Displaying publications 1 - 20 of 410 in total

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  1. Chen L, Xu YY, Lin JY, Ji ZP, Yang F, Tan S, et al.
    Asian J Psychiatr, 2024 Mar;93:103958.
    PMID: 38364597 DOI: 10.1016/j.ajp.2024.103958
    BACKGROUND AND AIM: Suicide is nearly always associated with underlying mental disorders. Risk factors for suicide attempts (SAs) in patients with bipolar disorder (BD) misdiagnosed with major depressive disorder (MDD) remain unelucidated. This study was to evaluate the prevalence and clinical risk factors of SAs in Chinese patients with BD misdiagnosed with MDD.

    METHODS: A total of 1487 patients with MDD from 13 mental health institutions in China were enrolled. Mini International Neuropsychiatric Interview (MINI) was used to identify patients with BD who are misdiagnosed as MDD. The general sociodemographic and clinical data of the patients were collected and MINI suicide module was used to identify patients with SAs in these misdiagnosed patients.

    RESULTS: In China, 20.6% of patients with BD were incorrectly diagnosed as having MDD. Among these misdiagnosed patients, 26.5% had attempted suicide. These patients tended to be older, had a higher number of hospitalizations, and were more likely to experience frequent and seasonal depressive episodes with atypical features, psychotic symptoms, and suicidal thoughts. Frequent depressive episodes and suicidal thoughts during depression were identified as independent risk factors for SAs. Additionally, significant sociodemographic and clinical differences were found between individuals misdiagnosed with MDD in BD and patients with MDD who have attempted suicide.

    CONCLUSIONS: This study highlights the importance of accurate diagnosis in individuals with BD and provide valuable insights for the targeted identification and intervention of individuals with BD misdiagnosed as having MDD and those with genuine MDD, particularly in relation to suicidal behavior.

