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Background:: Corynebacterium striatum is an emerging nosocomial pathogen, capable of causing a variety of infections in immunocompromised and hospitalized patients. Case Presentation: We describe three cases of infection by C. striatum that were initially considered as contamination. Clinical suspicion in the wake of predisposing factors and accurate identification, using the Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS), were key to implicate this commensal bacterium as a cause of infection.

Background: Non-tuberculous mycobacterial (NTM) infections have been drawing interest recently because of their rising incidence not Non-tuberculous mycobacterial (NTM) infections have been drawing interest recently because of their rising incidence not only in immunocompromised but also in immunocompetent individuals. These are underdiagnosed in India, due to the lack of awareness and a low index of suspicion. In regions endemic for tuberculosis (TB) such as India, presumptive anti-tubercular treatment (ATT) is often prescribed. Non-response of NTM to the treatment may be wrongly ascribed to multidrug-resistant tuberculosis. This emphasizes the need to correctly identify them before initiating therapy.only in immunocompromised but also in immunocompetent individuals. These are underdiagnosed in India, due to lack of awareness and a low index of suspicion. In regions endemic for tuberculosis (TB) such as India, presumptive anti-tubercular treatment (ATT) is often prescribed. Non-response of NTM to the treatment may be wrongly ascribed to multidrug-resistant tuberculosis. This emphasizes the need to correctly identify them before initiating therapy. We describe the case of a young, healthy female patient who developed cervical lymphadenitis and was given presumptive ATT. Microbiological examination of aspirate revealed M. fortuitum. This not only rectified the course of treatment resulting in complete cure, but also spared the patient from significant side effects of ATT. This case is an awakening call for clinicians to avoid presumptive ATT. Case Study: We describe the case of a young, healthy female patient who developed cervical lymphadenitis and was given presumptive ATT. Microbiological examination of aspirate revealed M. fortuitum. This not only rectified the course of treatment resulting in complete cure, but also spared the patient from significant side effects of ATT. This case is an awakening call for clinicians to avoid presumptive ATT.

Acinetobacter species are widely distributed in soil, water and hospital environment. In addition to A. calcoaceticus-baumannii complex, the clinically most relevant species, there are other genomospecies which are less frequently identified, mostly due to lack of accurate methods for routine identification. We describe the first case of post-traumatic endophthalmitis caused by otherwise non-pathogenic A. radioresistens, in India. Gram-negative coccobacilli were observed on Gram stain and culture of vitreous fluid specimen, and identified biochemically as Acinetobacter spp. The species was identified by Matrix Assisted Laser Desorption Ionization- Time of Flight Mass Spectrometry (MALDI-TOF MS). The pathogenic potential of ‘commensal’ A. radioresistens and its role in dissemination of carbapenem resistance genes underlines the importance of species-level identification in Acinetobacter infections.

P-SV seismic acquisition requires 3C geophones and thus has greater cost compared with conventional P-P data. However, some companies justify this added cost because P-SV data provide an independent set of S-wave measurements, which can increase the reliability of subsurface property estimation. This study investigates SV-P data generated by a vertical vibrator and recorded by vertical geophones as a cost-effective alternative to traditional P-SV data. To evaluate the efficacy of the SV-P mode relative to the P-P and P-SV modes, multicomponent seismic data from Wellington Field, Kansas, were interpreted. P-P amplitude variation with offset (AVO) gathers and stacked SV-P seismic data were jointly inverted to estimate elastic properties, which were compared with the estimates obtained from joint inversion of P-P AVO gathers, stacked P-SV seismic data, and inversion of P-P AVO gathers data. All inversions provide identical P-impedance characteristics. However, a significant improvement in S-impedance estimates is observed when P-P and converted wave data (either SV-P or P-SV) are inverted jointly, compared with P-P inversion results alone. In the Arbuckle interval, which is being considered for [Formula: see text] injection, use of converted-wave data clearly demarcates the Middle Arbuckle baffle zone and the Lower Arbuckle injection zone, with the latter having low P- and S-impedances. These observations, although consistent with other well-based geologic evidence, are absent on P-P-only inversion results. No major difference in the inversion results is seen when SV-P data are used instead of P-SV data. Moreover, we determine for the first time by comparing the SV-P image obtained from vertical-vibrator data and the SV-P image obtained from horizontal-vibrator data that both data image subsurface geology equivalently, except for the important distinction that the former contains more valuable higher frequencies than the latter. Because legacy P-wave data can be reprocessed to extract the SV-P mode, using SV-P data can provide a unique way to perform multicomponent seismic analysis.

