A PROENVIRONMENTAL VALUE CONSTRUCT TO DEAL WITH PLASTIC POLLUTION

2022 ◽  
Vol 13 (1) ◽  
pp. 0-0
Keyword(s):  
Food Chains ◽  
Controlled Environment ◽  
Plastic Pollution ◽  
Average Life ◽  
Human Wellbeing ◽  
Industrial Sectors ◽  
Synthetic Materials ◽  
Product Lifetime ◽  
The Mean ◽  
Source Use

Plastics are man-made synthetic materials. They are made mostly from crude oil even though natural gas and coal could also be used for manufacturing plastics. The multiplicity of its uses together with its versatile properties has made it indispensable to modern living. The average life of plastics differs in various industrial sectors. The generation of waste depends on the mean-product lifetime of the product into which plastics have been integrated. And when this waste is not handled properly (recycled or incinerated under controlled environment), the problem of pollution emerges. Plastics in the form of microplastics have been found in food chains as well, threatening human wellbeing. A model to better understand the source - use and afteruse of plastics is the central focus of this article. It looks at the need for building a sustainable model to deal with plastic pollution.

scholarly journals Conduction velocity of the rabbit facial nerve: a noninvasive functional evaluation

2003 ◽  
Vol 17 (2) ◽  
pp. 126-131 ◽  
Author(s):  
Belmiro Cavalcanti do Egito Vasconcelos ◽  
Cosme Gay Escoda ◽  
Ricardo José de Holanda Vasconcellos ◽  
Riedel Frota Sá Nogueira Neves
Keyword(s):  
Facial Nerve ◽  
Conduction Velocity ◽  
Nerve Conduction ◽  
Action Potentials ◽  
Functional Evaluation ◽  
Surface Electrodes ◽  
Nerve Grafts ◽  
Synthetic Materials ◽  
Facial Nerves ◽  
The Mean

The aim of this study was to evaluate standardized conduction velocity data for uninjured facial nerve and facial nerve repaired with autologous graft nerves and synthetic materials. An evaluation was made measuring the preoperative differences in the facial nerve conduction velocities on either side, and ascertaining the existence of a positive correlation between facial nerve conduction velocity and the number of axons regenerated postoperatively. In 17 rabbits, bilateral facial nerve motor action potentials were recorded pre- and postoperatively. The stimulation surface electrodes were placed on the auricular pavilion (facial nerve trunk) and the recording surface electrodes were placed on the quadratus labii inferior muscle. The facial nerves were isolated, transected and separated 10 mm apart. The gap between the two nerve ends was repaired with autologous nerve grafts and PTFE-e (polytetrafluoroethylene) or collagen tubes. The mean of maximal conduction velocity of the facial nerve was 41.10 m/s. After 15 days no nerve conduction was evoked in the evaluated group. For the period of 2 and 4 months the mean conduction velocity was approximately 50% of the normal value in the subgroups assessed. A significant correlation was observed between the conduction velocity and the number of regenerated axons. Noninvasive functional evaluation with surface electrodes can be useful for stimulating and recording muscle action potentials and for assessing the functional state of the facial nerve.

Presence and Quantification of Microplastic in Urban Tap-Water

2020 ◽  
Author(s):  
Claudia B. Pratesi ◽  
Maria Aparecida A.L. Santos Almeida ◽  
Geysa S. Cutrim Paz ◽  
Marcelo H. Ramos Teotonio ◽  
Felipe Mendes dos Santos Cardia ◽  
...  
Keyword(s):  
Tap Water ◽  
The South ◽  
Plastic Pollution ◽  
Wing Area ◽  
Health Crisis ◽  
Toxicological Effect ◽  
The North ◽  
Study Results ◽  
The Mean ◽  
Number Of Particles

