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The rate of deadwood decomposition processes in tree stand gaps resulting from bark beetle infestation spots in mountain forests

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Forest Ecosystems 2024年第3期11卷 339-346页

作者： Ewa błonska adam Gorski Jarosław Lasota Department of Ecology and Silviculture Faculty of ForestryUniversity of Agriculture in Krakow29 Listopada 46 Str.31-425KrakowPoland

Decaying wood is an essential element of forest ecosystems and it affects its other components.The aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in the gaps formed in the montane forest stands.The research was carried out in the babiog orski National Park.The research plots were marked out in the gaps of the stands,which were formed as a result of bark beetle gradation.Control plots were located in undisturbed stands.The research covered wood of two species–spruce and beech in the form of cubes with dimensions of 50 mm×50 mm×22 mm.Wood samples were placed directly on the soil surface and subjected to laboratory analysis after 36 months.A significant influence of the wood species and the study plot type on the physicochemical properties of the tested wood samples was found.Wood characteristics strongly correlated with soil moisture.A significantly higher mass decline of wood samples was recorded on the reference study plots,which were characterized by more stable moisture conditions.Poorer decomposition of wood in the gaps regardless of the species is related to lower moisture.The wood species covered by the study differed in the decomposition rate.Spruce wood samples were characterized by a significantly higher decomposition rate compared to beech wood samples.Our research has confirmed that disturbances that lead to the formation of gaps have a direct impact on the decomposition process of deadwood.

关键词： bark beetle beech Decomposition rate Forest ecosystem mass decline Spruce Woody debris

Current concepts in the management of non-cirrhotic non-malignant portal vein thrombosis

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World Journal of Hepatology 2024年第5期16卷 751-765页

作者： adam J Willington Dhiraj Tripathi Department of Hepatology University Hospitals Birmingham NHS Foundation TrustBirmingham B152GWUnited Kingdom Department of Hepatology University Hospitals BirminghamBirmingham B152THUnited Kingdom

Non-cirrhotic non-malignant portal vein thrombosis(NCPVT)is an uncommon condition characterised by thrombosis of the portal vein,with or without extension into other mesenteric veins,in the absence of cirrhosis or intra-abdominal malignancy.Complications can include intestinal infarction,variceal bleeding and portal biliopathy.In this article,we address current concepts in the management of NCPVT including identification of risk factors,classification and treatment,and review the latest evidence on medical and interventional management options.

关键词： Non-cirrhotic portal vein thrombosis Portal vein mesenteric veins Venous thrombosis Portal hypertension

Rare earth-doped mixed Ni-Cu-Zn ferrites as an effective photocatalytic agent for active degradation of Rhodamine b dye

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Journal of Rare Earths 2024年第3期42卷 488-496,I0003页

作者： Swapnil A.Jadhav Sandeep b.Somvanshi Sudarshan S.Gawali Kranti Zakde K.m.Jadhav Department of Physics Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad431004MaharashtraIndia School of materials Engineering Purdue UniversityWest Lafayette 47906USA University Department of basic and Applied Sciences MGM UniversityAurangabad431003MaharashtraIndia

In this study, a series of Gd^(3+)-doped mixed Ni-Cu-Zn ferrites with composition of Zn_(0.5)Ni_(0.3)Cu_(0.2)Fe_(2-x)Gd_(x)O_(4)(x = 0, 0.025, 0.05, 0.075, 0.1) was prepared using self-ignition sol-gel method. The prepared nanoparticles with an average size ranging from 22 to 26 nm show a single-phase cubic structure belonging to the spinel matrix. A rise in the Gd^(3+)concentration leads to an increase in crystallite size and lattice parameter. In Fourier transform infrared spectra, two main absorption bands belonging to the spinel structure are observed. The high-frequency bands(v_(1)) represent the tetrahedral complex, while the lowfrequency bands(v_(2)) signify the octahedral complex. The optical bandgap of the nanoferrites is found within the range of 2.91 to 2.41 eV, depending on their size. The magnetic characteristics of the material,such as saturation magnetization and coercivity are significantly altered with the concentration of Gd^(3+)in the solution. Using Rhodamine b(Rhb) as a model organic pollutant, an in-depth investigation of the photocatalytic activity of the compounds was carried out. The present outcomes show that adding an adequate amount of Gd^(3+)significantly enhances the number of hydroxyl radicals produced by the ferrite,in turn, increasing the photocatalytic activity of the material. mechanism elucidated by scavenger studies reveals that ·OH and holes are the primary reactive radicals responsible for the degradation process.Prepared photocatalysts show an insignificant performance loss in five consecutive cycles. Thus, it is concluded that these photocatalysts are highly suitable for the remediation of dye-contaminated wastewater.

关键词： Gd^(3+)substitution Spinel ferrite Structural properties magnetic properties Photocatalysis Rare earths

Seroprevalence Survey of HIV and Hepatitis b Virus and behavioral Characteristics among Heavy Truck Drivers along Port Sudan-Khartoum Highways

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Open Journal of medical microbiology 2024年第1期14卷 11-22页

作者： Sara S. Osman adam A. mattar Omnia m. Hamid Faculty of Public Health Alzaiem Alazhari University Khartoum Sudan Faculty of medical Laboratory Sciences University of Medical Sciences & Technology Khartoum Sudan

