Summary
Experiments were performed to study the transformation, migration and outcome of residual bodies (RBs) in the seminiferous tubules of the rat testes. One part of the testes from adult ...Sprague–Dawley rats was used to generate paraffin sections to observe RBs and RB precursors through specific staining, and the other part of the testes was used to generate ultrathin sections to observe RBs under a transmission electron microscope. Deep blue particles of different sizes were observed in some seminiferous tubules through specific staining for RBs and RB precursors. These particles first appeared in the seminiferous tubules at stage I of the spermatogenic cycle, and after spermiation, the particles travelled rapidly towards the deeper region of the seminiferous epithelium and soon appeared close to the basement membrane of the seminiferous tubule. All of the particles in the tubules disappeared at stage IX. Using transmission electron microscopy, components of different electron densities were observed in the RBs on the surface of the seminiferous epithelium, all of which gradually formed in the cytoplasm of spermatozoon in later stages of spermiogenesis. After the spermatozoa were released, the RBs in the epithelium travelled quickly to the edge of the tube and were gradually transformed into lipid inclusions. These lipid inclusions ultimately became lipidlike particles. The lipidlike particles were discharged into the interstitial tissue. RBs initiate their own digestive process before their formation during spermiation in the rat testes. After spermiation, the RBs transform into lipid inclusions and finally into lipidlike particles. These lipidlike particles can be eliminated from the seminiferous tubules.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
We present X-ray timing results of the new black hole candidate MAXI J1535−571 during its 2017 outburst from Hard X-ray Modulation Telescope (Insight-HXMT) observations taken from 2017 September 6 to ...23. Following the definitions given by Belloni, we find that the source exhibits transitions from the low/hard state to the hard intermediate state, and eventually to the soft intermediate state. Quasi-periodic oscillations (QPOs) are found in the intermediate states, which suggest different types of QPOs. With the large effective area of Insight-HXMT at high energies, we are able to present the energy dependence of the QPO amplitude and centroid frequency up to 100 keV, which has rarely been explored by previous satellites. We also find that the phase lag at the type-C QPOs centroid frequency is negative (soft lag) and strongly correlated with the centroid frequency. Assuming a geometrical origin of type-C QPOs, the source is consistent with being a high-inclination system.
Abstract
The fast transitions between different types of quasi-periodic oscillations (QPOs) are generally observed in black hole transient sources (BHTs). We present a detailed study of the timing ...and spectral properties of the transitions of type-B QPOs in MAXI J1348–630, observed by Insight-HXMT. The fractional rms variability–energy relationship and energy spectra reveal that type-B QPOs probably originate from jet precession. Compared to a weak power-law dominated power spectrum, when type-B QPOs are present, the corresponding energy spectrum shows an increase in the Comptonization component and the need for the
xillverCp
component, and a slight increase in the height of the corona when using the
relxilllp
model. Therefore, we suggest that a coupled inner disk-jet region is responsible for the observed type-B QPO transitions. The timescale for the appearance/disappearance of type-B QPOs is either long or short (seconds), which may indicate instability of the disk-jet structure. For these phenomena, we hypothesize that the Bardeen–Petterson effect causes the disk-jet structure to align with the BH spin axis or that the disappearance of small-scale jets bound by the magnetic flux tubes leads to the disappearance of type-B QPOs. We observed three events regarding the B/C transitions, one of which occurred over a short time period from ∼9.2 Hz (C) to ∼4.8 Hz (B). The energy spectral analysis for the other two transitions shows that when type-C QPO is present, the Comptonization flux is higher, the spectrum is harder, and the inner radius of the disk changes insignificantly. We suggest that type-C QPOs probably originate from relatively stronger jets or the corona.
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•A new Cr(VI) adsorbent, phosphonium-crosslinked chitosan (PCC), was synthesized.•PCC had over double the adsorption capacity of chitosan at < 120 mg L−1 Cr(VI) at pH 6.•PCC is an ...effective adsorbent for Cr(VI) species over a broad pH range (pH = 4–10).•MgSO4 solution partially regenerates PCC without damaging the structure.
