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1.
Heliyon ; 10(11): e31551, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38828321

ABSTRACT

Storage pests, particularly bruchids, are major biotic constraints causing significant storage losses in pulses. Conventional control methods relying on insecticides and fumigants often lead to food contamination due to toxic pesticide residues and a rapid decline in seed germination. In this investigation, through green nano-technological application, a promising and sustainable alternative for pest management is developed. Silver and copper nanoparticles were synthesized through ocimum leaf extract. The characterization of silver and copper nanoparticles was carried out by UV-spectroscopy, particle size analyzer, scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared. Both the nanoparticles were spherical and crystalline in nature. Greengram seeds were primed with standardized silver and copper nanoparticles at different concentrations (1000, 1500, and 2000 ppm) and compared with castor-treated, deltamethrin-treated, and untreated control seeds for seed quality, growth, and yield. After one month of storage, all the pulse beetles released in different treatments exhibited 100 % mortality, whereas in control, the insects multiplied. At the end of nine months, the control seeds had shown 72 % damage and 39.67 % germination. In contrast, silver nanoparticles at 1000 ppm showed no seed damage and achieved 81.67 % germination, which was on par with copper nanoparticles at 1000 ppm with 79.33 % germination. Seed priming of silver and copper nanoparticles at 1000 ppm also demonstrated superior performance in all the seed quality and biochemical parameters (alpha amylase and catalase) throughout the storage period. Whereas, in the greenhouse experiment, enhanced growth (35.96 cm, 46.48 cm, and 53.00 cm at 30, 60 DAS, and at harvest, respectively) and yield per plant (3.75 g) were significantly higher in plants that were given foliar application with silver nanoparticles at 1000 ppm. Furthermore, foliar application of these nanoparticles at all concentrations (1000, 1500, and 2000 ppm) did not exhibit any adverse effects on soil microbial organisms, as assessed by dehydrogenase enzyme activity. Hence, this research highlights the potential use of silver and copper nanoparticles at 1000 ppm as effective tools for storage pest management and contributing to improved agricultural productivity and sustainability.

2.
J Family Med Prim Care ; 12(10): 2223-2229, 2023 Oct.
Article in English | MEDLINE | ID: mdl-38074269

ABSTRACT

Introduction: The drugs approved by the Food and Drug Administration (FDA) in 2022, for the first time for any indication or under any brand, were studied under the contexts of indications, mechanism of action, and side effects. Primary care practitioners with considering patients as a composite whole will benefit by acquainting themselves with these drugs and their indications and adverse effects. Observations: The drugs were approved in all, 11 for the management of neoplasia, and 5 each for hematological, neurological, and dermatological conditions. 11 of the approved drugs are monoclonal antibodies and six are small molecule inhibitors. Conclusion: Although the FDA's expedited approval program allows rapid market availability of drugs for difficult to treat conditions, a quarter of the globe does not have access to essential medicines, primarily due to cost. In light of this, approval agencies must reorient approval processes to improve accessibility.

3.
Neurotox Res ; 41(6): 698-707, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37847429

ABSTRACT

Alzheimer's disease contributes to 60-70% of all dementia cases in the general population. Belonging to the BIN1/amphiphysin/RVS167 (BAR) superfamily, the bridging integrator (BIN1) has been identified to impact two major pathological hallmarks in Alzheimer's disease (AD), i.e., amyloid beta (Aß) and tau accumulation. Aß accumulation is found to increase by BIN1 knockdown in cortical neurons in late-onset AD, due to BACE1 accumulation at enlarged early endosomes. Two BIN1 mutants, KR and PL, were identified to exhibit Aß accumulation. Furthermore, BIN1 deficiency by BIN1-related polymorphisms impairs the interaction with tau, thus elevating tau phosphorylation, altering synapse structure and tau function. Even though the precise role of BIN1 in the neuronal tissue needs further investigation, the authors aim to throw light on the potential of BIN1 and unfold its implications on tau and Aß pathology, to aid AD researchers across the globe to examine BIN1, as an appropriate target gene for disease management.


Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/genetics , Alzheimer Disease/pathology , Amyloid beta-Peptides/metabolism , Amyloid Precursor Protein Secretases/metabolism , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Aspartic Acid Endopeptidases/metabolism , tau Proteins/metabolism , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism
4.
Pol J Radiol ; 87: e79-e86, 2022.
Article in English | MEDLINE | ID: mdl-35280950

ABSTRACT

Purpose: Tuberculosis is quite common in India. About 40% of all Indians are infected with mycobacterium tuberculosis, with 2.5 million active tuberculosis cases. Tuberculosis primarily affects the lungs, but it can affect any organ. Extra-pulmonary involvement occurs 15-20% of cases in immune-competent patients and in more than 50% in HIV patients. The most common extra-pulmonary sites are lymph nodes, pleura, abdomen, genitourinary tract, skin, joints and bones, or meninges. Case reports: In this pictorial review article we present 8 atypical cases of tuberculosis and describe their imaging features and histopathology. Conclusions: Extra-pulmonary tuberculosis can affect virtually any organ and can mimic various inflammatory and neoplastic disorders apart from other infective conditions. A strong index of suspicion is required particularly in those countries endemic to tuberculosis.

5.
Appl Opt ; 59(24): 7321-7329, 2020 Aug 20.
Article in English | MEDLINE | ID: mdl-32902497

ABSTRACT

Lensless, interferenceless coded aperture correlation holography (LI-COACH) is an incoherent computational optical technique for three-dimensional (3D) imaging. In direct imaging, the image of the object is generated by a lens, whereas the LI-COACH is an indirect imaging technique that consists of two steps: one-time point spread hologram (PSH) training and then many times imaging of multiple-point objects. In the one-time training step, a point object moves in the object space along the optical axis. Light emitted from the point is modulated by a quasi-random phase mask, and the PSH library is recorded. In the imaging step, an object is mounted within the axial boundaries of the PSH library, and the object holograms are recorded using the same quasi-random phase masks. The 3D image of the object is reconstructed by the cross correlation of the object holograms with the PSH library. In this study, the entire PSH library is digitally synthesized from a single PSH, recorded at one plane only. The recorded PSH is scaled by magnification factors corresponding to the various axial planes. The reconstruction results from the synthetic PSH library are comparable with those from the recorded PSH library. The proposed approach can reduce the time of the training step in LI-COACH.

6.
Sci Rep ; 9(1): 17670, 2019 Nov 27.
Article in English | MEDLINE | ID: mdl-31776392

ABSTRACT

We propose and demonstrate a new imaging technique to noninvasively see through scattering layers with the aid of a spatial light modulator (SLM). A relay system projects the incoherent light pattern emitting from the scattering layer onto the SLM. Two coded phase masks are displayed, one after another, on the SLM to modulate the projected scattered field and the two corresponding intensity patterns are recorded by a digital camera. The above procedure helps to achieve two goals. Firstly, since the coded phase masks are digitally synthesized, the point spread function of the imaging system can be engineered such that the image retrieval becomes more reliable. Secondly, the two recorded intensity patterns are subtracted one from the other and by that the background noise of the recovered image is minimized. The above two advantages along with a modified phase retrieval algorithm enable a relatively easier and accurate convergence to the image of the covered object.

7.
Appl Opt ; 58(22): 5982-5988, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31503916

ABSTRACT

A speckle-correlation-based optical lever (SC-OptLev) is constructed for the measurement of small changes in the orientation angle of a surface. The dynamic range of SC-OptLev is found to be twice that of a conventional OptLev for the same experimental configurations. Different filtering mechanisms are implemented, and the correlation results are compared. Two types of computer-automated SC-OptLevs, an open-source-based computing system with a low-cost image sensor and a commercial computing system, are presented with assistive computational modules.

8.
Opt Lett ; 44(7): 1572-1575, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-30933093

ABSTRACT

We present a superresolution technique for imaging objects beyond the diffraction limit imposed by the limited numerical aperture (NA) of a general optical system. A coded phase mask (CPM) displayed on a spatial light modulator is introduced between the object and the input aperture of an ordinary lens-based imaging system. Consequently, the effective NA is increased beyond the inherent NA of the optical imaging system. Unlike conventional systems, the imaging in our proposed method is not direct from an object to a sensor, and the system requires a one-time calibration. In the calibration mode, a point object is mounted in the object plane, and the point spread intensity pattern is recorded. Following the calibration, the system is ready for imaging an arbitrary number of 2D objects. The intensity pattern from any object placed at the same axial location of the point object, and modulated by the same CPM, is recorded once by a digital camera. The superresolved image of the object is reconstructed by a nonlinear cross-correlation between the abovementioned two intensity patterns. The effective NA and the new resolution limit can be tuned by changing the scattering degree of the CPM.

