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Klebsiella pneumoniae is a common pathogen associated with nosocomial infections and is characterised serologically by capsular polysaccharide (K) and lipopolysaccharide O antigens. We surveyed a total of 348 non-duplicate K. pneumoniae clinical isolates collected over a 1-year period in a tertiary care hospital, and determined their O and K serotypes by sequencing of the wbb Y and wzi gene loci, respectively. Isolates were also screened for antimicrobial resistance and hypervirulent phenotypes; 94 (27.0%) were identified as carbapenem-resistant (CRKP) and 110 (31.6%) as hypervirulent (hvKP). isolates fell into 58 K, and six O types, with 92.0% and 94.2% typeability, respectively. The predominant K types were K14K64 (16.38%), K1 (14.66%), K2 (8.05%) and K57 (5.46%), while O1 (46%), O2a (27.9%) and O3 (11.8%) were the most common. CRKP and hvKP strains had different serotype distributions with O2a:K14K64 (41.0%) being the most frequent among CRKP, and O1:K1 (26.4%) and O1:K2 (17.3%) among hvKP strains. Serotyping by gene sequencing proved to be a useful tool to inform the clinical epidemiology of K. pneumoniae infections and provides valuable data relevant to vaccine design.
Toxoplasma gondii infections are common in humans and animals worldwide. Domestic free-range chickens (Gallus domesticus) are excellent sentinels of environmental contamination with T. gondii oocysts because they feed on the ground. Chickens can be easily infected with T. gondii; however, clinical toxoplasmosis is rare in these hosts. Chickens are comparatively inexpensive and thus are good sentinel animals for T. gondii infections on the farms. Here, the authors reviewed prevalence, the persistence of infection, clinical disease, epidemiology and genetic diversity of T. gondii strains isolated from chickens worldwide for the past decade. Data on phenotypic and molecular characteristics of 794 viable T. gondii strains from chickens are discussed, including new data on T. gondii isolates from chickens in Brazil. This paper will be of interest to biologists, epidemiologists, veterinarians and parasitologists.
Previous work led to the proposal that the precision feeding of a high-concentrate diet may represent a potential method with which to enhance feed efficiency (FE) when rearing dairy heifers. However, the physiological and metabolic mechanisms underlying this approach remain unclear. This study used metabolomics analysis to investigate the changes in plasma metabolites of heifers precision-fed diets containing a wide range of forage to concentrate ratios. Twenty-four half-sib Holstein heifers, with a similar body condition, were randomly assigned into four groups and precision fed with diets containing different proportions of concentrate (20%, 40%, 60% and 80% based on DM). After 28 days of feeding, blood samples were collected 6 h after morning feeding and gas chromatography time-of-ﬂight/MS was used to analyze the plasma samples. Parameters of oxidative status were also determined in the plasma. The FE (after being corrected for gut fill) increased linearly (P < 0.01) with increasing level of dietary concentrate. Significant changes were identified for 38 different metabolites in the plasma of heifers fed different dietary forage to concentrate ratios. The main pathways showing alterations were clustered into those relating to carbohydrate and amino acid metabolism; all of which have been previously associated with FE changes in ruminants. Heifers fed with a high-concentrate diet had higher (P < 0.01) plasma total antioxidant capacity and superoxide dismutase but lower (P ≤ 0.02) hydroxyl radical and hydrogen peroxide than heifers fed with a low-concentrate diet, which might indicate a lower plasma oxidative status in the heifers fed a high-concentrate diet. Thus, heifers fed with a high-concentrate diet had higher FE and antioxidant capacity but a lower plasma oxidative status as well as changed carbohydrate and amino acid metabolism. Our findings provide a better understanding of how forage to concentrate ratios affect FE and metabolism in the precision-fed growing heifers.
In this paper, the generation of relativistic electron mirrors (REM) and the reflection of an ultra-short laser off the mirrors are discussed, applying two-dimension particle-in-cell simulations. REMs with ultra-high acceleration and expanding velocity can be produced from a solid nanofoil illuminated normally by an ultra-intense femtosecond laser pulse with a sharp rising edge. Chirped attosecond pulse can be produced through the reflection of a counter-propagating probe laser off the accelerating REM. In the electron moving frame, the plasma frequency of the REM keeps decreasing due to its rapid expansion. The laser frequency, on the contrary, keeps increasing due to the acceleration of REM and the relativistic Doppler shift from the lab frame to the electron moving frame. Within an ultra-short time interval, the two frequencies will be equal in the electron moving frame, which leads to the resonance between laser and REM. The reflected radiation near this interval and corresponding spectra will be amplified due to the resonance. Through adjusting the arriving time of the probe laser, a certain part of the reflected field could be selectively amplified or depressed, leading to the selective adjustment of the corresponding spectra.