Adsorption is a commonly used method for industrial wastewater treatment because of its low-cost, easy operation and high efficiency. In this work, chitosan was crosslinked and functionalized with a low-cost phosphonium salt, tetrakis(hydroxymethyl)phosphonium sulfate (THPS), to enhance its adsorption capacity for Cr(VI). The novel phosphonium-crosslinked chitosan (PCC) was characterized using elemental analysis, XRF, FTIR, NMR and SEM-EDX. At pH 6, PCC had a higher Langmuir equilibrium constant than the unmodified chitosan (0.19 ± 0.02 L mg−1 versus 0.0044 ± 0.0005 L mg−1) and PCC demonstrated higher adsorption capacity than chitosan at equilibrium Cr(VI) concentrations below 120 mg L−1. Additionally, magnesium sulfate or magnesium chloride was shown to desorb Cr(VI) and recycle PCC. When treated with THPS, chitosan is activated for Cr(VI) adsorption at pH 6; therefore, PCC can be used in wastewater treatment over a wider pH range than chitosan.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Study question Can avian influenza A (H7N9) virus be transmitted between unrelated individuals in a hospital setting?Methods An epidemiological investigation looked at two patients who shared a ...hospital ward in February 2015, in Quzhou, Zhejiang Province, China. Samples from the patients, close contacts, and local environments were examined by real time reverse transcriptase (rRT) polymerase chain reaction (PCR) and viral culture. Haemagglutination inhibition and microneutralisation assays were used to detect specific antibodies to the viruses. Primary outcomes were clinical data, infection source tracing, phylogenetic tree analysis, and serological results.Study answer and limitations A 49 year old man (index patient) became ill seven days after visiting a live poultry market. A 57 year old man (second patient), with a history of chronic obstructive pulmonary disease, developed influenza-like symptoms after sharing the same hospital ward as the index patient for five days. The second patient had not visited any poultry markets nor had any contact with poultry or birds within 15 days before the onset of illness. H7N9 virus was identified in the two patients, who both later died. Genome sequences of the virus isolated from both patients were nearly identical, and genetically similar to the virus isolated from the live poultry market. No specific antibodies were detected among 38 close contacts. Transmission between the patients remains unclear, owing to the lack of samples collected from their shared hospital ward. Although several environmental swabs were positive for H7N9 by rRT-PCR, no virus was cultured. Owing to delayed diagnosis and frequent hospital transfers, no serum samples were collected from the patients, and antibodies to H7N9 viruses could not be tested.What this study adds Nosocomial H7N9 transmission might be possible between two unrelated individuals. Surveillance on patients with influenza-like illness in hospitals as well as chickens in live poultry markets should be enhanced to monitor transmissibility and pathogenicity of the virus.Funding, competing interests, data sharing Funding support from the Program of International Science and Technology Cooperation of China (2013DFA30800), Basic Work on Special Program for Science and Technology Research (2013FY114600), National Natural Science Foundation of China (81402730), Special Program for Prevention and Control of Infectious Diseases in China (2013ZX10004218), US National Institutes of Health (1R01-AI108993), Zhejiang Province Major Science and Technology Program (2014C03039), and Quzhou Science and Technology Program (20111084). The authors declare no other interests and have no additional data.
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BFBNIB, CMK, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Infection with parasitic helminths can imprint the immune system to modulate bystander inflammatory processes. Bystander or virtual memory CD8
T cells (T
) are non-conventional T cells displaying ...memory properties that can be generated through responsiveness to interleukin (IL)-4. However, it is not clear if helminth-induced type 2 immunity functionally affects the T
compartment. Here, we show that helminths expand CD44
CD62L
CXCR3
CD49d
T
cells through direct IL-4 signaling in CD8
T cells. Importantly, helminth-mediated conditioning of T
cells provided enhanced control of acute respiratory infection with the murid gammaherpesvirus 4 (MuHV-4). This enhanced control of MuHV-4 infection could further be explained by an increase in antigen-specific CD8
T cell effector responses in the lung and was directly dependent on IL-4 signaling. These results demonstrate that IL-4 during helminth infection can non-specifically condition CD8
T cells, leading to a subsequently raised antigen-specific CD8
T cell activation that enhances control of viral infection.
