Characteristics of patients with SARS-COV-2 PCR re-positivity after recovering from COVID-19.

The purpose of this study was to analyse the clinical characteristics of patients with severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) PCR re-positivity after recovering from coronavirus disease 2019 (COVID-19). Patients (n = 1391) from Guangzhou, China, who had recovered from COVID-19 were recruited between 7 September 2021 and 11 March 2022. Data on epidemiology, symptoms, laboratory test results and treatment were analysed. In this study, 42.7% of recovered patients had re-positive result. Most re-positive patients were asymptomatic, did not have severe comorbidities, and were not contagious. The re-positivity rate was 39%, 46%, 11% and 25% in patients who had received inactivated, mRNA, adenovirus vector and recombinant subunit vaccines, respectively. Seven independent risk factors for testing re-positive were identified, and a predictive model was constructed using these variables. The predictors of re-positivity were COVID-19 vaccination status, previous SARs-CoV-12 infection prior to the most recent episode, renal function, SARS-CoV-2 IgG and IgM antibody levels and white blood cell count. The predictive model could benefit the control of the spread of COVID-19.

Important Role of NO3 Radical to Nitrate Formation Aloft in Urban Beijing: Insights from Triple Oxygen Isotopes Measured at the Tower.

Until now, there has been a lack of knowledge regarding the vertical profiles of nitrate formation in the urban boundary layer (BL) based on triple oxygen isotopes. Here, we conducted vertical measurements of the oxygen anomaly of nitrate (Δ17O-NO3-) on a 325 m meteorological tower in urban Beijing during the winter and summer. The simultaneous vertical measurements suggested different formation mechanisms of nitrate aerosols at ground level and 120 and 260 m in the winter due to the less efficient vertical mixing under stable atmospheric conditions. Particularly, different chemical processes of nitrate aerosols at the three heights were found between clean days and polluted days in the winter. On clean days, nocturnal chemistry (NO3 + HC and N2O5 uptake) contributed to nitrate production equally with OH/H2O + NO2 at ground level, while it dominated aloft (contributing 80% of nitrate production at 260 m), due to the higher aerosol liquid water content and O3 concentration there. On polluted days, nocturnal reactions dominated the formation of nitrate at the three heights. Particularly, the contribution of the OH/H2O + NO2 pathway to nitrate production increased from the ground level to 120 m might be attributed to the hydrolysis of NO2 to HONO and then further photolysis to OH radicals in the day. In contrast, the proportion of N2O5 + H2O decreased at 260 m, likely due to the low relative humidity aloft that inhibited the N2O5 hydrolysis reactions in the residual layer. Our results highlighted that the differences between meteorology and gaseous precursors could largely affect particulate nitrate formation at different heights within the polluted urban BL.

Influence of Isomerism on Radioluminescence of Purely Organic Phosphorescence Scintillators.

There are few reports about purely organic phosphorescence scintillators, and the relationship between molecular structures and radioluminescence in organic scintillators is still unclear. Here, we presented isomerism strategy to study the effect of molecular structures on radioluminescence. The isomers can achieve phosphorescence efficiency of up to 22.8 % by ultraviolet irradiation. Under X-ray irradiation, both m-BA and p-BA show excellent radioluminescence, while o-BA has almost no radioluminescence. Through experimental and theoretical investigation, we found that radioluminescence was not only affected by non-radiation in emissive process, but also highly depended on the material conductivity caused by the different molecular packing. This study not only allows us to clearly understand the relationship between the molecular structures and radioluminescence, but also provides a guidance to rationally design new organic scintillators.

The semicircular canal function tests contribute to identifying unilateral idiopathic sudden sensorineural hearing loss with vertigo.

BACKGROUND: Few studies focused on the prognosis of unilateral idiopathic sudden sensorineural hearing loss (UISSNHL) with vertigo. OBJECTIVES: To describe how the semicircular canal (SCC) function tests may prove helpful in the diagnosis of UISSNHL with vertigo. MATERIAL AND METHODS: 59 UISSNHL patients underwent audiometry, caloric test and video head impulse test (vHIT). The correlation between hearing loss and SCC dysfunction was analyzed. RESULTS: The results showed significant differences of hearing loss grades (p = 0.004) and hearing loss configurations (p = 0.009) between UISSNHL patients with and without vertigo. In vHIT, the gains of horizontal canal (HC) and posterior canal (PC) were more frequently impaired compared with that of anterior canal (AC). The abnormal rate of caloric test was the highest, followed by the abnormal rates of HC and PC gain. A significant difference of abnormal rate of HC gain was only found between the mild and moderate UISSNHL patients with and without vertigo (p = 0.029). CONCLUSION: Abnormal SCC function happens frequently in patients with profound hearing loss. Ipsilesional abnormal vHIT (especially the HC gain) in the presence of abnormal caloric test is a pattern of findings observed in mild and moderate UISSNHL patients with vertigo.

