Differential expression of genes during recovery of Nicotiana tabacum from tomato leaf curl Gujarat virus infection.

MAIN CONCLUSION: Nicotiana tabacum exhibits recovery response towards tomato leaf curl Gujarat virus. Transcriptome analysis revealed the differential expression of defense-related genes. Genes encoding for cysteine protease inhibitor, hormonal- and stress-related to DNA repair mechanism are found to be involved in the recovery process. Elucidating the role of host factors in response to viral infection is crucial in understanding the plant host-virus interaction. Begomovirus, a genus in the family Geminiviridae, is reported throughout the globe and is known to cause serious crop diseases. Tomato leaf curl Gujarat virus (ToLCGV) infection in Nicotiana tabacum resulted in initial symptom expression followed by a quick recovery in the systemic leaves. Transcriptome analysis using next-generation sequencing (NGS) revealed a large number of differentially expressed genes both in symptomatic as well as recovered leaves when compared to mock-inoculated plants. The virus infected N. tabacum results in alteration of various metabolic pathways, phytohormone signaling pathway, defense related protein, protease inhibitor, and DNA repair pathway. RT-qPCR results indicated that Germin-like protein subfamily T member 2 (NtGLPST), Cysteine protease inhibitor 1-like (NtCPI), Thaumatin-like protein (NtTLP), Kirola-like (NtKL), and Ethylene-responsive transcription factor ERF109-like (NtERTFL) were down-regulated in symptomatic leaves when compared to recovered leaves of ToLCGV-infected plants. In contrast, the Auxin-responsive protein SAUR71-like (NtARPSL) was found to be differentially down-regulated in recovered leaves when compared to symptomatic leaves and the mock-inoculated plants. Lastly, Histone 2X protein like (NtHH2L) gene was found to be down-regulated, whereas Uncharacterized (NtUNCD) was up-regulated in both symptomatic as well as recovered leaves compared to the mock-inoculated plants. Taken together, the present study suggests potential roles of the differentially expressed genes that might govern tobacco's susceptibility and/or recovery response towards ToLCGV infection.

Wilson's disease - a tricky diagnosis on the acute take.

Wilson's disease is a rare genetic disorder that affects copper metabolism in the body, leading to excess copper accumulation in various organs, including the liver and brain. It often presents to both primary and secondary care, with a combination of liver disease and neurological or psychiatric symptoms, but the presentation can be highly variable. Early recognition and treatment of Wilson's disease is important to prevent critical hepatic and neurological complications. In this case report, we describe the presentation of an 18-year-old male university student with a combination of dysphagia, tremors, and slurred speech, which progressed over several months. Through a series of investigations, the patient was diagnosed with Wilson's disease and received appropriate treatment. This report highlights the importance of considering Wilson's disease in patients with a wide range of symptoms and the need for a pragmatic approach to diagnosis, including routine and additional testing as necessary.

ARTIFICIAL INTELLIGENCE: CREATING NEW PARADIGMS IN THE MANAGEMENT OF NON-COMMUNICABLE DISEASES.

The role of Artificial Intelligence (AI) in medical science is growing immensely. Since AI contains features that can address both preventive and therapeutic aspects of non-communicable diseases (NCDs), it can potentially lessen the massive burden of morbidity and mortality associated with NCDs. AI can help in various ways in NCDs including predicting disease occurrence, monitoring, ensuring treatment and follow-up of patients. Low- and middle-income countries can harness the benefit of AI for the management of chronic diseases and effectively address challenges like manpower shortage, accessibility to health care, etc. However, AI needs to be used responsibly and rationally in NCDs for its maximum benefit.

Molecular simulation of linear octacosane via a CG10 coarse grain scheme.

Following our previous work on the united-atom simulation on octacosane (C28H58) (Dai et al., Phys. Chem. Chem. Phys., 2021, 23, 21262-21271), we developed a coarse grain scheme (CG10), which is able to reproduce the pivotal phase characteristics of octacosane with highly improved computational efficiency. The CG10 octacosane chain was composed of 10 consecutive beads, maintaining the fundamental zigzag chain morphology. When the potential functions were set up and the coefficients were parameterized, our CG10 models yielded solid phase diagrams and transitions during an annealing process. We also detected the melting point by various means: direct observation, bond order, density tracking, and an enthalpy plot. Furthermore, our CG10 successfully reproduced the liquid density with only 2% underestimation, indicating its applicability across the solid and liquid phases. Therefore, with the ability to reproduce critical structure and property characteristics, our CG10 scheme provides an effective means of numerically modelling octacosane with highly improved computational efficiency.