Abstract Background: Plastic pollution is a rapidly growing environmental and human health crisis, with no sign of improvement. Since 2012 the number of studies on plastic pollution has quadrupled, and macro to nano-size plastics have been documented even in the planet's remote biomes. Studies have shown contamination by microplastics (MPs) in various types of food consumed by humans, including seafood, honey, sugar, salt, tap-water and bottled water and beer. The study's objective was to detect the possible contamination by MPs in drinking water samples collected from the two main residential and commercial areas of Brasília.Methods: A total of 32 samples of tap water were collected, 16 samples in the south zone, and 16 samples in the north zone of the city (respectively, South Wing and North Wing). Samples were processed and transferred to the Sedgewick-Rafter counting cell chamber. The presence of MPs particles was analyzed using a Nikon Eclipse fluorescence microscope.Results: MPs were found in 100% of the samples. The mean MPs per 500 ml found in the South Wing area was 97, while the mean number of particles in the North Wing area was 219.Conclusion: The study results reveal a disturbing amount of MP particles in Brasilia's tap-water. This surprising number of particles in tap-water is especially concerning considering that tap-water is not the only source of MPs to which people are exposed. The cumulative and toxicological effect of this chronic exposure is alarming.

Effect of Temperature on the Synthesis of Jojoba Wax

1985 ◽  
Vol 12 (4) ◽  
pp. 355 ◽  
Author(s):  
RL Dunstone ◽  
A Benzioni ◽  
ML Tonnet ◽  
P Milthorpe ◽  
A Shani
Keyword(s):  
Field Studies ◽  
Effect Of Temperature ◽  
Maximum Temperature ◽  
Wax Ester ◽  
Controlled Environment ◽  
Percentage Elongation ◽  
Jojoba Wax ◽  
Seed Growth ◽  
The Mean ◽  
Long Chain

Seed was collected from jojoba [Simmondsia chinensis (Link) Schneider] plants growing at three field sites in two years. The wax percentage was determined by nuclear magnetic resonance and the compositions of the wax and the ethanolysis products (one site only) were determined by gas chromatography. The mean wax concentration varied from 49.2 to 55.1% over all sites and years. The percentage of long-chain wax esters (>C40) decreased linearly with increase in mean maximum temperature during the period of linear seed growth (r� = 0.93). The decrease in long-chain esters was associated with a decrease in the C22 and C24 fatty acids and alcohols. Data from controlled environment studies and from field studies were used to assess the effect of temperature on the percentage elongation, reduction and esterification of acyl-CoAs of carbon lengths 18-22. High temperature lowered the specificity for elongation of C20-C22 and of C22-C,24 and increased the specificity for reduction of the C20 acid to its corresponding alcohol. The amount of C42 wax ester was greater than would be expected by random association of the alkoxy-acyl groups but this preference was not as great at high temperatures.

Effects of sow, udder section and time on colostrum immunoglobulin G (IgG) concentrations and piglet colostrum intake

1998 ◽  
Vol 1998 ◽  
pp. 159-159
Author(s):  
G. Jones ◽  
S.A. Edwards ◽  
S. Jagger ◽  
S. Hoste
Keyword(s):  
Milk Composition ◽  
Milk Intake ◽  
Individual Growth ◽  
Controlled Environment ◽  
Lactation Period ◽  
Weekly Basis ◽  
Daily Group ◽  
The Mean ◽  
Sow Nutrition ◽  
Better Than

Relationships between sow nutrition, milk yield, milk composition and piglet performance during lactation have been studied in numerous experiments. However, the subsequent effects of these pre-weaning factors on post-weaning piglet performance are less well studied. Commonly a growth check in piglets in response to weaning is noted, but to date it is unknown why some piglets do better than others in this period. The present experiment explored some of the pre-weaning factors that could explain the variability in piglet post-weaning growth.The performance of piglets from 41 litters was monitored during a lactation period of 26 days. Litter size was standardised to 10 piglets, which were not offered creep food. Piglets were weighed individually on a weekly basis from farrowing to weaning at 26 days. Daily litter milk intake was estimated by a weigh-suckle-weigh technique in 24 litters on 4 occasions at 5 day intervals across lactation. On the day after each of these days, the composition of milk was determined from milk samples obtained by hand milking following oxytocin injection. Litter milk intake and composition of milk were used to calculate the mean daily piglet nutrient intakes during lactation. After weaning some piglets were sacrificed for the analysis of body composition and 310 piglets out of the 41 litters were penned in litter groups in controlled environment flat decks for two weeks to monitor daily group feed intakes and weekly individual growth rates.