Pseudomonas mangrovi sp. nov., isolated from mangrove soil.

A Gram-stain-negative, aerobic, non-motile, short-rod-shaped bacterium, designated as strain TC11T, was isolated from rhizosphere soil of mangrove forest (Kandeliaobovata) in Fugong village, Zhangzhou, Fujian, China. Strain TC11T grew at 15-45 °C (optimum, 35 °C), 0-8 % (w/v) NaCl (optimum, 1 %, w/v) and pH 5.5-9.5 (optimum, pH 7.5). Phylogenetic analyses revealed that strain TC11T belonged to a clade of the genus Pseudomonas and showed the highest sequence similarity of 98.4 % to Pseudomonas fluvialis ASS-1T, followed by Pseudomonas oleovorans subsp.oleovorans DSM 1045T (97.9 %), Pseudomonas indoloxydans JCM 14246T (97.7 %), Pseudomonas guguanensis JCM 18416T(97.6 %) and Pseudomonas alcaliphila JCM 10630T (97.5 %) on the basis of their 16S rRNA gene sequences. The DNA G+C content was 64.3 mol%. In silico DNA-DNA hybridization and average nucleotide identity values between strain TC11T and the reference strains were 19-22 % and 72-78 %, respectively. Studies based on the three housekeeping genes, rpoB, gyrB and rpoD, further confirmed that strain TC11T is a novel member of the genus Pseudomonas. The major fatty acids of strain TC11Twere C16 : 0, summed feature 8 (C18 : 1ω6c/C18 : 1ω7c) and summed feature 3 (C16 : 1ω7c/C16 : 1ω6c). The sole isoprenoid quinone was Q-9. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Based on the phenotypic, chemotaxonomic and phylogenetic properties, strain TC11T represents a novel species of the genus Pseudomonas, for which the name Pseudomonasmangrovi sp. nov., is proposed. The type strain is TC11T (=KCTC 62159=MCCC 1K03499).

Pneumonia caused by extensive drug-resistant Acinetobacter baumannii among hospitalized patients: genetic relationships, risk factors and mortality.

BACKGROUND: The clonal spread of multiple drug-resistant Acinetobacter baumannii is an emerging problem in China. We analysed the molecular epidemiology of Acinetobacter baumanni isolates at three teaching hospitals and investigated the risk factors, clinical features, and outcomes of hospital-acquired pneumonia caused by extensive drug-resistant Acinetobacter baumannii (XDRAB) infection in Guangzhou, China. METHODS: Fifty-two A. baumannii isolates were collected. Multilocus sequence typing (MLST) was used to assess the genetic relationships among the isolates. The bla OXA-51-like gene was amplified using polymerase chain reaction (PCR) and sequencing. The resistance phenotypes were determined using the disc diffusion method. A retrospective case-control study was performed to determine factors associated with XDRAB pneumonia. RESULTS: Most of the 52 A. baumannii isolates (N = 37, 71.2%) were collected from intensive care units (ICUs). The respiratory system was the most common bodily site from which A. baumannii was recovered (N = 45, 86.5%). Disc diffusion classified the isolates into 17 multidrug-resistant (MDR) and 35 extensively drug-resistant (XDR) strains. MLST grouped the A. baumannii isolates into 5 existing sequence types (STs) and 7 new STs. ST195 and ST208 accounted for 69.2% (36/52) of the isolates. The clonal relationship analysis showed that ST195 and ST208 belonged to clonal complex (CC) 92. According to the sequence-based typing (SBT) of the bla OXA-51-like gene, 51 A. baumannii isolates carried OXA-66 and the rest carried OXA-199. There were no significant differences with respect to the resistance phenotype between the CC92 and non-CC92 strains (P = 0.767). The multivariate analysis showed that the APACHE II score, chronic obstructive pulmonary disease (COPD) and cardiac disease were independent risk factors for XDRAB pneumonia (P < 0.05). The mortality rate of XDRAB pneumonia was high (up to 42.8%), but pneumonia caused by XDRAB was not associated with in-hospital mortality (P = 0.582). CONCLUSIONS: ST195 may be the most common ST in Guangzhou, China, and may serve as a severe epidemic marker. SBT of bla OXA-51-like gene variants may not result in sufficient dissimilarities to type isolates in a small-scale, geographically restricted study of a single region. XDRAB pneumonia was strongly related to systemic illnesses and the APACHE II score but was not associated with in-hospital mortality.