Use of geographical information systems (GIS) in assessing ecological profile, fish community structure and production of a large reservoir of Himachal Pradesh.

The present study demonstrates the spatial analysis and mapping of fish and different measures of environmental parameters and fish diversity of Pong reservoir, Himachal Pradesh, using Kriging spatial interpolation methods for geographical information system mapping. Seasonal data on environmental parameters, potential fish habitat and fish diversity was collected from lentic (dam), lentic (reservoir), transitional and lotic zone of the reservoir.. Important environmental parameters like water temperature, dissolved oxygen, electrical conductivity, water depth and transparency showed variations across the different zones of the reservoir. The sediment of the reservoir was sandy clay loam in nature as per texture analysis. Fish species richness, Shannon index and evenness index showed a similarity of the lotic and lentic (reservoir) zones of the reservoir. Six potential fish breeding grounds were identified in the reservoir indicating high conservation significance. The analysis of data showed a declining trend in fish production from 456.9 tonnes during the decade 1976-1987 to 347.91 tonnes during 2009-2020. The factors like anthropogenic climate change, predation of a stocked fish juvenile by water birds, undersized fish stocking and unscientific management are the probable reasons for the decreasing fish production. The spatial variation pattern of the water spread area, environmental parameters, fish catch and potential fish breeding grounds depicted in the GIS platform can be used as an important information base by the policy makers for fisheries management. The stocking of large size fish as a stocking material and adequate protection of the potential fish breeding grounds are the key advisories for the sustainable enhancement of fisheries as well as conservation.

Impact of plasma glucose and duration of type 2 diabetes mellitus on SYNTAX Score II in patients suffering from non ST-elevation myocardial infarction.

Aim    The objective was to assess the correlation of fasting plasma glucose (FPG), HbA1c, and the duration of type 2 diabetes mellitus (T2DM) with SYNTAX score (SS) II in patients with non-ST elevation myocardial infarction (NSTEMI).Material and methods    FPG and HbA1C were measured in 398 patients presenting with NSTEMI at admission. SS II was calculated using an online calculator. Patients were stratified according to SS II (≤21.5, 21.5-30.6, and ≥30.6), defined as SS II low, mid, and high, respectively.Results    37.7 % of subjects were diabetic. Correlations of FPG (R=0.402, R2=0.162, p<0.001) and HbA1c (R=0.359, R2=0.129, p<0.001) with SS II were weak in the overall population. Duration of T2DM showed very strong correlation with SS II (R=0.827, R2=0.347). For the prediction of high SS II in the study population, FPG≥98.5 mg / dl demonstrated a sensitivity of 58 % and a specificity of 60 %, and HbA1c ≥6.05 demonstrated a sensitivity of 63 % and a specificity of 69 %. Duration of T2DM (adjusted odds ratio (OR): 1.182; 95 % confidence interval (CI): 1.185-2.773) and FPG (OR: 0.987; 95 % CI: 0.976-0.9959) were significantly associated with high SS II after controlling for other risk factors. Duration of T2DM (Beta=0.439) contributed strongly to variance of SS II, whereas HbA1c (Beta=0.063) contributed weakly.Conclusion    Duration of T2DM is a very important risk factor for severity of coronary artery disease.

Development and evaluation of onion bulb descaler for removal and collection of surface dry peel.

Onion bulbs contain outer papery dry peel which is rich with industrially important high-value compounds. Removal of dry peel/scale of onion is the common practice during bulb processing, storage and marketing. A conventional manual method of scale removal involves huge labour, drudgery and means of environmental pollution. An onion descaler machine has been therefore developed to mechanize this operation, reduce drudgery and effectively collect the dry scales for industrial use. The operating parameters of the developed machine were optimized for its best performance using RSM. During optimization study, roller speed, roller slope and hopper opening were taken as independent variables. The performance of the machine was evaluated through descaling efficiency and descaling loss. During experimentation, descaling efficiency and descaling loss were obtained in the range of 35.92-98.55% and 0.82-9.07%. The optimum performance of the machine was obtained at 450 rpm roller speed, 2% roller slope and 380 mm of the hopper opening with maximum descaling efficiency (88.29%) and minimum descaling loss (3.65%). The optimization of the onion descaler parameters and their statistical relation provided the necessary information on the combination of material-machine alignment, and design parameters for enhanced descaling efficiency. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-021-05264-5.

