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The school–vacation cycle may have impacts on the psychological states of adolescents. However, little evidence illustrates how transition from school to vacation impacts students’ psychological states (e.g. depression and anxiety).
Aims
To explore the changing patterns of depression and anxiety symptoms among adolescent students within a school–vacation transition and to provide insights for prevention or intervention targets.
Method
Social demographic data and depression and anxiety symptoms were measured from 1380 adolescent students during the school year (age: 13.8 ± 0.88) and 1100 students during the summer vacation (age: 14.2 ± 0.93) in China. Multilevel mixed-effect models were used to examine the changes in depression and anxiety levels and the associated influencing factors. Network analysis was used to explore the symptom network structures of depression and anxiety during school and vacation.
Results
Depression and anxiety symptoms significantly decreased during the vacation compared to the school period. Being female, higher age and with lower mother's educational level were identified as longitudinal risk factors. Interaction effects were found between group (school versus vacation) and the father's educational level as well as grade. Network analyses demonstrated that the anxiety symptoms, including ‘Nervous’, ‘Control worry’ and ‘Relax’ were the most central symptoms at both times. Psychomotor disturbance, including ‘Restless’, ‘Nervous’ and ‘Motor’, bridged depression and anxiety symptoms. The central and bridge symptoms showed variation across the school vacation.
Conclusions
The school–vacation transition had an impact on students’ depression and anxiety symptoms. Prevention and intervention strategies for adolescents’ depression and anxiety during school and vacation periods should be differentially developed.
The formation and evolution of large-scale deposits generated by mass movement are often closely related to tectonic and climatic conditions. Investigating deposits under the influence of complex geological conditions can aid in reconstructing paleoenvironmental characteristics and fluvial geomorphic evolution. The First Bend of the Yangtze River (FBYR), located in the Jinsha River basin in southwest China, represents a significant section characterized by abundant allochthonous deposits. We conducted a detailed investigation of the Hongwen allochthonous deposit (HAD) and the river sediments in the First Bend. Through terrain interpretation, dating, and paleoenvironmental analysis, the HAD was determined to be a complex deposit with multiple sources and stages (46.4–33.5 ka), formed under the combined influence of tectonic activity and climate. Three mass-movement events occurred during the interglacial stage of the last glacial period or its transitional period, coinciding with the rapid uplift stage of the Tibetan Plateau since the late Pleistocene. Prominent features of this period include significant rainfall and tectonic activities. By dating fluvial sediments and examining the evolution of the HAD, we revealed a river incision rate of 2.30 mm/yr for the Jinsha River, providing a basis for analyzing periodic river cutting and the development pattern of surface processes.
We report on an experimental study of turbulent Rayleigh–Bénard convection with asymmetric top and bottom plates. The plates are covered with pyramid-shaped roughness elements whose aspect ratios are $\lambda =1$ or $\lambda =4$. In the low-Rayleigh-number regime ($Ra<1.9\times 10^9$), the heat transport efficiencies in the asymmetric cells, characterized by the Nusselt number, are smaller than those measured in a symmetric $\lambda = 1$ cell and are greater than those for a symmetric $\lambda = 4$ cell, whereas in the high-Rayleigh-number regime ($Ra>1.9\times 10^9$), the Nusselt numbers of the asymmetric cells are, in turn, greater than those for the symmetric cell with $\lambda = 1$ and smaller than those for the symmetric cell with $\lambda = 4$. In addition, the heat transports of individual plates are studied based on the temperature drops across both halves of the cell. In the low-$Ra$ regime, the $\lambda =1$ plate shows higher heat transfer than the $\lambda =4$ plate, while for the high-$Ra$ regime, the $\lambda =4$ plate shows a higher heat transport ability. In both regimes, the individual Nusselt number of the plate with lower heat transfer is insensitive to the topology of the other plate. Besides, it is found that the symmetry of the centre temperature distribution is robust to the symmetry breaking of boundary topographies. For the $Ra$ range explored, a weak temperature inversion is observed in the bulk of asymmetric rough cells. Finally, we remark that the temperature fluctuation at the cell centre and the Reynolds number associated with the large-scale circulation show universal power laws in terms of the flux Rayleigh number as $\sigma _{T_{c}}\sim Ra_F^{0.68}$ and $Re_{LSC}\sim Ra_F^{0.36}$, respectively.
