Fabrication Process for On-Board Geometries Using a Polymer Composite-Based Selective Metallization for Next-Generation Electronics Packaging

Advancements in production techniques in PCB manufacturing industries are still required as compared to silicon-ICs fabrications. One of the concerned areas in PCBs fabrication is the use of conventional methodologies for metallization. Most of the manufacturers are still using the traditional Copper (Cu) laminates on the base substrate and patterning the structures using lithography processes. As a result, significant amounts of metallic parts are etched away during any mass production process, causing unnecessary disposables leading to pollution. In this work, a new approach for Cu metallization is demonstrated with considerable step-reducing pattern-transfer mechanism. In the fabrication steps, a seed layer of covalent bonded metallization (CBM) chemistry on top of a dielectric epoxy resin is polymerized using actinic radiation intensity of a 375 nm UV laser source. The proposed method is capable of patterning any desirable geometries using the above-mentioned surface modification followed by metallization. To metallize the patterns, a proprietary electroless bath has been used. The metallic layer grows only on the selective polymer-activated locations and thus is called selective metallization. The highlight of this production technique is its occurrence at a low temperature (20–45 °C). In this paper, FR-4 as a base substrate and polyurethane (PU) as epoxy resin were used to achieve various geometries, useful in electronics packaging. In addition, analysis of the process parameters and some challenges witnessed during the process development are also outlined. As a use case, a planar inductor is fabricated to demonstrate the application of the proposed technique.

A giant cutaneous horn of oral commissure: a case report

Cutaneous horn is a conical, circumscribed, dense hyperkeratotic protrusion from skin with epithelial cornification. It is also known by the Latin name ‘Cornu cutaneum’. This rare medical entity resembles animal horn but histological disparity is present between both. They are more commonly present in sun exposed sites or areas that are prone for actinic radiation, burns and hence frequently seen in forearm and upper part of face. Only few cases have been reported with cutaneous horns in unusual sites. Cutaneous horns occurring in oral cavity or perioral regions are extremely rare. The significance of knowing about this dead keratinous cutaneous horn is that it may occur as a part of or in association with a wide range of underlying pathologies, either malignant, premalignant or benign. Majority are due to benign pathologies. We report an unusual presentation of cutaneous horn in left oral commissure of a 45-year-old gentleman which is an extremely rare perioral location for such an ailment.

Evaluation of Radiative Transfer Model Calculations of Solar Actinic Flux Densities with HALO Aircraft Measurements

<p>Solar actinic radiation is driving atmospheric photochemistry. Consequently, chemistry-transport models rely on accurate model predictions of actinic flux densities to correctly reproduce the essential impact of photolysis processes. Cloud effects are most challenging in this context because of their potentially large influence and their variability. In this study, the effects of clouds, aerosols and ground albedos on solar actinic radiation are investigated using 1D satellite-aided radiative transfer calculations and in-situ aircraft measurements.</p><p>Spectral actinic flux densities in the range 280-650 nm are calculated with the latest version of the libRadtran model utilizing cloud products from geostationary satellites (NASA SatCORPS) as well as aerosol properties (MODIS, MOD08_D3), surface albedos (MODIS, MCD43A3) and total assimilated ozone columns (TEMIS, MSR-2) from polar orbiting satellites as key input parameters. The evaluation of the performance of the model output is made by comparison with data from several campaigns with the research aircraft HALO (High Altitude and Long Range Research Aircraft) where spectral actinic flux densities were measured during a total of around 90 research flights.</p><p>As a prerequisite to study cloud influence, clear-sky cases were investigated in detail to quantify the impact of the aerosol optical thickness and surface albedo on spectral actinic flux densities. Over land, radiative transfer calculations show good agreement with the measured data independent of wavelength and altitude within about 10% under clear sky conditions. Over the ocean the situation is complicated, because ocean surface albedos (OSA) are not available from satellite observations. Available OSA parametrizations, that depend on atmospheric conditions, tend to lead to a slight overestimation of upward-directed actinic flux densities in particular in the visible range, but the agreement for total actinic flux densities is still comparable with that over land. With sufficient agreement of modelled and observed actinic flux densities under clear sky conditions, flight paths with clouds will be included comprising above-cloud, in-cloud and below-cloud conditions. In the model, liquid cloud effects can be parametrized using Mie theory, but ice clouds pose a more complex problem, due to the wide range of possible structures of ice crystals. Finally, the intent of this study is to asses the quality of the radiative transfer modelled actinic flux densities based upon the satellite-derived cloud information.</p>

