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Previous studies have shown that transcranial direct current stimulation (tDCS) can affect performance by decreasing regional excitability in a brain region that contributes to the task of interest. To our knowledge, no research to date has found both enhancing and diminishing effects on performance, depending upon which polarity of the current is applied. The supramarginal gyrus (SMG) is an ideal brain region for testing tDCS effects because it is easy to identify using the 10-20 electroencephalography coordinate system, and results of neuroimaging studies have implicated the left SMG in short-term memory for phonological and nonphonological sounds. In the present study, we found that applying tDCS to the left SMG affected pitch memory in a manner that depended upon the polarity of stimulation: cathodal tDCS had a negative impact on performance whereas anodal tDCS had a positive impact. These effects were significantly different from sham stimulation, which did not influence performance; they were also specific to the left hemisphere - no effect was found when applying cathodal stimulation to the right SMG - and were unique to pitch memory as opposed to memory for visual shapes. Our results provide further evidence that the left SMG is a nodal point for short-term auditory storage and demonstrate the potential of tDCS to influence cognitive performance and to causally examine hypotheses derived from neuroimaging studies.

Background: Dysphagia is a serious stroke complication but lacks effective therapy. We investigated safety and preliminary efficacy of anodal transcranial direct current stimulation (atDCS) paired with swallowing exercises in improving post-stroke dysphagia from an acute unilateral hemispheric infarction (UHI). Methods: Double-blind, early phase-2 randomized controlled trial, in subjects (n=42) with moderate-severe dysphagia [Penetration and Aspiration Scale (PAS) score ≥ 4], from an acute-subacute UHI. Subjects were randomized to Low-Dose, High-Dose atDCS or Sham stimulation for 5 consecutive days. Primary safety outcomes were incidence of seizures, neurological, motor, or swallowing function deterioration. Primary efficacy outcome was a change in PAS scores at day-5 of intervention. Main secondary outcome was dietary improvement at 1-month, assessed by Functional Oral Intake (FOIS) score.Results: No differences in pre-defined safety outcomes or adjusted mean changes in PAS, FOIS scores, between groups, were observed. Post-hoc analysis demonstrated that 22 /24 subjects in the combined atDCS group had a clinically meaningful dietary improvement (FOIS score ≥ 5) compared to 8 /14 in Sham (p=0.037, Fisher-exact).Conclusion: atDCS application in the acute-subacute stroke phase is safe but did not decrease risk of aspiration in this early phase trial. The observed dietary improvement is promising and merits further investigation.

A survey was conducted in the locality of Uruli Kanchan, Tehsil Haveli, Dist Pune, Maharashtra (Latitude: 18° 29′ 14.7336″. Longitude: 74° 8′ 0.1392) in order to know and document whether the milking bovines are suffering from diseases either currently or in previously in order to know their health status and suggest ways to improve them by the health department. The survey included all milking bovines like cows, buffaloes, and goats that are the majority of the selected locality. These types of bovines had an earlier history of suffering from various diseases like mastitis, ringworm, and anthrax, from which the majority have recovered and are healthy now. This survey includes a personal visit to the owners’ premises, collecting related information directly, and recording the response. The questions asked during the interaction are also attached.

Previous studies have shown that transcranial direct current stimulation (tDCS) can affect performance by decreasing regional excitability in a brain region that contributes to the task of interest. To our knowledge, no research to date has found both enhancing and diminishing effects on performance, depending upon which polarity of current is applied. The supramarginal gyrus (SMG) is an ideal brain region for testing tDCS effects because it is easy to identify using the 10-20 EEG coordinate system, and results of neuroimaging studies have implicated the left SMG in short-term memory for phonological and non-phonological sounds. In the present study, we found that applying tDCS to the left SMG affected pitch memory in a manner that depended upon the polarity of stimulation: cathodal tDCS had a negative impact on performance while anodal tDCS had a positive impact. These effects were significantly different from sham stimulation, which did not influence performance; they were also specific to the left hemisphere – no effect was found when applying cathodal stimulation to the right SMG – and were unique to pitch memory as opposed to memory for visual shapes. Our results provide further evidence that the left SMG is a nodal point for short-term auditory storage and demonstrate the potential of tDCS to influence cognitive performance, and to causally examine hypotheses derived from neuroimaging studies.

