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A two-layer (connected by stubs) partial composite plate is a structure with outstanding advantages which can be widely applied in many fields of engineering such as construction, transportation, and mechanical. However, studies are scarce in the past to investigate this type of structure. This paper is based on the new modified first-order shear deformation plate theory and finite element method to develop a new four-node plate element with nine degrees of freedom per node for static bending and vibration analysis of the two-layer composite plate. The numerical results are compared to published data for some special cases. The effects of some parameters such as the boundary condition, stiffness of the connector stub, height-to-width ratio, thickness-to-thickness ratio between two layers, and aspect ratio are also performed to investigate new numerical results of static bending and free vibration responses of this structure.

We study the Lagrange interpolation in ℝN and on the unit sphere in ℝN+1. It is shown that sequences of unisolvent sets can be combined to get other sequences of unisolvent sets such that the existence of the limits is preserved. Moreover, the limiting operators preserve the interpolation conditions in the process of combining. [ABSTRACT FROM AUTHOR]

We study the Lagrange interpolation in ℝN and on the unit sphere in ℝN+1. It is shown that sequences of unisolvent sets can be combined to get other sequences of unisolvent sets such that the existence of the limits is preserved. Moreover, the limiting operators preserve the interpolation conditions in the process of combining. [ABSTRACT FROM AUTHOR]

Bài báo trình bày các kết quả nghiên cứu quá trình dập vuốt biến mỏng thành vỏ liều đạn 40 mm NATO từ hợp kim đồng LK75. Mô đun Multiple-Operation của phần mềm thương mại Deform 2D được sử dụng cho bài toán mô phỏng nhiều bước trong quy trình công nghệ tạo hình. Mô hình vật liệu dẻo biến cứng được xây dựng bằng thí nghiệm thử kéo. Kết quả mô phỏng cho thấy, sự phân bố ứng suất và biến dạng không đồng đều trong sản phẩm sau dập vuốt biến mỏng thành. Đồng thời cho thấy sự tăng cường về ứng suất và biến dạng sau các bước dập vuốt biến mỏng thành. Ứng suất cao nhất là 650 MPa và 850 MPa tương ứng với bước dập vuốt biến mỏng thành số 4 và số 5. Biến dạng tương đương ở vị trí cách miệng bán sản phẩm 50 mm của bước 4 và bước 5 tương ứng là 0,528 (mm/mm) và 1,36 (mm/mm). Chính đặc điểm này của quá trình biến dạng nguội sẽ quyết định đến đặc điểm cơ tính của vỏ liều nhằm đáp ứng điều kiện hoạt động của chi tiết.

Abstract There is no reason why the gauge symmetry extension is family universal as in the standard model and the most well-motivated models, e.g. left-right symmetry and grand unification. Hence, we propose a simplest extension of the standard model – a flavor-dependent U(1) gauge symmetry – and find the new physics insight. For this aim, the U(1) charge, called X, is expressed as $$X=x B+y L$$ X = x B + y L in which x and y are free parameters as functions of flavor index, e.g. for a flavor i they take $$x_i$$ x i and $$y_i$$ y i respectively, where B and L denote normal baryon and lepton numbers. Imposing a relation involved by the color number 3, i.e. $$-x_{1,2,\ldots ,n}=x_{n+1,n+2,\ldots ,n+m}=3y_{1,2,\ldots ,n+m}\equiv 3z$$ - x 1 , 2 , … , n = x n + 1 , n + 2 , … , n + m = 3 y 1 , 2 , … , n + m ≡ 3 z , for arbitrarily nonzero z, we achieve a novel U(1) theory with implied X-charge. This theory not only explains the origin of the number of observed fermion families but also offers a possible solution for both neutrino mass and dark matter, which differs from $$B-L$$ B - L extension. Two typical models based on this idea are examined, yielding interesting results for flavor-changing neutral currents and particle colliders, besides those of neutrino mass and dark matter.

