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Studies on the evolution of characteristics and dynamic mechanisms of dry/wet status in global arid regions are contradictory. We systematically assessed the evolution and drivers of dry/wet status in global arid regions from a paleoclimate perspective using observational datasets, paleoclimate records, and climate model simulations from Paleoclimate Model Intercomparison Project Phase 4 (PMIP4)-Coupled Model Intercomparison Project Phase 6 (CMIP6) and PMIP3-CMIP5. Our results show that climate change during the last glacial maximum (LGM) provides a reverse analog for the near-future climate in global arid regions. The notable migration of the subtropical high during the LGM profoundly altered the atmospheric circulation and influenced dry/wet status in global arid regions. The multimodel ensembles project that under the shared socioeconomic pathway (SSP) 8.5 scenario, nonuniform heating induced by polar-amplified warming will introduce northward migration of the subtropical high. The resulting reduction in subtropical precipitation will lead to expansion of global arid regions under global warming, which is consistent with previous studies based on atmospheric aridity.
Serotonin (5-hydroxytryptamine, 5-HT) is a key monoamine neurotransmitter in insects, which regulates neural functions and influences various developmental and physiological processes by binding to its receptors. In this study, we investigate the molecular characteristics, phylogenetic relationships, and expression patterns of the 5-HT7 receptor (Cf5-HT7) in Chrysopa formosa, with a focus on its potential involvement in developmental and diapause regulation. The Cf5-HT7 gene was identified and cloned from the C. formosa transcriptome, revealing an open reading frame of 1788 bp encoding a 596 amino acid protein. Sequence analysis confirmed that Cf5-HT7 is a typical class A G protein-coupled receptor, characterised by seven transmembrane domains and several post-translational modifications, including palmitoylation and N-glycosylation sites. Phylogenetic analysis revealed that Cf5-HT7 is most closely related to the 5-HT7 receptor from Chrysoperla carnea, with high conservation of key motifs involved in ligand binding and receptor activation. Expression analysis across different developmental stages of C. formosa showed that Cf5-HT7 is highly expressed in the first instar larvae, with significant upregulation observed during the prepupal stage. Under diapause-inducing conditions, Cf5-HT7 expression is modulated in a stage-specific manner, showing a marked decrease at the onset of diapause, followed by a significant increase during the mid-to-late diapause maintenance phase. These findings suggest that it plays a pivotal role in regulating development and diapause processes in C. formosa, offering new insights into the molecular mechanisms governing insect life cycle transitions. This study lays the groundwork for future research into the functional roles of 5-HT7 receptors in insect physiology and their potential applications in manipulating diapause.
EXOSC10 is an exosome-associated ribonuclease that degrades and processes a wide range of transcripts in the nucleus. The initial segment (IS) of the epididymis is crucial for sperm transport and maturation in mice by affecting the absorption and secretion that is required for male fertility. However, the role of EXOSC10 ribonuclease-mediated RNA metabolism within the IS in the regulation of gene expression and sperm maturation remains unknown. Herein, we established an Exosc10 conditional knockout (Exosc10 cKO) mouse model by crossing Exosc10F/F mice with Lcn9-Cre mice which expressed recombinase in the principal cells of IS as early as post-natal day 17. Morphological and histological analyses revealed that Exosc10 cKO males had normal spermatogenesis and development of IS. Moreover, the sperm concentration, morphology, motility, and frequency of acrosome reactions in the cauda epididymides of Exosc10 cKO mice were comparable with those of control mice. Thus, Exosc10 cKO males had normal fertility. Collectively, our genetic mouse model and findings demonstrate that loss of EXOSC10 in the IS of epididymis is dispensable for sperm maturation and male fertility.
I have an idea that some men are born out of their due place. Accident has cast them amid certain surroundings, but they have always a nostalgia for a home they know not. They are strangers in their birthplace … Perhaps it is this sense of strangeness that sends men far and wide in the search for something permanent, to which they may attach themselves … Sometimes a man hits upon a place to which he mysteriously feels that he belongs …
Let $[a_1(x),a_2(x),a_3(x),\ldots ]$ be the continued fraction expansion of an irrational number $x\in [0,1)$. We are concerned with the asymptotic behaviour of the product of consecutive partial quotients of x. We prove that, for Lebesgue almost all $x\in [0,1)$,
We also study the Baire category and the Hausdorff dimension of the set of points for which the above liminf and limsup have other different values and similarly analyse the weighted product of consecutive partial quotients.