  2. Hülsmann L, Chisholm RA, Comita L, Visser MD, de Souza Leite M, Aguilar S, et al.
    Nature, 2024 Mar;627(8004):564-571.
    PMID: 38418889 DOI: 10.1038/s41586-024-07118-4
    Numerous studies have shown reduced performance in plants that are surrounded by neighbours of the same species1,2, a phenomenon known as conspecific negative density dependence (CNDD)3. A long-held ecological hypothesis posits that CNDD is more pronounced in tropical than in temperate forests4,5, which increases community stabilization, species coexistence and the diversity of local tree species6,7. Previous analyses supporting such a latitudinal gradient in CNDD8,9 have suffered from methodological limitations related to the use of static data10-12. Here we present a comprehensive assessment of latitudinal CNDD patterns using dynamic mortality data to estimate species-site-specific CNDD across 23 sites. Averaged across species, we found that stabilizing CNDD was present at all except one site, but that average stabilizing CNDD was not stronger toward the tropics. However, in tropical tree communities, rare and intermediate abundant species experienced stronger stabilizing CNDD than did common species. This pattern was absent in temperate forests, which suggests that CNDD influences species abundances more strongly in tropical forests than it does in temperate ones13. We also found that interspecific variation in CNDD, which might attenuate its stabilizing effect on species diversity14,15, was high but not significantly different across latitudes. Although the consequences of these patterns for latitudinal diversity gradients are difficult to evaluate, we speculate that a more effective regulation of population abundances could translate into greater stabilization of tropical tree communities and thus contribute to the high local diversity of tropical forests.
  3. Medina-Vega JA, Zuleta D, Aguilar S, Alonso A, Bissiengou P, Brockelman WY, et al.
    Nat Ecol Evol, 2024 Jan 10.
    PMID: 38200369 DOI: 10.1038/s41559-023-02298-0
    Mycorrhizae, a form of plant-fungal symbioses, mediate vegetation impacts on ecosystem functioning. Climatic effects on decomposition and soil quality are suggested to drive mycorrhizal distributions, with arbuscular mycorrhizal plants prevailing in low-latitude/high-soil-quality areas and ectomycorrhizal (EcM) plants in high-latitude/low-soil-quality areas. However, these generalizations, based on coarse-resolution data, obscure finer-scale variations and result in high uncertainties in the predicted distributions of mycorrhizal types and their drivers. Using data from 31 lowland tropical forests, both at a coarse scale (mean-plot-level data) and fine scale (20 × 20 metres from a subset of 16 sites), we demonstrate that the distribution and abundance of EcM-associated trees are independent of soil quality. Resource exchange differences among mycorrhizal partners, stemming from diverse evolutionary origins of mycorrhizal fungi, may decouple soil fertility from the advantage provided by mycorrhizal associations. Additionally, distinct historical biogeographies and diversification patterns have led to differences in forest composition and nutrient-acquisition strategies across three major tropical regions. Notably, Africa and Asia's lowland tropical forests have abundant EcM trees, whereas they are relatively scarce in lowland neotropical forests. A greater understanding of the functional biology of mycorrhizal symbiosis is required, especially in the lowland tropics, to overcome biases from assuming similarity to temperate and boreal regions.
  4. Baharin SNAN, Tan SL, Sam IC, Chan YF
    Trop Biomed, 2023 Dec 01;40(4):478-485.
    PMID: 38308836 DOI: 10.47665/tb.40.4.014
    Hand, foot, and mouth disease (HFMD) is a contagious childhood disease caused by enteroviruses including enterovirus A71 (EV-A71), coxsackievirus A6 (CV-A6) and CV-A16 transmitted via direct and indirect contact. Different types of toy surfaces can affect the stability of viruses. Understanding the stability of enteroviruses on toys provides insightful data for effective disinfection in kindergartens or homes. Porous (ethylene-vinyl acetate mat foam, paper, pinewood, polyester fabric, and squishy polyurethane foam) and non-porous (acrylonitrile butadiene styrene plastic and stainless-steel coin) surfaces were inoculated with EV-A71 at 4, 24, and 35°C, and coxsackieviruses at 24°C. Infectious enteroviruses were recovered and titred in median tissue culture infectious dose assay (TCID50). Atomic force microscopy (AFM) images were taken from surfaces to examine association of surface roughness with virus stability. Overall, infectious enteroviruses were persistent on all non-porous and porous surfaces. Virus persistence was longest at 4°C followed by 24°C and 35°C. EV-A71 half-lives ranged between 6.4-12.8 hours at 4°C, 2.4-6.7 hours at 24°C, and 0.13-2.7 hours at 35°C. At lower virus titres exposed to 24°C, half-lives of enteroviruses ranged from 0.1-1.4 hours. Surface roughness values from AFM suggested smooth surfaces of non-porous surfaces were associated with better virus stability. Temperature, enterovirus concentration, and type of surface affected persistence and stability of enteroviruses. Our findings suggest both porous and non-porous surfaces in kindergartens allow enterovirus persistence and should be frequently disinfected to curb HFMD outbreaks in kindergartens.
  5. Tan S, Ismail MAB, Daud TIM, Hod R, Ahmad N
    Indian J Psychiatry, 2023 Sep;65(9):934-940.
    PMID: 37841542 DOI: 10.4103/indianjpsychiatry.indianjpsychiatry_240_23
    INTRODUCTION: Despite the increasing number of mental health professionals in Malaysia, many have yet to receive adequate treatment for common mental illnesses such as depression and anxiety. Coupled with the increasing number of mobile phone users globally, smartphone-based intervention can be a promising mental health intervention. Thus, this study aims to investigate the efficacy of using a smartphone-based mental health application in addition to treatment-as-usual (TAU) in outpatients with depressive and/or anxiety symptoms.

    METHODS: Psychiatric outpatients that fulfill the selection criteria were recruited and randomized into two groups, the intervention group (n = 24) and the control group (n = 24). Those in the intervention group received MoodMission in addition to TAU, while those in the control group received TAU. Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) scores were assessed at baseline and after four weeks.