Crop losses by plant pests have been a major global concern and hence various techniques have been introduced the control such pests. Pests like stink bugs have known to cause considerable damage to crops. As a result, understanding their taxonomy is crucial, hence DNA based techniques like DNA barcoding have been introduced to augment the identification of stink bugs. A short fragment of mitochondrial Cytochrome c Oxidase subunit I (COI) gene can be used for host-specific identification of the stink bugs. Though this methodology is not fully reliable, the arena is open for research with appropriate changes in current data and hence can help to identify these bugs and probably other similar arthropods. In this review, species identification of stink bugs by assessing COI gene has been described briefly along with statistical methods like neighbor-joining for biomonitoring the pests.

The WHO has recommended ‘frequent hand washing’ as means to curtail the spread of ‘Public Health Emergencies of International Concern.’ Improvement in the seven step hand wash compliance rate has been shown to reduce the spread of hospital acquired infections. Most of the hand hygiene compliance identification systems developed over the years have restricted their focus on tracking the movement of healthcare workers to and from the hand wash station. However, these systems have failed to detect if the seven step hand wash were performed or not. We proposed and implemented a computer vision and artificial intelligence based system to detect seven steps of the hand wash process. We used the Visual Geometry Group-16 (VGG-16) network combined with the Long Short Term Memory (LSTM) module as a classification system. We developed the hand wash database of 3000 videos to train and optimize the parameters of the VGG16-LSTM model. The optimized model detects different steps of handwash with high accuracy and near real time detection ability. This system will prove to be useful for improving hand wash compliance rate and to curb the spread of infectious diseases.

We used three dose levels (Sham, 2 mA, and 4 mA) and two different electrode montages (unihemispheric and bihemispheric) to examine DOSE and MONTAGE effects on regional cerebral blood flow (rCBF) as a surrogate marker of neural activity, and on a finger sequence task, as a surrogate behavioral measure drawing on brain regions targeted by transcranial direct current stimulation (tDCS). We placed the anodal electrode over the right motor region (C4) while the cathodal or return electrode was placed either over a left supraorbital region (unihemispheric montage) or over the left motor region (C3 in the bihemispheric montage). Performance changes in the finger sequence task for both hands (left hand: p = 0.0026, and right hand: p = 0.0002) showed a linear tDCS dose response but no montage effect. rCBF in the right hemispheric perirolandic area increased with dose under the anodal electrode (p = 0.027). In contrast, in the perirolandic ROI in the left hemisphere, rCBF showed a trend to increase with dose (p = 0.053) and a significant effect of montage (p = 0.00004). The bihemispheric montage showed additional rCBF increases in frontomesial regions in the 4mA condition but not in the 2 mA condition. Furthermore, we found strong correlations between simulated current density in the left and right perirolandic region and improvements in the finger sequence task performance (FSP) for the contralateral hand. Our data support not only a strong direct tDCS dose effect for rCBF and FSP as surrogate measures of targeted brain regions but also indirect effects on rCBF in functionally connected regions (e.g., frontomesial regions), particularly in the higher dose condition and on FSP of the ipsilateral hand (to the anodal electrode). At a higher dose and irrespective of polarity, a wider network of sensorimotor regions is positively affected by tDCS.

Identification and differentiation of morphologically similar species have been a significant challenge to taxonomists due to a higher degree of similarity in their physical appearances leading to make the taxonomic investigation more complex. Such a problem is more common in invertebrate soil animals such as earthworms (Eisenia fetida and Eisenia andrei) since their identification requires observation of morphological characters that are very difficult and complex to visualize, especially in the case of sibling or subspecies. In this review, we assessed the utility of mitochondrial cytochrome c oxidase subunit I (COI) gene as a molecular marker for identification and differentiation among these species. We achieved this by analyzing their phylogeny using the neighbor-joining method and Automated Barcode Gap Discovery (ABGD) by retrieving 84 COI sequences from NCBI. As a result, we found that the identification and differentiation success of Eisenia fetida was 96.42%, whereas, for Eisenia andrei, it was 100%. Besides, ABGD analysis suggested that the species failed to give a distinct barcode gap, and the partition pattern may be due to probable misidentification leading to generate discordance among results of ABGD and NJ tree. Finally, we suggest that the multiloci approach of the mitochondrial genome can be used to solve this taxonomic ambiguity making the molecular identification system more reliable and comprehensive fulfilling need of growing biodiversity conservation programs on a global scale.