Accurate tracking and reconstruction of surgical scenes is a critical enabling technology toward autonomous robotic surgery. In endoscopic examinations, computer vision has provided assistance in many aspects, such as aiding in diagnosis or scene reconstruction. Estimation of camera motion and scene reconstruction from intra-abdominal images are challenging due to irregular illumination and weak texture of endoscopic images. Current surgical 3D perception algorithms for camera and object pose estimation rely on geometric information (e.g., points, lines, and surfaces) obtained from optical images. Unfortunately, standard hand-crafted local features for pose estimation usually do not perform well in laparoscopic environments. In this paper, a novel self-supervised Surgical Perception Stereo Visual Odometer (SPSVO) framework is proposed to accurately estimate endoscopic pose and better assist surgeons in locating and diagnosing lesions. The proposed SPSVO system combines a self-learning feature extraction method and a self-supervised matching procedure to overcome the adverse effects of irregular illumination in endoscopic images. The framework of the proposed SPSVO includes image pre-processing, feature extraction, stereo matching, feature tracking, keyframe selection, and pose graph optimization. The SPSVO can simultaneously associate the appearance of extracted feature points and textural information for fast and accurate feature tracking. A nonlinear pose graph optimization method is adopted to facilitate the backend process. The effectiveness of the proposed SPSVO framework is demonstrated on a public endoscopic dataset, with the obtained root mean square error of trajectory tracking reaching 0.278 to 0.690 mm. The computation speed of the proposed SPSVO system can reach 71ms per frame.
Previous cross-sectional and case–control studies have proposed that decreased vitamin D levels are positively correlated with the risk of suicidality in adults. However, limited studies have examined the association between vitamin D and suicidality in adolescents. This study aimed to investigate the relationship between serum vitamin D and suicidality risk among early adolescents.
Methods
Data were obtained from a Chinese early adolescent cohort. In this cohort, seventh-grade students from a middle school in Anhui Province were invited to voluntarily participate in the baseline assessments and provide peripheral blood samples (in September 2019). The participants were followed up annually (in September 2020 and September 2021). Serum 25-hydroxyvitamin D [25(OH)D] and vitamin D–related single-nucleotide polymorphisms at baseline were measured in November 2021. Traditional observational and Mendelian randomization (MR) analyses were performed to examine the relationship between serum 25(OH)D at baseline and the risk of baseline and incident suicidality (i.e., suicidal ideation [SI], plans and attempts).
Results
Traditional observational analysis did not reveal a significant linear or non-linear association of serum 25(OH)D concentration with the risks of baseline and 2-year incident suicidality in the total sample (P > .05 for all). Sex-stratified analysis revealed a non-linear association between the 25(OH)D concentration and the risk of baseline SI in women (Poverall = .002; Pnon-linear = .001). Moreover, the risk of baseline SI in the 25(OH) insufficiency group was lower than that in the 25(OH) deficiency group in the total sample (odds ratio [OR] = 0.69, 95% confidence interval [CI] = 0.51–0.92, P = .012). This difference remained significant in women (OR = 0.59, 95% CI = 0.40–0.87, P = .008) but not in men (OR = 0.78, 95% CI = 0.53–1.15, P = .205). Additionally, both linear and non-linear MR analyses did not support the causal effect of serum 25(OH)D concentration on the risk of baseline, 1-year and 2-year incident suicidality (P > .05 for all).
Conclusions
This study could not confirm the causal effect of vitamin D on suicidality risk among Chinese early adolescents. Future studies must confirm these findings with a large sample size.
To explore the cross-sectional and longitudinal association between vitamin D and depressive symptoms across early adolescence.
Methods
This longitudinal study included 1607 early adolescents [mean (s.d.) age, 12.49 years; 972 (60.5%) males] from the Chinese Early Adolescents Cohort, recruited from a middle school in Anhui Province and followed up annually (2019–2021). Serum 25(OH)D levels were measured in both 2019 and 2021. Self-reports on depression were assessed at each of three time points from 2019 to 2021.
Results
In the whole sample, higher baseline serum 25(OH)D levels were linked with a lower risk of cumulative incident depression within two-year follow-ups (adjusted RR = 0.97, 95% CI 0.94–0.99) and the increasing trajectory of depression symptoms across the three waves (adjusted RR = 0.97, 95% CI 0.95–0.99). Baseline vitamin D deficiency (VDD) (adjusted RR = 1.50, 95% CI 1.10–2.05) were associated with an increased risk for the increasing trajectory of depression symptoms across the three waves. Remitted VDD was positively related to one dichotomous depression symptoms across three waves (adjusted OR 2.15, 95% CI 1.15–4.01). The above-mentioned significant association was also found in males. Additionally, baseline VDD (adjusted OR 1.59, 95% CI 1.04–2.44) and persistent VDD (adjusted OR 1.58, 95% CI 1.02–2.60) were linked to an increased risk of having two dichotomous depression symptoms only in males.