Molecular dynamics simulation of octacosane for phase diagrams and properties via the united-atom scheme.

We used the united-atom scheme to build three types of crystalline structures for octacosane (C28H58) and carried out molecular dynamics simulations to investigate their phase properties. By gradually heating the three polymorphs, we managed to reproduce the sequence of experimentally reported crystalline phases and rotator phases. By studying the system density, molecule morphology, chain tilt angle and cell anisotropy, we hypothesized three mechanisms behind the observed system deformations and phase transformations during the annealing process. Furthermore, our model successfully predicted the melting temperature and heat of fusion. We also reproduced the characteristics of the rotator phases and the liquid phase, validating the transferability of the united-atom scheme among the different condensed phases of octacosane. Our methodology represents an effective and efficient means of numerical study for octacosane and may be used for other members of the n-alkane family.

Subcallosal haemorrhage as a sign of diffuse axonal injury in patients with traumatic brain injury.

AIM: To identify the relationship between subcallosal haemorrhage and diffuse axonal injury (DAI) grading. MATERIALS AND METHODS: Computed tomography (CT) and magnetic resonance imaging (MRI) images of all patients with traumatic brain injury over the past 5 years were reviewed. Subcallosal haemorrhage was defined as the presence of haemorrhage on admission CT underneath the corpus callosum. Grading of DAI was performed using MRI or CT exclusive of subcallosal haemorrhage status. The association of demographic factors, mechanism of injury, Glasgow Coma Scale (GCS) on admission, and positive subcallosal haemorrhage status with the presence of moderate-severe DAI was assessed. Receiver operating characteristic (ROC) curve analysis was used to evaluate the performance of subcallosal haemorrhage status in predicting DAI severity. Median modified Rankin Scale (mRS) scores were compared between subcallosal haemorrhage positive and negative cases. RESULTS: The images of 1,150 patients were reviewed with 301 patients showing DAI. Of those, 64 patients (21.2%) and 237 patients (78.7%) were positive and negative for subcallosal haemorrhage, respectively. Isolated subcallosal haemorrhage was noted in 15 patients (23.4%). A subcallosal haemorrhage positive status (OR=5.16, p < 0.001) was statistically significantly associated with moderate-severe DAI. The ROC curve for predicting moderate-severe DAI with subcallosal haemorrhage status showed an area under the curve of 0.625 (95% confidence interval [CI]: 0.561-0.688, p < 0.001). The median mRS score was significantly higher (p < 0.001) in the subcallosal haemorrhage positive group (median 4.5, interquartile range [IQR] 2-6) versus the negative group (median 2, IQR 2-3). Isolated subcallosal haemorrhage group showed moderate-severe DAI in 80% (12/15) of cases. CONCLUSION: Subcallosal haemorrhage is a highly specific radiographic predictor of moderate-severe DAI (grade 2-3).

Multidrug resistant staphylococci isolated from pigs with exudative epidermitis in North eastern Region of India.

Exudative epidermatitis or greasy pig disease (GPD) is a contagious disease of pig and endemic worldwide caused by toxigenic strains under genus Staphylococcus. The present study reported an outbreak of GPD in Champhai district of Mizoram adjoining to the southern border of Myanmar. A total of 60 samples were collected from 22 clinically affected animals and processed for isolation and identification of Staphylococcus spp. All the isolates were subjected to antimicrobial sensitivity assay, biofilm production assay and detection of virulence genes, biofilm genes and mec genes followed by cloning and sequencing for phylogenetic analysis. A total of 44 staphylococci belonged to four species (S. sciuri, S. aureus,S. lentus, and S. hyicus) were isolated. Majority of the isolates were multidrug resistant with maximum resistance against ampicillin, penicillin including vancomycin. None of the S. hyicus isolates was methicillin resistant (MRSH) but 66·67% isolates were MRSA. By PCR, mecA gene was detected in S. aureus (n = 2), S. sciuri (n = 4) and S. lentus (n = 3). Biofilm associated gene icaD was detected in S. aureus (n = 3), S. sciuri (n = 5), S. hyicus (n = 4) and S. lentus (n = 6). The exfoliative toxin genes (ehxB, shetA and tsst1) were detected in S. hyicus (n = 3) and S. aureus (n = 1) isolates. All the isolates were closely related with the isolates from pigs of China, Germany, Japan and USA. The pathogens might be transmitted through illegal migration of pigs from Myanmar to India.