Abstract The $$SU(3)_L\otimes U(1)_X$$ S U ( 3 ) L ⊗ U ( 1 ) X symmetry actually studied is directly broken to the electroweak symmetry $$SU(2)_L\otimes U(1)_Y$$ S U ( 2 ) L ⊗ U ( 1 ) Y by a Higgs triplet, predicting a relevant new physics at TeV scale. This work argues, by contrast, that the higher weak isospin $$SU(3)_L$$ S U ( 3 ) L might be broken at a high energy scale, much beyond 1 TeV, by a Higgs octet to an intermediate symmetry $$SU(2)_L\otimes U(1)_{T_8}$$ S U ( 2 ) L ⊗ U ( 1 ) T 8 at TeV, before the latter $$U(1)_{T_8}$$ U ( 1 ) T 8 recombined with $$U(1)_X$$ U ( 1 ) X defines (i.e., broken to) $$U(1)_Y$$ U ( 1 ) Y by a Higgs singlet. The new physics coupled to $$SU(3)_L$$ S U ( 3 ) L breaking phase is decoupled, whereas what remains is a novel family-nonuniversal abelian model, $$U(1)_{T_8}\otimes U(1)_X$$ U ( 1 ) T 8 ⊗ U ( 1 ) X , significantly overhauling the standard model as well as yielding consistent results for neutrino mass, dark matter, W-mass anomaly, and FCNC, differently from the usual 3-3-1 model.

Abstract Quark has an electric charge either $$-1/3$$ - 1 / 3 or 2/3 and a baryon number 1/3, where the divisions 3’s match the color number. Although the electric charge and the baryon number have a nature distinct from the color charge, the matching is necessary for the standard model or a relevant $$B-L$$ B - L extension consistent at quantum level, since the relevant anomaly $$[SU(2)_L]^2U(1)_A$$ [ S U ( 2 ) L ] 2 U ( 1 ) A for $$A=Y$$ A = Y or $$B-L$$ B - L must vanish. If elementary particles have a new U(1) charge differently from A, such anomaly is not cancelled for each family. However, if we demand that the anomaly is cancelled over all families, this relates the color number to the family number instead of the electric charge and baryon number, and interestingly the family number guides us to a novel U(1) theory. We will discuss the implication of this theory for neutrino mass, recent W-boson mass anomaly, FCNC, and particle colliders.

Abstract Hedera nepalensis is commonly used as a traditional medicine for the treatment of several diseases. In this research, the efficient characterization of chemical constituents, especially triterpenoid saponins, contained in H. nepalensis extract was established by applying ultra‐high‐performance liquid chromatography‐quadrupole time‐of‐flight tandem mass spectrometry method (UHPLC‐Q‐TOF‐MS/MS). As a result, a total of 45 compounds including 21 triterpene saponins were tentatively elucidated based on MS and MS/MS data, in which eight structures have been reported for the first time. This study provided an efficient analysis strategy to rapidly determine the chemical constituents and laid a foundation for future study of H. nepalensis planted in Northern Vietnam and other Hedera species.

Abstract The recent precision measurement of the W-boson mass reveals an exciting hint for the new physics as of the 3-3-1 model. We indicate that the 3-3-1 model contains distinct sources by itself that may cause the W-mass deviation, as measured, such as the tree-level Z- $$Z'$$ Z ′ mixing, the tree-level W-Y and Z- $$Z'$$ Z ′ -X mixings, as well as the non-degenerate gauge vector (X, Y) and new Higgs doublets. We point out that the gauge vector doublet negligibly contributes to this mass shift, whereas the rest of the effects with tree-level mixings governed by Z- $$Z'$$ Z ′ and new Higgs doublets are significant. A discussion of scalar sextet contributions is also given.

