Combination of the experimental measurements of diffusion behavior and kinetic computational simulation provides a unique tool to probe the design of multi-component refractory alloys with excellent ...properties. In this work, for the first time, the determination of the interdiffusion coefficients of bcc phase in Mo-Zr system and Mo-Nb-Zr ternary system as well as the relevant atomic mobility parameters of Mo, Nb and Zr in BCC phase are investigated systematically. The interdiffusion coefficients of bcc phase in Mo-Zr binary alloys and Mo-Nb-Zr ternary alloys at 1423-1523 K were measured by solid-phase diffusion couple method combined with Boltzmann-Matano method and Matano-Kirkaldy method, respectively. Simultaneously, the quite steep Mo concentration gradients of the corresponding ternary diffusion couples in the Mo-Nb-Zr system are observed in this study, and the contributions of which are carefully evaluated in the subsequent extraction of the ternary interdiffusion coefficients for the Mo-Nb-Zr system. On the basis of the determined interdiffusion coefficients of Mo-Zr system and Mo-Nb-Zr system in this work, along with the relevant thermodynamic parameters, the atomic mobility parameters of Mo, Nb and Zr in BCC phase were evaluated, which are incorporated into the atomic mobility database of bcc phase in Nb-Mo-Ti-Zr multi-component system. In addition, the component distance curves of a series of diffusion couples are simulated by applying the established atomic mobility database. The consistency between the simulated results and the measured values further verifies the reliability of the work.
The Dandy–Walker malformation (DWM) is characterized by neuron dysregulation in embryonic development; however, the regulatory mechanisms associated with it are unclear. This study aimed to ...investigate the role of NADH dehydrogenase 1 alpha subcomplex 4 (NDUFA4) in regulating downstream signaling cascades and neuronal proliferation and apoptosis.
Ndufa4
overexpression promoted the proliferation of neurons and inhibited their apoptosis in vitro, which underwent reverse regulation by the
Ndufa4
short hairpin RNAs.
Ndufa4
-knockout (KO) mice showed abnormal histological alterations in the brain tissue, in addition to impaired spatial learning capacity and exploratory activity.
Ndufa4
depletion altered the microRNA expressional profiles of the cerebellum:
Ndufa4
inhibited miR-145a-5p expression both in the cerebellum and neurons. miR-145a-5p inhibited the proliferation of neurons and promoted their apoptosis.
Ndufa4
promoted and miR-145a-5p inhibited the expression of human homer protein homolog 1 and cyclin D2 in neurons. Thus,
Ndufa4
promotes the proliferation of neurons and inhibits their apoptosis by inhibiting miR-145a-5p, which directly targets and inhibits the untranslated regions of
Homer1
and
Ccnd2
expression.
The 87Sr/86Sr values for main-ore stage apatite (Ap2) and late-ore stage apatite (Ap3) at Badu, showing that the data plot between the Lower Cambrian basement rocks in the Youjiang basin.
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•Hydrothermal apatite is chemically (e.g., Cl, Mn) different from magmatic one at Badu.•Ore-forming fluids are mainly basement-sourced with deep magmatic input.•Basement input critical for Carlin-type Au mineralization in Youjiang basin.
The Paleozoic-Mesozoic Youjiang sedimentary basin in SW China is developed on a Lower Paleozoic low-grade metamorphic basement, and contains dozens of Carlin-type gold deposits with a total Au reserve of over 900 metric tonnes (t). Although most of these deposits are hosted in sedimentary rocks, ∼70% of the gold (∼24.5 t) in the Badu deposit is hosted in altered OIB-type dolerite. To date, the ore-fluid source of Carlin-type gold deposits in the basin is highly debated, hampering the formulation of genetic models. Here, for the first time, we present ore-related apatite chemical and Sr isotope compositions from the altered dolerite at Badu to provide new insight into the ore-fluid source of this key gold province.