S-wave amplitude variation with offset (AVO) analysis is sensitive to the presence of fractures and can provide a high-resolution seismic-based fracture characterization as compared with traditionally used traveltime-based methods. To determine viable attributes for estimation of properties such as spatial density and fluid fill of fractures, S-wave AVO modeling and analysis is carried out in the Wellington Field, Kansas, where 9C-2D seismic data have been acquired. Analysis is performed on the Ordovician fractured-carbonate interval called the Arbuckle Group, which is being considered for [Formula: see text] sequestration. AVO modeling of the Arbuckle interval indicates that differences in AVO intercepts of different S-wave polarizations can estimate S-wave anisotropy parameter [Formula: see text], which gives an estimate of fracture density. In addition, modeling suggests that AVO gradients of [Formula: see text] and [Formula: see text] waves can be used to derive a seismic attribute to discriminate fluid fill in fractures, provided good-quality S-wave gathers are available. The intercept anisotropy (IA) attribute obtained from AVO intercepts of S-waves provides fracture density estimates within the Arbuckle Group. These estimates are consistent with the field-wide, low-frequency observations from seismic velocities and spatially limited, high-frequency estimates obtained from drill cores and sonic and borehole-image logs. The IA attribute highlights possible high-permeability zones in the Upper and Lower Arbuckle suitable for [Formula: see text] injection. The Middle Arbuckle indicates low fracture density, potentially acting as a baffle to vertical flow and providing a seal for the Lower Arbuckle. The gradient anisotropy attribute obtained from the AVO gradient of S-waves suggests that most fractures in the Arbuckle are brine saturated. This attribute has a potential application in monitoring the movement of a [Formula: see text] plume in the Arbuckle Group when time-lapse data become available. These results demonstrate that S-wave AVO attributes can supplement the P-wave derived subsurface properties and significantly reduce uncertainties in subsurface fracture characterization.

Background:Burkholderia cepacia complex is widespread in the environment and has been recognized as a cause of opportunistic pulmonary infections, particularly in patients with Cystic Fibrosis (CF). The natural ecology of the bacteria as part of plant growth-promoting rhizosphere provides stark contrast to its infectious potential. Its preponderance as a nosocomial pathogen may be due to its ability to survive in antiseptic solutions, contaminate equipments and intrinsic antimicrobial resistance.Case:An elderly, diabetic male was evaluated for hemoptysis, fever and cough. Chest computed tomography showed a thick walled cavity in the left lung and hilar lymphadenopathy. Sputum examination showed Gram negative bacilli and no acid fast bacilli. Sputum culture yielded growth of non-fermentative Gram negative bacilli on two occasions, but blood culture was sterile. The isolate was identified as B. cepacia by Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS). The patient’s general condition remained poor and in spite of initiation of antibiotics, the patient expired after an episode of massive hemoptysis.Conclusion:This report raises concerns regarding the spread and severity of B. cepacia infection in non-compromised patients in the community and the need to suspect and identify it. Since the organism is inherently resistant to antipseudomonal penicillins, aminoglycosides and polymyxin B, differentiation from Pseudomonas spp. and determining antimicrobial susceptibility is paramount for treatment..

Infection is an important cause of mortality in burns. Emergence of multi drug resistant pathogens in hospital setting has seriously constrained the available therapeutic options. This necessitates periodic review of the isolation pattern and study of antibiogram of the isolates to strengthen surveillance activities. To determine the bacteriological profile and antimicrobial susceptibility pattern of pathogens isolated from infected burn wounds of patients admitted in the burns care unit. The present study was carried out over a duration of six months. Pus samples from infected burn wounds were processed following standard protocols. Antimicrobial susceptibility of the bacterial isolates was performed by Kirby- Bauer disc diffusion method. A total of 408 bacterial pathogens were isolated from 340 samples. The most frequent cause of infection was found to be Pseudomonas aeruginosa (53%), followed by Staphylococcus aureus (9%), Escherichia coli (9%), Enterobacter spp. (8%), Citrobacter spp. (8%), Klebsiella spp. (5%), Acinetobacter spp. (3%) and Proteus spp. (3%). High level of drug resistance (95-100%) was observed for cefepime, ceftazidime, amoxyclav, cotrimoxazole and doxycycline among gram negative pathogens. Meropenem, amikacin and ciprofloxacin were found to be most effective. Twenty one percent of the S. aureus isolates were resistant to methicillin. The high prevalence of antimicrobial resistance emphasizes the need for strengthening the infection control practices

