ELISA Based Detection of Botulinum Neurotoxin Type F in Red Meat and Canned Fish

Botulinum neurotoxin (BoNT) is the most toxic protein molecule so far known to animals and humans, due to its extreme toxicity, CDC has been listed as category ‘A' Biological warfare agents. In India, there is no commercial detection system available for the detection of botulism. The present study was aimed to develop an ELISA based detection system for botulinum neurotoxin serotype F in red meat and canned fish. Polyclonal antibodies were generated against the recombinant BoNT/F LC protein and IgG was purified. Sandwich ELISA system was successfully optimized with LOD of ~ 7.8 ng/ml in PBS. Similarly, different concentrations of BoNT/F were spiked in red meat and canned fish and extracted the toxin and the detection LOD was achieved for red meat ~ 62 ng/ml and for canned fish ~ 31 ng/ml. The developed detection system is highly specific. The developed assay will be useful for the screening of botulinum toxins in a large number of food samples

Three-Dimensional Numerical Study of Conjugate Heat Transfer in Diverging Microchannel

Increase in applications of varying cross sectional area microchannels in microdevices has provided the need to understand fluid flow and heat transfer through such flow passages. This study focuses on conjugate heat transfer study through a diverging microchannel. Three-dimensional numerical simulations are performed using commercially available package. Diverging microchannels with different geometrical configurations (i.e. varying angle: 1-8°, depth: 86-200 μm, solid-to- fluid thickness ratio: 1.5-4) are employed for this purpose. Simulations are carried out for varying mass flow rate (3.3 x 10 –5 -8.3 x 10 –5 kg/s) and heat flux (2.4-9.6 W/cm 2 ) conditions. Heat distribution along the flow direction is studied to understand the effect of wall conduction. Wall conduction number ( M ) varies from 0.006 to 0.024 for the range of parameters selected in the study. Wall conduction is observed to be a direct function of depth and solid-to-fluid thickness ratio, and varies inversely with angle of diverging microchannel. It is observed that the area variation and wall conduction contribute separately towards redistribution of the supplied heat flux. This leads to reduced temperature gradients in diverging microchannel. The results presented in this work will be useful for designing future microdevices involving heating or coolin

Filamentous Soil Fungi from Ny-Ålesund, Spitsbergen, and Screening for Extracellular Enzymes

Soil filamentous fungi from Ny-Ålesund, Spitsbergen, were studied. A total of 30 fungal isolates were identified by morpho-taxonomy, and the identity of some morpho-taxonomically complex isolates was authenticated by ITS1-5.8S and ITS2 rDNA domain sequence similarity. The isolates belonged to 19 species under 14 genera (Acremonium, Arthrinium, Aspergillus, Cladosporium, Corynespora, Emericella, Geomyces, Mortierella, Mucor, Myrothecium, Penicillium, Phialophora, Preussia, Xylaria). To the best of our knowledge, Acremonium roseolum, Aspergillus aculeatus, Emericella nidulans, and Preussia sp. are the first northernmost records from Arctic soils. The viable fungal count in different soil samples varied from 0.5 • 104 to 2.0 • 105 g-1. Species richness in different soil samples was also calculated. Mortierella was one of the most dominant genera in Arctic soils. A temperature tolerance study was carried out for all the isolates, and representative species were screened for their extracellular enzyme activity (amylase, cellulase, phosphatase, and pectinase) at 4˚C and 20˚C. Among the 30 isolates, seven showed cellulolytic activity, two were phosphate solubilizers, three had amylolytic activity, and only one showed pectinolytic activity on solid media. CMCase (β1, 4-endoglucanase) activity was quantified in seven isolates that exhibited positive activity during preliminary screening. The records of enzyme activity for amylases, pectinases, and cellulases are the first from the fungi of Spitsbergen. The present study indicates the dominance in Ny-Ålesund of cellulolytic strains, which may serve as potent decomposers in Arctic tundra. These isolates may be used to facilitate the mineralization of cellulolytic wastes generated by human activities in colder hilly areas across the world, including the Himalayas in India.Nous avons étudié des champignons telluriques filamenteux de Ny-Ålesund, Spitzberg. Grâce à la morpho-taxonomie, nous avons identifié 30 isolats fongiques, et l’identité de certains complexes d’isolats morpho-taxonomiques a été authentifiée au moyen des similarités des séquences de domaines ITS1-5.8S et ITS2 DNAr. Les isolats relevaient de 19 espèces faisant partie de 14 genres (Acremonium, Arthrinium, Aspergillus, Cladosporium, Corynespora, Emericella, Geomyces, Mortierella, Mucor, Myrothecium, Penicillium, Phialophora, Preussia, Xylaria). Au meilleur de nos connais­sances, Acremonium roseolum, Aspergillus aculeatus, Emericella nidulans et Preussia sp. constituent les premiers enregis­trements aussi nordiques des sols arctiques. Le dénombrement viable de champignons dans différents échantillons de sol variait de 0,5 • 104 à 2,0 • 105 g-1. Nous avons également calculé la diversité des espèces prélevées dans différents échantillons de sol. Le genre Mortierella était l’un des plus dominants des sols arctiques. Nous avons étudié la tolérance à la température de tous les isolats, et des espèces représentatives ont été examinées du point de vue de l’activité enzymatique extracellulaire (amylase, cellulase, phosphatase et pectinase) à 4 ˚C et 20 ˚C. Parmi les 30 isolats, sept présentaient de l’activité cellulolytique, deux étaient des solubilisants du phosphate, trois présentaient de l’activité amylolytique et seulement un présentait de l’activité pectolytique dans le cas des solides. L’activité CMCase (β1, 4-endoglucanase) a été quantifiée dans sept isolats qui affichaient une activité positive au cours de l’examen préliminaire. Il s’agissait de la première fois que de l’activité enzymatique pour les amylases, pectinases et cellulases a été détectée dans les champignons de Spitzberg. Cette étude indique la dominance de souches cellulolytiques à Ny-Ålesund, souches qui peuvent servir de décomposeurs puissants dans la toundra arctique. Ces isolats peuvent servir à faciliter la minéralisation des déchets cellulolytiques émanant des activités humaines dans les régions montagneuses plus froides du monde entier, y compris l’Himalaya, en Inde

