To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
We examine the dynamic interactions between the large-scale coherent motion and the small-scale turbulence in the passive scalar field of a circular cylinder wake, where the coherent motion exhibits strong periodicity. A combination of four X-wires and four cold wires was used to simultaneously measure the three velocity and temperature fluctuations at nominally the same location. Measurements were taken at $x/d=10$, 20 and 40 in the mean shear plane at Reynolds number 2500, based on the cylinder diameter $d$ and the free-stream velocity. The phase-averaging technique is used to distinguish the large-scale coherent motion from the stochastic motion, enabling the construction of phase-averaged structure functions of the passive scalar in the scale phase plane. The maximum of the coherent scalar $\tilde {\theta }$ closely aligns with the minima of the phase-averaged strain $\langle S \rangle$ and the vortex centre, suggesting that heat is contained within the interior of the vortex. The scale-by-scale distributions of the scalar variance and the streamwise velocity variance exhibit a similar phase dependence associated with the coherent motion. This dependence is perceptible even at the smallest scales. However, as the distance from the cylinder increases, the perceivable scale range decreases and eventually disappears. An expression is formulated to describe the time-averaged second-order structure function of coherent scalar and the time-averaged second-order mixed structure function between the coherent scalar and coherent streamwise velocity at $x/d= 10$ and 20, where the coherent motion is prominent. Furthermore, the scale-by-scale contribution of the coherent scalar variance to the total scalar variance is evaluated. Also, we derive the scale-by-scale scalar variance transport equations that account for the coherent motion in both general and isotropic formulations. Assuming local isotropy, it is found that the equation agrees approximately with the experimental data across all scales at $x/d= 40$. Finally, the differences between the scale-by-scale transport equation for the stochastic scalar variance and that for the stochastic turbulent kinetic energy are discussed.
Conceptual improvements are a significant dimension through which local moral progress occurs, both at the individual and societal levels. Michele Moody-Adams (1999) offers a narrow view of moral progress, suggesting that only a deepened understanding of complex, existing moral concepts can constitute moral progress. Consequently, she views the role of moral philosophy as limited to constructing deeper accounts of these concepts. We broaden Moody-Adams’s (1999) account by identifying three distinct types of conceptual improvements that can constitute moral progress: deepening the understanding of existing concepts, creating new concepts, and enhancing the ability to apply concepts. We support this typology with historical examples where such improvements constituted moral progress. Based on this typology, we argue that the role of moral philosophy extends beyond developing and refining moral theories to include the active creation of new concepts and the facilitation of conceptual application.
An experimental study is performed to control flow separation from a two-dimensional curved ramp using a spanwise pulsed blowing slit jet placed near the separation point of the baseline flow. The momentum-thickness-based Reynolds number $ \textit{Re}_{\theta}$ is 5700. Four control parameters are investigated, including the velocity ratio $\overline{U_{J,c}^{*}}$, duty cycle dc, dimensionless excitation frequency $f_{e}^{{*}}$ and jet blowing angle $\alpha$. The control mechanisms are found to differ from small to large jet angle. Empirical scaling analysis for $\alpha \leq 55^{\circ}$ unveils that $\Delta \overline{C_{p,e}}=f_{1}(\overline{U_{J,c}^{*}}, { d}c, f_{e}^{*}, \alpha , Re_{\theta })$ may be reduced to $\Delta \overline{C_{p,e}}/\varPi (\tau )=f_{2}(\xi )$, where $f_{1}$ and $f_{2}$ are different functions, $\Delta \overline{C_{p,e}}$ is the variation in the pressure coefficient at the end of the ramp under control, $\varPi (\tau )$ is a function of dimensionless duration $\tau$ at which the jet is closed within one excitation period, $\Delta \overline{C_{p,e}}/\varPi (\tau )$ represents the control efficiency, and $\xi$ is a scaling factor that is physically the energy ratio per unit area of the blowing jet to the mainstream. This scaling law is also found to be valid for steady jet control. Several interesting inferences can be made from this scaling law, which provides important insight into the physics of flow separation control.
