Community-level analysis of anthropogenic impacts on rocky shore communities in Sri Lanka

Human activities threat seashore communities in many areas of the world and their impacts on coastal ecosystem are a matter of increasing concern. Present study describes the anthropogenic disturbances on the rocky shore community structure by comparing the benthic communities of disturbed and non-disturbed areas in Sri Lanka where rocky shores remain virtually untouched so far by experimental studies. Impacts of human disturbances; trampling, handling and exploitation on the community structure of rocky macro benthic assemblages were tested in high-, mid- and low-intertidal area by stratified sampling method at Rumassala marine sanctuary and adjacent two localities at either side of the marine sanctuary, Galle and Unawatuna. Univariate measures, log series model and multivariate techniques were used to discriminate the communities with respect to the disturbances. Proximity of study localities and indistinguishable physicochemical parameters of sea surface water (temperature, Salinity, conductivity, dissolved oxygen and pH) indicated that overall environment of the study area was relatively uniform and changes in community structure was due to human disturbances. Human disturbances documented as visitor censuses by transect walk method lead to categorize the Rumassala as non-disturbed, Unawatuna as disturbed with Galle being of moderately disturbance. Community abundance showed a decreasing trend along with increasing disturbances, albeit community biomass, due to opportunistic algae species, increased in parallel to disturbances. Computed Index of disturbance revealed that macrofauna was very sensitive to the disturbances and increased disturbances reduced their competitive pressure on macroalgae, leading to outstanding macroalgal growth. Macroalgal domination in disturbed communities contributed to lessen the heterotrophic dominance in Galle and Unawatuna. 96 macrobenthic taxa were encountered from the study and Species richness, Shannon and Fisher’s diversity index showed decreasing trend with increasing disturbances. Moreover, initial rising slope of species accumulation curves for three communities indicated that community evenness was low in disturbed communities. The community compositions from dominant conservative species to fast growing opportunistic species were well described by the log series model, showing left skewed distribution. The SIMPER analysis further confirmed that most biomass dominant species in stress status were the opportunistic species such as Valoniopsis pachynema, Gracilaria cassa and Padina boerggesenii. Providing strong support to the results highlighted from univariate measures and log series model, multivariate cluster analysis and nMDS plots completely separated three communities at ordinal scale. This separation was further confirmed by one-way ANOSIM test with significantly higher (2.9%) similarity of study sites within each community. Present study indicated that, allowing less time for recovery, human activities created press-type disturbance on macro-benthic assemblages, and subsequent changes in community structure could be attributed to less suitable substrata. Study proposed that ecological stress is the best measured by multiple methods, and results from different approaches provide the robustness necessary to judge the reliability of the conclusion. Present study strongly supports the growing concern that human activities impact on intertidal assemblages all over the world by changing community composition. Present finding is a contribution to the published literature that is scarcer from tropical rocky shores

Performance Evaluation of Adaptive Continuous Wavelet Transform based Rake Receiver for UWB Systems

This paper proposes an adaptive continuous wavelet transform (ACWT) based Rake receiver to mitigate interference for high speed ultra wideband (UWB) transmission. The major parts of the receiver are least mean square (LMS) adaptive equalizer and N-selective maximum ratio combiner (MRC). The main advantage of using continuous wavelet rake receiver is that it utilizes the maximum bandwidth (7.5GHz) of the UWB transmitted signal, as announced by the Federal Communication Commission (FCC). In the proposed ACWT Rake receiver, the weights and the finger positions are updated depending upon the convergence error over a period in which training data is transmitted. Line of sight (LOS) channel model (CM1 from 0 to 4 meters) and the Non line of sight (NLOS) channel models (CM, CM3 and CM4) are the indoor channel models selected for investigating in this research . The performance of the proposed adaptive system   is evaluated by comparing with conventional rake and continuous wavelet transform (CWT) based rake. It showed an improved performance in all the different UWB channels (CM1 to CM4) for rake fingers of 2, 4 and 8. Simulations showed that for 8 rake fingers, the proposed adaptive CWT rake receiver has shown an SNR improvement of 2dB, 3dB, 10dB and 2dB respectively over CWT rake receiver in different UWB channels CM1, CM2, CM3 and CM4

OFDM Channel Estimation Along with Denoising Approach under Small SNR Environment using SSA