Interacting Genetic Lesions of Melanoma in the Tumor Microenvironment: Defining a Viable Therapy.

Melanoma is the most aggressive form of skin cancer with an estimated 106,110 newly diagnosed cases in the United States of America in 2021 leading to an approximated 7180 melanoma-induced deaths. Cancer typically arises from an accumulation of somatic mutations and can be associated with mutagenic or carcinogenic exposure. A key characteristic of melanoma is the extensive somatic mutation rate of 16.8 mutations/Mb, which is largely attributed to UV exposure. Bearing the highest mutational load, many of them occur in key driver pathways, most commonly the BRAFV600E in the mitogen-activated protein kinase (MAPK) pathway. This driver mutation is targeted clinically with FDA-approved therapies using small molecule inhibitors of oncogenic BRAFV600E and MEK, which has greatly expanded therapeutic intervention following a melanoma diagnosis. Up until 2011, therapeutic options for metastatic melanoma were limited, and treatment typically fell under the spectrum of surgery, radiotherapy, and chemotherapy.Attributed to the extensive mutation rate, as well as having the highest number of neoepitopes, melanoma is deemed to be extremely immunogenic. However, despite this highly immunogenic nature, melanoma is notorious for inducing an immunosuppressive microenvironment which can be relieved by checkpoint inhibitor therapy. The two molecules currently approved clinically are ipilimumab and nivolumab, which target the molecules CTLA-4 and PD-1, respectively.A plethora of immunomodulatory molecules exist, many with redundant functions. Additionally, these molecules are expressed not only by immune cells but also by tumor cells within the tumor microenvironment. Tumor profiling of these cell surface checkpoint molecules is necessary to optimize a clinical response. The presence of immunomodulatory molecules in melanoma, using data from The Cancer Genome Atlas and validation of expression in two model systems, human melanoma tissues and patient-derived melanoma cells, revealed that the expression levels of B and T lymphocyte attenuator (BTLA), TIM1, and CD226, concurrently with the BRAFV600E mutation status, significantly dictated overall survival in melanoma patients. These molecules, along with herpesvirus entry mediator (HVEM) and CD160, two molecules that are a part of the HVEM/BTLA/CD160 axis, had a higher expression in human melanoma tissues when compared to normal skin melanocytes and have unique roles to play in T cell activation. New links are being uncovered between the expression of immunomodulatory molecules and the BRAFV600E genetic lesion in melanoma. Small molecule inhibitors of the MAPK pathway regulate the surface expression of this multifaceted molecule, making BTLA a promising target for immuno-oncology to be targeted in combination with small molecule inhibitors, potentially alleviating T regulatory cell activation and improving patient prognosis.

Posterior spinal cord indentation: imaging findings and clinical outcome.

AIM: To identify the imaging findings associated with worse clinical outcome in posterior spinal cord indentation. MATERIALS AND METHODS: A retrospective search for cases of dorsal cord indentation on magnetic resonance imaging (MRI) from April 2009 to March 2016 was undertaken. Imaging follow-up and clinical data were recorded. Two neuroradiologists blinded to the clinical data assessed the imaging findings. Differences and association of imaging and clinical findings were assessed via t-test and Fisher's exact and chi-squared tests for continuous and categorical data. Inter-rater agreement was calculated. RESULTS: Seventy-three patients were included, 65 were clinically stable, or the finding was incidental and eight had clinical worsening or required surgery. There was a significant difference in the percentage of cord diameter decrease between the two clinical groups (p=0.013, reader 1; p=0.027 reader 2). The clinical course was significantly associated with subjective cord indentation depth assessment (p=0.03 reader 1) and presence of syrinx (p=0.017 reader 2) on original MRI and worsening on imaging follow-up (p=0.03). The interrater agreement was moderate for syrinx identification (k=0.58). There was only fair agreement for the scalpel sign classification and in the final diagnosis (k=0.35 and 0.28). CONCLUSION: The degree of cord indentation, the presence of syrinx, and worsening of imaging findings on follow-up are associated with worse clinical course and can be useful in guiding management and directing subspecialty referrals.

Correction to: Development of a new reproductive tissue cryopreservation clinical service for children: the Oxford programme.

In the published version, the Acknowledgements section was missing a funding note of co-author Dr C Verrill. The corrected version should read as follows.

Imaging of the Spontaneous Low Cerebrospinal Fluid Pressure Headache: A Review.