Controlled illumination at targetted locations (targeted illumination) and imaging at high switching speed have found significant applications in different frontiers of science and technology such as optogenetics, photodynamic therapy (PDT), neurophotonics, and medical imaging. Although there are numerous optical systems reported with targeted illumination ability, most of these are modified standard (bench top) microscopes, hence not suitable for in vivo applications. Therefore, there is a critical need to develop optical imaging systems with targeted illumination suitable for in vivo studies. The small diameter, user-defined length and high mechanical flexibility of fiber optic imaging bundle (FOIB) facilitates its positioning at remote and difficult-toaccess in vivo sites. Recently, few FOIB based studies are reported, which have shown adaptation of targeted illumination. However, image resolution and switching speed achieved with these methods are found to be limited to 10 11m and 20 Hz, respectively. In order to investigate biological or chemical processes, the methodology adopted or equipment used should be able to provide higher resolution, faster-switching speed and an option for targeted illumination and imaging. Moreover, images obtained with FOIB probes are always affected by pixelation noise which deteriorates the image resolution and contrast. Though there are many algorithms to remove pixelation noise, objective comparison of these algorithms are not possible due to the non-availability of a common test image database. Also, there are no theoretical models available currently to simulate the image guidance through FOm. From this perspective, one of the objectives of this thesis is aimed at developing a high-speed imaging probe using a combination of FOffi and Digital Micromirror Device (DMD) with targeted illumination and imaging feature for potential in vivo applications. Compared to the earlier FOffi based probes, the newly developed probe has shown improved lateral and axial image resolution of2.7 Jlm and 5.5 J.Lm, respectively. This imaging system also provides a larger field of view (200 J.Lm X 200 J.Lm) at high resolution compared to earlier reported targeted FOffi probes. The developed FOffi probe's illumination switching speed is defined by the DMD, which is 10,000 Hz. The multiline digitally controlled laser source allows the FOffi probe to illuminate the targeted regions with different wavelengths. Further, an objective comparison of different depixelation methods for FOIB imaging is also performed as part of the investigation. A theoretical model for FOffi based imaging is developed and used to generate images of simulated fiber pixelated 1mages. The parameters such as packing fraction, fiberlet to fiberlet distance, fiberlet core diameter, core-cladding properties and light guiding properties of fiberlet are considered in the theoretical formulations. These studies have led to the development of a Fiber Pixelated Image Database (FPID), which now serves as a free open source common test image sample database for researchers working on the development of novel depixelation methods. The effect of variable pinhole size on the imaging properties is also studied using the proposed probe. An illustrative demonstration is carried out for four different imaging approaches using this targeted FOffi probe. These approaches are 'targeted confocal imaging', 'multi-directional scanning in targeted sample regions', 'targeted time averaged imaging for contrast enhancement', and 'single shot multitarget multispectral imaging', which were found to improve resolution, contrast, and imaging speed. The potential of the FOffi probe is demonstrated by synchronous multispectral spatiotemporal illumination of targeted mouse kidney cells. Additionally, the efficiency of this FOffi probe for tracking and targeted illumination of dynamic (moving) particles is demonstrated as a proof of concept. This developed FOIB probe ·has also been demonstrated as a portable targeted illumination source for the standard bench-top microscope. The second major objective of this thesis is aimed at imaging around opaque obstacles. Since there are numerous injuries (cuts) reported due to blind injection or improper position of the surgical tool, caused due to the blocking of the field of view of the sample by opaque surgical tools during surgery, an imaging system capable of imaging around obstacle would be helpful in avoiding such injuries. Hence in this thesis, a detailed research is carried out to come up with an optical system to image around obstacles. In this thesis, use of an axicon lens is explored for imaging around opaque obstacles. The simulation of axicon lens to perform imaging around an opaque obstacle is demonstrated using Zemax software. This is further validated experimentally by imaging around different thick opaque obstacles of different shape and thickness, such as Allen key, syringe needle, metallic pin, hair, and thread. Finally, the proof of concept of this method is demonstrated by imaging around a surgical needle during needle injection procedure. It is envisaged that the invaluable advantages provided by the targeted probe along with its specialty features can make a great impact in the research and developmental arena such as optogenetics to selectively activate neuronal cells or cell organelles. Further the work done on the imaging round opaque obstacles are expected to contribute significantly during surgical procedures in the near future. Doctor of Philosophy (MAE)