Depression is highly prevalent in haemodialysis patients, and diet might play an important role. Therefore, we conducted this cross-sectional study to determine the association between dietary fatty acids (FA) consumption and the prevalence of depression in maintenance haemodialysis (MHD) patients. Dietary intake was assessed using a validated FFQ between December 2021 and January 2022. The daily intake of dietary FA was categorised into three groups, and the lowest tertile was used as the reference category. Depression was assessed using the Patient Health Questionnaire-9. Logistic regression and restricted cubic spline (RCS) models were applied to assess the relationship between dietary FA intake and the prevalence of depression. As a result, after adjustment for potential confounders, a higher intake of total FA [odds ratio (OR)T3 vs. T1 = 1·59, 95 % confidence interval (CI) = 1·04, 2·46] and saturated fatty acids (SFA) (ORT3 vs. T1 = 1·83, 95 % CI = 1·19, 2·84) was associated with a higher prevalence of depressive symptoms. Significant positive linear trends were also observed (P < 0·05) except for SFA intake. Similarly, the prevalence of depression in MHD patients increased by 20% (OR = 1.20, 95% CI = 1.01–1.43) for each standard deviation increment in SFA intake. RCS analysis indicated an inverse U-shaped correlation between SFA and depression (Pnonlinear > 0·05). Additionally, the sensitivity analysis produced similar results. Furthermore, no statistically significant association was observed in the subgroup analysis with significant interaction. In conclusion, higher total dietary FA and SFA were positively associated with depressive symptoms among MHD patients. These findings inform future research exploring potential mechanism underlying the association between dietary FA and depressive symptoms in MHD patients.
We present a systematic study on the effects of small aspect ratios $\varGamma$ on heat transport in liquid metal convection with a Prandtl number of $Pr=0.029$. The study covers $1/20\le \varGamma \le 1$ experimentally and $1/50\le \varGamma \le 1$ numerically, and a Rayleigh number $Ra$ range of $4\times 10^3 \le Ra \le 7\times 10^{9}$. It is found experimentally that the local effective heat transport scaling exponent $\gamma$ changes with both $Ra$ and $\varGamma$, attaining a $\varGamma$-dependent maximum value before transition-to-turbulence and approaches $\gamma =0.25$ in the turbulence state as $Ra$ increases. Just above the onset of convection, Shishkina (Phys. Rev. Fluids, vol 6, 2021, 090502) derived a length scale $\ell =H/(1+1.49\varGamma ^{-2})^{1/3}$. Our numerical study shows $Ra_{\ell }$, i.e. $Ra$ based on $\ell$, serves as a proper control parameter for heat transport above the onset with $Nu-1=0.018(1+0.34/\varGamma ^2)(Ra/Ra_{c,\varGamma }-1)$. Here $Ra_{c,\varGamma }$ represents the $\varGamma$-dependent critical $Ra$ for the onset of convection and $Nu$ is the Nusselt number. In the turbulent state, for a general scaling law of $Nu-1\sim Ra^\alpha$, we propose a length scale $\ell = H/(1+1.49\varGamma ^{-2})^{1/[3(1-\alpha )]}$. In the case of turbulent liquid metal convection with $\alpha =1/4$, our measurement shows that the heat transport will become weakly dependent on $\varGamma$ with $Ra_{\ell }\equiv Ra/(1+1.49\varGamma ^{-2})^{4/3} \ge 7\times 10^5$. Finally, once the flow becomes time-dependent, the growth rate of $Nu$ with $Ra$ declines compared with the linear growth rate in the convection state. A hysteresis is observed in a $\varGamma =1/3$ cell when the flow becomes time-dependent. Measurements of the large-scale circulation suggest the hysteresis is caused by the system switching from a single-roll-mode to a double-roll-mode in an oscillation state.