Individuals with first-episode psychosis (FEP) face markedly increased excess mortality, yet the long-term trends and key contributing factors remain insufficiently characterized. This study aimed to examine long-term mortality patterns, standardized mortality ratios (SMRs), and associated factors in a FEP cohort.
Methods
This population-based cohort study included 1,389 individuals diagnosed with FEP, followed for up to 25 years. Mortality outcomes were obtained from Hong Kong’s centralized hospital database (CMS) and coroner’s court reports, with SMRs calculated. Baseline sociodemographic and clinical, as well as long-term treatment-related factors of all-cause, natural, and unnatural mortality were analyzed.
Results
Among 1,389 participants, 137 deaths (9.86%) occurred during the follow-up period with the overall SMR of 6.56 (95% CI, 5.50–7.71). The cumulative incidence rate of unnatural mortality increased sharply over the first 10 years and that of the natural cause of death started to increase after the first decade of the illness. Male gender and poorer social functioning were associated with increased all-cause mortality risk, while male gender, lower education, and baseline hospitalization raised unnatural mortality risk. Greater monthly antipsychotic variability during the first 10 years increased all-cause mortality risk in the period after the initial 10 years.
Conclusions
This 25-year follow-up study of FEP highlighted the changes in the long-term mortality pattern of FEP and thus the phase-specific needs of individuals with FEP. Therefore, it is important to integrate physical care into mental health services, as well as stage-specific and individualized care for patients with psychotic disorders to reduce long-term excess mortality.
Entrepreneurial reentry after business failure is an important area of research in the field of entrepreneurship. However, previous studies have largely overlooked the crucial role of time factors – both objective and subjective – in the context of failure and subsequent entrepreneurial endeavors. This study aims to fill this gap by examining the impact of firm lifespan on entrepreneurial reentry and the moderating effect of entrepreneurs’ temporal focus. Through manual matching across multiple databases, we obtain a sample of 368 entrepreneurs. The results show that a longer firm lifespan negatively influences entrepreneurial reentry and that a past focus further amplifies this negative relationship. This study contributes to research on the determinants of entrepreneurial reentry and provides theoretical insights into the role of time in entrepreneurial reentry.
Non-suicidal self-injury (NSSI) among adolescents severely jeopardizes their well-being and has emerged as a significant global public health challenge. However, research on the trends in NSSI among adolescents remains scarce. This study sought to uncover the evolving patterns in the severity of NSSI among adolescents and the factors that influence these patterns. The Deliberate Self-Harm Inventory was employed to measure the severity of NSSI among adolescents. Relevant studies were retrieved from both Chinese databases (CNKI, Wanfang, and VIP) and English databases (Web of Science, PubMed, Scopus, ProQuest, and Wiley). A total of 70 articles (71 studies; N = 96,382) were included in this review. The data spanned from 2007 to 2023. The analysis revealed the following: (1) Although the severity of NSSI showed a small to moderate upward trend from 2007 to 2023, this increase did not reach statistical significance. (2) No significant differences in trends were observed among Asia, Europe, and the America. (3) Adolescents with clinical samples exhibited a more pronounced upward trajectory in NSSI severity compared to those with non-clinical samples. (4) Social development indicators (GDP per capita, Human Development Index, and Internet penetration rate) and social well-being (happiness index) exhibited significant positive correlations with NSSI among adolescents. Conversely, lower social equity (higher Gini coefficient) was associated with reduced NSSI among adolescents. This study elucidated the changing trends in NSSI among adolescents and offered novel insights for the early prevention and individualized intervention of NSSI among adolescents.
MicroRNAs (miRNAs) alterations in patients with bipolar disorder (BD) are pivotal to the disease’s pathogenesis. Since obtaining brain tissue is challenging, most research has shifted to analyzing miRNAs in peripheral blood. One innovative solution is sequencing miRNAs in plasma extracellular vesicles (EVs), particularly those neural-derived EVs emanating from the brain.