Objectives: To translate and adapt the Diabetic Self-care Knowledge Questionnaire-30 (DSCKQ-30) questionnaire to be suitable for Vietnamese conditions and culture. To examine the reliability and validity of the Vietnamese version of the DSCKQ-30 questionnaire. Material and Methods: The questionnaire was forward translated, from English into Vietnamese and vice versa, by four independent translators. After that, an expert panel resolved any disagreements in translation regarding 4 criteria: semantics, idioms, experiences and concepts. The questionnaire then underwent a pilot study, on a sample of 100 DM patients to assess its clarity and readability; from June 1, 2021, to June 15, 2021. Finally, a test-retest study was conducted on a sample of 279 patients, over one month to examine internal consistency, stability and construct validity of the questionnaire; from July 1, 2021 to July 30, 2021. This study was approved by the Research Ethics Committee of the Thai Nguyen National Hospital. Results: The Vietnamese translated diabeté self-care knowledge questionnaire had content validity of 1.00, Cronbach’s alpha of 0.899 and Kappa coefficient of 0.700 or greater, except for question 15: with a Kappa coefficient of 0.658 (acceptable). Conclusion: The translated, adapted version of the DSCKQ-30 is valid, reliable and a feasible tool for practice, education and research in the future.

Sensors play an essential role in gathering environmental information for greenhouse farming. Wireless sensor network creates and manages links between sensor blocks in the system. As a result, not only various environmental parameters can be collected, but the sensor location can also be flexibly deployed. Sensor blocks require low energy consumption and inexpensive implementation costs with typical operating conditions. The research has built a wireless sensor network based on open Radio Frequency (RF) technology. Each sensor block has a low deployment cost and operates independently via a solar-powered unit. A novel communication protocol is designed for the proposed sensor network. In addition, a greenhouse controller exploiting designed wireless sensor networks is also constructed to evaluate the practicality of the system. Sensor networks developed are intended to be applied to the existing agricultural greenhouses in the surveyed area. The greenhouse is medium-sized, and the system implemented in practice is for vegetable farming. As a result, the controller can connect to the Internet to serve IoT links and applications. Experimental results prove the practicality of sensor blocks and the stability and efficiency of the wireless sensor network. It helps to reduce deployment costs and improve applicability. In addition, the sensor blocks are designed and built with low energy consumption, which can be operated with a small solar power source.

Since the electric charge in the standard model is theoretically not quantized, we may have a variant of it, called dark charge. Similar to the electric charge, the dark charge neither commutes nor closes algebraically with SU(2)L. The condition of algebraic closure leads to a novel gauge extension, SU(2)L⊗U(1)Y⊗U(1)N, where Y and N determine the electric and dark charges, respectively, apart from the color group. We argue that the existence of the dark charge, thus N, leads to novel scenarios of multi-component dark matter, in general. The dark matter stability is determined by a residual (or dark charge) gauge symmetry isomorphic to an even Zk discrete group, where k is specified dependent on the value of the neutrino dark charge. This residual symmetry divides the standard model particles into distinct classes, which possibly accommodate dark matter, but each dark matter candidate cannot decay due to the color and electric charge conservation. We analyze in detail three specific models according to k=2,4,6 and determine the simplest dark matter candidates. For small U(1)N coupling, the two-component dark matter scenarios implied by the dark charge successfully explain the dark matter relic density and the recent XENON1T excess, as well as the beam dump, neutrino scattering, and astrophysical bounds. Otherwise, for large U(1)N coupling, we have multi-WIMPs coexisted beyond the weak scale.

We construct new Hermite interpolation schemes in $${\mathbb{R}^2}$$ , and Lagrange and Hermite interpolation schemes on the unit sphere in $${\mathbb{R}^3}$$ . We show that the Hermite projectors in $${\mathbb{R}^2}$$ are the limits of Lagrange projectors at Bos configurations distributed on lines and circles in $${\mathbb{R}^2}$$ . Using this result we prove that the Lagrange projectors on the unit sphere converge to the Hermite projectors when the interpolation points coalesce. [ABSTRACT FROM AUTHOR]

Abstract We present the features of the fully flipped 3-3-1-1 model and show that this model leads to dark matter candidates naturally. We study two dark matter scenarios corresponding to the triplet fermion and singlet scalar candidates, and we determine the viable parameter regimes constrained from the observed relic density and direct detection experiments.

