Low Zinc Concentrations Research Articles

The prospective associations of fetal growth-related pregnancy complications with subsequent breastfeeding duration and markers of human milk production

BackgroundThe development of the breast for lactation occurs throughout pregnancy. It is unknown whether pregnancy complications resulting in poor fetal growth can affect breastfeeding (BF) success. ObjectivesWe examined whether fetal growth-related pregnancy complications were associated with earlier BF cessation and changes in the concentrations of human milk biomarkers of low milk production. MethodsWe used data from the Growing Up in Singapore Toward Healthy Outcomes study (n = 954). Human milk concentrations of protein, lactose, citrate, sodium, potassium, and zinc at 3 wk postpartum were available for 180 mother-infant dyads. We examined the associations of fetal growth measures, including term infants born small-for-gestational-age (SGA) (<10th percentile), pregnancies complicated by fetal growth deceleration (second to third trimester fetal growth dropped between major centiles), elevated umbilical artery resistance (>90th percentile) or hypertensive disorders of pregnancy (HDP) with 1) risk of ceasing BF (Cox regression) and 2) concentrations of human milk components (weighted linear regression). ResultsAdjusting for maternal education, smoking exposure, BF intentions, and prepregnancy BMI (in kg/m2), individuals who delivered SGA infants and those with HDP were more likely to breastfeed for a shorter duration when compared to those with uncomplicated pregnancies {adjusted hazard ratio [95% confidence interval (CI)]: 1.45 (1.11, 1.89) and 1.61 (1.14, 2.29), respectively}; associations were nonsignificant for fetal growth deceleration and umbilical artery resistance. SGA was not associated with concentrations of human milk biomarkers, but compared to participants with uncomplicated pregnancies, milk produced by those with HDP contained lower zinc concentrations [adjusted β coefficient (95% CI): –0.56 mg/L (–1.08, –0.04) mg/L]. ConclusionsIndividuals with HDP and those with SGA infants tend to breastfeed for a shorter duration; however, only HDP appear to be associated with biomarkers of compromised milk production. Further research and support are needed to help individuals with HDP and SGA achieve their BF goals.This trial was registered at clinicaltrials.gov as NCT01174875.

Rapid deterioration of steatotic liver disease due to portal vein stenosis after pancreaticoduodenectomy

Steatotic liver disease after pancreatoduodenectomy occurs due to various factors, such as exocrine pancreatic insufficiency, impaired intestinal absorption, and malnutrition. The mechanism of steatogenesis differs to that of conventional steatotic liver disease associated with obesity and insulin resistance. We experienced a rare case of rapidly progressive steatotic liver disease accompanied by portal vein stenosis in the early postoperative period after subtotal stomach-preserving pancreaticoduodenectomy for distal cholangiocarcinoma. Although there was a complication due to postoperative drain infection, the patient was discharged from hospital with no nutritional problems. Two months postoperatively, the patient presented to the emergency room with dyspnea. CT showed a markedly steatotic liver, ascites, and portal vein stenosis. A portal vein stent was inserted transhepatically and the steatotic liver disease gradually improved. During the postoperative course, there were no problems indicated by nutritional markers; although the patient had diarrhea associated with postoperative pancreatic exocrine insufficiency, the symptoms were mild and improved after administration of oral pancrelipase. Before the intervention, the patient had intestinal edema, exacerbation of diarrhea, and a low serum zinc concentration, suggesting that impaired absorption caused by intestinal blood stasis and gut barrier dysfunction contributed to the development of steatotic liver disease.