The potential threshold for dietary energy intake (DEI) that might prevent protein-energy wasting (PEW) in chronic kidney disease (CKD) is uncertain. The subjects were non-dialysis CKD patients aged ≥ 14 years who were hospitalised from September 2019 to July 2022. PEW was measured by subjective global assessment. DEI and dietary protein intake (DPI) were obtained by 3-d diet recalls. Patients were divided into adequate DEI group and inadequate DEI group according to DEI ≥ 30 or < 30 kcal/kg/d. Logistic regression analysis and restricted cubic spline were used in this study. We enrolled 409 patients, with 53·8 % had hypertension and 18·6 % had diabetes. The DEI and DPI were 27·63 (sd 5·79) kcal/kg/d and 1·00 (0·90, 1·20) g/kg/d, respectively. 69·2 % of participants are in the inadequate DEI group. Malnutrition occurred in 18·6 % of patients. Comparing with patients in the adequate DEI group, those in the inadequate DEI group had significantly lower total lymphocyte count, serum cholesterol and LDL-cholesterol and a higher prevalence of PEW. For every 1 kcal/kg/d increase in DEI, the incidence of PEW was reduced by 12·0 % (OR: 0·880, 95 % CI: 0·830, 0·933, P < 0·001). There was a nonlinear curve relationship between DEI and PEW (overall P < 0·001), and DEI ≥ 27·6 kcal/kg/d may have a preventive effect on PEW in CKD. Low DPI was also significantly associated with malnutrition, but not when DEI was adequate. Decreased energy intake may be a more important factor of PEW in CKD than protein intake.
As a member of the Scathophagidae family, Scathophaga stercoraria (S. stercoraria) is widely distributed globally and is closely associated with animal feces. It is also a species of great interest to many scientific studies. However, its phylogenetic relationships are poorly understood. In this study, S. stercoraria was found in plateau pikas for the first time. The potential cause of its presence in the plateau pikas was discussed and it was speculated that the presence of S. stercoraria was related to the yak feces. In addition, 2 nuclear genes (18SrDNA and 28SrDNA), 1 mitochondrial gene (COI), and the complete mitochondrial genome of S. stercoraria were sequenced. Phylogenetic trees constructed based on 13 Protein coding genes (13PCGs), 18S and 28S rDNA showed that S. stercoraria is closely related to the Calliphoridae family; phylogenetic results based on COI suggest that within the family Scathophagidae, S. stercoraria is more closely related to the genus Leptopa, Micropselapha, Parallelomma and Americina. Divergence times estimated using the COI gene suggest that the divergence formation of the genus Scathophaga is closely related to changes in biogeographic scenarios and potentially driven by a combination of uplift of the Qinghai-Tibetan Plateau (QTP) and dramatic climate changes. These results provide valuable information for further studies on the phylogeny and differentiation of the Scathophaga genus in the future.
This paper retrospectively analysed the prevalence of macrolide-resistant Mycoplasma pneumoniae (MRMP) in some parts of China. Between January 2013 and December 2019, we collected 4,145 respiratory samples, including pharyngeal swabs and alveolar lavage fluid. The highest PCR-positive rate of M. pneumoniae was 74.5% in Beijing, the highest resistance rate was 100% in Shanghai, and Gansu was the lowest with 20%. The highest PCR-positive rate of M. pneumoniae was 74.5% in 2013, and the highest MRMP was 97.4% in 2019; the PCR-positive rate of M. pneumoniae for adults in Beijing was 17.9% and the MRMP was 10.48%. Among the children diagnosed with community-acquired pneumonia (CAP), the PCR-positive and macrolide-resistant rates of M. pneumoniae were both higher in the severe ones. A2063G in domain V of 23S rRNA was the major macrolide-resistant mutation, accounting for more than 90%. The MIC values of all MRMP to erythromycin and azithromycin were ≥ 64 μg/ml, and the MICs of tetracycline and levofloxacin were ≤ 0.5 μg/ml and ≤ 1 μg/ml, respectively. The macrolide resistance varied in different regions and years. Among inpatients, the macrolide-resistant rate was higher in severe pneumonia. A2063G was the common mutation, and we found no resistance to tetracycline and levofloxacin.