Petrography studies distinguished three apatite generations (Ap1 to Ap3): Pre-ore Ap1 is needle-shaped or fine-grained (<20 μm), and occurs mainly in the unmineralized dolerite; Main-ore Ap2 is euhedral-subhedral coarse-grained (>100 μm) and spatially associated with auriferous pyrite and arsenopyrite in the mineralized dolerite; Late-ore Ap3 is also euhedral-subhedral coarse-grained (>100 μm), and hosted in quartz ± ankerite veins crosscutting the mineralized dolerite. Geochemically, Ap1 contains relatively high Cl (∼0.134 wt%), MnO (∼0.038 wt%), MgO (∼0.155 wt%), and SiO2 (∼0.285 wt%) contents, whereas Ap2 and Ap3 have relatively high SrO contents (∼0.448 and ∼0.45 wt%, respectively). This geochemical difference can be used to distinguish magmatic from hydrothermal apatite at Badu. Ap2 has similar chemistry to Ap3 except for the higher SO3 contents (up to ∼0.318 wt%), and they both have similarly higher 87Sr/86Sr ratios (0.709489–0.711787) than those of the unmineralized dolerite (0.706295–0.706323) and the sedimentary ore host in the basin, but similar to the Lower Cambrian basement rocks (0.70909–0.82733). This similarity indicates that the ore-forming fluids were dominantly sourced from the basinal basement or from deep magmatic fluids with radiogenic Sr addition from the basement rocks. The ore-forming fluids may also have leached MREEs from the sulfate-rich basement rocks, leading to the observed MREE enrichments in Ap2 and Ap3. Our study highlights that the basement material contribution is critical for the Carlin-type gold mineralization in the Youjiang basin.
The Jiangshan gold deposit is newly discovered gold deposit, and it is the largest in the Bengbu Uplift, with reserves of about 20 t. So its genesis haven’t been well investigated. Pyrite is the main ...gold-associated mineral in the Jiangshan gold deposit. The pyrite trace element reveal that Py4 has the highest gold content. Based on the texture of Py4, the Py4 formation related to tectonic event. And the tectonic event may be the most important factor in the mineralization of fracture-disseminated type gold deposit.
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•Jiangshan gold deposit comprised four stage. Py1, Py2, Py3, and Py4 formed in these four stages, respectively.•Stage Ⅳ was the main mineralization stage, during which enrichment and precipitation of gold were strongly affected by the associated tectonic event.•The narrow range (5.79–7.98‰) in the hydrothermal pyrite indicates that hydrothermal fluids were related to degassing of the mantle wedge metasomatized by slab fluids..•Jiangshan gold deposit is considered to be a fracture-disseminated-type gold deposit.
Many Phanerozoic gold deposits in East China, e.g., those in the Jiaodong Peninsula, hosted either in granitoids of the same age or Precambrian basement rocks of the North China Craton, have been well documented. The Bengbu Uplift along the southeastern margin of the North China Craton is believed to be the western extension of the Jiaodong gold province, separated by the large-scale sinistral Tan-Lu Fault Zone. However, no deposits with more than 10 t gold resources have been discovered in the Bengbu Uplift, and it is unclear whether the timing and genesis of gold deposits in the Bengbu Uplift are similar to those in the Jiaodong gold province.