Abstract The present matter content of our universe may be governed by a $$U(1)_{B-L}$$ U ( 1 ) B - L symmetry – the simplest gauge completion of the seesaw mechanism which produces small neutrino masses. The matter parity results as a residual gauge symmetry, implying dark matter stability. The Higgs field that breaks the $$B-L$$ B - L charge inflates the early universe successfully and then decays to right-handed neutrinos, which reheats the universe and generates both normal matter and dark matter manifestly.

Abstract We argue that neutrino mass and dark matter can arise from an approximate B − L symmetry. This idea can be realized in a minimal setup of the flipped 3-3-1 model, which discriminates lepton families while keeping universal quark families and uses only two scalar triplets in order for symmetry breaking and mass generation. This proposal contains naturally an approximate non-Abelian B − L symmetry which consequently leads to an approximate matter parity. The approximate symmetries produce small neutrino masses in terms of type II and III seesaws and may make dark matter long lived. Additionally, dark matter candidate is either unified with the Higgs doublet by gauge symmetry or acted as an inert multiplet. The Peccei-Quinn symmetry is discussed. The gauge and scalar sectors are exactly diagonalized. The signals of the new physics at colliders are examined.

Abstract It is well established that the SU(P)L gauge symmetry for P ≥ 3 can address the question of fermion generation number due to the anomaly cancellation, but it neither commutes nor closes algebraically with electric and baryon-minus-lepton charges. Hence, two U(1) factors that determine such charges are required, yielding a complete gauge symmetry, SU(P)L ⊗ U(1)X ⊗ U(1)N, apart from the color group. The resulting theory manifestly provides neutrino mass, dark matter, inflation, and baryon asymmetry of the universe. Furthermore, this gauge structure may present kinetic mixing effects associated to the U(1) gauge fields, which affect the electroweak precision test such as the ρ parameter and Z couplings as well as the new physics processes. We will construct the model, examine the interplay between the kinetic mixing and those due to the symmetry breaking, and obtain the physical results in detail.

Abstract The flipped 3-3-1 model discriminates lepton families instead of the quark ones in normal sense, where the left-handed leptons are in two triplets plus one sextet while the left-handed quarks are in antitriplets, under SU(3) L . We investigate a minimal setup of this model and determine novel consequences of dark matter stability, neutrino mass generation, and lepton flavor violation. Indeed, the model conserves a noncommutative B−L symmetry, which prevents the unwanted vacua and interactions and provides the matter parity and dark matter candidates that along with normal matter form gauge multiplets. The neutrinos obtain suitable masses via a type I and II seesaw mechanism. The nonuniversal couplings of Z′ with leptons govern lepton flavor violating processes such as μ → 3e, μ → e ν ¯ $$ \overline{\nu} $$ μ ν e , μ-e conversion in nuclei, semileptonic τ → μ(e) decays, as well as the nonstandard interactions of neutrinos with matter. This Z′ may also set the dark matter observables and give rise to the LHC dilepton and dijet signals.

Anoectochilus formosanus Hayata is an important medicinal plant with various pharmaceutical properties. In this study, A. formosanus plants were hydroponically cultivated in different nutrient solutions to achieve enhanced biomass and secondary metabolites production. Three months-old A. formosanus plants were grown for 8 weeks under controlled environment in plastic pots containing Murashige and Skoog (MS), Nitrophoska Foliar (NF), Hydro Green (HG), or Hydro Bee (HB) media. Among 4 nutrient solutions tested, HB was the most efficient medium for the plant growth with the highest fresh weight (FW, 2.56 g/plant) and dry weight (DW, 0.18 g/plant) values. The results of phytochemical screening showed the presence of alkaloids, flavonoids, terpenoids, glycosides, and steroids in the extracts of A. formosanus cultivated in HB, HG, and MS medium. The level of these compounds was significantly different in plants cultivated in tested media. The highest alkaloids (34.87 μg/g DW) and terpenoids (56.43 μg/g DW) contents were obtained on HG medium, whereas flavonoids were present in highest amounts (90.13 μg QE/g DW) in plants grown in NF medium. On the other hand, HB medium stimulated the production of the highest glycoside (64.33 μg/g DW) and steroids (22.83 μg/g DW) levels. The antioxidant activity of the extracts was also tested using the 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) scavenging activity assay and the results demonstrated strong antioxidant activities of A. formosanus extracts with IC 50 of 136.19 to 248.85 μg/ml. Concluding, the hydroponic-cultivation of A. formosanus is a promising way for obtaining highly valuable compounds for pharmaceutical and nutraceutical industries.