In this paper, a de-noising approach in conjunction with channel estimation (CE) algorithm for OFDM systems using singular spectrum analysis (SSA) is presented. In the proposed algorithm, the initial CE is computed with the aid of traditional linear minimum mean square error (LMMSE) algorithm, and then further channel is evaluated by considering the low rank eigenvalue approximation of channel correlation matrix related to channel using SSA. Simulation results on bit error rate (BER) revealed that the method attains an improvement of 7 dB, 5 dB and 3 dB compared to common LSE, MMSE and SVD based methods respectively. With the help of statistical correlation coefficient (C) and kurtosis (k), the SSA method utilized to de-noise the received OFDM signal in addition to CE. In the process of denoising, the received OFDM signal will be decomposed into different empirical orthogonal functions (EOFs) based on the singular values. It was established that the correlation coefficients worked well in identifying useful EOFs only up to moderate (SNR geq 12dB). For low SNR<12 dB, kurtosis was found to be a useful measure for identifying the useful EOFs. In addition to outperforming the existing methods, with this de-noising approach, the mean square error (MSE) of channel estimator is further improved approximately 1 dB more in SNR at the cost of computational complexity

Effect of in situ soil moisture conservation practices on maize and its crop residue incorporation on yield and economics of succeeding transplanted rice Var. ADT 46

Crop residue incorporation is a key component of sustainable cropping systems. It reduces the adverse effects of residue burning and enhances soil fertility. Effective usage of crop residue in the field and proper management are required. With this background, a field experiment was conducted during 2020 – 21 in the maize-rice cropping sequence at Annamalai University Experimental Farm, Department of Agronomy, Faculty of Agriculture, Annamalai University, Annamalai Nagar, Tamil Nadu to find out the residual effect of different mulching practices adopted in preceding maize crop and maize stubble incorporation on the growth, yield and economics of transplanted rice Var. ADT 46. The field experiment was conducted in Factorial Randomized Block Design with three replications. In factor I, soil moisture conservation in preceding maize crop viz., mulching of sugarcane trash, water hyacinth, hydrogel and control were allotted. In factor II, different levels of maize crop stubble incorporation on rice viz., 0, 33, 66 and 100% were provided. Water hyacinth mulched plot (M3) to the preceding crop registered significantly (þ &lt;0.05) higher yield parameters, yield and economic returns of succeeding rice. The lower values were observed in unmulched (M1) plot. With respect to maize crop stubble incorporation on rice crop, the incorporation of 66% (SI3) of maize stubble registered higher yield parameters, yield and economic returns. In the interaction effects, mulching with water hyacinth to preceding maize + maize crop stubble incorporation at 66% in rice crop (M3SI3) recorded significantly (þ &lt;0.05) higher yield parameters, yield and economic returns than other treatments. The lowest values were recorded with an unmulched + 100% crop residue incorporated (M1SI4) plot. Mulching the preceding maize crop with water hyacinth at a rate of 12 t ha-1 and incorporating 66% maize stubble into the transplanted rice (M3SI3) had a remarkable yield advantage and financial rewards

Signless Laplacian polynomial for splice and link of graphs

The signless Laplacian matrix of a graph G is Q(G) = A(G) + D(G), where A(G) is the adjacency matrix and D(G) is the diagonal degree matrix of a graph G. The characteristic polynomial of the signless Laplacian matrix is called the signless Laplacian polynomial. The present work is all about the study of signless Laplacian polynomial for the splice of more than two graphs and the link of such graphs. It is noted that such a study is easier when we take into account of the vertex set partition being an equitable partition, because equitable partition of the vertex set reduces the computational steps and also the quotient matrix polynomial is a part of the polynomial of a graph. In this paper we consider the splice and links of complete graphs and of complete bipartite graphs and obtain the signless Laplacian polynomial of these using equitable partition of the vertex set.Publisher's Versio

A Comparative Analysis of Psychiatric Profile, Depression and Body Dysmorphic Disorder in patients with Amputation and Post Stroke.