    RESULTS: A total of 48 participants were recruited, randomized, and completed the study. Baseline characteristics for both groups were comparable. There is no significant mean difference between-group comparison of PHQ-9 (1.31, 95% CI -1.35, 3.98) and GAD-7 (0.02, 95% CI -2.01, 2.05) scores at four weeks. However, for the intervention group, there was a significant improvement in the PHQ-9 score at four weeks [mean difference 2.58 (95% CI 1.16, 4.01), P = 0.001)].

    CONCLUSION: This study showed no significant improvement in anxiety symptoms after four weeks. Use of smartphone-based mental health applications led to significant reduction of depressive symptoms.

  6. Tumasyan A, Adam W, Bergauer T, Dragicevic M, Del Valle AE, Frühwirth R, et al.
    Phys Rev Lett, 2023 Aug 04;131(5):051901.
    PMID: 37595238 DOI: 10.1103/PhysRevLett.131.051901
    The structure of nucleons is multidimensional and depends on the transverse momenta, spatial geometry, and polarization of the constituent partons. Such a structure can be studied using high-energy photons produced in ultraperipheral heavy-ion collisions. The first measurement of the azimuthal angular correlations of exclusively produced events with two jets in photon-lead interactions at large momentum transfer is presented, a process that is considered to be sensitive to the underlying nuclear gluon polarization. This study uses a data sample of ultraperipheral lead-lead collisions at sqrt[s_{NN}]=5.02  TeV, corresponding to an integrated luminosity of 0.38  nb^{-1}, collected with the CMS experiment at the LHC. The measured second harmonic of the correlation between the sum and difference of the two jet transverse momentum vectors is found to be positive, and rising, as the dijet transverse momentum increases. A well-tuned model that has been successful at describing a wide range of proton scattering data from the HERA experiments fails to describe the observed correlations, suggesting the presence of gluon polarization effects.
  7. Kirkman T, Fun Tan S, Chavez-Pacheco SM, Hammer A, Abell C, Tosin M, et al.
    ChemMedChem, 2023 Aug 01;18(15):e202300240.
    PMID: 37195570 DOI: 10.1002/cmdc.202300240
    Dihydrofolate reductase (DHFR) is a key enzyme involved in the folate pathway that has been heavily targeted for the development of therapeutics against cancer and bacterial and protozoa infections amongst others. Despite being an essential enzyme for Mycobacterium tuberculosis (Mtb) viability, DHFR remains an underexploited target for tuberculosis (TB) treatment. Herein, we report the preparation and evaluation of a series of compounds against Mtb DHFR (MtbDHFR). The compounds have been designed using a merging strategy of traditional pyrimidine-based antifolates with a previously discovered unique fragment hit against MtbDHFR. In this series, four compounds displayed a high affinity against MtbDHFR, with sub-micromolar affinities. Additionally, we determined the binding mode of six of the best compounds using protein crystallography, which revealed occupation of an underutilised region of the active site.
  8. Tan ST, Shahril PIA
    Ethics Med Public Health, 2023 Apr;27:100874.
    PMID: 36776244 DOI: 10.1016/j.jemep.2023.100874
    BACKGROUND: The COVID-19 pandemic may have worsened food insecurity and altered the eating behaviour of young adults. Therefore, this cross-sectional study aims to investigate the correlation between moderate-to-severe food insecurity and the risk of eating disorders among young urbanists in Malaysia after the pandemic-led lockdown.

    METHODS: The food security status and the risk of eating disorders were assessed using the validated Food Insecurity Experience Scale (FIES) and Eating Attitude Test (EAT-26), respectively.

    RESULTS: Among the 208 young urbanists, approximately one-third (30.8%) were moderate-to-severe food insecure and about one-fifth (18.8%) were at risk of eating disorders after the nationwide lockdown. With the adjustment of gender, the binary logistic regression analysis revealed that moderate-to-severe food insecure individuals were 2.279 times (P = 0.030, 95% CI = 1.084-4.791) more likely to engage in disordered eating in the aftermath of the COVID-19 pandemic. The findings of partial correlation further indicated that moderate-to-severe food insecurity was positively correlated (rpartial = 0.156, P = 0.024) with bulimia and food preoccupation after the outbreak.