Oxygen consumption rate (OCR) of muscle fibers from bovine semimembranosus muscle of 41 animals was investigated 3 to 4 h and 3 wk postmortem. Significant relations (P < 0.05) were found between OCR measurements and Warner-Bratzler shear force measurement. Muscles with high mitochondrial OCR after 3 to 4 h and low nonmitochondrial oxygen consumption gave more tender meat. Tender (22.92 ± 2.2 N/cm2) and tough (72.98 ± 7.2 N/cm2) meat samples (4 samples each), separated based on their OCR measurements, were selected for proteomic studies using mitochondria isolated approximately 2.5 h postmortem. Twenty-six differently expressed proteins (P < 0.05) were identified in tender meat and 19 in tough meat. In tender meat, the more prevalent antioxidant and chaperon enzymes may reduce reactive oxygen species and prolong oxygen removal by the electron transport system (ETS). Glycolytic, Krebs cycle, and ETS enzymes were also more abundant in tender meat. [ABSTRACT FROM AUTHOR]

This work is the first exploration of the static bending and dynamic response analyses of piezoelectric bidirectional functionally graded plates by combining the third-order shear deformation theory of Reddy and the finite element approach, which can numerically model mechanical relations of the structure. The present approach and mechanical model are confirmed through the verification examples. The geometrical and material study is conducted to evaluate the effects of the feedback coefficients, volume fraction parameter, and constraint conditions on the static and dynamic behaviors of piezoelectric bidirectional functionally graded structures, and this work presents a wide variety of static and dynamic behaviors of the plate with many interesting results. There are many meanings that have not been mentioned by any work, especially the working performance of the structure is better than that when the feedback parameter of the piezoelectric component is added, that is, the piezoelectric layer increases the working efficiency. Numerical investigations are the important basis for calculating and designing related materials and structures in technical practice.

Giáp xác là nhóm loài có giá trị kinh tế trong hệ sinh thái rạn san hô, tuy nhiên, danh mục thành phần loài đến nay vẫn chưa được cập nhật đầy đủ. Nghiên cứu này nhằm đánh giá và cập nhật đa dạng thành phần loài giáp xác trong rạn san hô ven bờ và ven đảo Việt Nam. Dự án I.2 được thực hiện trong các năm 2010, 2011và 2015, dự án I.8 được thực hiện năm 2015 và 2016, hai dự án I.2 và I.8 đã khảo sát lặn SCUBA và thu thập mẫu vật giáp xác. Kết quả đã xác định được 106 loài giáp xác của 45 giống thuộc 23 họ trong 02 bộ của ngành phụ Crustacea. Trong đó, có 55 loài trong rạn san hô ven bờ và 92 loài trong rạn san hô ven đảo. Từ nghiên cứu này, (năm 2020) tên khoa học của 23 loài đã đươc cập nhật và hiệu chỉnh theo hệ cơ sở dữ liệu đa dạng sinh học toàn cầu. Chỉ số tương đồng Sorensen giữa các vùng rạn san hô ven bờ dao động trong khoảng từ 0,04 - 0,70 và vùng rạn san hô ven đảo trong khoảng 0,61- 0,93. Chỉ số đa dạng loài giáp xác (H’) của vùng rạn san hô ven bờ và ven đảo đạt mức trung bình lần lượt là 1,41 và 0,83. Trong số này, 09 loài đã được xác định có giá kinh tế cao phục vụ cho việc quy hoạch vùng nuôi.

