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The Telok Melano, Sarawak (Malaysia), and Temajuk, West Kalimantan (Indonesia) border communities existed in the early 1980’s has created a unique communication pattern in West Borneo. In the early stages, both speakers in Telok Melano-Temajuk had spoken a similar language variation called Malay Sambas dialect. After four decades of the border community formation (1980-2020), the communication pattern in both areas has experienced a significant change. Thus, the objective of this study is to analyse the cross-border communication pattern of Telok Melano-Temajuk based on Gilles’ Communication Accommodation Theory. Research data were obtained using qualitative approach through recordings, interviews, and participant observations. There are five dialogue samples obtained from the speakers from Telok Melano-Temajuk for analysis. Every interaction in the dialogue was analysed using convergence and divergence strategy to identify the border community communication pattern in West Borneo. The study found the border community communication pattern in West Borneo had contributed to the integration phenomenon and language variation choice in daily interaction of two community groups living in proximity but separated by international border. From the communication accommodation perspective, the communication pattern at Telok Melano-Temajuk is different according to the informant’s age. The older generation at Telok Melano was found to use the convergence strategy when interacting with speakers from Temajuk by switching from Telok Melano Malay dialect to Desa Temajuk Malay dialect. On the other hand, the younger generation at Telok Melano was found to begin its transition to the Sarawak Malay dialect, specifically the Kuching variation which is Sarawak’s lingua franca. The finding in this study is important to record the border community’s communication pattern transition after the opening of the Telok Melano-Sematan alignment of the Pan-Borneo Highway. [ABSTRACT FROM AUTHOR]

The preprocessing of diffusion magnetic resonance imaging (dMRI) data involve numerous steps, including the corrections for head motion, susceptibility distortion, low signal‐to‐noise ratio, and signal drifting. Researchers or clinical practitioners often need to configure different preprocessing steps depending on disparate image acquisition schemes, which increases the technical threshold for dMRI analysis for nonexpert users. This could cause disparities in data processing approaches and thus hinder the comparability between studies. To make the dMRI data processing steps transparent and adapt to various dMRI acquisition schemes for researchers, we propose a semi‐automated pipeline tool for dMRI named integrated diffusion image operator or iDIO. This pipeline integrates features from a wide range of advanced dMRI software tools and targets at providing a one‐click solution for dMRI data analysis, via adaptive configuration for a set of suggested processing steps based on the image header of the input data. Additionally, the pipeline provides options for post‐processing, such as estimation of diffusion tensor metrics and whole‐brain tractography‐based connectomes reconstruction using common brain atlases. The iDIO pipeline also outputs an easy‐to‐interpret quality control report to facilitate users to assess the data quality. To keep the transparency of data processing, the execution log and all the intermediate images produced in the iDIO's workflow are accessible. The goal of iDIO is to reduce the barriers for clinical or nonspecialist users to adopt the state‐of‐art dMRI processing steps. [ABSTRACT FROM AUTHOR]

With the advancement of digital technology, the world's languages are undergoing significant changes. Facebook, Instagram, Twitter, blogs, and other social media platforms are examples of today's communication mediums. These social media platforms are the main mode of communication in today's culture. The purpose of this research is to look at the meaning expansions of Malay words on Facebook. The study included three common Malay terms as examples: kafir, kunyit, and sibuk. These terms were chosen using the purposive sample approach, and Google Trends was used to validate the current usage trends. Keller's (1994) Invisible Hand theory was used to analyze this research. Keller proposes that specific motives of language users cause the emergence of a new meaning for a word. According to analysis, these three words are frequently used on Facebook, and their new meanings are diverged from their original meanings, namely kafir > "unislamic," kunyit > "refers to gay," and sibuk > "continously do sth". Following viralization in social media by Facebook users, the new meaning formation of these three selected words appears to have occurred drastically and altered in a short period of time. This phenomenon appears to be characterized by an invisible hand. Words having new meanings are eventually propagated, recognized, and widely utilized by social media users. This research contributes to Malay lexicography by promoting awareness of how the meanings of contemporary words have altered drastically as a result of the emergence of online social media, a phenomenon that presents a threat to traditional Malay lexicography. [ABSTRACT FROM AUTHOR]