Conclusions
Our results highlight a prospective association between baseline vitamin D and depression risk in early adolescents. Additionally, a male-specific association between vitamin D and depression risk was observed. Our findings support a potential beneficial effect of vitamin D supplementation in reducing depression risk in early adolescents.
Despite increasing knowledge on the neuroimaging patterns of eating disorder (ED) symptoms in non-clinical populations, studies using whole-brain machine learning to identify connectome-based neuromarkers of ED symptomatology are absent. This study examined the association of connectivity within and between large-scale functional networks with specific symptomatic behaviors and cognitions using connectome-based predictive modeling (CPM).
Methods
CPM with ten-fold cross-validation was carried out to probe functional networks that were predictive of ED-associated symptomatology, including body image concerns, binge eating, and compensatory behaviors, within the discovery sample of 660 participants. The predictive ability of the identified networks was validated using an independent sample of 821 participants.
Results
The connectivity predictive of body image concerns was identified within and between networks implicated in cognitive control (frontoparietal and medial frontal), reward sensitivity (subcortical), and visual perception (visual). Crucially, the set of connections in the positive network related to body image concerns identified in one sample was generalized to predict body image concerns in an independent sample, suggesting the replicability of this effect.
Conclusions
These findings point to the feasibility of using the functional connectome to predict ED symptomatology in the general population and provide the first evidence that functional interplay among distributed networks predicts body shape/weight concerns.
Sources and implications of black carbon (BC) and mineral dust (MD) on two glaciers on the central Tibetan Plateau were estimated based on in situ measurements and modeling. The results indicated that BC and MD accounted for ~11 ± 1% and 4 ± 0% of the albedo reduction relative to clean snow, while the radiative forcing varied between 11 and 196 and 1–89 W m−2, respectively. Assessment of BC and MD contributions to the glacier melt can reach up 88 to 434 and 35 to 187 mm w.e., respectively, contributing ~9–23 and 4–10% of the total glacier melt. A footprint analysis indicated that BC and MD deposited on the glaciers originated mainly from the Middle East, Central Asia, North China and South Asia during the study period. Moreover, a potentially large fraction of BC may have originated from local and regional fossil fuel combustion. This study suggests that BC and MD will enhance glacier melt and provides a scientific basis for regional mitigation efforts.
In order to investigate the benefits of compound waterways more fully, this study reveals vessel navigational mode and traffic conflicts in a compound waterway through a case analysis, following which a type of simplified prototype of a compound waterway is proposed and three key conflict areas are specified. Based on the three key sub-models of slot allocation for vessels in a waterway entrance, traffic flow conversion of a main and auxiliary waterway in a precautionary area, and traffic flow coordination of division and confluence in a Y crossing area, a vessel traffic scheduling optimisation model is presented, with the minimum waterway occupancy time and minimum total waiting time of vessels as the objective. Furthermore, a multi-objective genetic algorithm is proposed to solve the model and a simulation experiment is carried out. By analysing the optimised solution and comparing it with other scheduling schemes in common use, the results indicate that this method can effectively improve navigation safety and efficiency in a compound waterway.
The duration of untreated psychosis (DUP) has been widely studied. However, for individuals with attenuated psychosis syndrome (APS), it is unclear whether the duration of untreated prodromal symptoms (DUPrS) also has a negative effect on the progression of psychosis. Our aim was to identify demographic and clinical factors contributing to the DUPrS in a large sample of individuals with APS, and to evaluate the association between DUPrS and the conversion to psychosis.
Method
A sample of 391 individuals with APS, who were identified through a structured interview for prodromal syndromes, were included in this study, of whom a total of 334 patients had completed at least a 1-year clinical follow-up. A total of 57 individuals had converted to psychosis.
Results
The average DUPrS was 4.8 months for the whole sample. Individuals with a longer DUPrS were likely to be men, non-local residents, with abnormal thought symptoms, a higher severity level of negative symptoms, the lower severity level of general symptoms, and lower level of general function before the onset of attenuated positive symptoms. A DUPrS of less than 2 months, or more than 6 months, lowered the risk for conversion to psychosis.
Conclusions
Our data suggested that the association between the DUPrS and outcome in individuals with APS were likely to be different, which is either long or short DUPrS was not related to future psychosis onset. Individuals with APS were more likely to have a group of features associated with a longer DUPrS.