In this study, laser ablation inductively coupled plasma mass spectrometry trace element analyses, mapping, and in situ sulfur isotope analyses were used to determine the source and process of gold mineralization in Jiangshan gold deposit, the largest in the region. The wall rocks in the Jiangshan gold deposit are metamorphic rocks of the Neo-Archaean Wuhe Group, and the ore bodies are controlled by the eastern part of the Guangou–Xiajijia Fault. Four stages were identified from cross-cutting relationships and textural and mineralogical characteristics: pre-ore stage (stage I), quartz–pyrite–muscovite alteration (stage II), pyrite–quartz veins (stage III), and quartz–pyrite veinlets (stage IV). Each of the four stages is characterized by a different type of pyrite, here named Py1, Py2, Py3 and Py4. Py1 formes the core of Py2, has elliptical and irregular shapes, contains low gold and arsenic concentrations, and has δ34S values of 0.86–2.86‰. Py2 is hosted in quartz–pyrite–muscovite-altered rocks with disseminated and aggregated euhedral to subhedral textures. It has elevated arsenic content and the lowest gold content, with some rhythmic zones and fractures. Stage II was crosscut by stage III. Py3 has anhedral textures with brittle deformation and occupies fractures in stage III pyrite–quartz veins. The gold content of Py3 is slightly higher than that of Py1 and Py2, but its arsenic content is extremely low. Py4 in the quartz–pyrite veinlets has cataclastic textures with the highest gold and chalcophile element contents. Native gold and electrum also formed in stage IV, which is the main gold stage in the Jiangshan deposit. The δ34S values of Py2–Py4 are broadly similar (5.79–7.98‰), suggesting a common sulfur source. Based on previous studies and higher δ34S values of hydrothermal pyrite, the fluid sulfur isotopes are interpreted to relate to degassing of the mantle wedge metasomatized by slab fluids during the westward subduction of the palaeo-Pacific plate beneath the North China Craton during the early Cretaceous. Based on the geological characteristics of the deposit, we classify the Jiangshan gold deposit as a Jiaodong fracture-disseminated-type gold deposit which occurs as disseminated veinlets and disseminated mineralization in wallrocks along fracture zones. Tectonic events may be the most important factor in gold mineralization in fracture-disseminated type gold deposits.
There were two stages of structure activity in the mining area. The pre-mineralisation structure activity formed F1 and F2 faults, and these faults also controlled location of the emplacement of ...Au-Cu mineralisation later. Subsequently, the intrusion related to gold and copper mineralisation was emplaced and released fluids, which formed K-Na silicate to illite-smectite altered magmatic-hydrothermal breccia, from the deep to shallow. Hydrothermal breccia with a high matrix/cement ratio then formed when mineralizing fluid permeated the fracture zone. During post-mineralisation activity, the sinistral strike-slip F1 and F2 faults were reactivated, forming tectonic breccia containing some massive carbonate ± quartz ± pyrite clusters clasts.
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•The Huangtun porphyry deposit is a newly discovered deposit in the Luzong Basin.•A sub-vertical breccia pipe hosted the main gold-copper mineralization.•Alteration varied from ab, bt-ab, chl and ser zones from deep to shallow.
Luzong Basin is an important part of the Middle-Lower Yangtze Metallogenic Belt in eastern China, in which the dominant types of deposits are iron-oxide-apatite and skarn iron deposits. However, a new porphyry gold-copper deposit, Huangtun deposit, has recently been discovered in the north-eastern margin of the basin. Detailed studies of geological characteristics and metallogenic processes of Huangtun gold-copper deposit are needed to supplement the mineralisation type of the Luzong Basin. Based on drill core logging and petrology observations of thin sections and polished sections, a north-striking sinistrial strike-slip major fault and a series of secondary NE-striking sinistrial strike-slip faults have been identified in the mining area. A mineralised breccia pipe at the intersection of the two groups of faults is the main host of the Au ore body. The alteration types in the mining area, from deep to shallow, include an albite alteration zone, a biotite-albite alteration zone, a chlorite alteration zone and a sericite-pyrite alteration zone. A detailed mapping of the breccia pipe has been provided in the mining area. Seven different breccias facies have been divided according to the internal structure, composition, morphology, matrix content and alteration assemblages. Genesis of the different breccia facies have been identified based on crosscutting relationships and clast-in-clast textures, which revealed that there are two different faulting and brecciation stages. During the first stage, matrix-supported breccia formed near the fracture zone. Gold-copper mineralisation then occurred along the intersection of the two groups of fracture zones, which formed K-Na silicate to sericite altered magmatic-hydrothermal breccia, from deep to shallow. In addition, these different facies of breccia correspond to four stages of fluid evolution: the albite stage, biotite-albite stage, chlorite stage and sericite-pyrite stage. Hydrothermal breccia with a high matrix/cement ratio then formed when mineralizing fluid permeated the fracture zone. During the second stage, the ore bodies were faulted to form tectonic breccia containing some massive carbonate ± quartz ± pyrite clusters as clasts. Based on the current study, we conclude that the locations of the intersection of fault zones in the northern part of the Luzong Basin and the northern part of the mining area have potential for further gold mineralisation.