Amebic dysentery caused by Entamoeba histolytica accounts for significant morbidity in the non-human primates (NHP) at the Singapore Zoo. This includes the animals in the collection as well as a sizeable free-roaming wild crab-eating macaque (Macaca fascicularis) population. The disease is of great concern because of its zoonotic potential. Passive surveillance, both ante and post-mortem, of NHP displaying clinical symptoms and active surveillance of NHP assessed to be at a higher risk of infection were carried out via fecal real-time polymerase chain reaction (PCR) testing for 4 years. Treatment of the disease with 25 mg/kg metronidazole BID for 10 days followed by 15 mg/kg paromomycin BID for 7 days achieved good clinical resolution in most cases that tested positive. Three diseased NHP with severe clinical signs of weight loss, lethargy, and diarrhea were anesthetized for veterinary diagnostic investigation. Mesenteric lymphadenopathy was consistently seen on ultrasound examination in these severe cases of entamoebiasis. Two animals eventually died of severe chronic enteritis due to the disease. The eradication of entamoebiasis in the NHP at the Singapore Zoo may be complicated by the maintenance of a disease reservoir in wildlife, but a combination of timely treatment and efforts at maintaining biosecurity can help manage the disease in the collection. [ABSTRACT FROM AUTHOR]

Accurate and complete replication of the genome is essential not only for genome stability but also for cell viability. However, cells face constant threats to the replication process, such as spontaneous DNA modifications and DNA lesions from endogenous and external sources. Any obstacle that slows down replication forks or perturbs replication dynamics is generally considered to be a form of replication stress, and the past decade has seen numerous advances in our understanding of how cells respond to and resolve such challenges. Furthermore, recent studies have also uncovered links between defects in replication stress responses and genome instability or various diseases, such as cancer. Because replication stress takes place in the context of chromatin, histone dynamics play key roles in modulating fork progression and replication stress responses. Here, we summarize the current understanding of histone dynamics in replication stress, highlighting recent advances in the characterization of fork-protective mechanisms. [ABSTRACT FROM AUTHOR]

We report a case of fatal Chryseobacterium indologenes infection in a captive juvenile red‐shanked Douc langur in Singapore Zoo. The animal was treated for suspected melioidosis but died within 48 h. Chryseobacterium indolegenes was isolated from the liver and should be included as a differential for bacterial infections in the tropics. [ABSTRACT FROM AUTHOR]

Suhaid language is spoken in Seberuang and Suhaid river basins, Western Kalimantan (Indonesia). This language exhibited its uniqueness with the C+h (consonant + glottal fricative) sound system, which is similar to the aspirated occlusive voice. This aspirated occlusive is derived from the deletion of /É™/ in the penultimate syllable position. Since in Suhaid, r is correspondence to /h/, the C+h form will formed after the deletion of schwa. This paper discusses the existence of the aspirated occlusive voice from the perspective of Optimality phonology. This study has consolidated that this theory is a practicable approach to explain the generation of two different output after the deletion of schwa. This study found that in a disyllabic input, this deletion of schwa has lead to a floating mora which later being attached to immediate vowel and formed a vowel lengthening. On the other hand, for the trisyllabic input, the floating mora will attach to the onset nearby and produce a geminate consonant. This consonant later will undergo the process of degemination, segmental coalescence and eventually appeares as a breathy voiced in the output. Based on analysis, the *GEM (NO GEMINATE) and *COMPLEX ONSET (no more than one segment may associate to any one syllabic constituent) constraints played crucial role in terms of constraint satisfaction and violation. All the candidates with geminate consonant will be ruled out as fatal violation since *GEM dominates the other contraints in the constraint hierarchy. *COMPLEX ONSET on the other hand is an additional constraint that play specific roles to generate dwisyllabic output (from trisyllabic input). This constraint (as well as other constraints) will eliminates all the /C+h/ candidates and the candidate with breathy voice which fully satisfies the given constraint is the optimal candidate. [ABSTRACT FROM AUTHOR]