Effects and remediation of heavy metals contamination in soil and vegetables from different areas: A review

Heavy metals are non-biodegradable and thus persist in the environment, potentially infiltrating the food chain via crop plants and accumulating in the human body through biomagnification. Due to their toxic nature, heavy metal poisoning poses a severe threat to human health and the environment. Consuming vegetables contaminated with heavy metals can lead to increased accumulation of these metals in the human body. This review discusses the risks of heavy metal contamination in various areas, as reported in some research studies, and the implications for human health. Data obtained from several journals indicated that levels of lead (Pb) and cadmium (Cd) in vegetables were generally within permissible limits, though cadmium concentrations were found to be low in some studies. High concentrations of lead (Pb) can affect metabolic functions, growth, and photosynthetic activities. Cadmium (Cd) levels, which are lower than the permissible limit of 0.2 mg kg−1 set by WHO, can lead to chromosomal aberrations and sister chromatid exchanges in cells. Zinc (Zn) levels were within permissible limits except in lettuce and spinach in some findings. Low zinc content in vegetables impacts human health, plant health, and agricultural productivity. Addressing zinc deficiency requires integrated approaches such as soil management, crop biofortification, and dietary diversification. Ensuring adequate zinc levels is essential for improving public health and achieving sustainable agricultural practices. Addressing heavy metal contamination in vegetables requires a combination of remediation and preventive strategies. Implementing soil and water management practices can mitigate these risks and ensure the safe production of vegetables.

Agronomic biofortification of finger millet for zinc, and its influence on yield and partitioning of zinc, iron, and calcium in the plant

Zinc (Zn) deficiency in humans is the most common, and zinc requirement is catered mainly by cereal food grains which have lower zinc content. Finger millet is one of the staple food crops in Africa and India and has only 25 to 30 µg Zn g−1 of grain. Breeding efforts have improved the grain-Zn content to nearly 40 µg g−1 of grain, which is far below the recommended dietary allowance of 15 mg day−1 adult−1, and such varieties are not suited to all the finger millet cultivation regions. Therefore, the objective of the present studies is to enhance the grain-Zn content of locally adapted varieties through agronomic biofortification, which can be adapted for any variety and region. The easy, promising, and cost-effective approach is the soil or foliar application of zinc to increase the grain-Zn content. Present studies over four years revealed that the foliar application of 0.5% ZnSO4·7H2O solution at flowering and 20 days after flowering (DAF) is apt to increase the grain-Zn significantly to 40 µg g−1 of grain. Whereas the soil application of ZnSO4·7H2O at 12.5 kg ha−1 is appropriate to increase the grain yield to 504 g m−2 from 444 g m−2 in the control. The partitioning of zinc and calcium was higher toward the leaf sheath, leaf lamina, and husk than the other plant parts, whereas iron was toward the root. Therefore, the translocation of zinc from leaves to grain needs to be improved for further increase in grain-zinc of finger millet.

Zinc mediates control of nitrogen fixation via transcription factor filamentation

Plants adapt to fluctuating environmental conditions by adjusting their metabolism and gene expression to maintain fitness1. In legumes, nitrogen homeostasis is maintained by balancing nitrogen acquired from soil resources with nitrogen fixation by symbiotic bacteria in root nodules2–8. Here we show that zinc, an essential plant micronutrient, acts as an intracellular second messenger that connects environmental changes to transcription factor control of metabolic activity in root nodules. We identify a transcriptional regulator, FIXATION UNDER NITRATE (FUN), which acts as a sensor, with zinc controlling the transition between an inactive filamentous megastructure and an active transcriptional regulator. Lower zinc concentrations in the nodule, which we show occur in response to higher levels of soil nitrate, dissociates the filament and activates FUN. FUN then directly targets multiple pathways to initiate breakdown of the nodule. The zinc-dependent filamentation mechanism thus establishes a concentration readout to adapt nodule function to the environmental nitrogen conditions. In a wider perspective, these results have implications for understanding the roles of metal ions in integration of environmental signals with plant development and optimizing delivery of fixed nitrogen in legume crops.

Emerging Perspectives in Zinc Transporter Research in Prostate Cancer: An Updated Review.