Soft drink consumption has become a highly controversial public health issue. Given the pattern of consumption in China, sugar-sweetened beverage is the main type of soft drink consumed. Due to containing high levels of fructose, a soft drink may have a deleterious effect on handgrip strength (HGS) due to oxidative stress, inflammation and insulin resistance. However, few studies show an association between soft drink consumption and HGS in adults. We aimed to investigate the association between soft drink consumption and longitudinal changes in HGS among a Chinese adult population. A longitudinal population-based cohort study (5-year follow-up, median: 3·66 years) was conducted in Tianjin, China. A total of 11 125 participants (56·7 % men) were enrolled. HGS was measured using a handheld digital dynamometer. Soft drink consumption (mainly sugar-containing carbonated beverages) was measured at baseline using a validated FFQ. ANCOVA was used to evaluate the association between soft drink consumption and annual change in HGS or weight-adjusted HGS. After adjusting for multiple confounding factors, the least square means (95 % CI) of annual change in HGS across soft drink consumption frequencies were −0·70 (–2·49, 1·09) for rarely drinks, −0·82 (–2·62, 0·97) for < 1 cup/week and −0·86 (–2·66, 0·93) for ≥ 1 cup/week (Pfor trend < 0·05). Likewise, a similar association was observed between soft drink consumption and annual change in weight-adjusted HGS. The results indicate that higher soft drink consumption was associated with faster HGS decline in Chinese adults.
Natural clays are often employed as substrates for heterogeneous catalysts. However, the direct use of raw clays as catalysts has received less research attention. The objective of the present study was to help fill this gap by investigating catalytic properties of raw pelagic clays (PC) collected from the Indian Ocean. The raw PC were discovered to be efficient catalysts in the reduction of 4-nitrophenol (4-NP) in the presence of NaBH4. The effects of parameters including pH values, dosages of PC, and initial concentration of 4-NP and NaBH4 on the conversion or degradation rate of 4-NP have been investigated. The 4-NP was observed to be completely degraded within 480 s under conditions of 0.10 mM 4-NP, 25.0 mM NaBH4, and 0.20 g/L PC at an initial pH value of 7.0. The apparent rate constant was evaluated to be 27.53 × 10–3 s–1. Unlike previous pseudo-first order kinetics experiments, the induction period and degradation stages were observed to occur simultaneously during the PC catalysis. The S-shaped kinetics for 4-NP conversion was found to be perfectly matched by Fermi's function, and the enzyme-like catalysis by PC was appointed to describe the kinetics. Species of Fe(III), Mn(IV), and Mn(III) in PC were found to be essential, and were partly reduced to Fe(0) and Mn(II) by NaBH4 in our reaction, contributing to rapid conversion of 4-NP to 4-aminophenol (4-AP). The raw PC was converted to magnetic PC (m-PC) particles, which made PC particles separate easily for cycling use. This discovery would also have applications in continuous flow-fluid catalysis.