In the manufacturing system, machines and manufacturing data are becoming more closely linked. In order to collect manufacturing data, there have been many new technologies that are in line with the Industrial Revolution 4.0 to replace existing systems and machines. The objective of this study is to design a sensor system that can collect and stream machine data from an end milling machine to generate a manufacturing report. A prototype of this system was designed using a Raspberry Pi Model 3 B+, PiCamera module, and infrared sensors for installing onto the machine, while Microsoft Azure and Power BI were used to stream and publish the data in a report form. The design was placed onto a milling machine where a machinist had done one milling operation for one workpiece, the sensors collected the data of X-position, Y-position, feed rate, and spindle speed, while deriving the percentage utiliza t ion of total time for cutting steps. The end result was a system that was integrated with the milling machine where the critical operation data are collected to produce a manufacturing report that displays the use of the machine. For future studies, different applications for this kind of sensor system can be used to digitize different manufacturing systems. Furthermore, an optimiza t ion and standardization testing for this kind of manufacturing system could be set in the future as well. [ABSTRACT FROM AUTHOR]

Background: Diffusion tensor imaging (DTI) is a novel MRI technique that enables noninvasive evaluation of microstructural alterations in white matter of brain. Initially, DTI was used in intra- or inter-hemispheric association bundles. Recent technical advances are overcoming the challenges of imaging small white matter bundles, such as the cranial nerves. In this study, we use DTI to shed more light on the microstructure changes in long-standing trigeminal neuralgia. We also utilize DTI to study the effect of early stereotactic radiosurgery (SRS) on the microstructures of the trigeminal nerve and to predict the effectiveness of early SRS in the treatment of medically refractory trigeminal neuralgia (TN).Methods: To analyze the presentation of trigeminal nerve, the DTI was reconstructed in 21 cases pre- and post-SRS. DTI parameters recorded include fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), axial diffusivity (AD), linear anisotropy coefficient (Cl), planar anisotropy coefficient (Cp), and spherical anisotropy coefficient (Cs). Comparisons between ipsilateral (symptomatic) and contralateral (asymptomatic) trigeminal nerves and symptom durations of < 5 and ≧ 5 years were performed.Results: The study cohort comprised 21 patients with TN with a median age of 66 years. Initial adequate facial pain relief (Barrow Neurological Institute facial pain scores I-IIIb) was achieved in 16 (76%) patients. For the pre-SRS DTI findings, ipsilateral trigeminal nerve was associated with higher baseline root entry zone (REZ) Cs compared to contralateral nerve (0.774 vs. 0.743, p = 0.04). Ipsilateral trigeminal nerve with symptoms of < 5 years was associated with higher baseline FA compared to trigeminal nerve with symptoms of ≧ 5 years (0.314 vs. 0.244, p = 0.02). For the post-SRS DTI findings, ipsilateral trigeminal nerves with symptoms of <5 years demonstrated decrease in Cl, while those with symptoms ≧ 5 years demonstrated increase in Cl after SRS at the ipsilateral REZ (− 0.025 vs. 0.018, p = 0.04). At the cisternal segment of ipsilateral trigeminal nerve, symptoms of < 5 years were associated with decreased FA and increased λ2, while symptoms of ≧ 5 years were associated with increased FA and decreased λ2 after SRS (FA − 0.068 vs. 0.031, p = 0.04, λ2 0.0003 vs. − 0.0002, p = 0.02).Conclusions: SRS provides high rates of initial pain relief with moderate rates of facial hypoesthesia. Ipsilateral trigeminal nerve was associated with higher baseline REZ Cs, and baseline FA was associated with duration of symptoms. There were significant associations between duration of symptoms and changes in ipsilateral REZ Cl, cisternal segment FA, and cisternal segment λ2 after SRS. These preliminary findings serve as comparisons for future studies investigating the use of DTI in radiosurgical planning for patients with TN. [ABSTRACT FROM AUTHOR]