INTRODUCTION: Amputation is defined as the removal of extremities of body part by trauma or by Surgical procedure. Amputees may feel empty, and mutilated. Amputation due to Trauma is a catastrophic injury and causes major disability in most of the cases (Wald 2004)1. Loss of limb is associated with low self-esteem, body image Disturbance, social isolation and also a sense of stigmatization (William et al. 2004). In many conditions amputation is unavoidable. Irrespective of the aetiology, Amputation is considered as a mutilating surgery and it definitely affects the lives Of the patients (De Godoy et al. 2002). Limb amputation is a more commonly Occurring event in the present society. The loss of a limb distorts the individual’s body image leading to the thought of Not being a complete human being. The loss of the functions performed with that Limb renders him helpless for sometime. The amputee not only loses physical Functioning, he also loses hope and future aspirations, his plans and ambitions get Shattered. Thus, he loses not only a limb but also a part of his world and future. Most of them remain anxious and worried about their interpersonal relationship in The social, vocational, familial and marital milieu. Individuals having an overt Mental breakdown will need active psychiatric intervention whereas careful Psychiatric interview is necessary for the ones whose mental symptoms are not so Obvious. Limb loss is a major event that can severely impact the psychological health of the Individual concerned. Studies show that 20-60% of the amputees attending follow Up clinics are assessed to be clinically depressed. Individuals with traumatic Amputation irrespective of the age are likely to suffer from body image problems, But these findings are more common in younger individuals. The psychological Reactions to amputation are clearly diverse ranging from severe disability at one Extreme; and a determination to effectively resume a full and active life at other End. In adults the age at which an individual receives the amputation is an Important factor. Studies by Bradway JK et al (1984)2, Kohl SJ Et al (1984)3, Livneh H (1999)4, on the psycho-social adaptation to amputation has led to a Plethora of clinical and empirical findings. Kingdon D et al 1982 equated Amputation with loss of one’s perception of wholeness, while (Parkes CM 1976)5 With loss of spouse and (Block WE et al (1963)6 with symbolic castration & even Death. The individual’s response to a traumatic event is influenced by personality Traits, pre-morbid psychological state, gender, peri-traumatic dissociation, Prolonged disability of traumatic events, lack of social support and inadequate Coping strategies. Previous studies on amputation mainly focused on demographic Profile, coping skills and outcome; with there being a scarcity of literature on Prevalence of various specific psychiatric disorders in the post-amputation period. Most patients with a limb loss irrespective of whether due to traumatic injury or Surgical procedures go through a series of complex psychological reactions Reported by Cansever et al (2003)8. Most people try to cope with it, those who Don’t succeed develop psychiatric symptoms Frank et al (1984)7. Shukla et Al9 noted that psychological intervention in some form is needed in about 50% of All amputees, and Shukla et al9 reported depression to be the most common Psychological reaction following amputation. The three major problems faced by many amputees are anxiety, depression and Physical disability (Green 2007) Horgan & maclachlan (2004)10 found that anxiety is associated with depression, Low self esteem, poorer quality of life and higher level of general anxiety. Both Anxiety and depression are associated with higher disability as age increases. Body image is the combination of psychosocial adjustment and attitude of the Individual that are related to the function and appearance of one’s own body which Can be influenced by the individual and his environmental factors (Horgan & Maclachlan 2004)10. Each person has an idealized body image, which he uses for Measuring perceptions and concepts of his or her own body (Fishman, 1959)11. From another perspective, Flannery & Faria (1999) body image is viewed as a Dynamic, changing phenomenon occurring in a person and it is formed by the Constantly changing perceptions about his body. According to Newell (1991)13, Attractive people after amputation will receive less reinforcement from others Leading to low self-esteem and reduced positive self-image. Jacobsen et al (1997) Supports this stating i.e. Amputation leads to disfigurement which in turn leads to a Negative body image and greater loss of social acceptance. The relationship Between disability experience and stigma are interwoven and inter-dependent. The Reason for the amputee’s subjective perception of being unfit for the society Probably is that body image provides a sense of ‘’self’ ’and also affects the Persons thinking (Wald 2004)1. According to Kolb (1975)14, changes in body Image may cause series of psychological reactions. The psychiatric aspect of amputation has received scant interest in our country, in Spite of accidental injuries being common (Shukla et al., 1982)9. The commonest Psychiatric disorder seen in amputees is major depression. Randall et al. (1945)15 Have reported an incidence of 61 % in non-battle casualties, while Shukla et al. (1982)9 found depressive neurosis (40%) and psychiatric depression (22%) to be The leading psychiatric disorders in amputees; only 35% of the total sample in the Later study had nil psychiatric disorders. The paucity of literature in this field has Prompted us to study about amputation and its co morbid psychiatric conditions so That proper care & management for the patients can be planned. The present study Was undertaken with the aim of studying the psychiatric problems especially Anxiety, depression and Body Dysmorphic Disorder which may be associated with Disability or changed life circumstances in the immediate post-amputation period. A comparison was made with Stroke patients, as these patients often experience Physical and social handicaps similar to amputees. Depression is the most common mood disorder to follow stroke (Starkstein & Robinson, 1989), with major depression affecting around one quarter to one third Of patients (Hackett16).. Depression hampers functional recovery in a post stroke individual. In Diagnostic And statistical manual (DSM) IV Post Stroke Depression classified under “mood Disorder due to general medical condition (i.e. Stroke)” with the specific depressive Features, major depressive-like episodes, manic features or mixed features. Studies Describe that cerebral ischemia is associated with two types of depressive disorder. Incidence of major and minor depression is 25% and 30% respectively. Prevalence May vary over time with an apparent peak 3months after the stroke and Subsequently decline in prevalence at 1 year. Robinson and colleagues studies Showed a spontaneous remission in the natural course of major depression Occurring post stroke in the first to second year following stroke. However in few Cases depression may become chronic and persist for a longer period. While some propose that post stroke depression is due to stroke affecting the Neural circuits concerned with mood regulation (thereby supporting a primary Biological mechanism), others in the scientific community claim it to be due to the Ensuing psycho-social stressors occurring as a result of stroke. Though an Integrated bio- psycho- social model is warranted, most studies clearly suggest Biological mechanism to have an upper hand in the later post stroke period than in The immediate phase. In the same way Anxiety is also common in post stroke individuals with the Incidence rate being 20%, and it is most common in first three to four months after The stroke. Studies and literatures on post stroke anxiety are very few still remain in its Infancy. Studies have concentrated on socio-demographic variables, cognitive Functions and laterality as examined for post stroke depression. Many studies show That there is correlation between anxiety and right hemisphere lesions and also that Co-morbid post stroke anxiety and depression are associated with left hemisphere Lesions [Astrom, (1996)17]. Many studies have shown the relationship between post Stroke anxiety, age and gender. Women and younger individuals are more Vulnerable to develop post stroke anxiety (Morrison, walter et al 200069), while Another study reports no such relationship (Schultz et al).1