Spontaneous intracranial hypotension (SIH) is a significant cause of chronic, postural headaches. Spontaneous intracranial hypotension is generally believed to be associated with cerebrospinal fluid (CSF) leaks, and these leaks can be posttraumatic, iatrogenic, or idiopathic in origin. An integral part of the management of patients with this condition consists of localizing and stopping the leaks. Radiologists play a central role in the workup of this condition detecting leaks using computed tomography, magnetic resonance imaging, or nuclear imaging. In this article, we briefly review SIH and the various imaging modalities, which can be used to identify and localize a spontaneous CSF leak.

Participation of Phosphatidylinositol-3 Kinase Signalling in Human Chorionic Gonadotropin, Bovine Insulin (B-Insulin) and Human-Insulin-Like Growth Factor-I Induced Oocyte Maturation and Steroidogenesis in the Grey Mullet, Mugil Cephalus.

CONTEXT: The grey mullet, Mugil cephalus, is an edible fish of high economic importance. Breeding biology with reference to hormonal/growth factor regulation of oocyte maturation needs to be known for its commercial production. OBJECTIVE: The present study was conducted to examine the potency of maturation inducing hormones, chorionic gonadotropin (hCG), bovine-insulin, and insulin like growth factor1 (h-IGF-1) I on ovarian steroidogenesis and oocyte maturation. DESIGN: The role of hormones and growth factors on steroidogenesis and oocyte maturation was investigated using specific inhibitors, Wortmannin for phosphatidylinositol-3 (PI3) kinase, trilostane for 3ß-hydroxysteroid dehydrogenase, 1-octanol and 1-heptanol for gap junctions, actinomycin D for transcription and cycloheximide for translation of signal molecules. METHODS: Actions of hormonal and growth factors were examined for steroidogenesis, by radioimmunoassay and oocyte maturation by germinal vesicle breakdown (GVBD). Specific inhibitors were used to determine the cell signaling pathways, PI3 kinase. RESULTS: All the inhibitors attenuated the hCG-induced oocyte maturation (GVBD%), steroidogenesis including transcription, translation, gap junctions and PI3 kinase signaling. These inhibitors failed to inhibit h-IGF-I and b-insulin-induced oocyte maturation, steroidogenesis, translation and PI3 kinase signaling. CONCLUSION: hCG induces oocyte maturation via steroid dependent pathway involving gap junctions, transcription, translation and PI3 kinase signaling, unlike h-IGF-I and b-insulin in the mullet.

Molecular structure of a hyperactive antifreeze protein adsorbed to ice.

Antifreeze proteins (AFPs) are a unique class of proteins that bind to ice crystal surfaces and arrest their growth. The working mechanism of AFPs is not well understood because, as of yet, it was not possible to perform molecular-scale studies of AFPs adsorbed to the surface of ice. Here, we study the structural properties of an AFP from the insect Rhagium mordax (RmAFP) adsorbed to ice with surface specific heterodyne-detected vibrational sum-frequency generation spectroscopy and molecular dynamic simulations. We find that RmAFP, unlike other proteins, retains its hydrating water molecules upon adsorption to the ice surface. This hydration water has an orientation and hydrogen-bond structure different from the ice surface, thereby inhibiting the insertion of water layers in between the protein and the ice surface.

Extended spectrum beta-lactamase producing Shiga-toxin producing-Escherichia coli in piglets, humans and water sources in North East region of India.

Extended spectrum ß-lactamases (ESBL) producing Shiga toxin producing E. coli (STEC) are posing a constant threat to public health throughout the world leading to serious infections and raising key therapeutic issues. A total of 219 fecal samples were collected from piglets with diarrheoa, pig farmers and water sources in North East India; and were processed for isolation of Escherichia coli. The isolates were screened for antimicrobial resistance and suspected isolates for ESBLs production by double-disk synergy test (DDST). Escherichia coli isolates positive for DDST were subjected for detection of selected ESBL/beta-lactamase genes and virulence associated genes by PCR. By DDST, 337 (67·94%) E. coli isolates were detected as ESBLs producer, of which 211 (66·98%), 117 (70·91%) and 9 (56·25%) isolates were from piglets, humans and water sources respectively. A total of 64 (12·90%) isolates were recorded as STEC, of which 48 (9·68%), 6 (1·21%) and 10 (2·02%) were from human, piglets and water respectively. Majority of the STEC isolates (64·06%) possessed multiple virulence genes, of which 59·38% also harboured ESBL/beta-lactamase genes with 32·81% STEC isolates being positive for multiple ESBL/beta-lactamase genes. SIGNIFICANCE AND IMPACT OF THE STUDY: Multidrug resistant (MDR) enteric bacteria are global concern. Association of MDR traits in STEC isolates are another rising issue in human and animal health perspective. The interaction of such organisms among the human, domestic animals and adjoining water sources require to be analysed systematically. The present study exhibited the possible transmission of MDR-STEC among the human, domestic animals and water sources in the North eastern states of India. To the best of our knowledge, this is the first report of such kind in India.