The prevalence of human immunodeficiency virus (AIDS) and hepatitis b virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The present study aimed to screen for human immunodeficiency virus (HIV), hepatitis b virus (HbV), and behavioral characteristics among heavy truck drivers in Port Sudan. A cross-sectional study was conducted on 274 heavy truck drivers and their assistants who used the highway Port Sudan-Khartoum in Port Sudan city during 2019-2021. Data on behavioral characteristics and substance use habits were collected using a structured questionnaire, and an ELISA test was used to screen for HIV and HbV infections in the study participants. The chi-square test, odds ratio, and confidence intervals were used to find the association between behavioral characteristics and seropositive HIV/HbV. Of the 274 enrolled participants, the seroprevalence rates of HIV were 2.7% and HbV was 23.7%. Ninety-four (34.3%) of them had a history of high-risk sexual behavior outside of marriage;only two (0.7%) used condoms;14.2% of participants reported alcohol use;and 1.1% reported drug use. Univariate analysis revealed that having a sex history outside of marriage with ≥1 sex partner and never using a condom with a spouse or casual partner were significant risk factors for HIV and HbV among drivers. Fortunately, we found that most of the drivers reported low alcohol and drug use. Concerning this study, the seroprevalence of HIV and HbV is highly associated with a history of having sex outside of marriage and sexual behavior among truck drivers and assistances. Additional studies are needed to further investigate other STIs and behavioral characteristics associated with factors in truck drivers/assistance in different truck stop regions in Sudan.

关键词： Sexual Transmitted Infection Port Sudan Truck Drivers/Assistance

Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： m.b.KIRKHAm Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot be ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the moon or mars. This paper outlines the problems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could be done on Earth using both soils and plants. Results from such experiments could be used to grow plants when mankind establishes bases on the moon and mars.

关键词： soils soil bases

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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Chinese Physics b 2024年第5期33卷 204-211页

作者： Y.Lahlou b.maroufi m.Daoud LPHE-mS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPmS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum computation.Essentially,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum correlation.Nonetheless,this indistinguishability is no longer holds for mixed states.To contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum correlations.Our study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping process.this system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical modes.The key ingredient in analyzing quantum correlation in this system is the global covariance matrix.It forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,respectively.Our study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

Complexed amino acid minerals vs. bis-glycinate chelated minerals:Impact on the performance of old laying hens

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Animal Nutrition 2024年第1期16卷 395-408页

作者： marcos J.b.Santos maria C.m.m.Ludke Leandro m.Silva Carlos b.V.Rabello mércia R.barros Fabiano S.Costa Clariana S.Santos Jamille S.S.Wanderley Department of Animal Science Rural Federal University of Pernambuco Department of Veterinary Science Rural Federal University of Pernambuco

The present study was to evaluate the effect of trace minerals(Zn, mn, and Cu) from complexed amino acid minerals(ZmCAA) and bis-glycinate chelated minerals(ZmCGly) in laying hen diets on performance,internal and external egg quality, yolk mineral deposition, intestinal morphometry, and bone characteristics. From 78 to 98 weeks of age, 400 White LSL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per treatment. Treatments were distributed in a 2 ×2 factorial arrangement using either Zn, mn, and Cu of ZmCAA or ZmCGly source at 2 levels: low(20, 20,and 3.5 mg/kg of Zn, mn, and Cu, respectively) or high(40, 40, and 7 mg/kg of Zn, mn, and Cu,respectively). The analysis of variance was performed, and in cases where differences were observed, the means were compared using Tukey?s test(P mineral supplementation had a significant impact on the performance of laying hens. Hens fed ZmCAA had higher egg production(P = 0.01), egg weight(P = 0.02), egg mass(P = 0.01), and lower feed conversion ratio(P =0.05) compared to those fed ZmCGly. The ZmCAA supplementation showed higher albumen height(P =0.01), albumen weight(P = 0.01), and eggshell thickness(P mn(PmCAA. Tibia weight(P = 0.04)and bone densitometry(P bia were higher with ZmCAA supplementation. In the small intestine, ZmCAA resulted in longer villi(P = 0.02) and shorter crypt depth(P = 0.01) in the duodenum.Jejunum and ileum measurements were influenced by the level and source of trace minerals(P mCAA exhibited superior performance, egg quality, deposition of trace minerals in the egg yolk, and bone density compared to hens fed ZmCGly. In this study, older laying hens supplemented with ZmCAA at lower levels demonstrated adequate levels of supplementation.

关键词： bis-glycinates metal-amino acids Radiodensity Trace minerals

Direct microwave leaching conditions of rare earth elements in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.bilen b.birol m.N.Saridede S.S.Kaplan m.S.Sonmez Department of metallurgical and materials Engineering Yildiz Technical UniversityIstanbulTurkey Department of Chemical Engineering and materials Science Stevens Institute of TechnologyNew JereyUSA Department of metallurgical and materials Engineering Istanbul Technical UniversityIstanbulTurkey

The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s weight.It can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth oxides.In the present study,microwave leaching process was conducted to dissolve rare earth elements yttrium(Y),europium(Eu),and remaining rare earth elements(REEs)present in the phosphor powder of the fluorescent lamp.and the yields were compared.In the microwave leaching process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),sulphuric acid(H_(2)SO_(4))),acid concentration(0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)and reaction time(5-90 min)parameters on leaching efficiencies of varying rare earth elements and calcium were investigated.The highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),and 90 min.Activation energy calculations were made,and kinetic models of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum(La),cerium(Ce),and terbium(Tb)were examined to be chemical reaction controlled.moreover,calcium(Ca)and gadolinium(Gd)seem coherent with the mixed model.Concurrently,mathematical models of all experimental studies are created with the response surface box-behnken method and the correlation coefficients of all the models are over 90%.

关键词： Rare earth elements(REEs) Direct microwave leaching Fluorescent waste Kinetic models Response surface method

Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied mathematics and mechanics(English Edition) 2024年第1期45卷 197-216页

作者： C.G.PAVITHRA b.J.GIREESHA m.L.KEERTHI Department of PG Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India Department of mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTm) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTm) trihybrid nanofluid magnetic field