This paper carries out an experimental study to enhance the quality of the characteristic transmittance curve in the infrared range of 2.5–7 µm of the optical magnesium fluoride (MgF2) ceramic. This work evaluates the effectiveness of using vacuum environment in the MgF2 ceramic hot-pressing technique by comparing the density and the quality of the transmittance characteristic curve of two types of specimens manufactured by the hot-pressing technique corresponding to open air and vacuum environment under the same technological parameters including temperature 650°C, time 30 min, and pressure 200 MPa. The results present that, in comparison with using the hot-pressing technique in the open air, when using the hot-pressing technique in a vacuum environment, the transmittance increases about 4–10%, the characteristic transmittance curve is smoother and has fewer peak points, and the wide of peak points are smaller. When hot-pressing in a vacuum environment, the temperature can be up to 750°C in order to obtain the magnesium fluoride (MgF2) ceramic with the highest quality of characteristic line in the infrared range of 2.5–7 µm. Seventeen specimens are manufactured to conduct the experimental study in order to figure out the optimal set of technological parameters (temperature T = 640.9°C, time t = 33.0 min, and pressure P=231.4 MPa) when hot-pressing in a vacuum environment by the experimental planning approach.

Interpretations of seismic, gravity and magnetic anomalies and structural data on the coastal zone of southern part of Central Viet Nam (SCVN) and the adjacent Tertiary basins suggest several phases in the tectonic evolution of the study region since the Late Cretaceous to Quaternary. In this paper, we try to clarify the tectonic evolution of SCVN and the adjacent continental margin. The Cretaceous – Paleocene tectonic phase commenced after cessation of the West Pacific plutonic magmatic activity that produced numerous diabases and aplite dykes of mainly sub-meridian orientation. It was characterized by N–S compression and E–W extension. The geomorphology and geology ofSE Asiawere considerably changed during the Neotectonic phases caused by collision between the Indian plate and the Eurasian continent. Two tectonic phases – Early and Late Neotectonic – are separated by a regional unconformity represented by a boundary surface between below strongly deformed strata (synrift) and above less deformed formations (post-rift). The Early Neotectonic phase was related to the left-lateral movement of the Red River Fault Zone (RRFZ) and includes two tectonic sub-phases: Eocene – Oligocene (NW–SE compression), and Oligocene – Miocene (E–W compression). Activity in the Oligocene-Miocene sub-phase gave birth to rift basins in the continental margin of the SCVN. The Late Neotectonic phase began since the RRFZ stopped left-lateral movement and the East Viet Nam (orSouth China) Sea stopped spreading. The Late Neotectonic phase is also divided into two tectonic sub-phases: Late Early Miocene (sub-meridian compression), and Late Miocene – Pliocene (NE–SW compression). The Late Miocene – Pliocene sub-phase is characterized by vertical movements that caused episodic uplifting of the onland terrains, and subsidence of the offshore Phu Khanh basin. Besides, Miocene – Pliocene-Quarternary basaltic eruptions were widespread all over the southern Indosinian terrain and the continental margin.

The accessibility of pores to methane has been investigated in Devonian New Albany Shale Formation early-mature (Ro = 0.50%) to post-mature (Ro = 1.40%) samples. A Marcellus Shale Formation sample was included to expand the maturation range to Ro 2.50%. These are organic matter-rich rocks with total organic carbon (TOC) values of 3.4 to 14.4% and porosity values of 2.19 to 6.88%. Contrast matching small-angle neutron scattering (SANS) and ultra-small angle neutron scattering (USANS) techniques were used to generate porosity-related data before and after pressure cycling under hydrostatic (in a vacuum and at 500 bar of deuterated methane) and uniaxial stress (0 to ca. 350 bar) conditions. Our results showed that the accessible porosity was small for the samples studied, ranging from zero to 2.9%. No correlation between the accessible porosity and TOC or mineralogical composition was revealed, and the most likely explanation for porosity variation was related to the thermal transformation of organic matter and hydrocarbon generation. Pressure caused improvements in accessible porosity for most samples, except the oil window sample (Ro = 0.84%). Our data show that densification of methane occurs in nanopores, generally starting at diameters smaller than 20 nm, and that the distribution of methane density is affected by pressure cycling.