This study presents the framework of the acceleration reference continuous motion nominal characteristic trajectory following (AR‐CM NCTF) control system, and its effectiveness in a linear motion mechanism with friction characteristics is experimentally demonstrated in comparison with the other control methods. The overall control system comprises the feedback‐loops for velocity reference and acceleration reference following controls. The AR‐CM NCTF control is an enhanced continuous motion NCTF (CM NCTF) control that has been proposed for high‐precision motion. It has the same structure as the CM NCTF controller with additional elements for high‐precision motion. The design procedure of the AR‐CM NCTF controller remains easy and is independent of friction characteristics. The usefulness and advantages of the proposed controller are shown in the experimental studies. Besides, this study also highlights the robustness of the AR‐CM NCTF controller by examining its performances in point‐to‐point and tracking motions in the presence of mass and disturbance force variations. In the robust performance, the AR‐CM NCTF controller is compared with two types of proportional derivative control systems with disturbance observers (PDDOs). The comparative experimental results illustrate that the AR‐CM NCTF controller shows the higher motion performances the higher robustness to plant parameter variations than the PDDO controllers. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an improved practical controller for enhancing precision motion performance. For practical use, high motion control performance and ease of controller design are desired. A nominal characteristic trajectory following control (NCTF control) has been studied to satisfy the desired response. The NCTF controller consists of a nominal characteristic trajectory (NCT) which is the reference motion of control system and a compensator which makes the motion of the controlled object to follow the NCT. The NCT is easily determined from experimental open-loop time responses of the mechanism. The controller parameters can be also determined easily, without any given model parameters. In the present paper, the Continuous Motion NCTF controller for high continuous motion performance is improved in order to enhance the following characteristic of the object motion on NCT and improve the positioning and tracking accuracies of the system. The improved Continuous Motion NCTF controller (referred to as Acceleration Reference-Continuous Motion NCTF controller (AR-CM NCTF controller)) provides the advantages such as the high overshoot reduction characteristics and the low sensitivity disturbance. The AR-CM NCTF controller includes the structure of the Continuous Motion NCTF controller and acceleration reference for the object motion as the additional controller elements. The design procedure of the AR-CM NCTF controller remains easy and practical. In order to confirm the advantages, the AR-CM NCTF controller was examined in positioning and tracking motion performances using the non-contact mechanism. The experimental results prove that the AR-CM NCTF controller achieves the better positioning and tracking performances than the Continuous Motion NCTF controller. [ABSTRACT FROM AUTHOR]

Abstract: In this contribution, a practical controller design for non-contact mechanism and contact mechanism is discussed. The design procedure is applicable and totally independent of friction characteristic. Thus, designer does not need to consider the friction characteristic of a mechanism and it is a valuable controller approach in industry. The practical controller design procedure which based on current Nominal Characteristic Trajectory Following (NCTF) controller is proposed and improved. The NCTF controller is comprehensive, comprising of a Nominal Characteristic Trajectory (NCT) and a PI compensator, which is free from exact modeling and parameter identification. In NCTF controller design, the NCT is constructed from the open-loop responses of the mechanism. The designed input signal for open-loop experiment is needed to satisfy the following two conditions: (1) the displacement by the input signal must be smaller than the working range of the mechanism to avoid any damage to the mechanism; (2) the suitable input signal needs to produce sufficient rapid and smooth response during deceleration to satisfy the desired specifications because the response significantly influences the reference following characteristic of the control system. So far, the NCTF controllers had been implemented to the mechanisms which have sufficient large damping characteristics and it was natural to satisfy the condition (1). However, non-contact and low damping mechanisms do not have sufficient damping characteristics. Since the high damping characteristics of the mechanism have been used before, the condition (2) is still not yet been considered. Therefore, the design procedure of the input signal satisfying the two conditions is proposed and verified by experiments in this paper. The common conditions of the input signal which is independent of friction characteristic of the mechanisms are discussed. Then, the experimental verifications are performed using non-contact mechanism and contact mechanism. In this paper, the performance evaluation is discussed separately in two parts. In part 1, by using the non-contact mechanism, the positioning results of two different NCTs are compared in order to show the usefulness of the modified suitable input. In part 2, the contact mechanism is used to show the effectiveness of the NCTF controller with its simple and practical design procedure, which is independent of friction characteristic. The effectiveness of the Continuous Motion NCTF controller is verified with the PID controller experimentally in positioning control and tracking control. The experimental results prove that the displacements of the open-loop responses for NCTs are always smaller than the working range and the design procedure of the input signal is successfully independent of the friction characteristic of the mechanism. Overall, the Continuous Motion NCTF controller which has simple and practical design procedure exhibits the high performance in positioning and tracking control with contact mechanism and non-contact mechanism, as compared to the PID controller. The PID controller shows the low adaptability in motion control performances for both conditions of mechanism. [Copyright &y& Elsevier]