    CONCLUSIONS: Governments and non-governmental organizations must work closely to develop effective policies to address food insecurity and disordered eating behaviour among young urbanists - after the pandemic.

  9. Tan S, Zhou G, Yang Q, Ge S, Liu J, Cheng YW, et al.
    Sci Total Environ, 2023 Mar 15;864:160990.
    PMID: 36539095 DOI: 10.1016/j.scitotenv.2022.160990
    Traditional disposal of animal manures and lignocellulosic biomass is restricted by its inefficiency and sluggishness. To advance the carbon management and greenhouse gas mitigation, this review scrutinizes the effect of pyrolysis in promoting the sustainable biomass and manure disposal as well as stimulating the biochar industry development. This review has examined the advancement of pyrolysis of animal manure (AM) and lignocellulosic biomass (LB) in terms of efficiency, cost-effectiveness, and operability. In particular, the applicability of pyrolysis biochar in enhancing the crops yields via soil remediation is highlighted. Through pyrolysis, the heavy metals of animal manures are fixated in the biochar, thereby both soil contamination via leaching and heavy metal uptake by crops are minimized. Pyrolysis biochar is potentially use in soil remediation for agronomic and environmental co-benefits. Fast pyrolysis assures high bio-oil yield and revenue with better return on investment whereas slow pyrolysis has low revenue despite its minimum investment cost because of relatively low selling price of biochar. For future commercialization, both continuous reactors and catalysis can be integrated to pyrolysis to ameliorate the efficiency and economic value of pyrolysis biochar.
  10. Hoo CZ, Wan Abdullah WZ, Omar H, Tan SS
    Med J Malaysia, 2023 Mar;78(2):234-240.
    PMID: 36988536
    INTRODUCTION: Worldwide, around 296 million people have hepatitis B virus (HBV) infection, most commonly transmitted from mother-to-child. Global Health Sector Strategy on Viral Hepatitis (GHSSVH) was introduced in May 2016, calling for elimination of viral hepatitis by 2030. This study aims to compare practice in a tertiary liver centre before and after GHSSVH introduction for prevention of mother-to-child transmission (MTCT).

    MATERIALS AND METHODS: This retrospective cohort study was performed in a tertiary referral liver centre in Malaysia, using data from electronic medical record from January 2015 to December 2019. A total of 1457 medical records of female with HBV infection were screened. The inclusion criteria of the study were pregnant women with HBsAg positive or known to have HBV infection during the study period. We excluded patients with co-infections of other types of viral hepatitis or human immunodeficiency virus, concurrent liver diseases (e.g.: autoimmune hepatitis, Wilson’s disease), previous organ transplant and malignancy—except for hepatocellular carcinoma (HCC).

    RESULTS: This study included 117 pregnancies and 21/117 (17.9%) were on antiviral therapy (AVT) for HBV. In 2017– 2019, 13/18 (72.2%) of those with HBV DNA >200,000IU/ml were on AVT, compared to 5/9 (55.6%) for 2015–2016, indicating 58% (95% CI −63% to 568%) higher odds of being on AVT in post GHSSVH group after accounting for HBV DNA.

    CONCLUSION: Uptake of maternal AVT for the prevention of MTCT shows an increased trend since the introduction of GHSSVH, with room for improvement.

  11. David NCE, Juliana H, Chok M, Gan YZ, Tan YC, Nur Adlina MN, et al.
    Med J Malaysia, 2023 Jan;78(1):80-86.
    PMID: 36715196
    INTRODUCTION: The COVID-19 pandemic has reached a phase where many have been infected at least once. Healthcare workers were not spared from being infected. This study aimed to determine the period prevalence of COVID-19 among the paediatric healthcare workers in Negeri Sembilan as the country transitioned into an endemic phase of the pandemic. Additionally, we investigate potential sociodemographic and occupational characteristics associated with SARS-CoV-2 infection among healthcare workers.