We report a home-built velocity-gradient-tensor-resolved particle image velocimetry (VGTR-PIV) system which spatio-temporally resolves all components of the velocity gradient tensor. This technique is applied to the paradigmatic turbulent Rayleigh–Bénard convection system in a cylindrical cell at three representative positions, i.e. centre, side and bottom regions. The VGTR-PIV system allows us to directly measure, for the first time, the spatio-temporally resolved energy dissipation rate and enstrophy in turbulent thermal convection. In the experiment, the Rayleigh number $Ra$ varied in the range $2 \times 10^8 \leqslant Ra \leqslant 8 \times 10^9$ and the Prandtl number $Pr$ was fixed at $Pr = 4.34$. Compared with the fully resolved energy dissipation rate $\varepsilon$, the pseudo-dissipation provides the best estimate within $3\,\%$, the planar (two-dimensional) surrogate has a larger relative error and the one-dimensional surrogate leads to the largest error. The power-law scalings of the time-averaged energy dissipation rate with the Rayleigh number follow $\langle \varepsilon _c \rangle _t / (\nu ^3 H^{-4}) = 9.86 \times 10^{-6} Ra^{1.54 \pm 0.02}$, $\langle \varepsilon _s \rangle _t / (\nu ^3 H^{-4}) = 9.26 \times 10^{-3} Ra^{1.25 \pm 0.02}$ and $\langle \varepsilon _b \rangle _t / (\nu ^3 H^{-4}) = 2.70 \times 10^{-2} Ra^{1.23 \pm 0.02}$ in the centre, side and bottom regions, respectively where $\nu$ is dynamic viscosity and $H$ is cell height. These scaling relations, along with our earlier measured time-averaged energy dissipation rate at the bottom wall surface $\langle \varepsilon _w \rangle _t / (\nu ^3 H^{-4}) = 9.65 \times 10^{-2} Ra^{1.25 \pm 0.02}$ (J. Fluid Mech., vol. 947, 2022, A15), provide important constraints against which theoretical models may be tested. For the centre and side locations in the convection cell, the probability density functions (p.d.f.s) of the energy dissipation rate and enstrophy both follow a stretched exponential distribution. For the bottom region, the p.d.f.s of dissipation and enstrophy exhibit a stretched exponential distribution outside the viscous boundary layer and an exponential distribution inside the viscous boundary layer. It is also found that extreme events with high dissipation are the most intermittent in the side region, whereas the bottom region is less intermittent than the cell centre.
As an environmental factor, temperature impacts the distribution of species and influences interspecific competition. The molecular chaperones encoded by small heat shock proteins (sHsps) are essential for rapid, appropriate responses to environmental stress. This study focuses on Hsp20.8, which encodes a temperature-responsive sHsp in Liriomyza trifolii, an insect pest that infests both agricultural and ornamental crops. Hsp20.8 expression was highest at 39℃ in L. trifolii pupae and adults, and expression levels were greater in pupae than in adults. Recombinant Hsp20.8 was expressed in Escherichia coli and conferred a higher survival rate than the empty vector to bacterial cells exposed to heat stress. RNA interference experiments were conducted using L. trifolii adults and prepupae and the knockdown of Hsp20.8 expression increased mortality in L. trifolii during heat stress. The results expand our understanding of sHsp function in Liriomyza spp. and the ongoing adaptation of this pest to climate change. In addition, this study is also important for predicting the distribution of invasive species and proposing new prevention and control strategies based on temperature adaptation.
In the soils of western Jilin Province in northeastern China, some significant gaps have been observed between the fraction of the soil existing as clay-size particles (<0.002 mm) and the amount attributable to crystalline clay minerals, and that the relative proportions of crystalline clay minerals to the total clay-size fraction (CP) apparently varies with latitude. The purpose of the present study was to identify the reason for this discrepancy and to explain the dependence on latitude. The grain sizes and mineral compositions of the whole soils from western Jilin Province, China, were analyzed by laser particle-size analysis (LPSA) and X-ray diffraction (XRD), and the <0.002 mm particle-size fraction was analyzed by XRD and X-ray fluorescence (XRF). The results confirmed that the percentage gaps between the clay fraction and clay minerals increased with increasing latitude. The theoretical illite percentage calculated from K2O content was compared with the illite percentage measured by XRD, and the results suggested that the measured illite accounted for only a small proportion of the theoretical illite. Structures of some special minerals below the identification threshold of XRD was suggested to be the reason for the percent gaps. The grain size and mineral crystallization both changed with latitude: the soil particle size and the CP decreased. In addition, clay minerals were more sensitive to climate than particle sizes were, and the CP of clay minerals in the soils within 0~180 cm depth all decreased with increasing latitude; however, the grain size showed patterns with latitude only in relatively shallow soil layers. The present study provides a reference and error analysis for the testing of clay minerals in alpine regions, and more suitable methods may be considered for development of clay-mineral testing in future studies.