Dysregulation of zinc and zinc transporters families has been associated with the genesis and progression of prostate cancer. The prostate epithelium utilizes two types of zinc transporters, the ZIP (Zrt-, Irt-related Protein) and the ZnTs (Zinc Transporter), to transport zinc from the blood plasma to the gland lumen. ZIP transporters uptake zinc from extracellular space and organelle lumen, while ZnT transporters release zinc outside the cells or to organelle lumen. In prostate cancer, a commonly observed low zinc concentration in prostate tissue has been correlated with downregulations of certain ZIPs (e.g., ZIP1, ZIP2, ZIP3, ZIP14) and upregulations of specific ZnTs (e.g., ZnT1, ZnT9, ZnT10). These alterations may enable cancer cells to adapt to toxic high zinc levels. While zinc supplementation has been suggested as a potential therapy for this type of cancer, studies have yielded inconsistent results because some trials have indicated that zinc supplementation could exacerbate cancer risk. The reason for this discrepancy remains unclear, but given the high molecular and genetic variability present in prostate tumors, it is plausible that some zinc transporters-comprising 14 ZIP and 10 ZnT members-could be dysregulated in others patterns that promote cancer. From this perspective, this review highlights novel dysregulation, such as ZIP-Up/ZnT-Down, observed in prostate cancer cell lines for ZIP4, ZIP8, ZnT2, ZnT4, ZnT5, etc. Additionally, an in silico analysis of an available microarray from mouse models of prostate cancer (Nkx3.1;Pten) predicts similar dysregulation pattern for ZIP4, ZIP8, and ZnT2, which appear in early stages of prostate cancer progression. Furthermore, similar dysregulation patterns are supported by an in silico analysis of RNA-seq data from human cancer tumors available in cBioPortal. We discuss how these dysregulations of zinc transporters could impact zinc supplementation trials, particularly focusing on how the ZIP-Up/ZnT-Down dysregulation through various mechanisms might promote prostate cancer progression.

Antibacterial property alterations induced by low zinc content in laser-structured brass

Brass, along with other copper-based alloys, exhibits advantageous antibacterial properties that can be further enhanced by altering the surface topography to increase bacterial adhesion. This enhancement is achievable through a higher contact area created by precise periodic structures, each approximately the size of a single bacterial cell. One method for generating these structures is ultrashort pulsed direct laser interference patterning (USP-DLIP). However, this process may induce chemical alterations in addition to topographical changes, depending on the substrate’s composition. To mitigate unfavorable chemical alterations, brass with a 15% zinc content was selected for this study. The antibacterial effectiveness of the modified surfaces was tested against Escherichia coli, providing initial insights into the interaction between bacteria and the substrate. The results indicate that modified brass with a 15% zinc content shows improved antibacterial activity. Overall, this research demonstrates that by modifying a surface with the appropriate chemical composition, effective bacterial elimination through contact can be achieved.

Fostering healthy aging through selective nutrition: A long-term comparison of two dietary patterns and their holistic impact on mineral status in middle-aged individuals—A randomized controlled intervention trial in Germany

Aging is associated with a decline in physiological functions and an increased risk of age-related diseases, emphasizing the importance of identifying dietary strategies for healthy aging. Minerals play a crucial role in maintaining optimal health during aging, making them relevant targets for investigation. Therefore, we aimed to analyze the effect of different dietary pattern on mineral status in the elderly. We included 502 individuals aged 50–80 years in a 36-month randomized controlled trial (RCT) (NutriAct study). This article focuses on the results within the two-year intervention period. NutriAct is not a mineral-modulating-targeted intervention study, rather examining nutrition in the context of healthy aging in general. However, mineral status might be affected in an incidental manner. Participants were assigned to either NutriAct dietary pattern (proportionate intake of total energy consumption (%E) of 35–45 %E carbohydrates, 35–40 %E fats, and 15–25 %E protein) or the German Nutrition Society (DGE) dietary pattern (proportionate intake of total energy consumption (%E) of 55 %E carbohydrates, 30 %E fats, and 15 %E protein), differing in the composition of macronutrients. Data from 368 participants regarding dietary intake (energy, calcium, magnesium, iron, and zinc) and serum mineral concentrations of calcium, magnesium, iron, copper, zinc, selenium, iodine, and manganese, free zinc, and selenoprotein P were analyzed at baseline, as well as after 12 and 24 months to gain comprehensive insight into the characteristics of the mineral status. Additionally, inflammatory status - sensitive to changes in mineral status - was assessed by measurement of C-reactive protein and interleukin-6. At baseline, inadequate dietary mineral intake and low serum concentrations of zinc and selenium were observed in both dietary patterns. Throughout two years, serum zinc concentrations decreased, while an increase of serum selenium, manganese and magnesium concentrations was observable, likely influenced by both dietary interventions. No significant changes were observed for serum calcium, iron, copper, or iodine concentrations. In conclusion, long-term dietary interventions can influence serum mineral concentrations in a middle-aged population. Our findings provide valuable insights into the associations between dietary habits, mineral status, and disease, contributing to dietary strategies for healthy aging.

