Nanometer-thick passive films, which impart superior corrosion resistance to metals, are degraded in long-term service; they are also susceptible to chloride-induced localized attack. Here we show, ...by engineering crystallographic configurations upon metal matrices adjacent to their passive films, we obtain great enhancement of corrosion resistance of FeCr15Ni15 single crystal in sulphuric acid, with activation time up to two orders of magnitude longer than that of the non-engineered counterparts. Meanwhile, engineering crystallography decreases the passive current density and shifts the pitting potential to noble values. Applying anodic polarizations under a transpassivation potential, we make the metal matrices underneath the transpassive films highly uneven with {111}-terminated configurations, which is responsible for the enhancement of corrosion resistance. The transpassivation strategy also works in the commercial stainless steels where both grain interior and grain boundaries are rebuilt into the low-energy configurations. Our results demonstrate a technological implication in the pretreatment process of anti-corrosion engineering.
An anomaly in differential scanning calorimetry has been reported in a number of metallic glass materials in which a broad exothermal peak was observed between the glass and crystallization ...temperatures. The mystery surrounding this calorimetric anomaly is epitomized by four decades long studies of Pd-Ni-P metallic glasses, arguably the best glass-forming alloys. Here we show, using a suite of in situ experimental techniques, that Pd-Ni-P alloys have a hidden amorphous phase in the supercooled liquid region. The anomalous exothermal peak is the consequence of a polyamorphous phase transition between two supercooled liquids, involving a change in the packing of atomic clusters over medium-range length scales as large as 18 Å. With further temperature increase, the alloy reenters the supercooled liquid phase, which forms the room-temperature glass phase on quenching. The outcome of this study raises a possibility to manipulate the structure and hence the stability of metallic glasses through heat treatment.
The fundamental problem of corneal transplantation is a severe shortage of donor tissues worldwide, resulting in approximately 1.5 million new cases of blindness annually. To explore an alternative ...to donor corneas, we conducted a clinical study in which implanted acellular porcine corneal stromas (APCSs) replaced the pathologic anterior corneas in 47 patients who had experienced fungal corneal infections. Subsequently, we demonstrated the safety and efficacy of APCSs in human keratoplasty for a minimum follow‐up period of 6 months, during which time no recurrence of infection was observed. All corneal ulcers healed with the return of neovascularization. In addition, our results indicated that epithelialization occurred in all APCS grafts except four grafts; for these four, the grafts dissolved to varying degrees. Furthermore, most porcine grafts (n = 41) gradually became transparent without rejection, and an improvement of more than two lines in best corrected visual acuity (BCVA) was achieved in 34 eyes (∼72%). Finally, no patients showed any severe adverse reaction or any significant change in postoperative systemic safety indicators. Thus, we concluded that APCS grafts are safe and efficacious during lamellar keratoplasty in treating corneal fungal ulcers and potentially for other clinical diseases.
This study demonstrates the safety and efficacy of acellular porcine cornea stroma as an alternative to donor corneas through lamellar keratoplasty treatment of corneal fungal ulcers.
Socioeconomic status (SES) and bilingualism have been shown to influence executive functioning during early childhood. Less is known, however, about how the two factors interact within an individual. ...By analyzing a nationally representative sample of approximately 18,200 children who were tracked from ages 5 to 7 across four waves, both higher SES and bilingualism were found to account for greater performance on the inhibition and shifting aspects of executive functions (EF) and self‐regulatory behaviors in classroom. However, only SES reliably predicted verbal working memory. Furthermore, bilingualism moderated the effects of SES by ameliorating the detrimental consequences of low‐SES on EF and self‐regulatory behaviors. These findings underscore bilingualism's power to enrich executive functioning and self‐regulatory behaviors, especially among underprivileged children.