    MATERIALS AND METHODS: A cross-sectional study was conducted among the healthcare workers in the paediatric department at three public specialist hospitals in Negeri Sembilan between 15 and 21 April 2022. Data were collected through a self-administered questionnaire.

    RESULTS: Out of the 504 eligible healthcare workers, 493 participated in this study (response rate 97.8%). The overall prevalence of COVID-19 (11 March 2020-15 April 2022) among healthcare workers was 50.9%. The majority (80.1%) were infected during the Omicron wave two months before the survey. Household contacts accounted for 35.9% of infection sources. The proportion of non-doctors in the COVID-19-infected group was significantly higher compared to the non-infected group (74.1% vs 64.0%, p=0.016). The COVID-19-infected group had a higher proportion of schoolgoing children (44.6% vs 30.6%, p=0.001) and children who attended pre-school/sent to the babysitter (49.0% vs 24.4%, p<0.001). There were no significant differences between infection rates among the healthcare workers working in the tertiary hospital and the district hospitals. There were also no significant differences in the proportion of COVID-19- infected doctors and nurses when analysed by seniority.

    CONCLUSION: Our study provided an estimate on the prevalence of COVID-19 among paediatric healthcare workers in Negeri Sembilan and the factors associated with infection, which captures the extent and magnitude of this pandemic on the state's paediatric department. Most infections resulted from household contact, with a higher proportion of infected healthcare workers having young children.

  12. Tan SG, Xu PY
    Trop Biomed, 2022 Dec 01;39(4):524-530.
    PMID: 36602211 DOI: 10.47665/tb.39.4.007
    Canine babesiosis caused by Babesia spp. is a noteworthy tick-borne zoonotic disease of domestic dogs and wild canids. In present study, a total of 556 blood samples were randomly collected from pet dogs in eight cities of Hunan province, subtropical China. Genomic DNA was extracted and Babesia DNA was detected by amplification of partial 18S rRNA gene sequences. A total of 56 (10.1%) blood samples were tested positive for Babesia species. Sequence analysis showed that 29 dogs (5.2%) were positive for B. gibsoni, and other 27 dogs for B. vogeli (4.9%). The age and health status were considered as important risk factors for B. gibsoni and B. vogeli infections in pet dogs in this study (P<0.05). Phylogenetic analysis showed that the examined positive samples were highly clustered in the same branch with B. gibsoni and B. vogeli, respectively. This is the first molecular report of B. gibsoni infection in pet dogs in Hunan province, subtropical China. Our finding has provided a guide for the control of dog babesiosis in China and elsewhere.
  13. Okuno S, Yin T, Nanami S, Matsuyama S, Kamiya K, Tan S, et al.
    Ecol Evol, 2022 Nov;12(11):e9536.
    PMID: 36440315 DOI: 10.1002/ece3.9536
    Community phylogenetic analysis is an effective approach to understanding the process of community formation. The phylogenetic tree of the species pool is reconstructed in the first step, and the phylogenetic tree obtained in the second step is used to analyze phylogenetic diversity. Sythetic trees have often been used in the construction of phylogenentic trees; however, in tropical rainforests with many closely related species, synthetic trees contain many unresolved nodes, which may affect the results of phylogenetic structure analysis. Here, we constructed a phylogenetic tree using DNA barcode sequences (rbcL, matK, trnH-psbA) for 737 tree species from the rainforests of Borneo, which have a high-species diversity and many closely related species. The phylogenetic tree had fewer polytomies and more branch length variations than the Phylocom synthetic trees. Comparison of community phylogenetic analyses indicated that values of the standardized effect size of mean pairwise distance (SES-MPD) were highly correlated between Phylocom and DNA barcode trees, but less so for the standardized effect size of mean nearest taxon distance (SES-MNTD), suggesting that caution is needed when using synthetic trees for communities containing many congeneric species, especially when using SES-MNTD. Simulation analysis suggested that spatial dependence on phylogenetic diversity is related to the phylogenetic signal of the species' habitat niche and the spatial structure of habitat, indicating the importance of detailed phylogeny in understanding community assembly processes.
  14. Wilfred G, Ong TC, Sh Shahnaz SAK, Wah HK, Carlo ES, Jameela S, et al.
    Blood Cell Ther, 2022 May 25;5(2):45-53.
    PMID: 36710947 DOI: 10.31547/bct-2021-018
    BACKGROUND: Hematopoietic stem cell transplantation (HSCT) provides curative therapy in almost 90% of patients with severe aplastic anemia (SAA). Older age, long duration of disease with consequent heavy exposure to transfusion, and active infection at the time of HSCT have a negative influence on the outcomes, causing graft failure (GF) and graft versus host disease (GVHD).