Trace Elements in Alzheimer's Disease and Dementia: The Current State of Knowledge.

Changes in trace element concentrations are being wildly considered when it comes to neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease. This study aims to present the role that trace elements play in the central nervous system. Moreover, we reviewed the mechanisms involved in their neurotoxicity. Low zinc concentrations, as well as high levels of copper, manganese, and iron, activate the signalling pathways of the inflammatory, oxidative and nitrosative stress response. Neurodegeneration occurs due to the association between metals and proteins, which is then followed by aggregate formation, mitochondrial disorder, and, ultimately, cell death. In Alzheimer's disease, low Zn levels suppress the neurotoxicity induced by β-amyloid through the selective precipitation of aggregation intermediates. High concentrations of copper, iron and manganese cause the aggregation of intracellular α-synuclein, which results in synaptic dysfunction and axonal transport disruption. Parkinson's disease is caused by the accumulation of Fe in the midbrain dopaminergic nucleus, and the pathogenesis of multiple sclerosis derives from Zn deficiency, leading to an imbalance between T cell functions. Aluminium disturbs the homeostasis of other metals through a rise in the production of oxygen reactive forms, which then leads to cellular death. Selenium, in association with iron, plays a distinct role in the process of ferroptosis. Outlining the influence that metals have on oxidoreduction processes is crucial to recognising the pathophysiology of neurodegenerative diseases and may provide possible new methods for both their avoidance and therapy.

Impact of heavy metals (Cu, Fe, Pb, Zn) on carbon and nitrogen uptake of the diatom-bearing benthic foraminifera Heterosteginadepressa

Foraminifera are protists primarily living in benthic marine and estuarine environments. We studied uptake of inorganic carbon (C) and nitrogen (N) of the photosymbiont-bearing benthic coral reef foraminifera Heterostegina depressa in the presence of heavy metals.Incubation experiments were accomplished with artificial seawater enriched with copper, iron, lead and zinc at two different concentration levels (10 and 100 fold enriched in contrast to the usual culture medium). Additionally, isotopically labelled 13C-sodium bicarbonate and 15N-ammonium chloride were added to trace their assimilation over time (1 d, 3 d, 5 d, 7 d). Pulse-amplified modulated fluorescence measurements were performed to measure the potential impacts of heavy metals on chlorophyll fluorescence of the photosymbiont. Increased levels of copper (430.5 μg Cu/l) exhibited the greatest toxicity, while for low levels no effect on the overall metabolism of the foraminifera and the fluorescence activity of the photosymbiont could be detected. Iron (III) increased the symbiont activity, independent of concentration applied (44.5 and 513.3 μg Fe/l), which indicates Fe-limitation of the algal symbiont. Lead enrichment showed no detectable effect even at high concentration. Low concentrations of zinc (35.1 μg Zn/l) promoted the metabolism of the foraminifera, while high concentrations (598.4 μg Zn/l) were toxic. At low levels, two metals (Fe and Zn) promoted symbiont activity, at high levels, iron still boosted photosynthesis, but Zn and Cu had a negative impact on the obligatory photosynthetic symbionts.