Graphene has emerged as a promising material for optoelectronics due to its potential for ultrafast and broad-band photodetection. The photoresponse of graphene junctions is characterized by two ...competing photocurrent generation mechanisms: a conventional photovoltaic effect and a more dominant hot-carrier-assisted photothermoelectric (PTE) effect. The PTE effect is understood to rely on variations in the Seebeck coefficient through the graphene doping profile. A second PTE effect can occur across a homogeneous graphene channel in the presence of an electronic temperature gradient. Here, we study the latter effect facilitated by strongly localised plasmonic heating of graphene carriers in the presence of nanostructured electrical contacts resulting in electronic temperatures of the order of 2000 K. At certain conditions, the plasmon-induced PTE photocurrent contribution can be isolated. In this regime, the device effectively operates as a sensitive electronic thermometer and as such represents an enabling technology for development of hot carrier based plasmonic devices.
ABSTRACT
We report on the Insight-HXMT observations of the new black hole X-ray binary MAXI J1820+070 during its 2018 outburst. Detailed spectral analysis via the continuum fitting method shows an ...evolution of the inferred spin during its high soft sate. Moreover, the hardness ratio, the non-thermal luminosity and the reflection fraction also undergo an evolution, exactly coincident to the period when the inferred spin transition takes place. The unphysical evolution of the spin is attributed to the evolution of the inner disc, which is caused by the collapse of a hot corona due to condensation mechanism or may be related to the deceleration of a jet-like corona. The studies of the inner disc radius and the relation between the disc luminosity and the inner disc radius suggest that, only at a particular epoch, did the inner edge of the disc reach the innermost stable circular orbit and the spin measurement is reliable. We then constrain the spin of MAXI J1820 + 070 to be $a_*=0.2^{+0.2}_{-0.3}$. Such a slowly spinning black hole possessing a strong jet suggests that its jet activity is driven mainly by the accretion disc rather than by the black hole spin.
Neutrophil infiltration is a key event in chronic intestinal inflammation and associated colorectal cancer, but how these cells support cancer development is poorly understood. In this study, using a ...mouse model of colitis-associated cancer (CAC), we have demonstrated that infiltrated neutrophils produce large amounts of interleukin-1 (IL)-1β that is critical for the development of CAC. Depletion of neutrophil or blockade of IL-1β activity significantly reduced mucosal damage and tumor formation. This protumorigenic function of IL-1β was mainly attributed to increased IL-6 secretion by intestine-resident mononuclear phagocytes (MPs). Furthermore, commensal flora-derived lipopolysaccharide (LPS) was identified to trigger IL-1β expression in neutrophils. Importantly, accumulation of IL-1β-expressing neutrophils was seen in lesions of patients suffering from ulceratic CAC and these infiltrated neutrophils induced IL-6 production by intestinal MPs in an IL-1β-dependent manner. Overall, these findings reveal that in CAC milieu, infiltrating neutrophils secrete IL-1β that promotes tumorigenesis by inducing IL-6 production by intestinal MPs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Plants deploy various immune receptors to recognize pathogens and defend themselves. Crosstalk may happen among receptor-mediated signal transduction pathways in the same host during simultaneous ...infection of different pathogens. However, the related function of the receptor-like kinases (RLKs) in thwarting different pathogens remains elusive. Here, we report that NIK1, which positively regulates plant antiviral immunity, acts as an important negative regulator of antibacterial immunity. nik1 plants exhibit dwarfed morphology, enhanced disease resistance to bacteria and increased PAMP-triggered immunity (PTI) responses, which are restored by NIK1 reintroduction. Additionally, NIK1 negatively regulates the formation of the FLS2/BAK1 complex. The interaction between NIK1 and FLS2/BAK1 is enhanced upon flg22 perception, revealing a novel PTI regulatory mechanism by an RLK. Furthermore, flg22 perception induces NIK1 and RPL10A phosphorylation in vivo, activating antiviral signalling. The NIK1-mediated inverse modulation of antiviral and antibacterial immunity may allow bacteria and viruses to activate host immune responses against each other.
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