Spot centroid sensitivity to angle of intensity on image detector with lenslet array.

Lenslet array was introduced to an image detector to compensate for low sensitivity. These lenses deviate the light from different incident angles and potentially introduce errors when subpixel accuracy is needed. We investigated the spot centroid position because the angle of incidence changes on a Kodak KAI-16000 image detector with lenslet array. In our experiment, we noticed that there is a cubic dependency on the incident angle. The experimental results show that dependence on the angle of incidence is related to the lenslet array in the Kodak detector used for the pentaprism test. This situation caused an error in spherical aberration on the test surface after integration. The magnitude of the cubic component at incident angle of 14° (equivalent to F/2) is 11.6 µm, which corresponds to a 48 nm rms spherical aberration for the test surface and brings the scanning pentaprism test closer to the principal test while there is a 56 nm rms discrepancy. The discrepancy in spherical aberration between the two tests reduced to 8 nm after this calibration. It also showed the contrast measurement results for the Kodak detector and PointGrey detector. We performed experiments with two different detectors to quantify this effect.

[Correlation Study on Pathological Characteristics of Target Organs and Excess Evil Syndrome in IgA Nephropathy].

OBJECTIVE: To explore the correlation between pathological characteristics of target organs and excess evil syndrome in IgA nephropathy. METHODS: Data were collected in multicenter cooperation. Totally 266 IgA nephropathy patients were typed into exogenous wind-heat affection syndrome (49 cases), lower energizer damp-heat syndrome (100 cases), damp-phlegm syndrome (43 cases), and blood stasis syndrome (74 cases). Meanwhile, percutaneous renal biopsy was performed in all patients for Hass classification, Oxford classification, Katafuchi integral, and Jiang's classification methods. The correlation between excess evil syndrome and pathological index was analyzed. RESULTS: Four syndrome types were correlated with their Hass levels (r = 0. 341, P <0. 01). Affection of exogenous wind-heat syndrome was correlated with segmental proliferation of endothelial cells and damaged active lesions of segmental capillary loops. Lower-energizer damp-heat syndrome was associated with Hass III level, destroying active lesions of capillary loops, segmental proliferation of endothelial cells, glomerular segmental lesions, focal interstitial infiltration of inflammatory cells, focal interstitial fibrosis and tubular atrophy. Blood stasis syndrome was associated with Hass IV level, glomerular sclerosis, segmental glomerulosclerosis (S)/adhesion, mesangial hypercellularity (M), angiohyalinosis, multi-foci interstitial infiltration of inflammatory cells, multi-foci interstitial fibrosis and tubular atrophy. Phlegm-damp syndrome had higher proportions of Hass I and III levels, but with no association with other pathological parameters. CONCLUSIONS: Excess evil syndrome was associated with partial pathological characteristics of IgA nephropathy. It could reflect pathological damage degree of target organs, activities, chronic lesions, and prognosis of IgA nephropathy to certain extent. Correlated pathological characteristics and its evolution could indicate excess evil syndrome types and their evolution rules.

Lidocaine potentiates the deleterious effects of triamcinolone acetonide on tenocytes.

BACKGROUND: Local anesthetics are commonly used for the treatment of a variety of tendinopathies in combination with corticosteroids injection. The goal of this study was to evaluate the effects of lidocaine and triamcinolone acetonide (TA) on cultured rat tenocytes and to determine whether there is a synergistic effect. MATERIAL/METHODS: Rat patellar tendon-derived tenocytes were cultured with or without TA and lidocaine, and the culture without any additive served as the control. Cell morphology and cell viability were evaluated. Expressions of tenocyte-related genes were measured by qRT-PCR. RESULTS: TA, when exposed to tenocytes in vitro, significantly decreased cell viability. The cells cultured with TA had a flattened shape. Moreover, the expressions of tenocyte-related genes in tenocytes were markedly decreased in the TA-treated group. We found that 1% lidocaine synergistically increased the deleterious effects of TA. CONCLUSIONS: Our data provide evidence of the detrimental effects of these drugs on tendon tissues. Injection of TA in combination with 1% lidocaine should be used with caution.