Discovery of unusual pulsations in the cool, evolved Am stars HD 98851 and HD 102480

The chemically peculiar (CP) stars HD 98851 and HD 102480 have been discovered to be unusual pulsators during the ``Naini Tal Cape Survey'' programme to search for pulsational variability in CP stars. Time series photometric and spectroscopic observations of these newly discovered stars are reported here. Fourier analyses of the time series photometry reveal that HD 98851 is pulsating mainly with frequencies 0.208 mHz and 0.103 mHz, and HD 102480 is pulsating with frequencies 0.107 mHz, 0.156 mHz and 0.198 mHz. The frequency identifications are all subject to 1 d$^{-1}$ cycle count ambiguities. We have matched the observed low resolution spectra of HD 98851 and HD 102480 in the range 3500-7400 \AA with theoretical synthetic spectra using Kurucz models with solar metallicity and a micro-turbulent velocity 2 km s$^{-1}$. These yield $T_{eff}=7000\pm250$ K, log $g=3.5 \pm 0.5$ for HD 98851 and $T_{eff} = 6750 \pm 250$ K, log $g = 3.0 \pm 0.5$ for HD 102480. We determined the equivalent H-line spectral class of these stars to be F1 IV and F3 III/IV, respectively. A comparison of the location of HD 98851 and HD 102480 in the HR diagram with theoretical stellar evolutionary tracks indicates that both stars are about 1-Gyr-old, 2-$M_{\odot}$ stars that lie towards the red edge of the $\delta$ Sct instability strip. We conclude that HD 98851 and HD 102480 are cool, evolved Am pulsators. The light curves of these pulsating stars have alternating high and low amplitudes, nearly harmonic (or sub-harmonic) period ratios, high pulsational overtones and Am spectral types. This is unusual for both Am and $\delta$ Sct pulsators, making these stars interesting objects.Comment: 9 pages, 6 Figures, Accepted for publication in MNRA

Partially oxidized ferrocenyl complexes for nonlinear optics

Second-order nonlinearity (p) in a series of partially oxidized bisferrocenes linked through conducting -C=N- linkages has been measured and found to vary linearly with the redox potential difference between the ferrocene moiety and the oxidant