Soil aggregates consist of sand, silt, and clay size particles. Many of the clay size particles in soils are clay minerals, which actively influence soil behavior. The properties of clay minerals may change significantly as soil particle size decreases to the nanoscale; however, little information is available about these properties for the Ultisols in China. In the present study, the clay mineral components and structural characteristics of four particle-size fractions (i.e., <2000, 450–2000, 100–450, and 25–100 nm) of two Ultisol samples (Ult-1 and Ult-2) were investigated using elemental analysis, X-ray diffraction, Fouriertransform infrared spectroscopy, and thermal analysis. The molar SiO2 to Al2O3 ratios were lower in the nanoscale particle-size fraction (25–100 nm) than in the 450–2000 and <2000 nm fractions. This indicates greater desilicification and allitization of the smaller Ultisol particles. Furthermore, the Fe oxide and Al oxide contents increased and reached a maximum level in the 25–100 nm fraction of the two Ultisols. Goethite was mainly found in the 100–450 nm and 25–100 nm fractions. The dominant clay minerals in the Ultisol 25–100 nm fraction were kaolinite and illite with a small amount of a hydroxy-interlayered mineral in Ult-1 and gibbsite in Ult-2. The kaolinite crystallinity decreased as particle size decreased. The low crystallinity of the kaolinite in the A horizon 25–100 nm fraction was attributed to a reduction in the thickness of coherent scattering domains, as well as to decreases in OH groups and the dimensions of octahedral AlO6 sheets. A determination of the chemical and mineralogic properties of the different size fractions of the Ultisols is important to understand the desilicification and Al and Fe oxide enrichment mechanisms during soil formation. The significance of these results can help to reveal the nanoscale transformations of clay minerals. Analysis of clay mineral compositions in nanoparticles can provide the additional data needed to understand the adsorption and mobility of nutrients and pollutants.
This study aimed to investigate the structural and metabolic changes in cumulus cells of underweight women and their effects on oocyte maturation and fertilization. The cytoplasmic ultrastructure was analyzed by electron microscopy, mitochondrial membrane potential by immunofluorescence, and mitochondrial DNA copy number by relative quantitative polymerase chain reaction. The expression of various proteins including the oxidative stress-derived product 4-hydroxynonenal (4-HNE) and autophagy and apoptosis markers such as Vps34, Atg-5, Beclin 1, Lc3-I, II, Bax, and Bcl-2 was assessed and compared between groups. Oocyte maturation and fertilization rates were lower in underweight women (P < 0.05), who presented with cumulus cells showing abnormal mitochondrial morphology and increased cell autophagy. Compared with the mitochondrial DNA copies of the control group, those of the underweight group increased but not significantly. The mitochondrial membrane potential was similar between the groups (P = 0.8). Vps34, Atg-5, Lc3-II, Bax, and Bcl-2 expression and 4-HNE levels were higher in the underweight group compared with the control group (P < 0.01); however, the Bax/Bcl-2 ratio was lower in the underweight group compared with the control group (P = 0.031). Additionally, Beclin 1 protein levels were higher in the underweight group compared with the control group but without statistical significance. In conclusion, malnutrition and other conditions in underweight women may adversely affect ovulation, and the development, and fertilization of oocytes resulting from changes to the intracellular structure of cumulus cells and metabolic processes. These changes may lead to reduced fertility or unsatisfactory reproduction outcomes in women.