A 2-year fertilization experiment was conducted to study the effect of different ratios of organic (pig) manure on wheat yield and nitrogen use efficiency (NUE). The four treatments were no nitrogen (N) (CK); 100% chemical fertilizer N (urea; T1); 70% chemical fertilizer N + 30% organic manure N (T2) and 50% chemical fertilizer N + 50% organic manure N (T3), with the same amount of applied nitrogen (120 kg/ha). The results showed the maximum grain yield (3049 kg/ha), crop nitrogen uptake (216 kg/ha), NUE (65.4%) and accumulated nitrate nitrogen (NO3−-N in 0–200 cm, 142 kg/ha) were observed in the T1 among all treatments in the first year. However, the largest grain yield (5074 kg/ha), crop nitrogen uptake (244 kg/ha) and NUE (82.5%) were under T2 treatment in the second year. Furthermore, T2 had the maximum NO3−-N content in 0–100 cm layer (116 kg/ha), especially 0–40 cm layer, and the lowest NO3−-N content in 100–200 cm (58.8 kg/ha). However, 50% organic manure N in T3 increased apparent nitrogen loss by 39.0% compared to that in T2. Therefore, 30% organic manure N application was more conducive for enhancing wheat yield and NUE and promoting environmental safety after 1-year fertilization time.
The aim of this study was to examine whether the presence of risk alleles of the norepinephrine transporter gene (SLC6A2) polymorphisms is associated with differences in regional cerebral blood flow (rCBF) measured by 99mTc-HMPAO single photon emission computerized tomography in a Korean sample of ADHD.
The present study included 24 children with ADHD (9.5±2.4 years), consisting of 20 boys and 4 girls, aged 6-16 years. We investigated the G1287A and -3081(A/T) polymorphisms of the SLC6A2. The rCBF was compared between the ADHD subjects with and without risk alleles at the G1287A polymorphism and at the -3081(A/T) polymorphism. Image analyses were performed with voxelwise t-statistics using SPM2.
1) The ADHD subjects with the A allele (risk allele) at the G1287A polymorphism showed reduced perfusion in the left middle frontal gyrus, left inferior parietal lobule, precuneus, right superior frontal gyrus, and right superior parietal lobule as compared with ADHD subjects without the A allele (p< 0.001).
2) The ADHD subjects with the A allele at the G1287A polymorphism showed increased perfusion in the right middle frontal gyrus, right middle temporal gyrus, right superior temporal gyrus, right fusiform gyrus, right precentral gyrus, and right anterior lobe of cerebellum as compared with ADHD subjects without the A allele (p< 0.001).
3) No significant perfusion differences were found between ADHD subjects with and without the T allele (risk allele) at the -3081(A/T) polymorphism.
Our findings suggest that the SLC6A2 G1287A polymorphism might exert differential effects on rCBF in children with ADHD.
The purpose of this study was to investigated the prevalence child depression in primary schools.
3685 students from Grade 3 to Grade 5 were selected from 7 primary schools of Pudong district in Shanghai by random and cluster sampling. The study design consisted of a screening stage in which the Center for Epidemiological Studies Depression Scale for Children(CES-DC) were used, and a clinical interview stage in which the K-SADS-present state version (K-SADS) and DSM-IV were used. The diagnoses of depressive disorder were made according the DSM-IV criteria.
The prevalence of children depression was 1.60% (95%CI = 1.19%∼2.00%). The prevalence rate of male(2.08%) was significant higher than that of female (1.09%)(X2=5.40, P = 0.02). The rate of depressive disorder increased with age from 0.57% (8 years old) to 2.47% (12 years old). The prevalence of depression was no significant difference between ages from 8 to 12 years old (X2 = 4.49, P = 0.34).
The prevalence rate of children depression in Shanghai is low. The prevalence of depression among boys is much higher than that of girls.It shows the prevalence of depression is no significant difference between ages from 8 to 12 years old.