Summary This study focuses on the effects of fractures on the elastic properties of a rock and illustrates which P-wave and Swave Amplitude Variation with Offset (AVO) attributes might be helpful for quantitative interpretation of fracture properties like fracture-orientation, fracture-density and fracture-fill. A statistical rock physics model is constructed for Ordovician age carbonates of the Arbuckle Formation, encountered in wells drilled in the Wellington Field, Kansas. Our model incorporates a priori information about matrix porosity distribution and pore shapes obtained from well logs and analysis done on drill cores. Estimations of Pwave and S-wave seismic velocities and anisotropy parameters obtained from rock physics models, are used to study AVO behaviors of P-waves and fast and slow Swaves in directions parallel to, and perpendicular to fractures. AVO modeling shows that azimuthal variations in S-S mode AVO gradient can be used to determine the average fracture-orientation at a subsurface location; whereas, azimuthal variations in P-P mode AVO attributes are less than the uncertainty of lithology and fracturedensity, which limits the ability of P-waves to determine fracture-orientation. Results of this study demonstrate that in angle and azimuth space, the AVO intercept attribute of slow-S-wave in the plane parallel to fractures, quantitatively estimates the (crack density) parameter of a rock formation. In contrast, P-P azimuthal AVO attributes do not correlate well with crack density. This study also demonstrates that the AVO gradient of slow S-wave in direction normal to fracture-orientation is a seismic attribute for discriminating fluid fill in fractures. Conclusively, S-wave AVO attributes are less affected by subsurface uncertainty compared to P-wave attributes and hence can significantly reduce ambiguity in quantitative fracture characterization.

Summary A 4D seismic survey was carefully planned, executed and interpreted on the Ravva Field. Geoscience and 4D seismic studies carried out on the field have provided key information that defines fault compartments, position of the current OWC and reveals potential undrained areas. The 4D seismic data has been used to optimize sub-surface targets, and underpinned Cairn India’s 2010-11 infill drilling campaign, which was instrumental in arresting the production decline in the field. The infill drilling results, as well as on-going dynamic reservoir surveillance programs are in line with 4D interpretations. All these results are being used to up-date the reservoir model for optimal reservoir management and development. The 4D response in Ravva Field is result of a combination of changes in fluid saturation and pore pressures and hence requires discrete separation of the pressure and saturation components of the 4D effect to enable quantitative interpretation. A 4D simultaneous AVO inversion was carried out using base and monitor datasets to derive the quantifiable elastic property changes in the reservoir. In this paper, we will first discuss the initial 4D interpretation results, the pitfalls of 4D interpretation based on AI – Vp/Vs domain and the importance of pressure and saturation decoupling from the 4D signal in order to identify bypassed oil areas. Next, we will discuss the methodology of decoupling of 4D signal using petro-elastic model and 4D inversion volumes and finally we will show the estimated saturation sections and maps portraying the water flooding signature in the flank side of the structure and undrained areas in the crestal portion.

A 4D seismic survey was carefully planned, executed and interpreted on the Ravva Field. The geoscience and 4D seismic studies have provided key information that defines fault compartments, position of the current OWC and reveals potential undrained areas in field. In this paper, we describe a multidisciplinary approach for the identification of potential areas of bypassed oil. We show examples of how geoscience and engineering disciplines work together and explain the 4D responses which have delineated the areas of the undrained hydrocarbons. The recent infill drilling results along with on-going dynamic reservoir surveillance programs are in line with the 4D interpretations. All these results are being used to up-date the reservoir model for optimal reservoir management and development.