Methods
We isolated plasma neural-derived EVs from 85 patients with BD and 39 healthy controls (HC) using biotinylated antibodies targeting a neural tissue marker, followed by miRNA sequencing and expression analysis. Furthermore, we conducted bioinformatic analyses and functional experiments to delve deeper into the underlying pathological mechanisms of BD.
Results
Out of the 2,656 neural-derived miRNAs in EVs identified, 14 were differentially expressed between BD patients and HC. Moreover, the target genes of miR-143-3p displayed distinct expression patterns in the prefrontal cortex of BD patients versus HC, as sourced from the PsychENCODE database. The functional experiments demonstrated that the abnormal expression of miR-143-3p promoted the proliferation and activation of microglia and upregulated the expression of proinflammatory factors, including IL-1β, IL-6, and NLRP3. Through weighted gene co-expression network analysis, a module linking to the clinical symptoms of BD patients was discerned. Enrichment analyses unveiled these miRNAs’ role in modulating the axon guidance, the Ras signaling pathway, and ErbB signaling pathway.
Conclusions
Our findings provide the first evidence of dysregulated plasma miRNAs within neural-derived EVs in BD patients and suggest that neural-derived EVs might be involved in the pathophysiology of BD through related biological pathways, such as neurogenesis and neuroinflammation.
Yiyang Dahegu rice (YyDHG) is an important agricultural specialty of Yiyang County, Jiangxi Province, and it is also a significant component of the local cultural and economic development. In this experiment, 89 samples of Dahegu rice (DHG) were collected from Jiangxi Province, including 52 samples of YyDHG and 37 samples of DHG from other regions within Jiangxi Province (oDHG). Comprehensive analysis was conducted using polyacrylamide gel electrophoresis, field phenotypic observation, population structure analysis and quality analysis. The results of variety identification indicated that the 89 samples actually comprised 52 distinct varieties, including 19 varieties of YyDHG. Population analysis has revealed rich genetic diversity among DHG varieties within Jiangxi Province, yet no significant subpopulation differentiation was observed between YyDHG and oDHG. Quality experiments demonstrated that YyDHG exhibits significant differences in appearance quality from oDHG, but no notable differences in milling quality or cooked taste and flavour. This suggests that the competitiveness of YyDHG in the market may not entirely depend on its unique quality characteristics, but rather more on its cultural value and brand effect. This experiment conducted a comprehensive analysis of the variety characteristics, genetic diversity and quality traits of YyDHG. Not only does it provide a scientific basis for the breeding and germplasm resource conservation of YyDHG, but it also holds positive implications for promoting the development of its industry.
A systematic study is conducted both experimentally and theoretically on the wake-induced vibration of an inelastic or zero structural stiffness cylinder placed behind a perfectly elastic or rigid cylinder. The mass ratio m* of the inelastic cylinder is 11.1. The spacing ratio L/D is 2.0–6.0, where L is the distance between centers of the two cylinders, and D is the cylinder diameter. The range of Reynolds number Re is 1.97 × 103–1.18 × 104. It has been found that the inelastic cylinder becomes aerodynamically elastic because the cylinder and the fluctuating wake interact, inducing an effective stiffness and thus giving rise to an aeroelastic natural frequency. This frequency depends on the added mass, fluid damping and flow-induced stiffness and is always smaller than the vortex shedding frequency, irrespective of Re and L/D. The wake-induced vibration of the inelastic cylinder may be divided into a desynchronisation branch and a galloping branch. The vibration amplitude jumps greatly at the transition from desynchronisation to galloping for L/D = 2.0–4.5 but not so for L/D = 5.0–6.0. The flow-induced stiffness is linearly correlated with Re, generally higher in the reattachment regime than in the coshedding regime and smaller in galloping than in desynchronisation. Other aspects of the inelastic cylinder are also investigated in detail, including the dependence on Re of the Strouhal numbers, hydrodynamic forces, phase lag between lift and displacement and flow characteristics.