With the aim of exploring the potential application of a novel chitosan oligosaccharide derivative (COS‐All‐Tio) in shrimp preservation, six dominant spoilage bacteria in the spoiled shrimp (Penaeus ...vannamei) were isolated and identified as Shewanella putrefaciens (RMS1), S. putrefaciens (S2), Pseudomonas weihenstephanensis (P1), P. gessardii (P2), Aeromonas bestiarum (A1) and Aeromonas molluscorum (A2). The antibacterial effect of COS‐All‐Tio against the six bacterial isolates were studied. Bacterial inhibition zone determination, and minimum inhibitory concentration and minimum bactericidal concentration assays indicated that the antibacterial activity of COS‐All‐Tio was greatly improved when compared to that of chitosan oligosaccharide (COS). The antibacterial mechanism investigation against S. putrefaciens (RMS1) revealed that COS‐All‐Tio could inhibit bacterial growth by influencing of membrane integrity. Such disturbance of membrane structure resulted in the leakage of intracellular substance of the bacteria. A strong synergistic antibacterial effect against S. putrefaciens (RMS1) was observed when COS‐All‐Tio was used in combination with food preservatives (e.g. ε‐polylysine hydrochloride). Therefore, COS‐All‐Tio might have potential in shrimp preservation.
Significance and Impact of the Study: To explore the potential application of a novel chitosan oligosaccharide derivative (COS‐All‐Tio) in shrimp preservation, its antibacterial activity against six dominant spoilage bacteria isolated from shrimp were investigated. The antibacterial mechanism investigation against the most potent spoilage bacteria, Shewanella putrefaciens (RMS1), was also studied. A strong synergistic antibacterial effect against RMS1 was observed when COS‐All‐Tio was used in combination with ε‐polylysine hydrochloride. Therefore, COS‐All‐Tio might have potential in shrimp preservation.
Functional, tumor-specific CD8
cytotoxic T lymphocytes drive the adaptive immune response to cancer. Thus, induction of their activity is the ultimate aim of all immunotherapies. Success of ...anti-tumor immunotherapy is precluded by marked immunosuppression in the tumor microenvironment (TME) leading to CD8
effector T cell dysfunction. Among the many facets of CD8
T cell dysfunction that have been recognized-tolerance, anergy, exhaustion, and senescence-CD8
T cell senescence is incompletely understood. Naïve CD8
T cells require three essential signals for activation, differentiation, and survival through T-cell receptor, costimulatory receptors, and cytokine receptors. Downregulation of costimulatory molecule CD28 is a hallmark of senescent T cells and increased CD8
CD28
senescent populations with heterogeneous roles have been observed in multiple solid and hematogenous tumors. T cell senescence can be induced by several factors including aging, telomere damage, tumor-associated stress, and regulatory T (Treg) cells. Tumor-induced T cell senescence is yet another mechanism that enables tumor cell resistance to immunotherapy. In this paper, we provide a comprehensive overview of CD8
CD28
senescent T cell population, their origin, their function in immunology and pathologic conditions, including TME and their implication for immunotherapy. Further characterization and investigation into this subset of CD8
T cells could improve the efficacy of future anti-tumor immunotherapy.
Summary
Background
Coronavirus disease 2019 (COVID-19) is a global pandemic but the follow-up data of discharged patients was barely described.
Aim
To investigate clinical outcomes, distribution of ...quarantine locations and the infection status of the contacts of COVID-19 patients after discharge.
Design
A prospective cohort study.
Methods
Demographics, baseline characteristics of 131 COVID-19 patients discharged from 3 February 2020 to 21 February 2020 in Wuhan, China were collected and analyzed by reviewing the medical records retrospectively. Post-hospitalization data related to clinical outcomes, quarantine locations and close contact history were obtained by following up the patients every week up to 4 weeks.
Results
Fifty-three (40.05%) patients on discharge had cough (29.01%), fatigue (7.63%), expectoration (6.11%), chest tightness (6.11%), dyspnea (3.82%), chest pain (3.05%) and palpitation (1.53%). These symptoms constantly declined in 4 weeks post-discharge. Transient fever recurred in 11 (8.4%) patients. Among the discharged patients, 78 (59.5%) underwent chest CT and 2 (1.53%) showed deterioration. A total of 94 (71.8%) patients received SARS-CoV-2 retest and 8 (6.10%) reported positive. Seven (2.29%) patients were readmitted because of fever or positive SARS-CoV-2 retest. After discharge, 121 (92.37%) and 4 (3.05%) patients were self-quarantined at home or community spots, respectively, after a close contact with 167 persons in total who were free of COVID-19 at the endpoint of study.
