多维视域与诗意栖息——王少明《岭南乐空中的缪斯》读后

王少明教授的新作《岭南乐空中的缪斯》以多维的视域、多元的角度和立体的构建书写了岭南乐空中群星聚汇的辉煌、展现了岭南三大乐种发展、跌宕的历程和别具一格的魅力,屹立乐坛、独步天下!为学界了解岭南音乐文化和众多名家,把握其外在形态、内在规律、独特风格、超凡意境提供了生动、鲜活的感性体悟与理性思考,让远观岭南音乐文化的同仁、音乐爱好者走进这一自然、美妙的天地,使旁涉这一领域的学者、专家爱上这悠然自在的景致,在万物化醇的韵味中神凝心驻!

Influence of nanoparticle concentrations on flow boiling heat transfer coefficients of Al_2O_3/R141b in micro heat exchanger by direct metal laser sintering

Al2O3/R141b ＋ Span-80 nanorefrigerant for 0.05 wt.% to 0.4 wt.% is prepared by ultrasonic vibration to investigate the influence of nanoparticle concentrations on flow boiling heat transfer of Al2O3/R141b ＋ Span-80 in micro heat exchanger by direct metal laser sintering. Experimental results show that nanoparticle concentrations have significantly impact on heat transfer coefficients by homogeneity test of variances according to mathematical statistics. The heat transfer performance of Al2O3/R141b ＋ Span-80 nanorefrigerant is enhanced after adding nanoparticles in the pure refrigerant R141b. The heat transfer coefficients of 0.05 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.% and 0.4 wt.% Al2O3/R141 b ＋ Span-80 nanorefrigerant respectively increase by 55.0% 72.0%, 53.0% 42.3% and 39.9% compared with the pure refrigerant R141b. The particle fluxes from viscosity gradient, non-uniform shear rate and Brownian motion cause particles to migrate in fluid especially in the process of flow boiling. This migration motion enhances heat transfer between nanoparticles and fluid. Therefore, the heat transfer performance of nanofluid is enhanced. It is important to note that the heat transfer coefficients nonlinearly increase with nanoparticle concentrations increasing. The heat transfer coefficients reach its maximum value at the mass concentration of 0.1% and then it decreases slightly. There exists an optimal mass concentration corresponding to the best heat transfer enhancement. The reason for the above phenomenon is attributed to nanoparticles deposition on the minichannel wall by Scanning Electron Microscopy observation. The channel surface wettability increases during the flow boiling experiment in the mass concentration range from 0.2 wt.% to 0.4 wt.%. The channel surface with wettability increasing needs more energy to produce a bubble. Therefore, the heat transfer coefficients decrease with nanopartide concentrations in the range from 0.2 wt.% to 0.4 wt.%. In addition, a new correlation has been proposed by fitting the experimental data considering the influence of mass concentrations on the heat trans- fer performance. The new correlation can effectively predict the heat transfer coefficient.

The detection of HBV DNA with gold nanoparticle gene probes

Objective：Gold nanoparticle Hepatitis B virus （HBV） DNA probes were prepared, and their application for HBV DNA measurement was studied. Methods：Alkanethiol modified oligonucleotide was bound with self-made Au nanoparticles to form nanoparticle HBV DNA gene probes, through covalent binding of Au-S. By using a fluorescence-based method, the number of thiol-derivatized, single-stranded oligonucleotides and their hybridization efficiency with complementary oligonucleotides in solution was determined. With the aid of Au nanoparticle-supported mercapto-modified oligonucleotides serving as detection probes, and oligonucleotides immobilized on a nylon membrane surface acting as capturing probes, HBV DNA was detected visually by sandwich hybridization based on highly sensitive aggregation and silver staining. The modified nanoparticle HBV DNA gene probes were also used to detect the HBV DNA extracted from serum in patients with hepatitis B. Results：Compared with bare Au nanoparticles, oligonucleotide modified nanoparticles had a higher stability in NaCl solution or under high temperature environment and the absorbance peak of modified Au nanoparticles shifted from 520nm to 524nm. For Au nanoparticles, the maximal oligonucleotide surface coverage of hexaethiol 30-mer oligonucleotide was （132 ± 10） oligonucleotides per nanoparticle, and the percentage of hybridization strands on nanoparticles was （22 ± 3% ）. Based on a two-probe sandwich hybridization/nanoparticle amplification/silver staining enhancement method, Au nanoparticle gene probes could detect as low as 10^-11 mol/L composite HBV DNA molecules on a nylon membrane and the PCR products of HBV DNA visually. As made evident by transmission electron microscopy, the nanoparticles assembled into large network aggregates when nanoparticle HBV DNA gene probes were applied to detect HBV DNA molecules in liquid. Conclusion：Our results showed that successfully prepared Au nanoparticle HBV DNA gene probes could be used to detect HBV DNA directly. The detection-visuallized method has many advantages, including high sensitivity, simple operation and low cost. This technique has potential applications in many fields, especially in multi-gene detection chips.