Many family characteristics were reported to increase the risk of bipolar disorder (BPD). The development of BPD may be mediated through different pathways, involving diverse risk factor profiles. We evaluated the associations of family characteristics to build influential causal-pie models to estimate their contributions on the risk of developing BPD at the population level. We recruited 329 clinically diagnosed BPD patients and 202 healthy controls to collect information in parental psychopathology, parent-child relationship, and conflict within family. Other than logistic regression models, we applied causal-pie models to identify pathways involved with different family factors for BPD. The risk of BPD was significantly increased with parental depression, neurosis, anxiety, paternal substance use problems, and poor relationship with parents. Having a depressed mother further predicted early onset of BPD. Additionally, a greater risk for BPD was observed with higher numbers of paternal/maternal psychopathologies. Three significant risk profiles were identified for BPD, including paternal substance use problems (73.0%), maternal depression (17.6%), and through poor relationship with parents and conflict within the family (6.3%). Our findings demonstrate that different aspects of family characteristics elicit negative impacts on bipolar illness, which can be utilized to target specific factors to design and employ efficient intervention programs.
Menopausal syndrome has been reported to be a worldwide women's mental health problem. Aborigines in rural areas have poorer access to mental health services. Thus, it is important to evaluate such symptoms of female aborigines with different menopausal statuses and their association with depression.
The aim of the study is to evaluate the association between physiological menopausal symptoms and depression during different menopausal period among female Taiwanese aborigines.
A total of 672 Taiwanese aboriginal women, aged 40–60, were recruited in the interviewing study and classified as pre-, peri-, and postmenopausal according to menstrual bleeding patterns in the previous 12 months. Then, the postmenopausal symptoms, depression, self-perceived health, family support, and associated demographic variables were assessed by questionnaire based on the results of interviewing by research assistants.
The results revealed that perimenopausal statuses were associated with depression and women with a perimenopausal status had a higher prevalence of depression than those with a premenopausal status. A higher score on physiological postmenopausal symptoms was found to be significantly associated with depression. Furthermore, somatic symptoms were associated with depression for pre-, peri-, and postmenopausal statuses. Moreover, sexual dysfunction and vasomotor symptoms were associated with depression only in the premenopausal status and postmenopausal status, respectively.
Depression should be routinely evaluated for female Taiwanese aborigines consulting with physicians for menopause symptoms, especially for somatic symptoms. Furthermore, attention should be provided to premenopausal women with sexual dysfunction and postmenopausal women with vasomotor symptoms for depression.
Post-stroke depression (PSD) is the most common psychiatric complication facing stroke survivors and has been associated with increased distress, physical disability, poor rehabilitation, and suicidal ideation. However, the pathophysiological mechanisms underlying PSD remain unknown, and no objective laboratory-based test is available to aid PSD diagnosis or monitor progression.
Here, an isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomic approach was performed to identify differentially expressed proteins in plasma samples obtained from PSD, stroke, and healthy control subjects.
The significantly differentiated proteins were primarily involved in lipid metabolism and immunoregulation. Six proteins associated with these processes – apolipoprotein A-IV (ApoA-IV), apolipoprotein C-II (ApoC-II), C-reactive protein (CRP), gelsolin, haptoglobin, and leucine-rich alpha-2-glycoprotein (LRG) – were selected for Western blotting validation. ApoA-IV expression was significantly upregulated in PSD as compared to stroke subjects. ApoC-II, LRG, and CRP expression were significantly downregulated in both PSD and HC subjects relative to stroke subjects. Gelsolin and haptoglobin expression were significantly dysregulated across all three groups with the following expression profiles: gelsolin, healthy control > PSD > stroke subjects; haptoglobin, stroke > PSD > healthy control.
Early perturbation of lipid metabolism and immunoregulation may be involved in the pathophysiology of PSD. The combination of increased gelsolin levels accompanied by decreased haptoglobin levels shows promise as a plasma-based diagnostic biomarker panel for detecting increased PSD risk in post-stroke patients.
Alcohol consumption is a part of the aboriginal culture. It was found that is a predominant health problem in aboriginal community. There was little research describing whether gender differences in harmful drinking and adverse drinking consequence among aborigines. Thus, it is important to evaluate such differences in order to provide evidence for developing interventions in problem drinking.