Transcranial direct current stimulation (tDCS) is increasingly being used as a possible tool to enhance plasticity in brain regions that might undergo remodeling after a stroke. Our aim was to determine whether dose and montage of tDCS leads to differential changes in regional cerebral blood flow (rCBF) and differential effect on a finger sequence motor learning experiment. Methods: A total of 20 right-handed healthy subjects participated in 6 imaging and 6 motor learning sessions. Brain images of non-invasive blood flow (using arterial spin labelling) were obtained before (6min), during (10min), as well as after (8min) tDCS was applied within the MRI scanner. For the motor sequence learning experiment as well as for the imaging studies, we used three different dose levels (Sham, 2mA, and 4mA) and two different electrode montages (unihemispheric or bihemispheric). In both montages, the anodal electrode (excitability increasing) was placed over the right motor region (C4) while the cathodal electrode (excitability decreasing) was placed either over a left supraorbital region (unihemispheric montage) or over the left motor region (C3; bihemispheric montage). Imaging data were processed and analyzed using SPM12. For the finger sequence learning task, subjects were asked to type a randomly chosen sequence of 7 items (using numbers 2-5 on a computer keyboard) with digits 2-5 of each hand several times before and immediately after a 10 min stimulation period. Results: After unihemispheric and bihemispheric stimulation, left hand showed more improvement in finger sequence learning than right hand, although a linear trend as a function of dose was observed in both montage conditions. rCBF increased during the Stimulation condition and showed a clear linear effect of dose in the peri-rolandic region. Bihemispheric stimulation showed similar, but stronger effects and revealed additional activation of frontomesial regions in the 4mA condition. Conclusion: tDCS dose has an effect on regional surrogate markers of neuronal/synaptic. Effects in a finger sequence learning showed a similar dose effect. Montage (unihemispheric versus bihemispheric) shows differential brain effects, but based on our preliminary analysis no clear behavioral effects.

SARS-CoV2, the infectious biological entity has made havoc across the globe and created a question mark on the survival of humans. This infectious agent is a variant of SARS-CoV spread in 2003 and more dangerous than previous infectious particles belonging to the same family. Biological objects get a mutation in their genetic makeup which is either beneficial or harmful. If a mutation is useful, the entity is selected by nature for survival. Such genetic changes are continuous processes, and organisms generate their variants. In this review, we have highlighted whether this theory is true regarding SARS-CoV2 or not. We have estimated the probability of reappearance of coronaviridae members in the future with their variant forms.

As the needs of people are increasing, the demand for loans in banks is also frequently getting higher every day. Banks typically process an applicant’s loan after screening and verifying the applicant’s eligibility, which is a difficult and time-consuming process. In some cases, some applicants default and banks lose capital. The machine learning approach is ideal for reducing human effort and effective decision making in the loan approval process by implementing machine learning tools that use classification algorithms to predict eligible loan applicants.

Non-invasive brain-stimulation has been reported to modulate cortical excitability, synaptic plasticity, and interhemispheric interactions of homotop brain regions. All of these processes could play a role in facilitating stroke recovery. Modulation in cortical excitability covaries with changes in regional cerebral blood flow. Our aim was to determine whether varying parameters of transcranially applied direct current stimulation would modulate regional cerebral blood flow and behavioral measures such as motor sequence learning in a differential effect. Twelve right-handed subjects participated in all behavioral and imaging studies. We used three different dose levels (Sham, 2mA and 4mA corresponding current densities: 0mA/cm2, 0.156mA/cm2, and 0.318mA/cm2) and two different electrode montages (unihemispheric or bihemispheric) to examine tDCS effects on a finger sequence learning task and on regional cerebral blood flow (using Arterial Spin Labeling as a Blood Flow MR sequence) using an MR compatible NeuroConn DCMC stimulator. An anodal electrode (diameter of 4 cm) was placed over the right motor region (C4) while the cathodal electrode (diameter of 5 cm) was either placed over the left supraorbital region (unihemispheric montage) or over the left motor region (C3; bihemispheric montage). Each stimulation was of 10 min duration (ON condition) and preceded by 6 minutes of no stimulation and followed by 8 minutes of no stimulation (OFF conditions). A significant difference (p

Breaking the diffraction limit in imaging microscopes with far-field imaging options has always been the thrust challenge for optical engineers and biologists over the years. Although structured illumination microscopy and Bessel beam assisted imaging has shown the capability of imaging with sub-diffraction resolutions, they rely on the use of objective lenses with large numerical apertures (NA). Hence, they fail to sustain resolutions at larger working distances. In this context, we demonstrate a method for nanoscale resolution imaging at longer working distances, named as Structured Illumination Bessel Microscopy (SIBM). The proposed method is envisaged for both biological and engineering applications that necessitate high imaging resolutions at large working distances. EDB (Economic Devt. Board, S’pore) MOE (Min. of Education, S’pore) Published version