Microfluidic‐assisted synthesis of nanoparticles has generated significant interest for its precise control and high throughput capabilities. Among various nanomaterials, gold nanoparticles (AuNPs) have shown remarkable potential in numerous applications, such as disease detection, photothermotherapy, drug delivery, and even defense applications. Recent synthesis strategy of peptide‐mediated method has sparked greater interest by offering unique chiroptical properties and their applications in biomedical applications. In this study, the use of droplet microfluidics is explored for the synthesis of peptide‐mediated AuNPs, aiming to accelerate automated production via flow chemistry. This method leads to the formation of anisotropic gold particles, with sizes ranging from hundreds of nanometers to the micron scale. The interfacial energy is identified at the water/oil interface as a critical factor influencing this outcome, with L‐glutathione (L‐GSH) playing a significant role in the development of hyper‐branched structures. These results demonstrate the capability of droplet microfluidics in producing anisotropic gold particles at micron scales, presenting new possibilities for the advancement of nanoparticle synthesis techniques. [ABSTRACT FROM AUTHOR]

Background: Subjective cognitive decline (SCD) is an early stage of dementia linked to Alzheimer's disease pathology. White matter changes were found in SCD using diffusion tensor imaging, but there are known limitations in voxel-wise tensor-based methods. Fixel-based analysis (FBA) can help understand changes in white matter fibers and how they relate to neurodegenerative proteins and multidomain behavior data in individuals with SCD. Methods: Healthy adults with normal cognition were recruited in the Northeastern Taiwan Community Medicine Research Cohort in 2018–2022 and divided into SCD and normal control (NC). Participants underwent evaluations to assess cognitive abilities, mental states, physical activity levels, and susceptibility to fatigue. Neurodegenerative proteins were measured using an immunomagnetic reduction technique. Multi-shell diffusion MRI data were collected and analyzed using whole-brain FBA, comparing results between groups and correlating them with multidomain assessments. Results: The final enrollment included 33 SCD and 46 NC participants, with no significant differences in age, sex, or education between the groups. SCD had a greater fiber-bundle cross-section than NC (pFWE < 0.05) at bilateral frontal superior longitudinal fasciculus II (SLFII). These white matter changes correlate negatively with plasma Aβ42 level (r = −0.38, p = 0.01) and positively with the AD8 score for subjective cognitive complaints (r = 0.42, p = 0.004) and the Hamilton Anxiety Rating Scale score for the degree of anxiety (Ham-A, r = 0.35, p = 0.019). The dimensional analysis of FBA metrics and blood biomarkers found positive correlations of plasma neurofilament light chain with fiber density at the splenium of corpus callosum (pFWE < 0.05) and with fiber-bundle cross-section at the right thalamus (pFWE < 0.05). Further examination of how SCD grouping interacts between the correlations of FBA metrics and multidomain assessments showed interactions between the fiber density at the corpus callosum with letter-number sequencing cognitive score (pFWE < 0.01) and with fatigue to leisure activities (pFWE < 0.05). Conclusion: Based on FBA, our investigation suggests white matter structural alterations in SCD. The enlargement of SLFII's fiber cross-section is linked to plasma Aβ42 and neuropsychiatric symptoms, which suggests potential early axonal dystrophy associated with Alzheimer's pathology in SCD. The splenium of the corpus callosum is also a critical region of axonal degeneration and cognitive alteration for SCD. [ABSTRACT FROM AUTHOR]