Thermo-Mechanical Treatment on Microstructure and Mechanical Properties of Mg-5.0Sn-1.0Mn-0.4Zr Alloy

The mechanical properties and microstructure of an as-cast Mg-5.0Sn-1.0Mn-0.4Zr alloy were investigated during thermo mechanical treatments consisting of hot extrusion, rolling, and ageing at 200°C. The results indicate that only Mg2Sn phases formed in the Mg matrix, Mn and Zr do not cause the formation of any new phases. The average grain size, tensile strength and elongation were 22 μm, 285 MPa, and 14.5%, respectively, after extrusion + rolling + ageing treatment (ERA). The mechanical properties of ERA alloys with a peak hardness of 81 HV and 6.7% are improved compared with those of EA (extrusion + ageing treatment) samples;these changes are attributed to grain refinement and solid solution strengthening, age hardening, and precipitation strengthening.

A Comparative Study on the Selected Area Electron Diffraction Pattern of Fe Oxide/Au Core-shell Structured Nanoparticles

The selected area electron diffraction （SAED） pattern of magnetic iron oxide core/gold shell nanoparticles has been studied. For the composite particles with mean size less than 10 nm, their SAED pattern is found to be different from either the pattern of pure Fe oxide nanoparticles or that of pure Au particles. Based on the fact that the ring diameters of these composite particles fit the characteristic relation for the fcc structure, the Au atoms on surfaces of the concerned particles are supposed to pack in a way more tightly than they usually do in pure Au nanoparticles. The driving force for this is the coherency strain which enables the shell material at the heterostructured interface to adapt the lattice parameters of the core.

A New Childhood Pneumonia Diagnosis Method Based on Fine-Grained Convolutional Neural Network

Pneumonia is part of the main diseases causing the death of children.It is generally diagnosed through chest Xray images.With the development of Deep Learning(DL),the diagnosis of pneumonia based on DL has received extensive attention.However,due to the small difference between pneumonia and normal images,the performance of DL methods could be improved.This research proposes a new fine-grained Convolutional Neural Network(CNN)for children’s pneumonia diagnosis(FG-CPD).Firstly,the fine-grainedCNNclassificationwhich can handle the slight difference in images is investigated.To obtain the raw images from the real-world chest X-ray data,the YOLOv4 algorithm is trained to detect and position the chest part in the raw images.Secondly,a novel attention network is proposed,named SGNet,which integrates the spatial information and channel information of the images to locate the discriminative parts in the chest image for expanding the difference between pneumonia and normal images.Thirdly,the automatic data augmentation method is adopted to increase the diversity of the images and avoid the overfitting of FG-CPD.The FG-CPD has been tested on the public Chest X-ray 2017 dataset,and the results show that it has achieved great effect.Then,the FG-CPD is tested on the real chest X-ray images from children aged 3–12 years ago from Tongji Hospital.The results show that FG-CPD has achieved up to 96.91%accuracy,which can validate the potential of the FG-CPD.