Compositional Analysis of Complementary Foods Given by Mothers to Children Aged 6-23 Months in Giginyu Nassarawa Local Government Area, Kano State, Nigeria

Under nutrition among young children is high and poor complementary foods have been implicated. The objective of this study was to investigate compositional analysis of complementary foods given by mothers to children aged 6-23 months in Giginyu Nassarawa Local Government Area, Kano State, Nigeria using appropriate standard methods and compare with a commercial complementary food (control). Energy density was designated low if &lt; 0.8 kcal and contribution of meals to daily requirements (RDA) of protein, calcium and zinc for young children determined. The moisture, protein, ash, energy density, calcium, zinc, and phytate contents of the complementary meals (100g wet basis) ranged from 64.32-83.7%, 0.74-6.29%, 0.04-1.41%, 0.37-1.17 kcal/ml, 0.82-27.00 mg/100g, 0.022-0.277mg/100g and 0.05-1.68%, respectively. The soybean based meal, ‘SB’ was significantly higher (p&lt;0.01) than other meals including the control, in protein, ash, energy, calcium, zinc and phytate contents. All other meals met above 50% of the RDA for protein except CMS1 (33%), SMMG (42.1%), PS (19.7%) and MSMP (32.8%). Except SB and CMS2 that contributed above 20-37% of RDA for calcium and zinc, the rest of the complementary meals were very low in calcium and zinc content.The moisture contents of common complementary meals offered to older infants in Giginyu LGA, Kano State are quite high which affected the energy density of the meals. Except for pap/sugar and custard based meals, the meals had appreciable levels of protein contents. However, there was low calcium and zinc (micronutrients) contents of most of the meals with about 400 mls daily consumption.

Zinc-rich polyester powder coatings with iron phosphide: Lower zinc content and higher corrosion resistance

Zinc-rich polyester powder coatings with iron phosphide: Lower zinc content and higher corrosion resistance

Protecting the Achilles heel: three FolE_I-type GTP-cyclohydrolases needed for full growth of metal-resistant Cupriavidus metallidurans under a variety of conditions.

In Cupriavidus metallidurans and other bacteria, biosynthesis of the essential biochemical cofactor tetrahydrofolate (THF) initiates from guanosine triphosphate (GTP). This step is catalyzed by FolE_I-type GTP cyclohydrolases, which are either zinc-dependent FolE_IA-type or metal-promiscuous FolE_IB-type enzymes. As THF is also essential for GTP biosynthesis, GTP and THF synthesis form a cooperative cycle, which may be influenced by the cellular homeostasis of zinc and other metal cations. Metal-resistant C. metallidurans harbors one FolE_IA-type and two FolE_IB-type enzymes. All three proteins were produced in Escherichia coli. FolE_IA was indeed zinc dependent and the two FolE_IB enzymes metal-promiscuous GTP cyclohydrolases in vitro, the latter, for example, functioning with iron, manganese, or cobalt. Single and double mutants of C. metallidurans with deletions in the folE_I genes were constructed to analyze the contribution of the individual FolE_I-type enzymes under various conditions. FolE_IA was required in the presence of cadmium, hydrogen peroxide, metal chelators, and under general metal starvation conditions. FolE_IB1 was important when zinc uptake was impaired in cells without the zinc importer ZupT (ZIP family) and in the presence of trimethoprim, an inhibitor of THF biosynthesis. FolE_IB2 was needed under conditions of low zinc and cobalt but high magnesium availability. Together, these data demonstrate that C. metallidurans requires all three enzymes to allow efficient growth under a variety of conditions.IMPORTANCETetrahydrofolate (THF) is an important cofactor in microbial biochemistry. This "Achilles heel" of metabolism has been exploited by anti-metabolites and antibiotics such as sulfonamide and trimethoprim. Since THF is essential for the synthesis of guanosine triphosphate (GTP) and THF biosynthesis starts from GTP, synthesis of both compounds forms a cooperative cycle. The first step of THF synthesis by GTP cyclohydrolases (FolEs) is metal dependent and catalyzed by zinc- or metal-promiscuous enzymes, so that the cooperative THF and GTP synthesis cycle may be influenced by the homeostasis of several metal cations, especially that of zinc. The metal-resistant bacterium C. metallidurans needs three FolEs to grow in environments with both high and low zinc and cadmium content. Consequently, bacterial metal homeostasis is required to guarantee THF biosynthesis.