9.
Opt Express ; 27(5): 6459-6470, 2019 Mar 04.
Article in English | MEDLINE | ID: mdl-30876231

ABSTRACT

Structured light has been created by a myriad of near-and far-field techniques and has found both classical and quantum applications. In the case of orbital angular momentum (OAM), continuous spiral phase patterns in dynamic or geometric phase are often employed with the phase patterns existing across the entire transverse plane. Here, we exploit the uncertain relationship between OAM and angle in order to create structured OAM fields by using multilevel OAM holograms. We show theoretically and experimentally that only a multilevel angular phase contour in the near-field is needed to create structured OAM light in the far-field, exploiting the reciprocal nature of angular momentum and angle. We use this approach to demonstrate exotic 3D structured light control to show the Poynting vector's evolution in such fields and to highlight the physics underlying this phenomenon.

10.
Opt Express ; 27(2): 391-403, 2019 Jan 21.
Article in English | MEDLINE | ID: mdl-30696126

ABSTRACT

Interferenceless coded aperture correlation holography (I-COACH) is a non-scanning, motionless, incoherent digital holography technique for 3D imaging. The lateral and axial resolutions of I-COACH are equivalent to those of conventional direct imaging with the same numerical aperture. The main component of I-COACH is a coded phase mask (CPM) used as the system aperture. In this study, the CPM has been engineered using a modified Gerchberg-Saxton algorithm to generate a random distribution of subdiffraction spot arrays on the digital camera as a system response to a point source illumination. A library of point object holograms is created to calibrate the system for imaging different lateral sections of a 3D object. An object is placed within the calibrated 3D space and an object hologram is recorded with the same CPM. The various planes of the object are reconstructed by a non-linear cross-correlation between the object hologram and the point object hologram library. A lateral resolution enhancement of about 25% was noted in the case of I-COACH compared to direct imaging.

11.
Opt Express ; 26(14): 18143-18154, 2018 Jul 09.
Article in English | MEDLINE | ID: mdl-30114094

ABSTRACT

Interferenceless coded aperture correlation holography (I-COACH) is an incoherent digital holography technique for imaging 3D objects without two-wave interference. In I-COACH, the object beam is modulated by a pseudorandom coded phase mask (CPM) and propagates to the camera where its intensity pattern is recorded. The image of the object is reconstructed by a cross-correlation of the object intensity pattern with a point intensity response of the system, whereas the light from both the object and the point, are modulated by the same CPM. In order to recover the image of the object without bias level and background noise, multiple intensity recordings are necessary for both objects as well as the point object, which in turn significantly reduces the time resolution of imaging. In this study, a non-linear reconstruction technique is developed to reconstruct the image of the object with only a single camera shot. Furthermore, the proposed technique is adaptive to different experimental conditions in the sense of finding different optimal parameters for each experiment. The new method has been implemented on a regular I-COACH system in both transmission as well as reflection illumination modes.

12.
Indian J Radiol Imaging ; 28(1): 85-92, 2018.
Article in English | MEDLINE | ID: mdl-29692534

ABSTRACT

There are a number of common pain disorders that can be managed effectively by injections around or ablation of peripheral nerves. Ultrasound is a universally available imaging tool, is safe, cost-effective, and is excellent in imaging many peripheral nerves and guiding needles to the site of the nerves. This article aims to present an overview of indications and techniques of such procedures that can be effectively performed by a radiologist.

13.
Opt Lett ; 43(5): 1043-1046, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29489776

ABSTRACT

Interferenceless coded aperture correlation holography (I-COACH) is an incoherent digital holography technique developed to record and reconstruct 3D images of objects without two-wave interference. Herein, we introduce a novel technique to extend the field of view (FOV) of I-COACH beyond the limit imposed by the ratio between the finite area of the image sensor and the magnification of the optical system. Light diffracted from a point object located on the optical axis is modulated by a pseudorandom coded phase mask, and the central part of the point spread hologram (PSH) on the image sensor is recorded. The point object is shifted laterally to predetermined lateral locations in order to collect the exterior parts of the PSH. The recorded PSHs are stitched together to produce a synthetic PSH (SPSH) with an area nine times that of any individual PSH recorded by the image sensor. An object with a lateral extent beyond the FOV limit of the image sensor is placed at the same axial location as the point object, and the object hologram is recorded. The object is reconstructed by a cross-correlation between the zero-padded object hologram and the SPSH. Hence, the object parts beyond the FOV limit of the image sensor are recovered. An SPSH library is created for different axial planes, and the corresponding axial planes of the object are reconstructed.

