimated from the peak time of the early afterglow,which yields a value of about 18 suggesting that AT2021lfa should be classified as a“dirty fireball.”From the upper limit for the prompt emission energy of AT2021lfa,we obtain that the radiation efficiency is less than 0.02%,which is much smaller than that of ordinary gamma-ray bursts(GRBs).It is also interesting that the fitted values of jet angle and viewing angle are very large,θ_(c)~0.66 rad,θ_(v)~0.53 rad,which may lead to the low Lorentz factor and radiation *** compared with GRB afterglow samples,it is evident that the onset bump timescale of AT2021lfa satisfies the empirical relationships observed in GRB ***,the luminosity of AT2021lfa falls within the range of observations for GRB samples;howeve

关键词： gamma-rays:ISM methods:numerical radiation mechanisms:non-thermal

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