Effect of Graphene on Corrosion Resistance of Low Zinc Epoxy Coatings Applied to Low-Carbon Steel

To reduce the consumption of zinc resources, it is necessary to reduce the zinc powder content of epoxy zinc-rich coatings. However, the reduced zinc powder content tends to reduce the degree of connectivity in the layer, which leads to a reduction in the corrosion resistance of the coating. The effective zinc powder content was also reduced. Therefore, it is important to increase the connection capacity of the zinc powder in the coating while reducing the amount of zinc powder. In this paper, an epoxy coating with low zinc content is prepared by using flake zinc powder instead of spherical zinc powder. It also uses graphene to connect zinc powder in the coating to increase the electrical conductivity of the zinc powder in the coating. This results in an increase in the protection of the coating determined, although the cathodic protection of the coating was not prolonged by the results of open-circuit potential and electrochemical impedance spectroscopy. In addition, when the zinc powder in the coating is cleanly consumed, the complex nature of corrosion product formed with graphene can increase the barrier resistance of the coating thereby increasing the corrosion resistance.

Determination of the concentration of Aluminum and Zinc in adult teeth samples in Al-Najaf Governorate, Iraq

The primary objective of this study was to assess the potential effects of aluminium (Al) and zinc (Zn) on oral health by determining their concentrations in adult teeth samples. Teeth of materials, such as implants and restorative products, often contain small amounts of metallic elements that can interact with the oral environment and impact a patient's health. To quantitatively analyze the concentrations of Al and Zn in teeth samples collected from adults, atomic absorption spectroscopy was used. The results showed the concentration of two metals: Aluminium (Al) and Zinc (Zn) in the teeth of 30 samples from the sample. It is evident from the data that Al and Zn concentrations differ between individuals according to age groups. The highest concentration of Aluminium was found in a 19-year-old female with a concentration of 14.888 (ppm), while the highest concentration of zinc was found in a 54-year-old male with a concentration of 59.458 (ppm). The lowest concentration of Aluminium was found in a 32-year male with a concentration of 1.735 (ppm), while the lowest concentration of zinc was found in a 52-year female with a concentration of 1.867 (ppm). We conclude that the concentration of zinc in the dental samples was higher than that of Aluminium. This is because zinc plays an essential role in many body processes, including the formation of teeth and bones. It is a component of saliva that helps protect teeth from decay by reducing acids produced by bacteria in the mouth.

Zinc-rich polyester powder coatings with iron Phosphide: Lower zinc content and higher corrosion resistance

Many conductive fillers such as carbon black, carbon nanotube and graphene, have been developed to reduce zinc content for zinc-rich coatings, but very few of them could reduce zinc content by 10 % while maintaining the original corrosion protection ability. The carbon-based conductive additives have the issue of corrosion promotion after cathodic protection. In this study, low-cost iron based conductive additive, iron phosphide was used to reduce zinc content in environmentally friendly zinc-rich polyester powder coatings. We investigated the anti-corrosive performance of the prepared coatings by open circuit potential, electrochemical impedance spectroscopy measurements and neutral salt spray tests. The corrosion products were analyzed with Raman spectroscopy, X-ray diffraction and scanning electron microscopy equipped with energy dispersive X-ray spectroscopy. It was found that iron phosphide, due to its conductive nature, inert chemistry, activation function and barrier effect of the lamellar shape, can establish cathodic protection at a low zinc content of 45 wt% with an active protection period of 20 days. It can replace 10 wt% of zinc in 75 wt% zinc-rich polyester powder coatings while maintaining the original cathodic protection ability, as long as 86 days for a 40 μm film. In addition, iron phosphide can significantly inhibit localized corrosion and decrease corrosion creepage by about 20 % during 2500 h salt spray tests. Moreover, a possible corrosion protection mechanism for iron phosphide in zinc-rich polyester coatings was proposed.

Zinc – a scoping review for Nordic Nutrition Recommendations 2023

Zinc is essential for several biological processes including those critical for the immune system, DNA synthesis, cell division, and growth. Zinc is involved in the pathophysiology of chronic diseases and protects proteins and lipids from oxidative damage. Inadequate zinc intake and low plasma zinc concentration are associated to an increased risk of chronic diseases such as cardiovascular diseases and type 2 diabetes; however, the evidence is limited. Zinc deficiency increases the risk of infections and poor growth and may contribute to the high burden of infectious diseases and stunting in children living in low- and middle-income countries. The risk of zinc deficiency in the populations of the Nordic and Baltic countries is low.