14.
Indian J Tuberc ; 65(2): 118-123, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29579424

ABSTRACT

BACKGROUND: Cycloserine (CYC) is a second line antitubercular drug that is used for the treatment of multidrug resistant tuberculosis (MDR-TB) along with other antitubercular agents and is often used in developing countries. Monitoring CYC levels in plasma could be useful in the clinical management of patients with MDR-TB. A high performance liquid chromatography method for the determination of CYC in human plasma was developed. METHODS: The method involved extraction of the sample using solid phase extraction cartridges and analysis of the extracted sample using a reverse phase T3 column (150mm) and detection at 240nm with Photo Diode Array (PDA) detector. The chromatogram was run for 15min at a flow rate of 0.4ml/min at 30°C. RESULTS AND CONCLUSION: The assay was specific for CYC and linear from 5.0 to 50.0µg/ml. The relative standard deviations of within- and between-day assays were less than 10%. Recovery of CYC ranged from 102% to 109%. The interference of other second line anti-TB drugs in the assay of CYC was ruled out. The assay spans the concentration range of clinical interest. The specificity and sensitivity of this assay makes it highly suitable for pharmacokinetic studies.


Subject(s)
Antitubercular Agents/therapeutic use , Chromatography, High Pressure Liquid , Cycloserine/therapeutic use , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Pulmonary/drug therapy , Antitubercular Agents/blood , Cycloserine/blood , Humans , Reproducibility of Results , Sensitivity and Specificity , Tuberculosis, Multidrug-Resistant/blood , Tuberculosis, Pulmonary/blood
15.
Sci Rep ; 8(1): 1134, 2018 01 18.
Article in English | MEDLINE | ID: mdl-29348514

ABSTRACT

Imaging through a scattering medium is a challenging task. We propose and demonstrate an interferenceless incoherent opto-digital technique for 3D imaging through a scatterer with a single lens and a digital camera. The light diffracted from a point object is modulated by a scattering mask. The modulated wavefront is projected on an image sensor using a spherical lens and the impulse response is recorded. An object is placed at the same axial location as the point object and another intensity pattern is recorded with identical experimental conditions and with the same scattering mask. The image of the object is reconstructed by a cross-correlation between a reconstructing function and the object hologram. For 3D imaging, a library of reconstructing functions are created corresponding to different axial locations. The different planes of the object are reconstructed by a cross-correlation of the object hologram with the corresponding reconstructing functions.

16.
Sci Rep ; 7(1): 11555, 2017 09 14.
Article in English | MEDLINE | ID: mdl-28912489

ABSTRACT

We present a lensless, interferenceless incoherent digital holography technique based on the principle of coded aperture correlation holography. The acquired digital hologram by this technique contains a three-dimensional image of some observed scene. Light diffracted by a point object (pinhole) is modulated using a random-like coded phase mask (CPM) and the intensity pattern is recorded and composed as a point spread hologram (PSH). A library of PSHs is created using the same CPM by moving the pinhole to all possible axial locations. Intensity diffracted through the same CPM from an object placed within the axial limits of the PSH library is recorded by a digital camera. The recorded intensity this time is composed as the object hologram. The image of the object at any axial plane is reconstructed by cross-correlating the object hologram with the corresponding component of the PSH library. The reconstruction noise attached to the image is suppressed by various methods. The reconstruction results of multiplane and thick objects by this technique are compared with regular lens-based imaging.