Characteristics of Fluid Inclusions and Determination of Hydrocarbon Accumulation Period of Caofeidian 18-1/2Buried Hill Reservoirs in Bozhong Depression,Bohai Bay Basin

The study area Caofeidian 18-1/2 structure is located in the Shadongnan structural belt at the southeast subduction end of the Shaleitian salient in the western Bohai Sea. The characteristics of reservoirs and fluid inclusions from 13 core samples near the buried hills in the study area are studied,and regional geology and conditions for reservoir formation are analyzed to reveal the characteristics and the processes of reservoir formation. Phase I oil and gas inclusions are mainly developed,and the abundance of oil and gas inclusions in this period is high( GOI is about 15%). The homogenization temperature of the hydrocarbon-containing brine inclusions accompanying them is mainly 90-120 ℃ . The simulation results of burial history and thermal history show that the main charging period of oil and gas is the present Himalayan tectonic movement period since 8 Ma,and mainly through unconformities,faults,and drainage systems,they are migrated and accumulated into fault anticline traps of Dongying Formation mudstone( E_d).

Microstructure and Mechanical Properties of Medical Magnesium Alloy Fabricated by Unequal Channel Angular Pressing

A new unequal channel angular pressing (UCAP) procedure is proposed for ultrafine-grained metals and alloys. The microstructures and mechanical properties of Mg-5.8Zn-1.2Y-0.7Zr alloys subjected to unequal channel angular pressing (UCAP) are investigated. It is found that the optimum condition in UCAPed alloy is obtained at 523 K with a largest elongation to failure of 13.1% and ultimate tensile strength of ~400 MPa. Microstructural observations show that the grain size is refined to ~1.0 μm during UCAP. The probable mechanisms for these high mechanical properties are attributed to grain size and destroyed secondary phase strengthening effects and fine precipitates formed during pressing at high temperature by severe shear and plastic deformation.

A great pediatrician and scholar devoting his whole life to pediatric infectious and digestive diseases—In memoriam of Professor Yongsui Dong

Professor Yongsui Dong(April 1932–January 2023)was a chief physician and doctoral supervisor of the Department of Pediatrics,Tongji Hospital,Tongji Medical College of Huazhong University of Science and Technology,and a pioneer,medical educator,and clinical scientist in the field of pediatric infectious and digestive diseases in China.Professor Dong graduated from the Medical College of Fudan University(formerly Shanghai First Medical College)with excellent grades in 1956.

Prevalence of vitamin D deficiency in girls with idiopathic central precocious puberty

The relationship between vitamin D deficiency and idiopathic central precocious puberty （ICPP） has been recently documented. In this study, 280 girls diagnosed with ICPP and 188 normal puberty control girls of similar ages were enrolled and retrospectively studied. The ICPP group had significantly lower serum 25- hydroxyvitamin D （25[OH]D） levels than the control group. Furthermore, a nonlinear relationship was found between serum 25[OH]D and ICPP, and a cut-offpoint for serum 25[OH]D was found at 31.8 ng/ml for ICPP with and without adjusting the different confounding factors. Girls with serum 25[OH]D 〉~ 31.8 ng/ml had a lower odds ratio （unadjusted： OR 0.36, 95% CI 0.15 to 0.83, P 〈 0.05; height and weight adjusted： OR 0.44, 95~0 CI 0.18 to 1.08, P = 0.072; BMI adjusted： OR 0.36, 95% CI 0.16 to 0.84, P 〈 0.05）. The ICPP subjects with 25[OH]D deficiency had a higher body mass index （BMI） than the subjects from the two other subgroups. Correlation analysis showed that vitamin D level is correlated with BMI and some metabolic parameters in the ICPP group. Our study suggested that vitamin D status may be associated with ICPP risk and may have a threshold effect on ICPP.

The mechanism underlying extrapulmonary complications of the coronavirus disease 2019 and its therapeutic implication

The coronavirus disease 2019(COVID-19)is a highly transmissible disease caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)that poses a major threat to global public health.Although COVID-19 primarily affects the respiratory system,causing severe pneumonia and acute respiratory distress syndrome in severe cases,it can also result in multiple extrapulmonary complications.