The impact of oxygen content on Staphylococcus epidermidis pathogenesis in ocular infection based on clinical characteristics, transcriptome and metabolome analysis.

Introduction: This study aims to delineate the etiology and prevalence of isolated pathogens, along with the clinical characteristics of endophthalmitis patients over a 9-year period at hospital in Southwest of China. Additionally, we investigating the metabolic and cellular processes related to environmental factors may offer novel insights into endophthalmitis. Methods: We analyzed data pertaining to endophthalmitis patients treated at the Affiliated Hospital of Yunnan University from 2015 to 2023. According to our clinical data, we conducted an experiment based on transcriptomics and metabolomics analysis to verify whether environmental factors affect behavior of S. epidermidis by culturating S. epidermidis under oxic and microoxic condition. Results: In this study, 2,712 fungi or bacteria strains have been analyzed, gram-positive bacteria constituted 65.08%, with S. epidermidis being the most predominant species (25.55%). Ophthalmic trauma was the primary pathogenic factor for S. epidermidis ocular infections. Regarding fluoroquinolones, S. epidermidis exhibited the higher resistance rate to levofloxacin than moxifloxacin. Moreover, our investigation revealed that S. epidermidis in microoxic environment increase in energy metabolism, amino acid metabolism, and membrane transport. Conclusion: Our findings underscore the significance of S. epidermidis as a crucial pathogen responsible for infectious endophthalmitis. It is crucial to exercise vigilance when considering Levofloxacin as the first-line drug for empiric endophthalmitis treatment. The metabolites alteration observed during the commensal-to-pathogen conversion under microoxic condition serve as a pivotal environmental signal contributing to S. epidermidis metabolism remodeling, toward more pathogenic state.

Discovery of a small molecular compound simultaneously targeting RXR and HADC: design, synthesis, molecular docking and bioassay.

Retinoid X receptor (RXR) and Histone deacetylase (HDAC) are considered important targets for anti-cancer therapy due to their crucial roles in genetic or epigenetic regulations of cancer development and progression. Here, we have designed and synthesized a novel compound which targets both RXR and HADC. This dual-targeting agent is derived from bexarotene and suberoylanilide hydroxamic acid (SAHA), prototypical RXR agonist and HDAC inhibitor, respectively. Molecular docking studies demonstrate that this agent has a relatively strong affinity to RXR and HADC. Importantly, it presents the potentials of activation of RXR and inhibition of HDAC in both cell-free and whole-cell assays, and displays anti-proliferative effect on representative cancer cell lines and drug-resistant cancer cell lines.

Effects of a combination of amlodipine and imipenem on 42 clinical isolates of Acinetobacter baumannii obtained from a teaching hospital in Guangzhou, China.

BACKGROUND: The clonal spread of Acinetobacter baumannii is a global problem, and carbapenems, such as imipenem, remain the first-choice agent against A. baumannii. Using synergy to enhance the antibiotic activity of carbapenems could be useful. Here, amlodipine (AML) was tested alone and with imipenem against A. baumannii isolates. METHODS: Forty-two isolates of A. baumannii were collected. Multilocus sequence typing (MLST) assessed the genetic relationship of the isolates. The resistance phenotypes were determined using disc diffusion. The minimum inhibitory concentrations (MICs) of the drugs were determined by broth microdilution. The combined effects of the drugs were determined by a checkerboard procedure. Metallo-ß-lactamase (MBL) was determined using the MBL Etest. RESULTS: Forty-two A. baumannii isolates were collected from 42 patients who were mostly older than 65 years and had long inpatient stays (≥ 7 days). A. baumannii was mostly recovered from the respiratory system (N = 35, 83.3%). Most patients (N = 27, 64.3%) received care in intensive care units (ICUs). Disc diffusion testing demonstrated that A. baumannii susceptibility to polymyxin B was 100%, while susceptibility to other antimicrobial agents was less than 30%, classifying the isolates into 10 MDR and 32 XDR strains. MLST grouped the A. baumannii isolates into 4 existing STs and 6 new STs. STn4 carried allele G1, with a T → C mutation at nt3 on the gpi111 locus. STn5 carried allele A1, possessing A → C mutations at nt156 and nt159 on the gltA1 locus. ST195 and ST208 accounted for 68.05% (29/42) of the isolates. Clonal relation analysis showed that ST195 and ST208 belonged to clonal complex (CC) 92. The inhibitory concentration of imipenem ranged from 0.5 to 32 µg/ml, and that of AML ranged from 40 to 320 µg/ml. In combination, the susceptibility rate of A. baumannii isolates increased from 16.7% to 54.8% (P = 0.001). In the checkerboard procedure, half of the isolates (N = 21, 50.0%) demonstrated synergy or partial synergy with the drug combination. The MBL Etest revealed that 1 A. baumannii strain (N = 1, 2.4%) produced MBL. CONCLUSIONS: CC92 was the major clone spreading in our hospital. AML improved the activity of imipenem against A. baumannii isolates in vitro but did not inhibit MBL.