17.
Opt Lett ; 42(19): 3992-3995, 2017 Oct 01.
Article in English | MEDLINE | ID: mdl-28957180

ABSTRACT

We propose a new scheme for recording an incoherent digital hologram by a single camera shot. The method is based on a motionless, interferenceless, coded aperture correlation holography for 3D imaging. Two random-like coded phase masks (CPMs) are synthesized using the Gerchberg-Saxton algorithm with two different initial random phase profiles. The two CPMs are displayed side by side and used as the system aperture. Light from a pinhole is introduced into the system, and two impulse responses are recorded corresponding to the two CPMs. The two impulse responses are subtracted, and the resulting intensity profile is used as a reconstructing hologram. A library of reconstructing holograms is created corresponding to all possible axial locations. Following the above training stage, an object is placed within the axial limits of the library, and the intensity patterns of a single shot, corresponding to the same two CPMs, are recorded under identical conditions to generate the object hologram. The image of the object at any plane is reconstructed by a cross-correlation between the object hologram and the corresponding reconstructing hologram from the library.

18.
Opt Express ; 25(12): 13883-13896, 2017 Jun 12.
Article in English | MEDLINE | ID: mdl-28788831

ABSTRACT

Recording digital holograms without wave interference simplifies the optical systems, increases their power efficiency and avoids complicated aligning procedures. We propose and demonstrate a new technique of digital hologram acquisition without two-wave interference. Incoherent light emitted from an object propagates through a random-like coded phase mask and recorded directly without interference by a digital camera. In the training stage of the system, a point spread hologram (PSH) is first recorded by modulating the light diffracted from a point object by the coded phase masks. At least two different masks should be used to record two different intensity distributions at all possible axial locations. The various recorded patterns at every axial location are superposed in the computer to obtain a complex valued PSH library cataloged to its axial location. Following the training stage, an object is placed within the axial boundaries of the PSH library and the light diffracted from the object is once again modulated by the same phase masks. The intensity patterns are recorded and superposed exactly as the PSH to yield a complex hologram of the object. The object information at any particular plane is reconstructed by a cross-correlation between the complex valued hologram and the appropriate element of the PSH library. The characteristics and the performance of the proposed system were compared with an equivalent regular imaging system.

19.
Appl Opt ; 56(13): F67-F77, 2017 May 01.
Article in English | MEDLINE | ID: mdl-28463243

ABSTRACT

Coded aperture correlation holography (COACH) is a recently introduced technique for recording incoherent digital holograms of general three-dimensional scenes. In COACH, a random-like coded phase mask (CPM) is used as a coded aperture. Even though the CPM is optimized to reduce background noise, there is still a substantial amount of noise, mitigating the performance of COACH. In order to reduce the noise, we first modify the hologram reconstruction method. Instead of computing the correlation between a complex hologram of the entire object and a hologram of a source point, in this study the numerical correlation is performed with a phase-only filter. In other words, the phase function of the Fourier transform of the source point hologram is used as the spatial filter in the correlation process. Furthermore, we propose and demonstrate two additional methods for reducing the background noise in COACH. The first is based on the integration of a quadratic phase function, as used in Fresnel incoherent correlation holography (FINCH), with the CPM of COACH. This hybrid COACH-FINCH system enables a dynamic trade-off between the amount of background noise and the axial resolution of the system. The second method is employed by recording COACH holograms with multiple independent CPMs and averaging over the reconstructed images. The results of the above two techniques are compared with FINCH and with a regular imaging system.

20.
Appl Opt ; 56(13): F128-F133, 2017 May 01.
Article in English | MEDLINE | ID: mdl-28463306

ABSTRACT

In this study, we introduce what we believe is a novel holographic optical element called a chiral square Fresnel zone plate (CSFZP). The chirality is imposed on a square Fresnel zone plate (SFZP) using a nonclassical technique by rotating the half-period zones relative to one another. The rotation of the half-period zones, in turn, twists the side lobes of the diffraction pattern without altering the focusing properties inherent to a SFZP. As a consequence, the beam profile is hybrid, consisting of a strong central Gaussian focal spot with gradient force similar to that generated by a lens and twisted side lobes with orbital angular momentum. The optical fields at the focal plane were calculated and found to possess a whirlpool-phase profile and a twisted intensity profile. Analysis of the field variation along the direction of propagation revealed a spiraling phase and amplitude distribution. Poynting vector plot of the fields revealed the presence of angular momentum in the regions of chiral side lobes. The phase of the CSFZPs were displayed on a phase-only reflective spatial light modulator and illuminated using a laser. The intensity patterns recorded in the experiment match the calculated ones, with a strong central focal spot and twisted side lobes. The beam pattern was implemented in an optical trapping experiment and was found to possess particle trapping capabilities.

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