Are Mexican Net Discount Rates Stationary? An Application for Lost Earnings Damages Involving Undocumented Workers

2014 ◽  
Vol 25 (2) ◽  
pp. 128-152 ◽  
Author(s):  
Antonio Avalos ◽  
R. Sean Alley
Keyword(s):  
Time Series ◽  
Empirical Evidence ◽  
Case Law ◽  
Discount Rates ◽  
Undocumented Workers ◽  
Industrial Sectors ◽  
Relevant Case ◽  
Mexican Government ◽  
The Mean

AbstractThis paper provides empirical evidence on the behavior of various Mexican Net Discount Rates (NDRs) by examining the time series properties of several yields on Mexican government securities and annual wages for nine industrial sectors. Results indicate that NDRs are characterized as a stationary series around a shift in its mean. The forecast for the mean of the NDRs should be based on the period after the time of the shift, which took place in 1994. The discussion addresses relevant case law and the application of the NDR approach to the calculation of damages for Mexican undocumented workers as an effort to equip forensic economists with the tools to conduct such estimates.

Tree lines

1989 ◽  
Vol 324 (1223) ◽  
pp. 233-245 ◽  
Keyword(s):  
Growing Season ◽  
Early Spring ◽  
Summer Temperature ◽  
Northern Europe ◽  
Late Winter ◽  
Controlled Environment ◽  
Cold Climates ◽  
Tree Line ◽  
The Mean ◽  
Boreal Period

Trees do not generally grow in places where the mean temperature of the warmest month is less than about 10 °C. At their limit, trees are often short and crooked, the condition known as krummholz ; and the transition from tall forest to dwarf shrubby vegetation is often abrupt, forming a distinct tree line. Tree lines fluctuate with climatic change. There is compelling evidence to suggest that they shift to higher elevations and higher latitudes in warmer periods. In northern Europe, they were about 200 m higher in the Boreal period when the temperature is believed to have been 2 °C warmer than now. Controlled-environment studies and tree-ring evidence also point to considerable sensitivity of growth at the tree line to fluctuations in the summer temperature. Forest vegetation differs aerodynamically from dwarf vegetation in being aerodynamically rough. Consequently, the temperatures of above-ground tissues are closely coupled to temperatures of the air. In contrast, shorter vegetation experiences tissue temperatures and microclimates that depend substantially on other climatological variables, notably radiation and wind speed. Short vegetation is, on average, warmer than the air; this is the main reason why dwarf shrubs can succeed in cold climates where trees fail to grow and reproduce. Water stress commonly occurs in late winter and early spring when soil water is frozen. The foliage of trees at the tree line displays an inability to restrict water loss, either because the epidermis is damaged by abrasion or because the cuticle does not properly develop in the reduced growing season. Consequently, the longevity of leaves is reduced. Winter damage to trees is also likely as a result of gales and the deposition of ice in the canopy, both of which break branches and may contribute to the generally misshapen form of the crown.

A note on the effect of temperature on the performance of early-weaned pigs

1979 ◽  
Vol 29 (3) ◽  
pp. 423-426 ◽  
Author(s):  
K. J. McCracken ◽  
B. J. Caldwell ◽  
N. Walker
Keyword(s):  
Conversion Ratio ◽  
Feed Conversion Ratio ◽  
Effect Of Temperature ◽  
Controlled Environment ◽  
Feed Conversion ◽  
Winter Conditions ◽  
Satisfactory Performance ◽  
Temperature Regimes ◽  
The Mean ◽  
Two Temperature

ABSTRACTTwo temperature regimes were compared in relation to the growth and feed conversion ratio of groups of cage-reared pigs between 10 and 38 days of age. The treatments were: 27°C at 10 days reducing by 1°C every 4 days to 20°C at 38 days; and 27°C at 10 days reducing by 1°C daily to 20°C at 17 days and then remaining constant. Twelve replicates using 244 pigs were completed, the group size varying between 9 and 12 pigs. The mean growth rates on the two temperature regimes were respectively 234 and 243 g/day, and in both cases feed conversion ratio (kg DM/kg gain) averaged 1·03. It is concluded that temperatures lower than those currently recommended for pigs weaned at 14 to 16 days into controlled-environment houses would support satisfactory performance with direct savings in heating costs under winter conditions.

scholarly journals ESTIMATIONS OF CARBON FOOTPRINT FROM ELECTRICITY CONSUMPTION DURING COVID-19 LOCKDOWN AND PRE-LOCKDOWN IN BUTUAN CITY

