scholarly journals A simple cost-effective infra-red microscope for palynology

1995 ◽  
Vol 14 (2) ◽  
pp. 106-106 ◽  
Author(s):  
J. E. A. Marshall

Abstract. It has long been known that objects which are opaque in transmitted white light can become translucent in infra-red (IR) light. Its application to palynology was shown by Leclercq (1933) who used an IR filter to cut out the visible light from the specimen coupled with an IR-sensitive film to capture the image. Although the significance of this development was recognized (Walton, 1935), it was never generally used since oxidative methods such as Schulze’s solution are normally successful in clearing exines. The exceptions are opaque palynomorphs from thermally over-mature rocks. Such assemblages have been studied with IR microscopy using either IR-sensitive film on partially cleared material (e.g. Tiwari & Schaarschmidt, 1975) or electronic IR imaging systems (Cramer & Diez, 1972).The technical sophistication and performance of IR imaging microscopes has recently improved significantly following their routine application for the internal imaging of silicon chips. However, such microscopes are designed for use in reflected light and also rather costly. In addition their design makes them difficult to routinely switch from brightfield transmitted light to IR light without risk of damaging their sensitive IR tube. This note describes a simplified IR microscope for transmitted light which shows how excellent images of opaque spores in the near-IR can be produced using the simplest palynological microscope.This IR microscope is based around an Olympus BHSM-IR system. This is fitted with a 100W quartz halogen bulb which is essential for providing the required level of IR illumination. However, the only specific IR corrected optics this. . .

2020 ◽  
Vol 117 (7) ◽  
pp. 3388-3396 ◽  
Author(s):  
Martin Schnell ◽  
Shachi Mittal ◽  
Kianoush Falahkheirkhah ◽  
Anirudh Mittal ◽  
Kevin Yeh ◽  
...  

Optical microscopy for biomedical samples requires expertise in staining to visualize structure and composition. Midinfrared (mid-IR) spectroscopic imaging offers label-free molecular recording and virtual staining by probing fundamental vibrational modes of molecular components. This quantitative signal can be combined with machine learning to enable microscopy in diverse fields from cancer diagnoses to forensics. However, absorption of IR light by common optical imaging components makes mid-IR light incompatible with modern optical microscopy and almost all biomedical research and clinical workflows. Here we conceptualize an IR-optical hybrid (IR-OH) approach that sensitively measures molecular composition based on an optical microscope with wide-field interferometric detection of absorption-induced sample expansion. We demonstrate that IR-OH exceeds state-of-the-art IR microscopy in coverage (10-fold), spatial resolution (fourfold), and spectral consistency (by mitigating the effects of scattering). The combined impact of these advances allows full slide infrared absorption images of unstained breast tissue sections on a visible microscope platform. We further show that automated histopathologic segmentation and generation of computationally stained (stainless) images is possible, resolving morphological features in both color and spatial detail comparable to current pathology protocols but without stains or human interpretation. IR-OH is compatible with clinical and research pathology practice and could make for a cost-effective alternative to conventional stain-based protocols for stainless, all-digital pathology.


Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1437
Author(s):  
Jing Yi Ong ◽  
Andrew Pike ◽  
Ling Ling Tan

The presence of mycotoxins in foodstuffs and feedstuffs is a serious concern for human health. The detection of mycotoxins is therefore necessary as a preventive action to avoid the harmful contamination of foodstuffs and animal feed. In comparison with the considerable expense of treating contaminated foodstuffs, early detection is a cost-effective way to ensure food safety. The high affinity of bio-recognition molecules to mycotoxins has led to the development of affinity columns for sample pre-treatment and the development of biosensors for the quantitative analysis of mycotoxins. Aptamers are a very attractive class of biological receptors that are currently in great demand for the development of new biosensors. In this review, the improvement in the materials and methodology, and the working principles and performance of both conventional and recently developed methods are discussed. The key features and applications of the fundamental recognition elements, such as antibodies and aptamers are addressed. Recent advances in aptasensors that are based on different electrochemical (EC) transducers are reviewed in detail, especially from the perspective of the diagnostic mechanism; in addition, a brief introduction of some commercially available mycotoxin detection kits is provided.