Development of a new reproductive tissue cryopreservation clinical service for children: the Oxford programme.

PURPOSE: This article describes the development of a new reproductive tissue cryopreservation clinical service for children at high risk of infertility in the NHS during times of severe financial constraints in the health service. METHOD: A development plan with two phases was drawn up. Phase 1 restricted the service to childhood cancer patients referred to the Oxford Paediatric Oncology and Haematology Principle Treatment Centre. It was estimated that there would be 10 patients/year and used existing staff and facilities from paediatric oncology, surgery, anaesthetics radiology, pathology, psychology, teenage-young adult gynaecology, and an existing Human Tissue Authority tissue bank with a licence for storage of tissue under a Human Sector Licence. Phase 2 extended the service to include children and young adults across England, Wales and Ireland-patients from Scotland having access to a research programme in Edinburgh. The main challenge in phase 2 being resources and the need for patients to be able to be treated as close to home as safely as possible. RESULTS: The Oxford team developed information resources and eligibility criteria based on published best practice, referral and treatment pathways, multidisciplinary team meetings, a network of third party sites, and a dedicated case management and database. As the programme expanded, the Oxford team was able to justify to management the need for a dedicated theatre list. Patient feedback through questionnaires, qualitative work conducted as part of a Ph.D. thesis as well as direct patient stories and interviews in TV, and radio features underpins the positive impact the programme has on patients and their families. CONCLUSION: The Oxford Reproductive Cryopreservation programme delivers fertility preservation treatment to children and young adults at high risk of infertility safely, effectively and as close to home as possible. The onward view is to apply for national funding for this programme for recognition and sustainability.

Effect of environment on spatio-temporal structuring of fish assemblages in a monsoon-influenced tropical estuary.

This study analyzes the trophic structure of fish assemblages in a well-mixed tropical estuary, Zuari, located in southwest coast of India. A total of 224 fish species were collected between September 2013 and August 2016 from 324 sampling events from 9 sampling stations using surface and bottom set gillnets. The sampling events were designed to cover three major seasons such as the pre-monsoon, monsoon, and post-monsoon. For each sampling event, abiotic variables such as temperature, salinity, dissolved oxygen, and transparency of the water were recorded. The data obtained for abundance of fish species was subjected to cluster analysis and non-metric multidimensional scaling. The results defined six spatio-temporally varying groups (clusters) within Zuari estuary. Canonical correspondence analysis demonstrated that temperature, salinity, dissolved oxygen, and transparency were important in determining the fish assemblages in Zuari. The estuarine resident species were abundant in the inner zone (riverine side) of the estuary, where the salinity and temperature recorded lower dimensions compared to middle and outer zones (marine side). However, the inner shallow zone of the estuary was not a preferred habitat for the migrating marine species. Majority of the fish species preferred middle and outer zones and post-monsoon and pre-monsoon seasons for inhabiting the estuary. The present study furnishes a reference data for the spatio-temporal dynamics of fish assemblages in tropical monsoonal estuaries.

Diurnal and seasonal patterns of soil CO2 efflux from the Pichavaram mangroves, India.

The diurnal and seasonal variation of soil carbon dioxide (CO2) flux was measured in the Pichavaram mangrove forest, the Southeast coast of India from February 2016 to October 2016 using an automated soil CO2 flux chamber system. Maximum soil CO2 efflux reached at 14:00 h and minimum at 00:00 h. The surface soil CO2 concentration ranged from 375 to 532 ppm with the mean 405 ± 18 ppm. The daily soil CO2 flux varied from near zero to about 7 µmol m-2 s-1 with a mean value of 2.4 ± 1.3 µmol m-2 s-1. The highest seasonal CO2 efflux from soil was during the summer and premonsoon seasons, whereas low flux values were recorded during the monsoon season. Soil CO2 efflux values were highly correlated with soil temperature. Tidal inundation during monsoon season, extreme drought condition in summer, and unusual precipitation are the major factors controlling the soil CO2 flux.