Stress analysis in 3D IC having Thermal Through Silicon Vias (TTSV)

TTSV is proposed for the removal of heat from between the IC layers as these TTSVs carries heat down to the sink. However, it may generate stress in Silicon. In the present paper, thermal-stress simulation of stack consists of three IC layers bonded face up is performed using finite element modeling tools. We also analyzed the stress generated in 3D IC containing TTSV. Further we proposed a method for lower stress around the TTSV. The method proposed decreases the Von Misses Stress by a value of 40Mpa on average considering all the IC layers. Thus by achieving this, functionality of the chip becomes more reliable

Allium stracheyi (Baker), the endangered and traditional medicinally important herb of Uttarakhand Himalaya, India: A Review

 Allium stracheyi (Alliaceae), is the high-altitude growing plant, commonly known as Jamboo, and Dhungar in Uttarakhand, India. It is a good source of income for the tribal communities and cultivars of Uttarakhand with medicinally and economically importance. A. stracheyi has higher amount of fibre and protein contents with lower fat and carbohydrates. It is used in various ailments. Considering phytoconstituents studies revealed different types of compounds like hydrocarbons, terpenes, terpenoids and sulfur-containing components as volatile constituents. The present study aimed to provide a general review of the available literature of A. stracheyi on phytochemistry, biological activities and pharmacological uses with special reference to traditional and economic importance

Targeted cooling with CVD diamond and micro-channel to meet 3-D IC heat dissipation challenge

Thermal simulation of a stack consists of three IC layers bonded “face up” is performed. It is shown that by inserting electrically isolated thermal through silicon via (TTSV) having Cu core and CVD diamond as a liner shell that extends across the layers to substrate, significant temperature reduction up to (103K) 62% can be achieved which also reflected through almost 60% reduction in thermal resistivity. Additionally simple microchannel integration with IC 3 layer and allowed fluid flow through the channel show transient temperature reduction. TTSV is also shown to be effective in mitigating severe heat dissipation issue facing 3-D IC bonded “face down” and logic layer stacked on memory substrate

Onset of Nucleate Boiling and Critical Heat Flux with Boiling Water in Microchannels

This paper focuses on experimental determination of onset of nucleate boiling (ONB) and critical heat flux (CHF) at the microscales, and comparison of these with available correlations. The working fluid is deionised water and microchannel of four different hydraulic diameters: 65, 70, 107 and 125 m, have been tested. Effect of hydraulic diameter (65-125 m), mass flux (60-1410 kg/m2s) and heat flux (0-910 kW/m2) on ONB and CHF has been studied in detail. The heat flux for onset of nucleate boiling increases with hydraulic diameter and mass flux. The critical heat flux tends to increase with a decrease in hydraulic diameter and with increasing mass flux. The effect of surface roughness on CHF has also been tested to a limited extent; no clear change in the CHF value was observed upon changing the surface roughness by an order of magnitude. The empirical correlations tested in this study predict the experimental data to varying extent. These results may help better determine the lower and upper limits of heat flux while designing heat sink for electronic cooling

Low temperature, low pressure CMOS compatible Cu -Cu thermo-compression bonding with Ti passivation for 3D IC integration

In this paper, we report the methodology of achieving low temperature, low pressure CMOS compatible Wafer-on-Wafer (WoW) Cu-Cu thermo-compression bonding using optimally chosen ultra-thin layer of Titanium (Ti) as a passivation layer. We systematically studied the effects of Ti thickness on bonding quality via its effects on surface roughness, oxidation prevention and inter diffusion of Cu. Through this study, we have found that a Ti thickness of 3 nm not only results in excellent bonding but also leads to a reduction in operating pressure to 2.5 bar and temperature to 175° C. The reduction in pressure is more than an order of magnitude lower relative to the current state-of-the-art. The lower operating pressure and temperature manifest themselves in a very good homogenous bond further highlighting the efficacy of our approach. Finally, our results have been corroborated by evidence from AFM study of the Cu/Ti surface prior to bonding. The bond strength of Cu-Cu as measured by Instron Microtester measurement system is found to be 190 MPa which compares very well with the reported literatures