Three gravity cores (LZK1, ZKA4, and CSJA6) from the incised Yangtze paleo-valley comprise a thick sequence of the post-glacial deposit. Nineteen genera (26 species) of the benthic foraminifers are described from these cores, with detailed down-core foraminiferal variations to investigate their paleoenvironmental implications. Three foraminiferal assemblages are recognized for the lower, middle, and upper parts of the cores respectively. The lower part is dominated by Ammonia beccarii var. and Florilus decorus with lower abundance and diversity. In the middle part, the foraminifers are abundant and diverse, dominated by both Ammonia beccarii var. and Elphidium advenum. Cavarotalia annectens, Pararotalia nipponica, and porcellaneous benthic foraminiferal forms are always present, sometimes abundant. The upper part is characterized by the Ammonia beccarii-Elphidium magellanicum assemblage, except for the Core ZKA4, which is barren of foraminifers in this interval. AMS 14C dates and foraminiferal assemblages both confirm that the transgression-regression sequence in these cores belongs to the “Ammonia transgression” during the Holocene. In addition to documenting the post-glacial sea-level fluctuations, the benthic foraminifers also reflect a warmer climate during the early–middle Holocene. The foraminiferal differences among the three cores can be used to interpret the influence of seawater during the post-glacial sea-level fluctuations. The area in the vicinity of Core ZKA4 was affected by marine water only during the middle Holocene, which was much shorter than the areas of the other cores.
The effects of magnetic field on the austenite formation and grain size were studied by applying high magnetic field during the different stages. Optical microscopy and scanning electron microscopy were used to characterize the microstructure evolution for the samples treated without and with magnetic field. Magnetic field dramatically retards the austenite formation kinetics including pearlite to austenite transformation and cementite dissolution. The austenite grain size is enlarged by the magnetic field applied during austenite formation and not affected by the magnetic field applied only during austenite grain coarsening. The austenite treated with magnetic field during the whole austenitization process also has a larger grain size. The changes in austenite formation kinetics and grain size are related to lower nucleation rate of austenite caused by magnetic field.
A new strategy using hyperbranched poly(amidoamine)s to functionalize CdTe quantum dots (QDs) has been described. Hyperbranched poly(amidoamine)s with amine terminals (HP-EDAMA1) were synthesized by one-pot polymerization via the coupled-monomer method and subsequently used to functionalize preformed CdTe QDs. Quite different from previous studies in which the photoluminescence of QDs was quenched by further functionalization with tailored ligands, the quantum yield of CdTe/HP-EDAMA1 nanocomposites was 2 times that of pure CdTe QDs without modification. With this versatile method, the photoluminescence quenching of QDs in the modification process by matrix materials can be effectively solved and new QDs/hyperbranched polymer nanocomposites with potential applications in biomedicine might be offered.
The crystallization process of Zr70Cu27.5Rh2.5 metallic glass was studied with Transmission Electron Microscopy (TEM). In contrast to previous studies where the precipitation of metastable icosahedral quasicrystalline (IQC) particles is of the interest, we designed the present work to focus on the nucleation process of the stable Zr2Cu crystalline phase. It has been found that the alloy consists of IQC particles distributed in amorphous matrix prior to the precipitation of the Zr2Cu stable crystalline phase and Zr2Cu nucleates from the amorphous matrix. The encounter of the IQC phase with Zr2Cu transforms the former into the latter so quickly that no interface between them was found in the present experiment. These insights provide the basis for a discussion of the stability of metallic glasses and the IQC particles.
The transformation behavior from glassy state was investigated in Zr- and Hf-based glassy alloys. The primary phases are metastable face-centered-cubic (fcc) Zr2Ni and fcc Hf2Ni phases in the Zr65Al7.5Ni10Cu17.5 and Hf65Al7.5Ni10Cu17.5 glassy alloys, respectively. By substitution of 5 at.% Pd for Cu, the primary phase changes to an icosahedral quasicrystalline phase in both alloys. It is found that the addition of elements, which have a positive or weak chemical affinity with one of the constitutional elements in the Zr–Al–Ni–Cu and Hf–Al–Ni–Cu glassy alloys, is effective for the precipitation of the icosahedral phase. It is suggested that Pd plays a dominant role in an increase in the number of nucleation sites. Since an icosahedron is contained as a structure unit in the icosahedral, fcc Zr2Ni and fcc Hf2Ni phases, it is implied that these phases are correlated with the local icosahedral order. The high-resolution transmission electron microscopy images of the as-spun Zr65Al7.5Ni10Cu7.5Pd10 and Hf65Al7.5Ni10Cu12.5Pd5 alloys reveal a possibility of the existence of the icosahedral ordered regions. It is therefore, concluded that the icosahedral short- or medium-range order exists and it stabilizes the glassy state in the Zr- and Hf-based multicomponent alloys.
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