Let $\mathcal {D}$ be a Hom-finite, Krull-Schmidt, 2-Calabi-Yau triangulated category with a rigid object R. Let $\Lambda =\operatorname {End}_{\mathcal {D}}R$ be the endomorphism algebra of R. We introduce the notion of mutation of maximal rigid objects in the two-term subcategory $R\ast R[1]$ via exchange triangles, which is shown to be compatible with the mutation of support $\tau $-tilting $\Lambda $-modules. In the case that $\mathcal {D}$ is the cluster category arising from a punctured marked surface, it is shown that the graph of mutations of support $\tau $-tilting $\Lambda $-modules is isomorphic to the graph of flips of certain collections of tagged arcs on the surface, which is moreover proved to be connected. Consequently, the mutation graph of support $\tau $-tilting modules over a skew-gentle algebra is connected. This generalizes one main result in [49].
n-3 PUFA, including ALA, EPA and DHA, are widely found in plant oils and marine organisms. These fatty acids demonstrate significant biological effects, and their adequate intake is essential for maintaining health. However, modern diets often lack sufficient n-3 PUFA, especially among populations that consume little fish or seafood, leading to a growing interest in n-3 PUFA supplementation in nutrition and health research. In recent decades, the role of n-3 PUFA in preventing and treating various diseases has gained increasing attention, particularly in cardiovascular, neurological, ophthalmic, allergic, hepatic and oncological fields. In orthopaedics, n-3 PUFA exert beneficial effects through several mechanisms, including modulation of inflammatory responses, enhancement of cartilage repair and regulation of bone metabolism. These effects demonstrate potential for the treatment of conditions such as osteoarthritis, rheumatoid arthritis, gout, osteoporosis, fractures, sarcopenia and spinal degenerative diseases. This review summarises the clinical applications of n-3 PUFA, with a focus on their research progress in the field of orthopaedics, and explores their potential in the treatment of orthopaedic diseases.
Persistent malnutrition is associated with poor clinical outcomes in cancer. However, assessing its reversibility can be challenging. The present study aimed to utilise machine learning (ML) to predict reversible malnutrition (RM) in patients with cancer. A multicentre cohort study including hospitalised oncology patients. Malnutrition was diagnosed using an international consensus. RM was defined as a positive diagnosis of malnutrition upon patient admission which turned negative one month later. Time-series data on body weight and skeletal muscle were modelled using a long short-term memory architecture to predict RM. The model was named as WAL-net, and its performance, explainability, clinical relevance and generalisability were evaluated. We investigated 4254 patients with cancer-associated malnutrition (discovery set = 2977, test set = 1277). There were 2783 men and 1471 women (median age = 61 years). RM was identified in 754 (17·7 %) patients. RM/non-RM groups showed distinct patterns of weight and muscle dynamics, and RM was negatively correlated to the progressive stages of cancer cachexia (r = –0·340, P < 0·001). WAL-net was the state-of-the-art model among all ML algorithms evaluated, demonstrating favourable performance to predict RM in the test set (AUC = 0·924, 95 % CI = 0·904, 0·944) and an external validation set (n 798, AUC = 0·909, 95 % CI = 0·876, 0·943). Model-predicted RM using baseline information was associated with lower future risks of underweight, sarcopenia, performance status decline and progression of malnutrition (all P < 0·05). This study presents an explainable deep learning model, the WAL-net, for early identification of RM in patients with cancer. These findings might help the management of cancer-associated malnutrition to optimise patient outcomes in multidisciplinary cancer care.
Patients with schizophrenia have a significantly elevated risk of mortality. Clozapine is effective for treatment-resistant schizophrenia, but its use is limited by side-effects. Understanding its association with mortality risk is crucial.
Aims
To investigate the associations of clozapine with all-cause and cause-specific mortality risk in schizophrenia patients.
Method
In this 18-year population-based cohort study, we retrieved electronic health records of schizophrenia patients from all public hospitals in Hong Kong. Clozapine users (ClozUs) comprised schizophrenia patients who initiated clozapine treatment between 2003 and 2012, with the index date set at clozapine initiation. Comparators were non-clozapine antipsychotic users (Non-ClozUs) with the same diagnosis who had never received a clozapine prescription. They were 1:2 propensity score matched with demographic characteristics and physical and psychiatric comorbidities. ClozUs were further defined according to continuation of clozapine use and co-prescription of other antipsychotics (polypharmacy). Accelerated failure time (AFT) models were used to estimate the risk of all-cause and cause-specific mortality (i.e. suicide, cardiovascular disease, infection and cancer).