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1342
Author(s):  
Borja Nogales ◽  
Miguel Silva ◽  
Ivan Vidal ◽  
Miguel Luís ◽  
Francisco Valera ◽  
...  

5G communications have become an enabler for the creation of new and more complex networking scenarios, bringing together different vertical ecosystems. Such behavior has been fostered by the network function virtualization (NFV) concept, where the orchestration and virtualization capabilities allow the possibility of dynamically supplying network resources according to its needs. Nevertheless, the integration and performance of heterogeneous network environments, each one supported by a different provider, and with specific characteristics and requirements, in a single NFV framework is not straightforward. In this work we propose an NFV-based framework capable of supporting the flexible, cost-effective deployment of vertical services, through the integration of two distinguished mobile environments and their networks: small sized unmanned aerial vehicles (SUAVs), supporting a flying ad hoc network (FANET) and vehicles, promoting a vehicular ad hoc network (VANET). In this context, a use case involving the public safety vertical will be used as an illustrative example to showcase the potential of this framework. This work also includes the technical implementation details of the framework proposed, allowing to analyse and discuss the delays on the network services deployment process. The results show that the deployment times can be significantly reduced through a distributed VNF configuration function based on the publish–subscribe model.


Author(s):  
Kala Meah ◽  
Steven Fletcher ◽  
Yu Wan ◽  
Sadrul Ula

Many parts of the western US is rural in nature and consequently do not have electrical distribution lines in many parts of farms and ranches. Distribution line extension costs can run from $15,000 to $25,000 per mile, thereby making availability of electricity to small water pumping projects economically unattractive. Solar photo-voltaic (PV) powered water pumping is more cost effective in these small scale applications. Many western states including Wyoming are passing through fifth year of drought with the consequent shortages of water for many applications. Wyoming State Climatologist is predicting a possible 5–10 years of drought. Drought impacts the surface water right away, while it takes much longer to impact the underground aquifers. To mitigate the effect on the livestock and wildlife, Wyoming Governor Dave Freudenthal initiated a solar water pumping initiative in cooperation with the University of Wyoming, County Conservation Districts, Rural Electric Cooperatives, and ranching organizations. Solar water pumping has several advantages over traditional systems; for example, diesel or propane engines require not only expensive fuels, they also create noise and air pollution in many remote pristine areas. Solar systems are environment friendly, low maintenance and have no fuel cost. In this paper the design, installation and performance monitoring of the solar system for small scale remote water pumping will be presented.


Author(s):  
Will Judge ◽  
Georges Kipouros

The production of aluminum alloys through powder metallurgy (PM) processes allows for the manufacture of net- or near-net-shape components in a cost-effective and sustainable manner. The high reactivity of aluminum metal, however, complicates PM processing, and special attention must be given to certain steps during production, particularly sintering. PM processing conditions strongly affect the structure and porosity of aluminum PM alloys, which ultimately determine their material properties and performance. In this article, the fundamental aspects of the commercial production of aluminum PM alloys are presented, along with the effects of production conditions on the structure and porosity of aluminum PM alloys. The properties and performance of aluminum PM alloys are then analyzed and interpreted with respect to their structure and porosity.


Stroke ◽  
2016 ◽  
Vol 47 (suppl_1) ◽  
Author(s):  
Olli S Mattila ◽  
Heini Harve ◽  
Saana Pihlasviita ◽  
Juhani Ritvonen ◽  
Gerli Sibolt ◽  
...  