GRIK3 deficiency promotes non-small cell lung cancer progression by the regulation of the UBE2C/CDK1/Wnt signaling pathway.

Glutamate ionotropic receptor kainate type subunit 3 (GRIK3) is a predominant excitatory neurotransmitter receptor in the mammalian brain. While it is known that GRIK3 is involved in normal neurophysiologic processes, its biological functions in tumor progression are still poorly understood due to limited investigation. In this study, we reported for the first time that GRIK3 expression was downregulated in non-small cell lung cancer (NSCLC) tissues as compared to paracarcinoma tissues. Additionally, we observed that GRIK3 expression was strongly correlated with the prognosis of NSCLC patients. We also noted that GRIK3 suppressed the cell proliferation and migration capability of NSCLC cells, thereby inhibiting xenografts growth and metastasis. Mechanistically, GRIK3 deficiency increased the expression of ubiquitin-conjugating enzyme E2 C (UBE2C) and cyclin-dependent kinase 1 (CDK1), which resulted in the activation of the Wnt signaling pathway and enhanced NSCLC progression. Our findings suggest that GRIK3 plays a role in regulating NSCLC progression and that its expression may serve as an independent prognostic indicator for NSCLC patients.

Enhancing viability of Lactobacillus plantarum encapsulated by alginate-gelatin hydrogel beads during gastrointestinal digestion, storage and in the mimic beverage systems.

To improve the viability of Lactobacillus plantarum (P) during digestion and storage, the probiotics were encapsulated by alginate (ALG) and alginate-gelatin (ALG-GE) hydrogels beads. ALG-P-GE showed much better physicochemical properties than ALG-P. The scanning electron microscopy (SEM) results validated the incorporation of bacterial cells into the beads. ALG-P-GE exhibited good encapsulation efficiency of 97.7 %, and the storage and thermal stability of probiotic were increased by 15 % and 8 %, respectively, when comparing with ALG-P. ALG-P-GE beads could protect the probiotics from inactivation in simulated gastric fluid and then release it in simulated intestinal fluid. The protective mechanism of ALG-GE for probiotics was further studied by fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and found that ALG and GE can form gel network through hydrogen bonding and electrostatic interactions. In the mimic beverage systems, ALG-P-GE beads could protect the encapsulated probiotics and increase its viability. The storage, thermal, and digestion stability of encapsulated probiotic were significantly increased and showed high viability in the mimic beverage systems. ALG-P-GE beads have great potential for the protection and delivery of probiotics in food systems.

[Characteristics of Soil Erosion and Nitrogen Loss in Vegetable Field Under Natural Rainfall].