Results
This study included 9,456 individuals (mean (s.d.) age at the index date: 39.13 (12.92) years; 50.73% females; median (interquartile range) follow-up time: 12.37 (9.78–15.22) years), with 2020 continuous ClozUs, 1132 discontinuous ClozUs, 4326 continuous non-ClozUs and 1978 discontinuous Non-ClozUs. Results from adjusted AFT models showed that continuous ClozUs had a lower risk of suicide mortality (acceleration factor 3.01; 99% CI: 1.41–6.44) compared with continuous Non-ClozUs. Continuous ClozUs with co-prescription of other antipsychotics exhibited lower risks of suicide mortality (acceleration factor 3.67; 1.41–9.60) and all-cause mortality (acceleration factor 1.42; 1.07–1.88) compared with continuous Non-ClozUs. No associations were found between clozapine and other cause-specific mortalities.
Conclusions
These results add to the existing evidence on the effectiveness of clozapine, particularly its anti-suicide effects, and emphasise the need for continuous clozapine use for suitable patients and the possible benefit of clozapine polypharmacy.
Noise source identification has been a long-standing challenge for decades. Although it is known that sound sources are closely related to flow structures, the underlying physical mechanisms remain controversial. This study develops a sound source identification method based on longitudinal and transverse process decomposition (LTD). Large-eddy simulations were performed on the flow around a cylinder at a Reynolds number of 3900. Using the new LTD method, sound sources in the cylinder flow were identified, and the mechanisms linking flow structures with noise generation were discussed in detail. Identifying the physical sound sources from two levels, low-order theory and high-order theory, the physical mechanism of wall sound sources was also analysed. Results indicate that the sound sources in the flow field mainly come from the leading edge, shear layer and wake region of the cylinder. The high-order theory reveals that sound sources are correlated with the spatio-temporal evolution of enstrophy, vortex stretching and surface deformation processes, this reflecting the coupling between transversal and longitudinal flow fields. The boundary thermodynamic flux and boundary dilatation flux distribution of the cylinder were analysed. Results indicate that the wall sound sources mainly come from the separation point and have a disorderly distribution on the leeward side of the cylinder, which is the main region where longitudinal variables enter the fluid from the wall surface, and the wall sound source is related to the boundary enstrophy flux.
This study presents a novel investigation into the vortex dynamics of flow around a near-wall rectangular cylinder based on direct numerical simulation at $Re=1000$, marking the first in-depth exploration of these phenomena. By varying aspect ratios ($L/D = 5$, $10$, $15$) and gap ratios ($G/D = 0.1$, $0.3$, $0.9$), the study reveals the vortex dynamics influenced by the near-wall effect, considering the incoming laminar boundary layer flow. Both $L/D$ and $G/D$ significantly influence vortex dynamics, leading to behaviours not observed in previous bluff body flows. As $G/D$ increases, the streamwise scale of the upper leading edge (ULE) recirculation grows, delaying flow reattachment. At smaller $G/D$, lower leading edge (LLE) recirculation is suppressed, with upper Kelvin–Helmholtz vortices merging to form the ULE vortex, followed by instability, differing from conventional flow dynamics. Larger $G/D$ promotes the formation of an LLE shear layer. An intriguing finding at $L/D = 5$ and $G/D = 0.1$ is the backward flow of fluid from the downstream region to the upper side of the cylinder. At $G/D = 0.3$, double-trailing-edge vortices emerge for larger $L/D$, with two distinct flow behaviours associated with two interactions between gap flow and wall recirculation. These interactions lead to different multiple flow separations. For $G/D = 0.9$, the secondary vortex (SV) from the plate wall induces the formation of a tertiary vortex from the lower side of the cylinder. Double-SVs are observed at $L/D = 5$. Frequency locking is observed in most cases, but is suppressed at $L/D = 10$ and $G/D = 0.9$, where competing shedding modes lead to two distinct evolutions of the SV.
