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Science ◽  
2022 ◽  
Vol 375 (6577) ◽  
Author(s):  
Jeffrey S. Pigati ◽  
Kathleen B. Springer ◽  
Matthew R. Bennett ◽  
David Bustos ◽  
Thomas M. Urban ◽  
...  

Madsen et al . question the reliability of calibrated radiocarbon ages associated with human footprints discovered recently in White Sands National Park, New Mexico, USA. On the basis of the geologic, hydrologic, stratigraphic, and chronologic evidence, we maintain that the ages are robust and conclude that the footprints date to between ~23,000 and 21,000 years ago. Madsen et al . ( 1 ) question the veracity of calibrated radiocarbon ages used to constrain the antiquity of human trackways discovered recently at White Sands National Park (WHSA) Locality 2, New Mexico, USA ( 2 ). The ages were derived from seeds of the aquatic plant Ruppia cirrhosa , which they suggest may suffer from hard-water (or reservoir) effects, making them too old, potentially by thousands of years. We were well aware of this possibility, investigated it, and presented several lines of evidence that argued against such a problem. Here we respond to each of their four primary points.


Author(s):  
Neethu Mary George ◽  
Amruthavalli Potlapati

<p>Modern shampoos are much more than just cleansing agents. With rising demands for new milder and ‘greener’ products, the developments in the field of shampoo and conditioners are moving at a faster pace than ever before. Soaps were initially used to clean scalp but are not recommended for hair cleansing because they leave behind a soap scum when mixed with hard water that is difficult to rinse from the hair and scalp. There are different types of shampoos. Besides “normal” cleaning shampoo, there are “specific” shampoos that have additional ingredients targeting some hair problems. Dermatologists most frequently prescribe shampoos but little is taught in medical schools about the hair cosmetics. Most of the prescriptions are based only on the treatment of the scalp and usually disregards the hair fibre health. Hence it is imperative for dermatologists to known about the mechanism of shampoos, different surfactants and where to choose which shampoo.</p>


Author(s):  
Rusdianasari ◽  
Adi Syakdani ◽  
Muhammad Zaman ◽  
Febby Fitria Sari ◽  
Nabila Putri Nasyta ◽  
...  

Organic waste is waste that contains carbon compounds that come from living things, such as fruit and vegetable waste. However, the community is still not able to manage it optimally, even though organic and non-organic waste can still be processed into useful products. This effective way can be realized through the manufacture of eco-enzymes that can be applied at the household level. Eco-enzyme is a liquid extract produced from the fermentation of vegetable and fruit residues with brown sugar as a substrate. The eco-enzyme has a strong sweet and sour fermented aroma due to the peels of oranges, pineapples, and papayas. This environmentally friendly enzyme can be produced using fruit peel, brown sugar, and water. Eco-enzyme solution when mixed with water, will react and can be used as a liquid disinfectant. Disinfectants commonly used are generally derived from synthetic chemicals in the form of artificial chemicals. One of the natural ingredients that can be used as a disinfectant is eco-enzyme liquid. This study aims to make a disinfectant using an environmentally friendly enzyme liquid, namely eco-enzyme. The method used in this research is a mixed method of fermentation of orange peel waste, pineapple and papaya, brown sugar, and water with a ratio of 3:1:10. Analysis for eco-enzyme pH, and Phytochemicals, while for disinfectants include pH, total phenol content with UV-Vis Spectrophotometer, hard water emulsion stability, and antibacterial test. All samples of the disinfectant product met the requirements of SNI 06 – 1842 of 1995, besides that, the best disinfectant product was found in a ratio of 1:10 which could reduce bacterial growth.


2021 ◽  
Vol 3 ◽  
Author(s):  
Hilma Rantilla Amwele ◽  
Nnenesi Anna Kgabi ◽  
Liisa Indileni Kandjibi

The groundwater quality data from 1,137 boreholes in 10 regions of Namibia were assessed for sodium adsorption ratio (SAR), Kelly's ratio (KR), sodium percentage (Na%), magnesium adsorption ratio (MAR), total hardness (TH), soluble sodium percentage (SSP), potential salinity (PS), electrical conductivity (EC), and total dissolved solids (TDS) to determine the suitability for the irrigation. The groundwater was classified as follows: all the regions' groundwater shows the TH as very hard water of &gt;4.6 meq/l, PS as not suitable for irrigation (&gt;3 meq/l), and EC as very highly (0.75–2.25 dS/m). However, Na%: 10% of regions have doubtful water (&gt;80%), MAR: 30% of regions are not recommended for irrigation (&gt;50 meq/l), and TDS: 90% of the regions have slightly moderate (450–2,000 mg/l) and 10% have groundwater that is unsuitable for agricultural purposes (&gt;2,000 mg/l). The unsuitability of groundwater for irrigation could be due to higher concentrations of K+, Mg2+, Ca2+, and Cl− that has exceeded the FAO guideline for irrigation. Some groundwater qualities had inverse classification such as SAR all regions have excellent groundwater (&lt;10 meq/l), KR: 90% of regions have safe water (&lt;1 meq/l), Na%: 50% of regions have good groundwater (20–40%), 40% of the regions have permissible water (40–80%), and MAR: +70% of region's water is recommended for irrigation (&lt;50 meq/l).