The effects of vegetable planting on soil loss and nutrient loss, runoff, soil erosion, and nitrogen (ammonium nitrogen and nitrate nitrogen) losses under individual rainfalls of fruit- and leaf-vegetable fields between April to October in 2021 were observed using in-situ observation testing. The results showed that: ① the runoff, erosion, and nitrogen loss of the fruit-vegetable pattern (eggplant-chili) were 1.27-2.00 times those under the leaf-vegetable pattern (leaf lettuce-sweet potato leaves), especially under the second season vegetable period. Those losses under the second season vegetable accounted for 50.86%-68.83% of the total losses under different vegetable patterns, which were approximately 1.03-2.04 times those under the first season vegetable. The runoff, erosion, and nutrient loss of vegetable fields under different treatments were both concentrated in June and July, and the nitrogen loss was mainly in the form of nitrate nitrogen with surface runoff. ② The runoff, erosion, and nutrient losses under individual rainfalls of vegetable fields under different treatments fluctuated among the vegetable growing season, and the losses were mainly concentrated in several typical rainfall events. On the whole, the loss and concentration of nitrate and ammonium nitrogen in runoff and erosion sediment of vegetables in the first season were lower than those in the second season. The runoff, erosion, and loss of ammonium nitrogen and nitrate nitrogen of fruit-vegetable were higher than those of leaf-vegetable. ③ Both rainfall amount and maximum 30 min rainfall intensity had significantly positive effects on runoff, soil loss, and nitrogen loss. Runoff, erosion, and nutrient losses under different vegetable patterns were mainly generated by moderate rain, heavy rain, and heavy rainstorms, which accounted for 29.58%-46.68%, 24.54%-36.79%, and 24.01%-39.13% of the total losses, respectively. The results also showed that soil erosion and nutrient losses generated by different rainfall grades were obviously different for the fruit- and leaf-vegetable treatments. The results indicated that the vegetable pattern had significant impacts on soil loss and nutrient loss, and the leaf-vegetable pattern could reduce soil erosion and nutrient loss compared with the fruit-vegetable pattern. Furthermore, for different vegetable patterns and vegetable growing seasons, the effects of rainfall on soil loss and nutrient loss were quite different. The results of this study were helpful in clarifying the soil erosion and nutrient loss characteristics of vegetable fields in South China.

Comparison of Azvudine and Nirmatrelvir/Ritonavir and Combined Use in Patients with COVID-19.

Purpose: To compare the effectiveness of azvudine and nirmatrelvir/ritonavir for the treatment of coronavirus disease (COVID-19). Patients and Methods: We conducted a retrospective analysis of data from 576 patients with COVID-19, comprising 195 patients without antiviral therapy, 226 patients treated with azvudine, 114 patients treated with nirmatrelvir/ritonavir, and 41 patients were treated with azvudine and nirmatrelvir/ritonavir concurrently. We compared their symptoms, mortality rates, and the length and cost of hospitalization. Results: The incidence of symptoms was similar in patients treated with azvudine and in those treated with nirmatrelvir/ritonavir. However, among patients experiencing weakness, the duration of weakness was significantly shorter in the azvudine group than in the nirmatrelvir/ritonavir group (P=0.029). Mortality did not differ significantly between the azvudine group and the nirmatrelvir/ritonavir group (18.14% vs.10.53%, P=0.068). Among "severe patients", the mortality rate was markedly lower in patients treated with nirmatrelvir/ritonavir than in patients treated with azvudine (16.92% vs.32.17%, P=0.026). In patients with hepatic insufficiency, those treated with nirmatrelvir/ritonavir had substantially lower mortality than those treated with azvudine (15.09% vs.34.25%, P=0.016). In addition, patients treated with nirmatrelvir/ritonavir had longer hospital stays (P=0.002) and higher hospital costs (P<0.001) than those receiving azvudine. Compared with patients treated with nirmatrelvir/ritonavir or azvudine alone, patients taking nirmatrelvir/ritonavir and azvudine concurrently had no significant improvement in survival (P>0.05), length of stay (P>0.05), or hospital costs (P>0.05). Conclusion: Azvudine is recommended for patients with non-severe COVID-19 with weakness. Nirmatrelvir/ritonavir is recommended for patients with severe COVID-19, to reduce mortality, and it could be the best choice for patients with hepatic insufficiency. The concurrent use of nirmatrelvir/ritonavir and azvudine in patients with COVID-19 could be not recommended.

The Application of a Computer Monitoring System Using IoT Technology.

Through the information exchange of the Internet of Things, resources in multiple fields can be integrated to provide users with more comprehensive, diverse, and high-quality services. The computer monitoring system can effectively improve the intelligence and networking of the office and is widely used in many industries. The application of Internet of Things technology can effectively improve the intelligence and networking of computer monitoring systems. The Internet of Things technology can realize the interaction between things and people, help the computer monitoring system to obtain the required information, and truly realize comprehensive monitoring. Based on this, this paper first introduces the basic technology of the Internet of Things technology and analyzes the main points of the computer monitoring technology based on the Internet of Things at this stage and then takes a computer monitoring system as the research object, and further analyzes the computer monitoring system based on the Internet of Things technology to help relevant personnel better apply IoT technology to computer monitoring systems.

The Protective Effect of Sweet Potato Root Tuber on Chemotherapy-Induced Thrombocytopenia.