The aim of the study is to examine the gender differences in the prevalence, correlates, and adverse drinking consequences among harmful alcohol users in Taiwanese aborigines.
A cross-sectional survey was conducted. 449 study participants, aged 18-60, were recruited into the study from community-dwelling aborigines in southern Taiwan. Alcohol Use Disorders Identification Test (AUDIT) was used to collect information regarding harmful alcohol drinking. Personal characteristics, related risk factors and adverse drinking consequences were assessed by questionnaire.
The result revealed that the prevalence of harmful drinking in male users was 71.6%, female users were 49.2%. The results showed that female harmful alcohol users were more likely to have poor mental health, 58% of them with suicidal ideation, 50% with depression, more inactive in religious practice, and unemployed. It was also found that more than half of the male harmful alcohol users have adverse drinking consequence, including accidental injury, quarreled with others, and unable to work.
Harmful drinking was a predominant health problem in aborigines. This finding suggested that depression and suicidal ideation should be routinely evaluated for female harmful alcohol users by the professional of primary care.
It is known that Sexual Dysfunction (SD) is higher in patient with depression than in the general population. Though antidepressant seems to worsen the situation, there are also indications that the gender may play a role on it.
Evaluate the gender effect of sexual function among unmedicated MDD, MDD receiving antidepressant, and healthy controls.
The sample was formed by male and female Taiwanese outpatients in three age and sex matched groups, with sixty nine participants per group: unmedicated MDD, MDD receiving antidepressant, and healthy controls. the diagnoses of depressions were performed according DSM-IV and Taiwanese Depression Questionnaire. SD was evaluated with the Chinese version of the Changes in Sexual Functioning Questionnaire. Finally, the data was analyzed using SPSS software v17. Mixed designed ANOVA was used.
There are significant differences between males and females CSFQ results (sex main effect F = 82.44, p < 0.001) and between groups (group main effect F = 3.48, p = 0.034). Additionally, the 2-way interaction between sex and group was also significant (F = 3.40, p = 0.036). Simple main effect analysis shows differences among male participants, between healthy and medicated males (F = 11.41, p = 0.002), but not in female (F = 1.58, p = 0.21). However the statistics weren’t different between females groups, the medicated expresses better results (similar to healthy group) than the unmedicated one.
SD is different between genders in each of the groups. Antidepressant seems to increase SD in man, while improves sexual satisfaction/function among depressive woman. We speculate that psychological improvement after treatment may have different impact between genders on sexual satisfaction.
The presence of comorbid anxiety disorders (AD) and bipolar II disorders (BP-II) compounds disability complicates treatment, worsens prognosis, and has been understudied. The genes involved in metabolizing dopamine and encoding dopamine receptors, such as aldehyde dehydrogenase 2 (ALDH2) and dopamine D2 receptor (DRD2) genes, may be important to the pathogenesis of BP-II comorbid with AD. We aimed to clarify ALDH2 and DRD2 genes for predisposition to BP-II comorbid with and without AD. The sample consisted of 335 subjects BP-II without AD, 127 subjects BP-II with AD and 348 healthy subjects as normal control. The genotypes of the ALDH2 and DRD2 Taq-IA polymorphisms were determined using polymerase chain reactions plus restriction fragment length polymorphism analysis. Logistic regression analysis showed a statistically significant association between DRD2 Taq-I A1/A2 genotype and BP-II with AD (OR = 2.231, P = 0.021). Moreover, a significant interaction of the DRD2 Taq-I A1/A1 and the ALDH2*1*1 genotypes in BP-II without AD was revealed (OR = 5.623, P = 0.001) compared with normal control. Our findings support the hypothesis that a unique genetic distinction between BP-II with and without AD, and suggest a novel association between DRD2 Taq-I A1/A2 genotype and BP-II with AD. Our study also provides further evidence that the ALDH2 and DRD2 genes interact in BP-II, particularly BP-II without AD.
Recently, a triple-network model suggested the abnormal interactions between the executive-control network (ECN), default-mode network (DMN) and salience network (SN) are important characteristics of addiction, in which the SN plays a critical role in allocating attentional resources toward the ECN and DMN. Although increasing studies have reported dysfunctions in these brain networks in Internet gaming disorder (IGD), interactions between these networks, particularly in the context of the triple-network model, have not been investigated in IGD. Thus, we aimed to assess alterations in the inter-network interactions of these large-scale networks in IGD, and to associate the alterations with IGD-related behaviors.