2021 ◽  
pp. 831-836
Author(s):  
Yan Liang ◽  
Lu Ying Yang ◽  
Ai Di Huo ◽  
Wen Ke Guan

Chemical characteristics of surface water and phreatic water and their relationship with the growth of Populus euphratica Oliv. were explored. In the study area, hydrochemical types of the surface water were mainly SCaⅢ or ClNaⅢ (Based on the O. A. Arliekin's classification) and PH value of the surface water was below 8.0. The surface water from various sampling sites has a higher total hardness belonging to hard water and extremely hard water. The contents of sulfates and chlorides in the surface water in the protection zone ranged from 204.1 to 486.3 mg/l and from 70.9 to 239.9 mg/l, respectively. Phreatic water is mainly recharged by the surface water infiltration. In terms of water quality, TDS, total hardness and total alkalinity of phreatic water at W2 sampling point were 17.3, 9.3 and 4.7 times of surface water, respectively. Populus euphratica was able to grow normally in the environment of brackish water, where total hardness, total alkalinity, and TDS of overflowing river were in the range of 325.3~769.5, 142.6~290.3 and 782.2~1037.5 mg/l, respectively. The Populus euphratica in juvenile phase was a few, and its rejuvenation was confronted with difficulty. The present study can provide a reference for exploring the water quality characteristics of surface and phreatic water and their relationship with the growth of Populus euphratica. Bangladesh J. Bot. 50(3): 831-836, 2021 (September) Special


Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 6777
Author(s):  
Safaa El-Nahas ◽  
Abdulrahem S. Arafat ◽  
Hanan Salah El Din ◽  
Abdulrahman G. Alhamzani ◽  
Mortaga M. Abou-Krisha ◽  
...  

The strategic idea in this work was to increase pH values by employing natural alkali sources (i.e., HCO3− and CO32−) from four tested agro-ashes as an alternative to chemicals (i.e., lime or soda ash). The considerable proportion of carbonates and bicarbonates in the investigated ash products had remarkable features, making them viable resources. All ash materials showed a significant ability for Ca ion elimination at high initial Ca ion concentrations. A slight quantity of ash (10 g/L) was sufficient for usage on very hard water contents up to 3000 ppm. Finally, the tested agro-ash was free of cost. Furthermore, unlike other conventional precipitants, such as NaOH, Ca(OH)2, NaHCO3, Na2CO3, and CaO, they are cost effective and ecologically sustainable. There is no need to employ any additional chemicals or modify the agro-ash materials throughout the treatment process. The benefits of the manufactured ash were assessed using a SWOT analysis.


Author(s):  
RAGAA EL-SHEIKH ◽  
IBRAHIM HEGAZY ◽  
EHAB ZAGHLOOL ◽  
MOHAMED E. A. ALI ◽  
AYMAN A. GOUDA

Objective: The study presents simple tools for water resources quality classification based on its chemical compositions in Abu Zaabal area, eastern Nile Delta, Egypt and assess the water quality for different uses. Methods: 31 water samples were collected from different water resources in the study area and analyzed for physicochemical parameters. Hydrochemical relations, contour maps and statistical methods were used to estimate the contamination indices and evaluate the water resources for different purposes. Results: 83.3% of groundwater samples is fresh water and 16.7% are brackish water. 85.7% of surface water samples are fresh and 14.3% is saline. 92% of groundwater samples and 71.5% of surface water samples are very hard water. According to HPI values, 8% of the quaternary groundwater samples are good, 4% are poor, 4% are very poor and 84% of the samples are unsuitable. All groundwater samples and 71% of surface water samples are contaminated with respect to ammonia. Conclusion: Higher concentrations of TDS and heavy metal may be due to the clay nature of the soil, the marine sediments in the aquifer matrix together with the dissolution and leaching of minerals from agricultural, anthropogenic and industrial activities. The groundwater in the polluted zones is considered unsuitable for human drinking.


Diversity ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 549
Author(s):  
Marco Cantonati ◽  
Olena Bilous ◽  
Nicola Angeli ◽  
Liesbeth van Wensen ◽  
Horst Lange-Bertalot

Using light (LM, including plastid characterization on fresh material) and scanning electron microscopy (SEM), as well as a thorough morphological, physical, chemical, and biological characterization of the habitats, the present study aims at describing three species new to science. They belong to the genera Eunotia Ehrenb., Planothidium Round and L. Bukht., and Delicatophycus M.J. Wynne, and were found in two contrasting spring types in the northern Apennines. The three new species described differ morphologically from the most similar species by: less dense striae and areolae, and the absence of a ridge at the valve face-mantle transition (SEM feature) [Eunotia crassiminor Lange-Bert. et Cantonati sp. nov.; closest established species: Eunotia minor (Kütz.) Grunow]; narrower and shorter cells [Planothidium angustilanceolatum Lange-Bert. et Cantonati sp. nov.; most similar species: Planothidium lanceolatum (Bréb. ex Kütz.) Lange-Bert.]; barely-dorsiventral symmetry, set off ends, and lower density of the central dorsal striae [Delicatophycus crassiminutus Lange-Bert. et Cantonati sp. nov.; most similar species: Delicatophycus minutus M.J.Wynne]. Two of the three species we described are separated from the closest species by dimensions. Their description improved knowledge on two taxa (Eunotia minor s.l. and Planothidium lanceolatum s.l.) likely to be only partially resolved species complexes. We could also refine knowledge on the ecological profiles of the three newly-described species. Eunotia crassiminor sp. nov., as compared to Eunotia minor, appears to occur in colder inland waters with a circumneutral pH and a strict oligotrophy as well with respect to nitrogen. The typical habitat of Planothidium angustilanceolatum sp. nov. appears to be oligotrophic mountain flowing springs with low conductivity. Delicatophycus crassiminutus sp. nov. was observed only in limestone-precipitating springs, and is therefore likely to be restricted to hard water springs and comparable habitats where CO2 degassing leads to carbonate precipitation. Springs are a unique but severely threatened wetland type. Therefore, the in-depth knowledge of the taxonomy and ecology of characteristic diatom species is important, because diatoms are excellent indicators of the quality and integrity of these peculiar ecosystems in the face of direct and indirect human impacts.


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