Retropharyngeal lymphadenectomy is challenging. This study investigated a minimally invasive approach to salvage retropharyngeal lymphadenectomy in patients with nasopharyngeal carcinoma.
Methods
An anatomical study of four fresh cadaveric heads was conducted to demonstrate the relevant details of retropharyngeal lymphadenectomy using the endoscopic transoral medial pterygomandibular fold approach. Six patients with nasopharyngeal cancer with retropharyngeal lymph node recurrence, who underwent retropharyngeal lymphadenectomy with the endoscopic transoral medial pterygomandibular fold technique at the Eye and ENT Hospital of Fudan University from July to December 2021, were included in this study.
Results
The anatomical study demonstrated that the endoscopic transoral medial pterygomandibular fold approach offers a short path and minimally invasive approach to the retropharyngeal space. The surgical procedure was well tolerated by all patients, with no significant post-operative complications.
Conclusion
The endoscopic transoral medial pterygomandibular fold approach is safe and efficient for retropharyngeal lymphadenectomy.
We report an experimental and numerical study on Rayleigh–Bénard convection in a slender rectangular geometry with the aspect ratio $\varGamma$ varying from 0.05 to 0.3 and a Rayleigh number range of $10^5\leqslant Ra\leqslant 3\times 10^9$. The Prandtl number is fixed at $Pr=4.38$. It is found that the onset of convection is postponed when the convection domain approaches the quasi-one-dimensional limit. The onset Rayleigh number shows a $Ra_c=328\varGamma ^{-4.18}$ scaling for the experiment and a $Ra_c=810\varGamma ^{-3.95}$ scaling for the simulation, both consistent with a theoretical prediction of $Ra_c\sim \varGamma ^{-4}$. Moreover, the effective Nusselt–Rayleigh scaling exponent $\beta =\partial (\log Nu)/\partial (\log Ra)$ near the onset of convection also shows a rapid increase with decreasing $\varGamma$. Power-law fits to the experimental and numerical data yield $\beta =0.290\varGamma ^{-0.90}$ and $\beta =0.564\varGamma ^{-0.92}$, respectively. Near onset, the flow shows a stretched cell structure. In this regime, the velocity and temperature variations in a horizontal cross-section are found to be almost invariant with height in the core region of a slender domain. As the Rayleigh number increases, the system evolves from the viscous dominant regime to a plume-controlled one, a feature of which is enhancement in the heat transport efficiency. Upon further increase of $Ra$, the flow comes back to the classical boundary-layer-controlled regime, in which the quasi-one-dimensional geometry has no apparent effect on the global heat transfer.
Morin suggested that one of the reasons for the difficulty in standardizing graphic codes is that the production of spoken language reduces the need for graphic codes. Here we try to extend their claims from a psychological perspective, which allows us to conclude that the puzzle of ideography is perhaps related to human psychological traits and psychological evolution.
To evaluate the feasibility and safety of employing a Eustachian tube video endoscope with a supporting balloon as a viable treatment and examination option for patients with Eustachian tube dysfunction.
Methods
A study involving nine fresh human cadaver heads was conducted to investigate the potential of balloon dilatation Eustachian tuboplasty using a Eustachian tube video endoscope and a supporting balloon catheter. The Eustachian tube cavity was examined with the Eustachian tube video endoscope during the procedure, which involved the dilatation of the cartilaginous portion of the Eustachian tube with the supporting balloon catheter.
Results
The utilisation of the Eustachian tube video endoscope in conjunction with the supporting balloon catheter demonstrated technical ease during the procedure, with no observed damage to essential structures, particularly the Eustachian tube cavity.
Conclusion
This newly introduced method of dilatation and examination of the Eustachian tube cavity using a Eustachian tube video endoscope and the supporting balloon is a feasible, safe procedure.