DMN, ECN and SN were identified using group-level independent component analysis (gICA) in 39 individuals with IGD and 34 age and gender matched healthy controls (HCs). Then alterations in the SN-ECN and SN-DMN connectivity, as well as in the modulation of ECN versus DMN by SN, using a resource allocation index (RAI) developed and validated previously in nicotine addiction, were assessed. Further, associations between these altered network coupling and clinical assessments were also examined.
Compared with HCs, IGD had significantly increased SN-DMN connectivity and decreased RAI in right hemisphere (rRAI), and the rRAI in IGD was negatively associated with their scores of craving.
These findings suggest that the deficient modulation of ECN versus DMN by SN might provide a mechanistic framework to better understand the neural basis of IGD and might provide novel evidence for the triple-network model in IGD.
This research examined gender variations in depressive mood for high school students affected by emotional upset and how such depressive mood affect their sleep quality.
Research was conducted from September 2015 to October 2015. Both males and females were divided into normal group and depressive group by Zung Self-rating Depression Scale (ZSDS). Each group adopted the Pittsburgh Sleep Quality Index (PSQI) to measure sleep quality.
Analysis was made on a total of 155 students, which were 83 male students and 72 female. The average ZSDS for all high school students was 43.38 and the average PSQI was 5.39. The number of male students in the normal and depressive group who were diagnosed with sleep disorder were 2 (3.8%) and 9 (29.0%), respectively (P < 0.05). But the number of female students in the normal and depressive group who were diagnosed with sleep disorder were 11 (32.4%) and 33 (86.8%), respectively (P < 0.05). Both males and females shared a meaningful result over sleep latency, sleep disturbance, use of sleep medication, and daytime functional disturbance among 7 items of PSQI for sleep quality, and female students had a significantly meaningful result over sleep duration, habitual sleep effects (P < 0.05).
This research showed that sleep quality of all high school students was not too bad but it can be problematic for those with depressive mood. Especially, female students were diagnosed with sleep disorder more than male students.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Childhoods in urban or rural environments may differentially affect risk for neuropsychiatric disorders. Here, we leveraged on dramatic urbanization and rural-urban migration since the 1980s in China to explore the hypothesis that rural or urban childhoods may differentially influence memory processing and neural responses to neutral and aversive stimuli.
Explore the underlying mechanisms of childhood environment effect on brain function and neuropsychiatric risk.
We examined 420 adult subjects with similar current socioeconomic status and living in Beijing, China, but with differing rural (n = 227) or urban (n = 193) childhoods. In an episodic memory paradigm scanned in a 3 T GE MRI, subjects viewed blocks of neutral or aversive pictures in the encoding and retrieval sessions.
Episodic memory accuracy for neutral stimuli was less than for aversive stimuli (P < 0.001). However, subjects with rural childhoods apparently performed less accurately for memory of aversive but not neutral stimuli (P < 0.01). In subjects with rural childhoods, there was relatively increased engagement of bilateral striatum at encoding, increased engagement of bilateral hippocampus at retrieval of neutral and aversive stimuli, and increased engagement of amygdala at aversive retrieval (P < 0.05 FDR corrected, cluster size > 50).
Rural or urban childhoods appear associated with physiological and behavioural differences, particularly in the neural processing of aversive episodic memory at medial temporal and striatal brain regions. It remains to be explored the extent to which these effects relate to individual risk for neuropsychiatric or stress-related disorders.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
This study aimed at comparing the factors associated with the natural progression between typical progressors (TPs) and rapid progressors (RPs) in HIV-infected individuals. A retrospective study was conducted on 2095 eligible HIV-infected individuals from 1995 to 2016 in a high-risk area of Henan Province, China. Propensity score matching was used to balance covariates, and the conditional logistic regression analyses were performed to explore the factors of natural disease progression among HIV infectors. A total of 379 pairs of RPs and TPs were matched. The standardised difference values of all covariates were less than 10%. HIV-infected individuals transmitted through sexual transmission (odds ratio (OR) 0.56, 95% confidence interval (CI) 0.36–0.85) were more likely to progress to AIDS compared with those infected through contaminated blood. Older age at diagnosis of HIV-infected individuals (OR 0.72, 95% CI 0.58–0.89) exhibited a faster progression to AIDS. HIV-infected individuals identified through a unique survey (OR 7.01, 95% CI 2.99–16.44) were less likely to progress to AIDS compared with those identified through medical institutions. HIV-infected individuals who had higher baseline CD4+T cell counts (OR 3.37, 95% CI 2.59–4.38) had a slower progression to AIDS. These findings provide evidence for natural disease progression from HIV to AIDS between TPs and RPs.