2021 ◽  
Vol XLVI-4/W6-2021 ◽  
pp. 49-56
Author(s):  
L. C. S. Asube ◽  
R. L. Sinadjan
Keyword(s):  
Carbon Dioxide ◽  
Spatial Distribution ◽  
Greenhouse Gas ◽  
Carbon Footprint ◽  
Carbon Dioxide Emissions ◽  
Electricity Consumption ◽  
Public Buildings ◽  
Industrial Sectors ◽  
Northern Areas ◽  
The Mean

Abstract. The electricity consumption for commercial, residential, and industrial sectors is considered the primary cause of increasing carbon dioxide emissions. To calculate the carbon footprint, the researcher used Carbon Footprint Ltd. This study aims to quantify the carbon footprint associated with the consumption of electricity by sectors (residential, commercial, industrial, public buildings, and streetlights) in Butuan City during the pre-lockdown period (January and February), and then compare these with the carbon footprint calculated during the lockdown period (March and April 2020). A GIS-based approach was applied to generate the spatial distribution across the 86 barangays of Butuan City. The study findings that the carbon footprint in the lockdown period is ∼ −17% lower than the mean carbon footprint calculated for the pre-lockdown period. In absolute values, the total estimated carbon footprint during the pre-lockdown and lockdown period was ∼ 10,947 mtCo2e and ∼ 9,138 mtCo2e, respectively. Furthermore, the findings imply that the central and northern areas have the highest impact of savings on average ∼ 130 mtCo2e of greenhouse gas avoided by barangays. This research provides quantitative insight to understand the measured generated in lockdown and pre-lockdown periods.

scholarly journals The mean lives of excited neon atoms

1934 ◽  
Vol 143 (850) ◽  
pp. 588-604 ◽  
Keyword(s):  
Excited States ◽  
High Frequency ◽  
The State ◽  
Reliable Information ◽  
Neon Atom ◽  
Average Life ◽  
High Frequency Discharge ◽  
First Approximation ◽  
The Mean ◽  
Upper Level

Since the first experiments by Wien many methods have been used to find the average lives of the excited states of different atoms. Most of these methods are applicable to particular atoms only, and the amount of reliable information in this field is still surprisingly meagre. The method described here depends in effect on the measurement of the lag which exists between the excitation and emission of light from atoms in a high-frequency discharge. This lag, or rather quantity actually measured, is itself a first approximation to the average life τ of the state concerned, and it is shown later how a more accurate value of τ may be deduced from it. Results are given for six excited states of the neon atom, but the method may be used for any substance whose spectrum can be obtained from a high-frequency discharge. The values of τ for neon range from 3·9 to 20·10 -8 seconds, and it is shown that lines originating from the same upper level lead to the same value of τ for that level.

Marine and continental food webs: three paradoxes?

1994 ◽  
Vol 343 (1303) ◽  
pp. 57-69 ◽  
Keyword(s):  
Food Webs ◽  
Surface Area ◽  
Net Primary Productivity ◽  
Food Chains ◽  
Marine Animal ◽  
Stocks And Flows ◽  
Oceanic Species ◽  
The Mean ◽  
The Many ◽  
Chain Lengths

Carbon stocks and flows give a picture of marine and continental biotas different from that based on food webs. Measured per unit of volume or per unit of surface area, biomass is thousands to hundreds of thousands of times more dilute in the oceans than on the continents. The number of described species is lower for the oceans than for the continents. One might expect that each species of organism would therefore feed on or be consumed by fewer other species in the oceans than on the continents. Yet in reported food webs, the average oceanic species interacts trophically with more other species than the average terrestrial or aquatic species. Carbon turnover times imply that the mean adult body length of oceanic organisms is 240 to 730 times shorter than that of continental organisms. By contrast, in reported food webs, marine animal predators are larger than continental animal predators, and marine animal prey are larger than continental animal prey, by as much as one to two orders of magnitude. Estimates of net primary productivity (NPP) per unit of surface area or per unit of occupied volume indicate that the oceans are several to hundreds of times less productive than the continents, on average. If NPP limited mean chain length in food webs, oceanic food chains should be shorter than continental chains. Yet average chain lengths reported in published food webs are longer in oceans than on land or in fresh water. In reconciling these unexpected contrasts, the challenge is to determine which (if any) of the many plausible explanations is or are correct.

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