    PURPOSE: To describe the outcomes of all patients with SAA who received hematopoietic stem cell transplantation at a tertiary center in Malaysia.

    MATERIALS AND METHODS: We included a 20 y cohort of patients who underwent transplantation from January 1, 1999 to December 31, 2019. Data were obtained from electronic medical records. Demographics, clinical characteristics, and treatment outcomes were analyzed using descriptive statistics. Overall survival (OS) was analyzed using Kaplan-Meier curves. All analyses were conducted using the Statistical Package for the Social Sciences (SPSS) version 25.

    RESULTS: Eighty patients were analyzed. The median age at diagnosis was 19 years, and 59% patients were male (n = 47). Malay ethnicity was the highest (52.5%), followed by Chinese (20.0%) and Native Sabah (15.0%). The median duration from diagnosis to transplantation was 13.5 weeks. A majority of patients received Cy-ATG conditioning (n = 51, 63.8%). Forty-one patients (51.2%) used peripheral blood as stem cell source, 36 patients (45.0%) used granulocyte colony stimulating factor (G-CSF) primed marrow graft and 3 patients (3.8%) used both. The mean nucleated mononuclear cell and CD34 cell doses were 4.7 ± 1.7 × 108/kg and 4.6 ± 1.9 × 106/kg, respectively. Median engraftment for WBCs and platelets was 14 and 15 days, respectively. There was no difference in WBC and platelet engraftment in patients who received peripheral blood stem cell transplantation or bone marrow transplant. At a median follow-up of 54 months, 49 patients (61.3%) achieved complete remission and 8 patients (10.0%) achieved partial remission. The estimated 5 y OS was 63% and higher among those who received HSCT within 3 months of diagnosis. Twenty-two patients (27.5%) died within 100 d of transplantation, and a majority of these died due to pre-engraftment death.

    DISCUSSION AND CONCLUSIONS: Our study found that patients who received early allogeneic transplantation for SAA had better outcomes. Pre-engraftment failure was the major cause of transplant-related mortality within 100 d. Further studies are required to identify the factors responsible for delaying transplantation to improve treatment outcomes.