Key Role of Equilibrium HONO Concentration over the Soil

<p>Nitrous acid (HONO) is an important component of the nitrogen cycle. HONO can also be rapidly photolyzed by actinic radiation to form hydroxyl radicals (OH) and exerts a primary influence on the oxidative capacity of the atmosphere. The sources and sinks of HONO, however, are not fully understood. Soil nitrite, produced via nitrification or denitrification, is an important source for the atmospheric HONO production. [HONO]*, the equilibrium gas phase HONO concentration over the soil, has been suggested as key to understanding the environmental effects of soil fluxes of HONO (Su et al., 2011). But if and how [HONO]* may exist and vary remains an open question. In this project, a measurement method using a dynamic chamber has been developed to derive [HONO]* and the atmospheric soil fluxes of HONO can accordingly be quantified. We demonstrate the existence of [HONO]* and determine its variation in the course of soil drying processes. We show that when [HONO]* is higher than the atmospheric HONO concentration, HONO will be released from soil; otherwise, HONO will be deposited on soil. This work advances the understanding of soil HONO emissions, and the evaluation of its impact on the atmospheric oxidizing capacity and the nitrogen cycling.</p>

Acute Toxicity Ethanol Extract of Bidara Leaves (Ziziphus spina-christi L.) Against Liver and Kidney Function of White Rats

Bidara plants have the efficacy as antioxidants, anti-inflammatory,antimicrobial, anti-fungal and prevents tumours. Bidara is efficacious to protecthuman DNA cells caused by damage from actinic radiation. This study aims toexplore the acute toxicity test of the ethanol extract of Bidara leaves using whitemice as experimental animals. A total of 30 white rats (Rattus norvegicus) Wistarstrain obtained from the Eureka Research Laboratory (Palembang, Indonesia)weighing between 200 - 250 grams. After one week of adaptation, the mice wererandomly divided into the following six groups, each containing five animals:Normal control group and Bidara extract group (50mg/kg BW; 150 mg/kg BW;450 mg/kg BW; 1350 mg/kg BW; and 4050 mg/kg BW). This study shows thatthe extract of Bidara leaves has a relatively high toxic dose, namely at a dose of4050 mg/kg BW. Bidara leaf extract at doses below 1500 mg/kg BW, shows notoxic effect on the liver. In conclusion, bidara leaf extract has a toxic dose above4000 mg/kg BW in Wistar white rats.

Synthesis, structural features and gas-sensing properties of highly defective titanium dioxide

By the chemical reduction of sol-gel synthesized TiO2, nanoscale black titanium dioxide in anatase modification, characterized by the presence of large quantity of oxygen vacancies and pronounced extrinsic absorption, was obtained. Semiconducting chemical gas sensors on the basis of the obtained highly defective titanium dioxide demonstrate high output value towards ethanol vapor. The output value significantly increases additionally under actinic radiation conditions.

Influence of humidity and iron(iii) on photodegradation of atmospheric secondary organic aerosol particles

The absorption of solar actinic radiation by atmospheric secondary organic aerosol (SOA) particles drives condensed-phase photochemical processes, which lead to particle mass loss by the production of CO, CO2, hydrocarbons, and various oxygenated volatile organic compounds (OVOCs).

Oral Cancer and HPV Connection: A Review

HPV is the leading cause of oropharyngeal cancers and a few oral cavity cancers with increasing mortality across the globe. The risk factors for oral cancer are well known. Factors like tobacco chewing, smoking, alcohol consumption and actinic radiation have been extensively studied and clinically validated. However , Recently HPV has been shown to be a significant risk factor for oral and oropharyngeal cancers. The HPV family contains around 200 strains but it is important to note that only nine out of them are high risk and associated with cancers. Amongst them HPV16 is most strongly related with oral cancer. HPV associated cancers are different from cancers originating from other etiologies and thus , require a novel multidisciplinary treatment approach. The article is a review of Molecular Biology , Risk Factors ,Clinical aspects ,Diagnosis ,and Treatment of HPV associated Oral cancer .