Змочування ZnO-кераміки сплавами системи срібло—мідь у вакуумі

Zinc oxide is a wide-gap semiconductor with unique properties, used for the manufacture of catalysts, electrodes, transistors, etc. In these applications, there is a need for metallization and joining of ZnO-based materials, using of molten metal filler is an effective method. Contact of zinc oxide and liquid metals is almost not studied in comparison to other oxide materials. In this work the wetting of zinc oxide based ceramic with metal melts of the silver-copper system in high vacuum was studied. Alloys with concentration of copper (% (at.)) 0 (pure silver), 5, 10, 20, 30, 39, 100 (pure copper) were used. Increasing the concentration of copper in the silver-copper melts significantly improves the wetting of ZnO-ceramic with these liquids, the contact angles decrease from 137° for the pure silver to 28° for the pure copper. Investigations of the microstructure show presence of relatively thin transition layers on the interfaces for silver-copper alloys, for the pure copper case the interface has complex “island-like” microstructure. Also a ruination of ZnO-ceramic substrates due to an interaction with metal melt was noted, the higher copper concentration, the more intensive ruination. Also some signs of the presence of zinc in the metal drops solidified on the zinc oxide surface were revealed, such as, intensive oxidation of the drops in air at room temperature. The oxidation shows complex multiphase microstructure of the solidified drops. After wetting of the zinc oxide with pure copper the solidified metal has microstructure of brass (Cu—Zn alloy) with low zinc concentration. The effects observed can be explained by sublimation of the zinc oxide under experimental conditions (high temperatures, vacuum) with formation of gaseous products (oxygen and vapor of zinc), which subsequently dissolve in silver-copper liquid drops. In particular, the dissolution of oxygen in the Ag—Cu melt improves its wetting of surfaces of solid oxides and presence of zinc in solidified drops provides its oxidization in air. Keywords: zinc oxide, wetting with metals, contact interaction, microstructure, transition layer.

Petrographical and Geochemical Features of Sulfide Mineralization in the Walash Group, Gallala Area, Kurdistan Region of Iraq

In this article, a Fe-rich sulfide mineralization hosted within the Walash Group in the Gallala area, on the northwestern side of the Zagros Orogen is investigated for the first time. The mineralization occurs as massive sulfide veins and veinlets, as well as disseminated within volcanic lithologies. The objective of the study is to characterize the sulfide-rich mineralization using petrographical and geochemical methods, applied in both the ores and the corresponding host formations, including the characterization of volcanic rock alteration. Petrographic data indicates the presence of Fe-rich sulfide mineralization in altered basaltic andesite to andesite rocks, which are affected by hydrothermal alteration such as actinolization, chloritization, sericitization, and epidotization. The geochemical analysis of the fresh rock samples reveals enrichment of iron in the suture zones, but low copper and zinc concentrations. The mineralogical and textural signatures of sulfide minerals lead to inferring that the ore mineralization origin is volcanogenic to the hydrothermal type of deposits.

THE INFLUENCE OF INDUSTRIAL EFFLUENT ON CHALLAWA RIVER WATER QUALITY

Water from River Challawa was assessed to test the influence of industrial effluent on the quality of water from the river. Sample collection was done in the month of June, 2023 at the end of dry season. At each sampling three (3) samples were collected to ensure accuracy by replication. A total of twenty-seven samples (27) were collected. Descriptive statistics was carried out on the data. The results obtained were compared with FEPA and WHO standards. A paired sample t-test was also carried out to test for any significant difference in the mean value of parameters upstream and downstream of points of discharge of effluents. Based on the findings of the research, it was concluded that, BOD, TDS and EC at the effluent point before and after have no any significant effect on the quality water from Challawa River. The findings of the study also revealed absence of lead and low concentration of zinc in the water. It was recommended that, the water from River Challawa can be used for irrigation with good management practices.