  15. Needham JF, Johnson DJ, Anderson-Teixeira KJ, Bourg N, Bunyavejchewin S, Butt N, et al.
    Glob Chang Biol, 2022 Jan 25.
    PMID: 35080088 DOI: 10.1111/gcb.16100
    The growth and survival of individual trees determine the physical structure of a forest with important consequences for forest function. However, given the diversity of tree species and forest biomes, quantifying the multitude of demographic strategies within and across forests and the way that they translate into forest structure and function remains a significant challenge. Here, we quantify the demographic rates of 1,961 tree species from temperate and tropical forests and evaluate how demographic diversity (DD) and demographic composition (DC) differ across forests, and how these differences in demography relate to species richness, aboveground biomass, and carbon residence time. We find wide variation in DD and DC across forest plots, patterns that are not explained by species richness or climate variables alone. There is no evidence that DD has an effect on either aboveground biomass or carbon residence time. Rather, the DC of forests, specifically the relative abundance of large statured species, predicted both biomass and carbon residence time. Our results demonstrate the distinct demographic compositions of globally distributed forests, reflecting biogeography, recent history, and current plot conditions. Linking the demographic composition of forests to resilience or vulnerability to climate change, will improve the precision and accuracy of predictions of future forest composition, structure and function.
  16. Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, et al.
    Phys Rev Lett, 2022 Jan 21;128(3):032001.
    PMID: 35119878 DOI: 10.1103/PhysRevLett.128.032001
    The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) production is studied in lead-lead (Pb-Pb) collisions at a center-of-mass energy of sqrt[s_{NN}]=5.02  TeV per nucleon pair, using the decay chain X(3872)→J/ψπ^{+}π^{-}→μ^{+}μ^{-}π^{+}π^{-}. The data were recorded with the CMS detector in 2018 and correspond to an integrated luminosity of 1.7  nb^{-1}. The measurement is performed in the rapidity and transverse momentum ranges |y|<1.6 and 15
  17. Mangano MC, Berlino M, Corbari L, Milisenda G, Lucchese M, Terzo S, et al.
    Environ Sci Policy, 2022 Jan;127:98-110.
    PMID: 34720746 DOI: 10.1016/j.envsci.2021.10.014
    The COVID-19 global pandemic has had severe, unpredictable and synchronous impacts on all levels of perishable food supply chains (PFSC), across multiple sectors and spatial scales. Aquaculture plays a vital and rapidly expanding role in food security, in some cases overtaking wild caught fisheries in the production of high-quality animal protein in this PFSC. We performed a rapid global assessment to evaluate the effects of the COVID-19 pandemic and related emerging control measures on the aquaculture supply chain. Socio-economic effects of the pandemic were analysed by surveying the perceptions of stakeholders, who were asked to describe potential supply-side disruption, vulnerabilities and resilience patterns along the production pipeline with four main supply chain components: a) hatchery, b) production/processing, c) distribution/logistics and d) market. We also assessed different farming strategies, comparing land- vs. sea-based systems; extensive vs. intensive methods; and with and without integrated multi-trophic aquaculture, IMTA. In addition to evaluating levels and sources of economic distress, interviewees were asked to identify mitigation solutions adopted at local / internal (i.e., farm-site) scales, and to express their preference on national / external scale mitigation measures among a set of a priori options. Survey responses identified the potential causes of disruption, ripple effects, sources of food insecurity, and socio-economic conflicts. They also pointed to various levels of mitigation strategies. The collated evidence represents a first baseline useful to address future disaster-driven responses, to reinforce the resilience of the sector and to facilitate the design reconstruction plans and mitigation measures, such as financial aid strategies.
  18. Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, Erö J, et al.
    Phys Rev Lett, 2021 Sep 17;127(12):122001.
    PMID: 34597080 DOI: 10.1103/PhysRevLett.127.122001
    The first measurement of the dependence of γγ→μ^{+}μ^{-} production on the multiplicity of neutrons emitted very close to the beam direction in ultraperipheral heavy ion collisions is reported. Data for lead-lead interactions at sqrt[s_{NN}]=5.02  TeV, with an integrated luminosity of approximately 1.5  nb^{-1}, are collected using the CMS detector at the LHC. The azimuthal correlations between the two muons in the invariant mass region 88.3. The back-to-back correlation structure from leading-order photon-photon scattering is found to be significantly broader for events with a larger number of emitted neutrons from each nucleus, corresponding to interactions with a smaller impact parameter. This observation provides a data-driven demonstration that the average transverse momentum of photons emitted from relativistic heavy ions has an impact parameter dependence. These results provide new constraints on models of photon-induced interactions in ultraperipheral collisions. They also provide a baseline to search for possible final-state effects on lepton pairs caused by traversing a quark-gluon plasma produced in hadronic heavy ion collisions.
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