Can Chinese companies innovate in cutting-edge technology? It is a question many have been asking in the last few years as the size and dynamism of China's economy become apparent. This article focuses on the development of Chinese companies in the information and telecommunication sectors of industry, conventionally known as “Information Communication Technology” (ICT), among the most dynamic, profitable and globalized industries.
Old Kashgar is not long for this world. Quake fear, anxiety over ethnic unrest, and pursuit of development have spurred the authorities to launch a large-scale plan to demolish and redevelop 85% of the Old City.
There has been considerable criticism of the project among Kashgar residents and in the world world media, but it has done little to stop the project. This month's Phoenix Weekly contains an interesting cover feature on life in the Old City and how it may change in the future. The story is a little oversold based on the coverline: “The Shadow of ‘East Turkestan’ on China's Strategic Anti-Terrorism City,” as most of the feature is about everyday life as opposed to terrorism.
Bovine mastitis harms milk quality and cattle health. Val-Pro-Pro (VPP) and Ile-Pro-Pro (IPP) are well-known milk-derived bioactive peptides with anti-inflammatory activity. However, the impact of VPP and IPP on mastitis remain unknown. This study aimed to investigate the anti-inflammatory effects and the underlying mechanisms of VPP and IPP in lipopolysaccharide (LPS)-induced inflammation. When cells were treated with LPS (1 µg/mL) for 24 h, the protein levels of pro-inflammatory factors (tumor necrosis factor-α (TNF-α), interleukin(IL)-1β and IL-6)) and chemokine (monocyte chemotactic protein-1 (MCP-1)) were markedly increased, and the protein level of anti-inflammatory cytokine (IL-10) was reduced. Both VPP and IPP with concentrations of 50 and 100 µM reversed these phenomena and further inhibited the protein expression of β-casein induced by LPS. In a mouse mastitis model, different concentrations of VPP and IPP (300, 600 µM/kg) pretreatment alleviated histopathological lesions in the mammary gland and suppressed the mRNA expression of TNFα, IL1β, and IL6 induced by LPS. VPP and IPP also maintained the integrity of the blood–milk barrier in mice. RNA-seq analyses indicated that enriched phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) and mitogen-activated protein kinase (MAPK) signaling pathways likely contribute to the changes observed (P < 0.05 and |log2 fold change (FC)| ≥ 1). Notably, fibronectin was identified as an important hub by protein–protein interaction (PPI) analysis and molecular docking combined with molecular dynamics simulation. In summary, VPP and IPP exerted a protective effect on LPS-induced inflammation by regulating PI3K/AKT signaling pathway via fibronectin.
We investigate the natural oscillations of sessile drops with a central trapped bubble on a plane using linear potential flow theory, considering both free and pinned contact lines. The system is governed by the contact angle $\alpha$ and the ratio $\tau$ of inner to outer contact line radii. For bubble-containing (BC) hemispherical drops with free contact lines (referred to as free BC semi-drops), the modes mirror half of those in concentric spherical BC drops due to plane symmetry. These modes are labelled ‘plus’ (with greater inner surface deformation) and ‘minus’ (with greater outer surface deformation). As $\tau \to 0$, minus modes converge to those of bubble-free drops. Results show that varying $\alpha$ from $90^\circ$ or pinning the contact line in free BC semi-drops alters the topology of spectral lines, turning original crossings of spectral lines between minus and plus modes into avoided crossings. This shift causes minus and plus modes to form spectral trends with avoided crossings, maintaining their original spectral shapes. In an avoided crossing, two coupled modes cannot be classified as plus or minus due to their comparable inner and outer surface deformations, resulting in mode beating when both are excited, as confirmed by our direct numerical simulations. This study on the impact of inner bubbles on the spectrum may help in predicting bubble size in opaque sessile drops.