Axicon lenses are conical prisms, which are known to focus a light source to a line comprising of multiple points along the optical axis. In this study, we analyze the potential of axicon lenses to view, image and record the object behind opaque obstacles in free space. The advantage of an axicon lens over a regular lens is demonstrated experimentally. Parameters such as obstacle size, object and the obstacle position in the context of imaging behind obstacles are tested using Zemax optical simulation. This proposed concept can be easily adapted to most of the optical imaging methods and microscopy modalities. MOE (Min. of Education, S’pore) Published version

Spatially non-uniform illumination patterns have shown significant potential to improve the imaging. Recent developments in the patterned illumination microscopy have demonstrated that the use of an optical speckle as an illumination pattern significantly improves the imaging resolution at the same time reducing the computational overheads. We present a DMD based method for generation of digital speckle pattern. The generated digital speckle and uniform white light illumination are used as two illuminations to acquire images. The image reconstruction algorithm for blind structured illumination microscopy is used to get the high resolution image. Our approach does not require any calibration step or stringent control of the illumination, and dramatically simplifies the experimental set-up.

An optical imaging probe with targeted multispectral and spatiotemporal illumination features has applications in many diagnostic biomedical studies. However, these systems are mostly adapted in conventional microscopes, limiting their use for in vitro applications. We present a variable resolution imaging probe using a digital micromirror device (DMD) with an achievable maximum lateral resolution of 2.7 μm and an axial resolution of 5.5 μm, along with precise shape selective targeted illumination ability. We have demonstrated switching of different wavelengths to image multiple regions in the field of view. Moreover, the targeted illumination feature allows enhanced image contrast by time averaged imaging of selected regions with different optical exposure. The region specific multidirectional scanning feature of this probe has facilitated high speed targeted confocal imaging.

Time averaged imaging is one of the widely used methods to achieve improved image quality, used in different types of microscopic methods. Time averaged imaging refers to adjusting the exposure time of the imaging system to obtain optimal images. In state of the art microscopes, the region of interest (ROI) of illumination beam for time averaged imaging can be selected to be of regular shapes such as circle or rectangle. This forces smallest possible ROI to be larger than the actual sample’s ROI which can be of a specific shape with complex contours. In this context, we present a flexible fiber bundle based illumination probe capable of illuminating samples of irregular shapes for time averaged imaging. Further, this probe is capable of multi-wavelength illumination, hence can be used for multi-fluorescence imaging. The fiber probe with features such as region selective and multi- wavelength illumination allows it to be used for optimal imaging of multi-fluorescence sample. MOE (Min. of Education, S’pore) Published version

It is well known for structured illumination microscopy (SIM) that the lateral resolution by a factor of two beyond the classical diffraction limit is achieved using spatially structured illumination in wide-field fluorescence microscope. In the state of art SIM systems, grating patterns are generally generated by physical gratings or by spatial light modulators such as digital micro mirrors (DMD), liquid crystal displays (LCD). In this study, using a combination of LCD and ground glasses, size controlled randomized speckle patterns are generated as an illumination source for the microscope. Proof of concept of using speckle illumination in SIM configuration is tested by imaging fixed BPAE cells. MOE (Min. of Education, S’pore) Published version

Flexible and thin endoscopy procedures have become an indispensible tool in medical diagnostics in the recent past. However, the demands for reduced probe diameter as well as enhanced spatial resolution have not yet met the forecasted target by the clinical practitioners. There has been renewed interest in using image fiber bundle as it can offer variable resolution by exciting the chosen fiberlet groups using spatial modulator in the analog or digital form. However, the image-guiding media accompany the degradation in spatial resolution due to the fiberlet boundaries. This paper overviews different image processing protocols that can be integrated with such an image fiber based probe endoscopic system for removing the pixelate appearance from the image. Comb structure removal approaches such as spatial averaging filters, spectral filters and interpolation methods are integrated with the imaging protocol and a comparative analysis is presented in this paper. As a proof-of-concept analysis, we have eliminated the pixelation artifacts and illustrated by imaging United States Air Force (USAF) resolution test chart and neuroblastoma cells as test samples.