The Chating deposit, located in Xuancheng ore district, is a newly discovered Cu-Au deposit in the Middle-Lower Yangtze River Metallogenic Belt (MLYB), eastern China; its genesis has not been well ...investigated. Mineral geochemistry of magnetite and biotite at Chating shows that there was a predominately magmatic fluid source, but addition of external fluids play an important role in potassic and skarn alteration. We conclude that Chating deposit shows affinities to a porphyry-type Cu-Au systems, but was affected by external fluids during its evolution.
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•Magmatic and hydrothermal minerals show distinct geochemistry characteristics.•Temperature, pressure and fO2 were changed from magma to hydrothermal fluids.•Mixing of magmatic with external fluids occurred in potassic and skarn alteration.•Chating has affinities to a porphyry-type Cu-Au system.
Porphyry deposits developed in intracontinental settings have some geological characteristics that differ from those developed in arc-related continental margins. The Chating deposit is a newly discovered Cu-Au deposit in the Middle-Lower Yangtze River Metallogenic Belt (MLYB), eastern China. We carried out detailed petrographic observations and major and trace element analyses of different types of magnetite and biotite from the host quartz diorite porphyry and different alteration zones in Chating to elucidate the genesis of Chating deposit.
Alteration types in Chating include skarn, sodic-calcic, potassic and phyllic, and copper mineralization is closely associated with potassic alteration of quartz diorite porphyry. The different types of magnetite and biotite at Chating show distinctive geochemical characteristics. Higher Ti and Al in magmatic magnetites and biotites compared to the hydrothermal minerals indicate higher temperature and pressure in the quartz diorite porphyry. Higher V in magmatic magnetites and lower XMg in magmatic biotites indicate higher fO2. Similar mineral geochemistry from typical worldwide porphyry deposits, for example, Al2O3, TiO2, FeOT, MgO, Na2O, IV(F) and IV(Cl) contents in biotite, and Ni/Cr, Ti, Al, Sn and Ga in magnetite, indicate a predominately magmatic fluid source. Differences in Si, Ca, Co/Ni, Mg, and Mn in different types of magnetite, and MnO, CaO, SiO2 differences in two types of biotite from typical porphyry copper deposits show the influence of external fluids. Moreover, high IV(F) values and low IV(Cl) values in biotites demonstrate that the magmatic-hydrothermal system in Chating was enriched in Cl and lacked F, consistent with the importance of Cl in the transport of Cu. Based on different discrimination diagrams for magnetite, such as Ni/Cr versus Ti, Ni/(Cr + Mn) versus Ti + V, and Al + Mn versus Ti + V, and the geochemical similarities of biotite from Chating and other porphyry deposits, combined with the similarity of alteration assemblages, we conclude that Chating has porphyry Cu-Au affinities, but the hydrothermal system was affected by external fluids, in contrast to more typical subduction-related porphyry deposits.
The deformation behavior in the U-Nb shape memory alloys (SMAs) is significantly sensitive to the aging effect, where the underlying mechanism remains unclear. In the present work, in-situ neutron ...diffraction is used to investigate simultaneously the macroscopic and microscopic stress-strain behaviors as well as the microstructure evolution in α″-martensitic U-Nb SMAs. The aging-effect-modulated mechanical properties are achieved through the modified twinning-detwinning process. The initial yielding strength is significantly increased from about 330 to 650 MPa at room temperature, while from approximately 440 to 700 MPa at 100 °C. The in-situ observations show that the strength enhancement arises from the aging-induced resistance during the twinning-detwinning process. High resolution neutron diffraction patterns indicate that the α″ phase structure is unchanged after aging. The aging effect is therefore understood by employing the defect migration mechanism, which explains well the enhanced yielding strength and twinning-detwinning resistance. It also suggests that the controllable properties could be realized by engineering the defect migration process and thus tuning the aging effect. These findings might shed some light on materials design and properties controlling for α″-martensitic U-Nb and other SMAs (e.g., Ni-Ti).