Background and purpose: Blood-based biomarkers could enable early and cost-effective diagnostics for acute stroke patients in the prehospital setting to support early initiation of treatments. However, large prehospital sample sets required for biomarker discovery and validation are missing, and the feasibility of large-scale blood sampling by emergency medical services (EMS) has not been determined. We set out to establish extensive prehospital blood sampling of thrombolysis candidates in the catchment area of our comprehensive stroke center, with a 1.5 million population base. Methods: EMS personnel were trained to collect prehospital blood samples using a cannula-adapter technique. Time delays, sample quality and performance bottlenecks were investigated between May 20, 2013 and May 19, 2014. Results: Prehospital blood sampling and study recruitment were successfully performed in 430 thrombolysis candidates, of which 55.3% were admitted outside office hours. The median (interquartile range) emergency call to prehospital sample time was 33 minutes (25-41), and the median time from reported symptom onset or wake-up to prehospital sample was 53 minutes (38-85; n=394). Prehospital sampling was performed 31 minutes (25-42) earlier than admission blood sampling, and 37 minutes (30-47) earlier than admission neuroimaging. Quality control data from 25 participating EMS units indicated a 4-minute increase in median transport time (from arrival on-scene to hospital door) for study patients compared to patients of the preceding year. The hemolysis rate in serum and plasma samples was 6.5% and 9.3% for EMS samples, and 0.7% and 1.6% for admission samples collected with venipuncture. Conclusions: Prehospital biomarker sampling is feasible in standard EMS units and provides a median timesaving of over 30 minutes to obtain first blood samples. Large biobanks of prehospital blood samples will facilitate development of ultra-acute stroke biomarkers.


2021 ◽  
Vol 21 (8) ◽  
pp. 4400-4405
Author(s):  
Junyeop Lee ◽  
Nam Gon Do ◽  
Dong Hyuk Jeong ◽  
Sae-Wan Kim ◽  
Maeum Han ◽  
...  

Carbon monoxide (CO) is an odorless, colorless, tasteless, extremely flammable, and highly toxic gas. It is produced when there is insufficient oxygen supply during the combustion of carbon to produce carbon dioxide (CO2). CO is produced from operating engines, stoves, or furnaces. CO poisoning occurs when CO accumulates in the bloodstream and can result in severe tissue damage or even death. Many types of CO sensors have been reported, including electrochemical, semiconductor metal-oxide, catalytic combustion, thermal conductivity, and infrared absorption-type for the detection of CO. However, despite their excellent selectivity and sensitivity, issues such as complexity, power consumption, and calibration limit their applications. In this study, a fabricbased colorimetric CO sensor is proposed to address these issues. Potassium disulfitopalladate (II) (K2Pd(SO3)2) is dyed on a polyester fabric as a sensing material for selective CO detection. The sensing characteristics and performance are investigated using optical instruments such as RGB sensor and spectrometer. The sensor shows immediate color change when exposed to CO at a concentration that is even lower than 20 ppm before 2 min. The fast response time of the sensor is attributed to its high porosity to react with CO. This easy-to-fabricate and cost-effective sensor can detect and prevent the leakage of CO simultaneously with high sensitivity and selectivity toward CO.


2011 ◽  
pp. 1595-1604
Author(s):  
Scott P. Schaffer ◽  
Ian Douglas

Considerable effort has been devoted recently to development of systems or platforms that manage the learning, performance, or knowledge delivered to students and employees. These systems are generically labeled learning management systems (LMS), learning and content management systems (LCMS), performance support systems, and knowledge management systems (Rockley, 2002). Organizations increasingly use content management systems to deliver content objects to employees on a just-in-time basis to support knowledge and performance requirements (Rosenberg, 1999). While systems are developed that efficiently manage learning, knowledge, or performance, it seems desirable to consider how integration of each of these areas into a single system would benefit organizations. A major challenge to developing such systems has been the degree to which they are interoperable and the components within each are reusable. Reuse of data or information for learning or performance solution development is considered the primary driving force behind the movement toward object-based architectures for such systems (Douglas & Schaffer, 2002; Schaffer & Douglas, 2004). Ideas for integrating different sources of support for individuals and making its construction more cost effective have begun to take shape. Some efforts have focused on reusable and interchangeable (between different delivery systems) content objects, such as the U.S. Department of Defense Advanced Distributed Learning initiative (http://www.adlnet. org). A big challenge in development of support is the lack of a pedagogical model that takes advantage of object-based architectures while promoting collaboration and knowledge capture and sharing. A significant move in this direction has been outlined by Collis and Strjker (2003) who view the learner as a contributor of knowledge that may be captured and stored for reuse by future learners or course designers. An expansion of this idea, focused on in this article, is the reuse of the contributions of various members of a design and development team. This includes artifacts, decisions, and rationales related to activities such as the analysis of needs, identification of metrics, and identification of causes and possible solutions to workplace problems. This approach essentially attempts to link the analysis and design processes related to initial development of solutions with the ongoing adaptation and evaluation


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