We report a simple real time optical imaging concept using an axicon lens to image the object kept behind opaque obstacles in free space. The proposed concept underlines the importance and advantages of using an axicon lens compared to a conventional lens to image behind the obstacle. The potential of this imaging concept is demonstrated by imaging the insertion of surgical needle in biological specimen in real time, without blocking the field of view. It is envisaged that this proposed concepts and methodology can make a telling impact in a wide variety of areas especially for diagnostics, therapeutics and microscopy applications.

Direct visualization and assessment of the iridocorneal angle (ICA) region with high resolution is important for the clinical evaluation of glaucoma. However, the current clinical imaging systems for ICA do not provide sufficient structural details due to their poor resolution. The key challenges in achieving high quality ICA imaging are its location in the anterior region of the eye and the occurrence of total internal reflection due to refractive index difference between cornea and air. Here, we report an indirect axicon assisted gonioscopy imaging probe with white light illumination. The illustrated results with this probe shows significantly improved visualization of structures in the ICA including TM region, compared to the current available tools. It could reveal critical details of ICA and expected to aid management by providing information that is complementary to angle photography and gonioscopy.

There was a renewed interest, during the recent years, in the imaging and tracking of targeted cells or organelles for a variety of biomedical and lab-on a chip applications that include particles movement. However, nonspecific illumination during tracking can have adverse effects such as heating, reduced image contrast and photo bleaching. In fact, current available tracking and imaging systems are unable to selectively illuminate the particle being tracked. To fill this void, we have developed a fiber optics based probe system incorporating a spatial light modulator (SLM) and an imaging fiber bundle for selective illumination on the targeted particle. A GRIN lens is attached at the distal endface of the image fiber bundle for optimised illumination and collection. A tracking algorithm is developed in order to enable controlled illumination through SLM to target the illumination point or location in accordance with the particle movement and size variation. Further with this probe, particles can be illuminated with light pulses of controllable duty cycle and frequency. The proposed methodology and developed probe have good significance and expected to find potential applications areas such as optogenetics, cell signalling studies, and lab-on a chip systems.

Flexible fiber optic imaging systems including fiber optic confocal probes have found tremendous significance in the recent past for its applications in high resolution imaging. However, motorized stage is required for scanning the sample or tip of the fiber in fiber based confocal probes. In this context, we propose a fiber probe confocal system using digital spatial light modulator devoid of using a mechanical scanning stage. Each fiberlet in the image fiber acts not only as a light conduit but also as a confocal pinhole. The paper also introduces the variation in the contrast by varying the number of illuminated fiberlets which effectively implies variation in the effective pinhole size. This approach has enabled the probe to act as an imaging unit with resolution that can be controlled and varied from a wide-field to a confocal. Published version

Visual access to physically inaccessible parts has become the forefront of research and development in medical diagnostics tools and procedures. Flexible and thin endoscopes with fiber bundle as an image conduit serves this purpose. However, when the light passes through the core of the fiberlet, it is blocked by the inter fiberlet gap. This structural limitation creates special honeycomb like pattern overlaying the image captured with the image fiber assisted probes, known as the comb structure or fiber pixelation. It obstructs the perception of the original image sacrificing resolution and contrast and inhibits the use of object recognition and tracking algorithms. Generally, comb structure removal or depixelation methods are employed to remove honeycomb pattern from an image. In the recent past, several depixelation techniques have been proposed albeit using different set of pixilated images by different researchers. It is quite difficult to make a comparison of their performances based on such images, as they adopt different images for different particular framework of their study. In this context, a basic database of such images is the need of the hour to meet the growing diagnostic needs in the medical and industrial arena. This paper in this context proposes and details a Comb Structure Affected Image database (CSAI) to meet the objective. Images are generated considering the image fiber specifications and the characteristics at different targeted optical imaging modalities delineated by resolution scales. The proposed database is designed to have a set of synthetically generated pixelated images of test patterns of different scales, sizes and shapes. Published version

We report a simple real time optical imaging concept using an axicon lens to image the object kept behind opaque obstacles in free space. The proposed concept underlines the importance and advantages of using an axicon lens compared to a conventional lens to image behind the obstacle. The potential of this imaging concept is demonstrated by imaging the insertion of surgical needle in biological specimen in real time, without blocking the field of view. It is envisaged that this proposed concepts and methodology can make a telling impact in a wide variety of areas especially for diagnostics, therapeutics and microscopy applications.