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•The strength enhancement is observed in the macro- and micro-scales for α″-martensitic U-Nb shape memory alloys.•The aging-induced twinning-detwinning resistance is revealed.•The aging effect can be well explained based on the defect-migration mechanism.•Controllable properties could be achieved by engineering the defect-migration process and thus tuning the aging effect.
•The mechanism of peeling tomatoes using HHAIB technology was investigated.•Peel cracking and loosening was observed from tomato epidermal tissues treated by HHAIB heating.•SEM, LSCM and TEM ...observation explained crack behaviors of tomato skin.•The water state and cell-wall polysaccharides changes of tomato fleshes explained peeling loosening.•HHAIB treatment increased the Young's Modulus of tomato skin making more likely to crack.
In order to better manage the peeling degree and avoid unnecessary losses, the current work aimed to explore the peeling mechanism of a novel peeling technology, high-humidity hot air impingement blanching (HHAIB). The relationships between HHAIB peeling performance and the changes in skin temperature, skin structure, water state, pectin fractions content, and skin mechanical properties of tomatoes were analyzed. Results showed, after HHAIB treatment, the epicuticular wax was disrupted, the skin exhibited more and longer random cracks, the degradation of inner skin tissue was observed by transmission electron microscopy, the free water percentage increased resulting in water loss in the whole tomato, the water-soluble pectin contents decreased in tomato fleshes, while the contents of chelate-soluble pectin and sodium-carbonate-soluble pectin increased. HHAIB heating reduced the elongation at break, and increased Young's Modulus of tomato peel. This study revealed the HHAIB peeling mechanism and provided new insights for developing HHAIB peeling technology.
Brucellosis is a severe zoonotic disease that is often overlooked, particularly in impoverished countries. Timely identification of focal complications in brucellosis is crucial for improving ...treatment outcomes. However, there is currently a lack of established indicators or biomarkers for diagnosing these complications. Therefore, this study aimed to investigate potential warning signs of focal complications in human brucellosis, with the goal of providing practical parameters for clinicians to aid in the diagnosis and management of patients.
A multi-center cross-sectional study was conducted in China from December 2019 to August 2021. The study aimed to investigate the clinical characteristics and complications of patients with brucellosis using a questionnaire survey and medical record system. The presence of warning signs for complications was assessed using univariate and multivariate logistic regression models. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used for variable screening and model evaluation.
A total of 880 participants diagnosed with human brucellosis were enrolled. The median age of the patients was 50 years interquartile range (IQR): 41.5-58.0, and 54.8% had complications. The most common organ system affected by complications was the osteoarticular system (43.1%), with peripheral arthritis (30.0%), spondylitis (16.6%), paravertebral abscess (5.0%), and sacroiliitis (2.7%) being the most prevalent. Complications in other organ systems included the genitourinary system (4.7%), respiratory system (4.7%), and hematologic system (4.6%). Several factors were found to be associated with focal brucellosis. These factors included a long delay in diagnosis odds ratio (OR) = 3.963, 95% confidence interval (CI) 1.906-8.238 for > 90 days, the presence of underlying disease (OR = 1.675, 95% CI 1.176-2.384), arthralgia (OR = 3.197, 95% CI 1.986-5.148), eye bulging pain (OR = 3.482, 95% CI 1.349-8.988), C-reactive protein (CRP) > 10 mg/L (OR = 1.910, 95% CI 1.310-2.784) and erythrocyte sedimentation rate (ESR) elevation (OR = 1.663, 95% CI 1.145-2.415). The optimal cutoff value in ROC analysis was > 5.4 mg/L for CRP (sensitivity 73.4% and specificity 51.9%) and > 25 mm/h for ESR (sensitivity 47.9% and specificity 71.1%).
More than 50% of patients with brucellosis experienced complications. Factors such as diagnostic delay, underlying disease, arthralgia, eye pain, and elevated levels of CRP and ESR were identified as significant markers for the development of complications. Therefore, patients presenting with these conditions should be closely monitored for potential complications, regardless of their culture results and standard tube agglutination test titers.
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