Relationship between Tanlu Fault and Hydrocarbon Accumulation in Liaozhong Sag, Bohai Bay, Eastern China

Tanlu fault （Liaozhong segment） goes straight through Liaodong Bay along NNE direc- tion and it is divided into three segments, i.e., the northern segment, the middle segment and the south- ern segment, according to the differences in structural features. There are obvious changes in deposit thickness, sag structure, tectonic nature and other aspects of the layers. Tanlu fault is a special control- ling factor concerning the reservoir formation in Liaozhong sag. First, its activities affect paleogeo- morphology and paleogeographic framework and control the distribution of the sedimentary facies and then they proceed to control the distribution of the source rock and reservoir sand bodies. Second, its activities affect the formation and deformation of the structure, control the formation of abundant traps and cause the destruction of some traps. Third, its activities also affect the juxtaposition relation among the fault, the sand bodies and unconformity surfaces and control the function and efficacy of the three as the main hydrocarbon translocation system. In this paper the hydrocarbon reservoir formation process of JZ21-1, JXI-1 and LD27~2 oil and gas fields, the representatives of Tanlu strike slip fault zone are mainly analyzed. The modes of hydrocarbon reservoir formation can be generalized as follows--hydrocarbon source acts as ＂soil＂ and oil and gas as ＂nutrient＂; hydrocarbon expulsion relies on ＂roots＂; hydrocarbon migration relies on ＂trunks＂; reservoir forms in ＂brunches＂ and the whole process follows the pattern that ＂hydrocarbon accumulates in strike slips and oil and gas reservoir forms like the growth of trees＂.

Clinical evaluation of recombinant human growth hormone injection in children with growth hormone deficiency

Recombinant human growth hormone(rhGH)has been widely used in the clinical treatment of growth hormone deficiency.To simplify the injection process and increase drug compliance,application of the GH injection has become a new treatment plan in recent years.The purpose of the current study was to evaluate the efficacy and safety of rhGH injection for the treatment of growth hormone deficiency(GHD)in children in China.In a nationwide,noncomparative,prospective,randomized,open trial,31 children with confirmed complete GHD received subcutaneous injection of rhGH at 0.25 mg/kg$wk(0.107 IU/kg$d).The injection was given daily and the total weekly amount was separated into 6–7 injections.The patients were followed up at 3-month intervals and the treatment duration was 12 months.The height(HT),annual growth velocity(GV),mean height standard deviation score(HT SDS),blood serum insulin-like growth factor I(IGF-I),insulin-like growth factor binding protein 3(IGFBP-3),and bone maturity before and after treatment were compared,and the safety of the treatment was analyzed.The mean HT,GV,and HT SDS were increased from 109.0�14 cm,2.7�0.9 cm/yr,and–4.62�1.46 at baseline to 121.8�13.4 cm,12.9�3.3 cm/yr,and–2.47�1.86 after 12 months of treatment,respectively(P<0.001).At the same time,blood IGF-I and IGFBP-3 were increased significantly[41.27�64.43μg/L vs 159.21�167.92μg/L and 1540.00�1325.11 mg/L vs 3533.93�1413.82 mg/L,respectively(P<0.001)].The bone age assessments performed 6 and 12 months after the treatment showed that no advanced bone maturation was noted.No serious adverse events occurred during the treatment,and the drug-related adverse events were mainly decreased thyroid function.We conclude that rhGH injection is a safe and effective drug for treatment of growth hormone deficiency in children.

Effect of long-acting polyethylene glycol recombinant human growth hormone dosages in pediatric practice:A pooled analysis of two phase IV randomized controlled trials

To the Editor:Growth hormone deficiency(GHD)impairs growth and development,affecting approximately 1 in 4000 children worldwide.[1]Recombinant human growth hormone(rhGH)has been standard practice since 1985.[2]However,compliance has been challenged by the need for frequent injections.Polyethylene glycol rhGH(PEG-rhGH)was developed,improving protein stability and extending half-life.Some studies suggested that a weekly dosage of 0.20 mg/kg of PEG-rhGH offers improved growth rates and increased insulin-like growth factor-1 standard deviation score(IGF-1 SDS)without novel toxicities.[3]Here,we present a pooled analysis of two phase IV trials evaluating the efficacy and safety of various PEG-rhGH dosages in GHD.