Since 2020, the coronavirus disease 2019 (COVID-19) pandemic has seen many changes in our daily infection prevention behaviours so as to reduce healthcare-associated transmission of COVID-19 in patients and healthcare workers. In the early phases of the COVID-19 pandemic of 2020, there was much emphasis on compliant personal protective equipment utilization in the operating theatres (OTs) for COVID-19-positive patients. However, during this period, there was a lack of international validated protocols on the appropriate handling and subsequent storage of personal protective equipment in the context of aerosol-generating procedures in OTs for asymptomatic antigen rapid test (ART)-negative patients. Given the potential for transmission even with a negative ART due to the incubation period, our team developed a checklist of eye protection (e.g. goggles/face shield) and N95 mask handling and storage in non-isolation OTs for these patients. We sought to improve the compliance of best practices from 20% to 80% amongst junior anaesthetists in Singapore General Hospital so as to prevent infection transmission and cross-contamination in the OT through education and behaviour-changing interventions. This quality improvement project took place over 19 weeks from June to October 2020 by our team of anaesthetists and nurse clinicians in the non-isolation OT setting. To analyse the problem, we performed a root cause analysis to understand attitudes and beliefs driving their behaviour. The top 80% of cited root causes for non-compliance then guided prioritization of resources for subsequent behaviour-changing interventions. Using the comprehensive infection control checklist, we conducted several plan-do-study-act cycles while implementing this new checklist amongst junior anaesthetists. A total of 227 assessments of junior anaesthetists were made in the care of asymptomatic ART-negative patients. Compliance with correctly handling goggles post-intubation started out as 33.3% in Week 1, which improved to 78.5% by Week 19. Compliance with goggle storage and face shield disposal started out at 13.6% in Week 1 and increased to 78.6% by Week 19. We attributed this improvement to education and behaviour-changing interventions. This quality improvement project focusing on improving compliance with personal protective equipment utilization during the COVID-19 pandemic in the management of asymptomatic ART-negative patients in non-isolation OTs demonstrated the importance of interventions of education, persuasion, modelling, and training in effecting and sustaining organizational behaviour change in physicians and other healthcare personnel. [ABSTRACT FROM AUTHOR]

Introduction. Adhesive tapes are used for taping eyelids closed and securing endotracheal tubes during general anesthesia. These tapes can cause facial skin injury. We compared the incidence of facial skin injury and patient satisfaction with different tapes used. Methods. A total of 60 adult patients at risk of skin trauma were randomized to use 3M™ Kind Removal Silicone Tape or standard acrylate tapes: 3M Durapore (endotracheal tube) and Medipore (eyelids). Patients were blinded to tape used. Postoperatively, a blinded recovery nurse assessed erythema, edema, and denudation of skin. Anesthesiologist in charge also assessed skin injury. On postoperative day 1, patients rated satisfaction with the condition of their skin over the eyelids and face on a 5-point Likert scale. Results. More patients had denudation of skin with standard tapes, 4 (13.3%) versus 0 with silicone tape (p=0.026) and in anesthesiologist-evaluated skin injury 11 (37%) with standard versus 1 (3%) with silicone (p=0.002). No significant differences were found in erythema and edema. Patient satisfaction score was higher with silicone tape: over eyelids: mean 3.83 (standard) versus 4.53 (silicone), Mann-Whitney U test, p<0.001; over face: mean 3.87 (standard) versus 4.57 (silicone) (p<0.001). Conclusion. Silicone tape use had less skin injury and greater patient satisfaction than standard acrylate tapes. [ABSTRACT FROM AUTHOR]

Objective To evaluate effectiveness of early Gamma Knife radiosurgery (GKRS) in treatment of medically refractory trigeminal neuralgia (TN). Methods This retrospective review comprised 108 consecutive patients with medically refractory idiopathic TN between 2006 and 2014. All patients underwent GKRS targeting the root entry zone with a median maximum dose of 90 Gy and isodose line of 20%. Outcomes pertaining to pain and facial numbness were scored using Barrow Neurological Institute scales. Results Following a median latency period of 4 weeks, we observed complete or adequate pain relief (Barrow Neurological Institute scores of I–IIIB) in 86 of 108 patients (90%). At a median time of 17 months, 22 patients (26%) experienced pain recurrence. New-onset facial numbness was reported by 59 patients (55%). Treatment failure rates were highest among patients with a longer history of pain. Compared with patients with pain history of ≤5 years, patients with pain history of >5 years experienced longer latency before pain relief ( P = 0.027). Univariate and multivariate analyses demonstrated that pain history of ≤5 years was a significant predictor of pain relief ( P = 0.049 and P = 0.045, respectively). Conclusions GKRS achieves a high rate of pain relief among patients with medically refractory idiopathic TN. Pain history of ≤5 years is a reliable predictor of pain relief and appears to be associated with shorter latency to pain relief after GKRS. Therefore, early GKRS for patients with medically refractory idiopathic TN is recommended. [ABSTRACT FROM AUTHOR]