SCOPE: Sweet potato (Ipomoea batatas L.) is one of the leading crops worldwide, containing high nutritional components such as fiber and polyphenols. Root tuber of Simon 1 (SIMON), a cultivar of sweet potato, is a folk food in China with a hemostasis function but lacking experimental data support. METHODS AND RESULTS: Now the protective effect of SIMON on chemotherapy-induced thrombocytopenia (CIT), a serious complication of cancer treatment, is investigated for the first time by a CIT mouse model induced by intraperitoneal injection of carboplatin. As a result, SIMON raises the number of peripheral platelets, white blood cells, and bone marrow nucleated cells in CIT mice significantly. Besides, carboplatin-induced atrophy of the thymus, spleen, and disordered metabolism of the inflammatory immune system and glycerophospholipids are also reversed by SIMON. Phytochemical analysis of SIMON indicates 16 compounds including eight phenolic derivatives, which might be associated with its anti-CIT bioactivity. CONCLUSION: Sweet potato (SIMON) may be an efficient function food in the prevention of bleeding disorders.

[Changes in Carbonaceous Aerosol in the Northern Suburbs of Nanjing from 2015 to 2019].

Carbonaceous aerosol is an important component of atmospheric fine particles that has an important impact on air quality, human health, and climate change. In order to explore the long-term changes in carbonaceous aerosol under the background of emission reduction, this study measured the mass concentrations of organic carbon (OC) and elemental carbon (EC) of PM2.5, which collected in the northern suburbs of Nanjing for five years (December 17, 2014 to January 5, 2020). The results showed that the five-year average ρ(OC) and ρ(EC) were (10.2±5.3) µg·m-3 and (1.6±1.1) µg·m-3, accounting for 31.1% and 5.2% of PM2.5, respectively. OC and EC concentrations were both high in winter and low in summer. According to the nonparametric Mann-Kendall test and Sen's slope, the mass concentrations of OC and PM2.5 decreased significantly[OC:P<0.0001, -0.79 µg·(m3·a)-1, -0.29%·a-1; PM2.5:P<0.0001, -4.59 µg·(m3·a)-1, -1.58%·a-1]. Although EC had an upward trend, the significance and range of change were not obvious[P=0.02, 0.05 µg·(m3·a)-1, 0.02%·a-1]. OC and EC decreased significantly during winter from 2014 to 2019[OC:P<0.0001, -2.05 µg·(m3·a)-1, -0.74%·a-1; EC:P=0.001, -0.15 µg·(m3·a)-1, -0.05%·a-1], and the decline was more obvious than the whole. The correlation between OC and EC showed that the sources in winter and summer were more complex than those in spring and autumn. According to the characteristic ratio of OC and EC, the contribution of coal combustion and biomass burning decreased from 2015 to 2019, whereas the impact of industrial sources and vehicle emissions became more significant. Corresponding to this was the obvious decline in OC and the slight recovery of EC. The OC/EC ratio was over 2.0, indicating that there was secondary pollution in the study area. Further calculation revealed that the variation in SOC was consistent with that in OC, showing a significant decrease[P<0.0001, -0.47 µg·(m3·a)-1, -0.17%·a-1]. The average mass concentration of SOC was (5.0±3.5) µg·m-3, accounting for 49.2% of OC. These changes indicate clear effects of the prevention and control of air pollution in Nanjing in recent years. Furthermore, future control can focus on the emissions of VOCs to reduce secondary pollution.

Organic phosphorescent scintillation from copolymers by X-ray irradiation.

Scintillators that exhibit X-ray-excited luminescence have great potential in radiation detection, X-ray imaging, radiotherapy, and non-destructive testing. However, most reported scintillators are limited to inorganic or organic crystal materials, which have some obstacles in repeatability and processability. Here we present a facile strategy to achieve the X-ray-excited organic phosphorescent scintillation from amorphous copolymers through the copolymerization of the bromine-substituted chromophores and acrylic acid. These polymeric scintillators exhibit efficient X-ray responsibility and decent phosphorescent quantum yield up to 51.4% under ambient conditions. The universality of the design principle was further confirmed by a series of copolymers with multi-color radioluminescence ranging from green to orange-red. Moreover, we demonstrated their potential application in X-ray radiography. This finding not only outlines a feasible principle to develop X-ray responsive phosphorescent polymers, but also expands the potential applications of polymer materials with phosphorescence features.