Conclusion
The majority of COVID-19 patients after discharge were in the course of recovery. Readmission was required in rare cases due to suspected recurrence of COVID-19. Although no contacted infection observed, appropriate self-quarantine and regular re-examination are necessary, particularly for those who have recurred symptoms.
Conductivities are key material parameters that govern various types of transport (electronic charge, spin, heat and so on) driven by thermodynamic forces. Magnons, the elementary excitations of the ...magnetic order, flow under the gradient of a magnon chemical potential1–3 in proportion to a magnon (spin) conductivity. The magnetic insulator yttrium iron garnet is the material of choice for efficient magnon spin transport. Here we report a giant magnon conductivity in thin yttrium iron garnet films with thicknesses down to 3.7 nm when the number of occupied two-dimensional subbands is reduced from a large number to a few, which corresponds to a transition from three-dimensional to two-dimensional magnon transport. We extract a two-dimensional magnon spin conductivity around 1 S at room temperature, comparable to the (electronic) conductivity of the high-mobility two-dimensional electron gas in GaAs quantum wells at millikelvin temperatures4. Such high conductivities offer opportunities to develop low-dissipation magnon-based spintronic devices.The authors report the observation of an enhanced magnon conductivity close to the two-dimensional transport regime in ultrathin yttrium iron garnet.
The aim of this study was to evaluate and aggregate the evidence from the published studies to determine the effectiveness of intradiscal steroid injection (ISI) in patients with symptomatic Modic ...type I change (MCI).
A systematic literature search was independently performed by two authors. The electronic database, including PubMed, Embase, the Cochrane Library, and Web of Science, were searched with the given search terms but without language restriction. The studies that met the inclusion criteria were included. The relevant data were extracted, and two authors independently assessed the quality of the included studies. We performed the present study using the STATA software package.
The present work included seven studies with 434 patients with chronic low back pain (CLBP). The risk of bias in the included randomized controlled trials (RCTs) was rated from low to unclear, and all the included observational studies were rated as high quality. The result of the meta-analysis revealed that there were significant differences in pain intensity standardized mean difference (SMD): 3.09, 95% confidence interval (CI): 1.60-4.58; p<0.01 and self-assessed improvement/satisfaction odds ratio (OR): 11.41, 95% CI: 3.39-38.41; p=0.05 after ISI compared to before treatment. However, no significant differences in the proportion of patients with full or part-time employment (OR: 1.03, 95% CI: 0.55-1.91; p>0.05), receiving additional care for CLBP (OR: 0.78, 95% CI: 0.36-1.71; p>0.05), and serious adverse events (OR: 1.09, 95% CI: 0.58 to 2.05; p>0.05) were detected between the groups.
Among CLBP patients with MCI, the use of ISI was significantly associated with a reduction in pain intensity in the short term.
The key physics of the spin valve involves spin-polarized conduction electrons propagating between two magnetic layers such that the device conductance is controlled by the relative magnetization ...orientation of two magnetic layers. Here, we report the effect of a magnon valve which is made of two ferromagnetic insulators (YIG) separated by a nonmagnetic spacer layer (Au). When a thermal gradient is applied perpendicular to the layers, the inverse spin Hall voltage output detected by a Pt bar placed on top of the magnon valve depends on the relative orientation of the magnetization of two YIG layers, indicating the magnon current induced by the spin Seebeck effect at one layer affects the magnon current in the other layer separated by Au. We interpret the magnon valve effect by the angular momentum conversion and propagation between magnons in two YIG layers and conduction electrons in the Au layer. The temperature dependence of the magnon valve ratio shows approximately a power law, supporting the above magnon-electron spin conversion mechanism. This work opens a new class of valve structures beyond the conventional spin valves.
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