Koi herpesvirus (KHV) is the causative agent of a highly infectious and notifiable disease of Cyprinus carpio L. Serology has the potential to identify koi or carp that have been previously exposed to KHV and which may be possible carriers of the virus. In the present study, sera (n = 162) from groups of farmed koi carp, previously screened for KHV using a variety of molecular methods as part of a surveillance program in Asia from 2008 to 2010, were subsequently tested here individually by ELISA using plates coated with purified virus (American isolate KHV-I, H361). Only 31% of koi from PCR-positive KHV fish groups or populations associated with KHV disease (n = 59/162) were seropositive when screened in the ELISA at a serum dilution of 1/200, in contrast to 52.9% of seropositive koi that were KHV-negative by PCR (n = 103/162). Furthermore >34% of those seropositive/PCR negative fish had titres of >1/400 (moderate-strong responders). This field data highlights the concerns related to carp populations that have been screened for KHV using molecular methods alone and supports the need for serology to accompany molecular testing in carp for this notifiable virus. • Koi serum samples were screened for KHV by ELISA from a surveillance programme using PCR • Only 31% of koi from PCR-positive KHV cases were seropositive by ELISA at a serum dilution of 1/200 • In contrast 52.9% of koi were seropositive that were KHV-negative by PCR (34% with titres >1/400) • Field data supporting ELISA as a reliable complementary diagnostic to molecular testing for KHV [ABSTRACT FROM AUTHOR]

Background: Lates calcarifer, known as seabass in Asia and barramundi in Australia, is a widely farmed species internationally and in Southeast Asia and any disease outbreak will have a great economic impact on the aquaculture industry. Through disease investigation of Asian seabass from a coastal fish farm in 2015 in Singapore, a novel birnavirus named Lates calcarifer Birnavirus (LCBV) was detected and we sought to isolate and characterize the virus through molecular and biochemical methods. Methods: In order to propagate the novel birnavirus LCBV, the virus was inoculated into the Bluegill Fry (BF-2) cell line and similar clinical signs of disease were reproduced in an experimental fish challenge study using the virus isolate. Virus morphology was visualized using transmission electron microscopy (TEM). Biochemical analysis using chloroform and 5-Bromo-2′-deoxyuridine (BUDR) sensitivity assays were employed to characterize the virus. Next-Generation Sequencing (NGS) was also used to obtain the virus genome for genetic and phylogenetic analyses. Results: The LCBV-infected BF-2 cell line showed cytopathic effects such as rounding and granulation of cells, localized cell death and detachment of cells observed at 3 to 5 days' post-infection. The propagated virus, when injected intra-peritoneally into naïve Asian seabass under experimental conditions, induced lesions similar to fish naturally infected with LCBV. Morphology of LCBV, visualized under TEM, revealed icosahedral particles around 50 nm in diameter. Chloroform and BUDR sensitivity assays confirmed the virus to be a non-enveloped RNA virus. Further genome analysis using NGS identified the virus to be a birnavirus with two genome segments. Phylogenetic analyses revealed that LCBV is more closely related to the Blosnavirus genus than to the Aquabirnavirus genus within the Birnaviridae family. Conclusions: These findings revealed the presence of a novel birnavirus that could be linked to the disease observed in the Asian seabass from the coastal fish farms in Singapore. This calls for more studies on disease transmission and enhanced surveillance programs to be carried out to understand pathogenicity and epidemiology of this novel virus. The gene sequences data obtained from the study can also pave way to the development of PCR-based diagnostic test methods that will enable quick and specific identification of the virus in future disease investigations. [ABSTRACT FROM AUTHOR]