In order to map quantitative trait loci (QTLs) for allometries of body compositions and metabolic traits in chicken, we phenotypically characterize the allometric growths of multiple body components and metabolic traits relative to BWs using joint allometric scaling models and then establish random regression models (RRMs) to fit genetic effects of markers and minor polygenes derived from the pedigree on the allometric scalings. Prior to statistically inferring the QTLs for the allometric scalings by solving the RRMs, the LASSO technique is adopted to rapidly shrink most of marker genetic effects to zero. Computer simulation analysis confirms the reliability and adaptability of the so-called LASSO-RRM mapping method. In the F2 population constructed by multiple families, we formulate two joint allometric scaling models of body compositions and metabolic traits, in which six of nine body compositions are tested as significant, while six of eight metabolic traits are as significant. For body compositions, a total of 14 QTLs, of which 9 dominant, were detected to be associated with the allometric scalings of drumstick, fat, heart, shank, liver and spleen to BWs; while for metabolic traits, a total of 19 QTLs also including 9 dominant be responsible for the allometries of T4, IGFI, IGFII, GLC, INS, IGR to BWs. The detectable QTLs or highly linked markers can be used to regulate relative growths of the body components and metabolic traits to BWs in marker-assisted breeding of chickens.
Ultraintense laser-driven relativistic electrons provide a way of heating matter to high energy density states related to many applications. However, the transport of relativistic electrons in solid targets has not been understood well yet, especially in dielectric targets. We present the first detailed two-dimensional particle-in-cell simulations of relativistic electron transport in a silicon target by including the field ionization and collisional ionization processes. An ionization wave is found propagating in the insulator, with a velocity dependent on laser intensity and slower than the relativistic electron velocity. Widely spread electric fields in front of the sheath fields are observed due to the collective effect of free electrons and ions. The electric fields are much weaker than the threshold electric field of field ionization. Two-stream instability behind the ionization front arises for the cases with laser intensity greater than
that produce high relativistic electron current densities.
We aimed to investigate the heterogeneity of seasonal suicide patterns among multiple geographically, demographically and socioeconomically diverse populations.
Weekly time-series data of suicide counts for 354 communities in 12 countries during 1986–2016 were analysed. Two-stage analysis was performed. In the first stage, a generalised linear model, including cyclic splines, was used to estimate seasonal patterns of suicide for each community. In the second stage, the community-specific seasonal patterns were combined for each country using meta-regression. In addition, the community-specific seasonal patterns were regressed onto community-level socioeconomic, demographic and environmental indicators using meta-regression.
We observed seasonal patterns in suicide, with the counts peaking in spring and declining to a trough in winter in most of the countries. However, the shape of seasonal patterns varied among countries from bimodal to unimodal seasonality. The amplitude of seasonal patterns (i.e. the peak/trough relative risk) also varied from 1.47 (95% confidence interval [CI]: 1.33–1.62) to 1.05 (95% CI: 1.01–1.1) among 12 countries. The subgroup difference in the seasonal pattern also varied over countries. In some countries, larger amplitude was shown for females and for the elderly population (≥65 years of age) than for males and for younger people, respectively. The subperiod difference also varied; some countries showed increasing seasonality while others showed a decrease or little change. Finally, the amplitude was larger for communities with colder climates, higher proportions of elderly people and lower unemployment rates (p-values < 0.05).
Despite the common features of a spring peak and a winter trough, seasonal suicide patterns were largely heterogeneous in shape, amplitude, subgroup differences and temporal changes among different populations, as influenced by climate, demographic and socioeconomic conditions. Our findings may help elucidate the underlying mechanisms of seasonal suicide patterns and aid in improving the design of population-specific suicide prevention programmes based on these patterns.