Changes In Concentration Research Articles

Carbon nanostructures in polyvinyl alcohol-based silver nanocomposites for serum albumin concentration sensing

Introducing carbon nanostructures in polyvinyl alcohol (PVA) matrix as strengthening elements by solution dispersion method is already known. Here, the plasmonic sensor surfaces interspersed with carbon nanomaterials are studied for their durable and better sensing capabilities. Carbon quantum dots (CQD) and Multiwall carbon nanotubes (MWCNT) are the carbon nanostructures used in the polyvinyl alcohol-silver nanocomposite to develop plasmonic sensing surfaces. Fiber optic unclad U-bent surfaces are encapsulated in the carbon nanostructure dispersed PVA-silver nanocomposite. The surface is further functionalized with the polyelectrolyte poly(allylamine) hydrochloride (PAH) for better bioconjugation. In the available sensor literature, the evaluation of the sensing layer stability after multiple sensing trials is almost nil. In this work, the sensor surface plasmonic performance after multiple sensing trials is evaluated. The results show that plasmonic biosensors with improved sensing performances can be developed by introducing carbon nanomaterials in PVA-silver nanocomposites. The developed sensor heads are used to sense Bovine Serum Albumin (BSA) concentration changes.

Understanding precipitation concentration changes, driving factors, and responses to global warming across mainland China

Global warming has increased the frequency and intensity of extreme precipitation events, leading to significant changes in temporal precipitation patterns. These temporal irregularities have exacerbated the occurrence of disasters such as droughts, floods, landslides, and mudslides. Despite this, comprehensive insights into precipitation concentration variations, their driving factors, and their relationship with global warming across nine river basins in mainland China remain insufficient. In this study, the CN05.1 gridded daily precipitation dataset from 1961 to 2020 is utilized to calculate the precipitation concentration index (PCI), precipitation concentration degree (PCD), and precipitation concentration period (PCP). Employing Random Forest and correlation analysis, the study address these gaps. The results indicate that: (1) Northern river basins exhibit significant temporal irregularities in precipitation patterns, whereas southern basins show more uniform temporal distributions in mainland China from 1961 to 2020. The decrease in the proportion of summer precipitation and the increase in spring and winter proportions have led to the decline in PCI across mainland China over the past sixty years. Additionally, the increase in moderately heavy and heavy rainfall events has caused more dispersed daily precipitation, decreasing PCD. (2) The primary factors influencing PCI and PCD are El Niño-Southern Oscillation (ENSO), South mainland China Sea Summer Monsoon Index (SCSSMI), and Arctic Oscillation (AO). PCI, PCD, and PCP are positively correlated with latitude and altitude in mainland China, while coastal basins show a significant negative correlation with longitude. (3) PCI, PCD, and PCP exhibit negative responses to global warming, with some basins experiencing a reduction in precipitation concentration of over 10 % per 1 K temperature rise from 1961 to 2020. Light precipitation frequency shows a negative response, whereas intense precipitation frequency displays a positive response. For precipitation exceeding the 99th percentile, some basins demonstrate response rates exceeding 20 %/K. These findings contribute to a deeper understanding of precipitation concentration dynamics in mainland China and offer scientific basis for mitigating droughts, floods, and managing water resources.

Passive RFID integrated sensors based on ZnO/CuO/RGO and SnO2/CuS/RGO nanomaterials are used for CO2 and ethanol detection in fruit and vegetable storage and transportation

This article proposes and designs a passive RFID integrated dual parameter gas sensor that can respond to ethanol and carbon dioxide gases at room temperature. Firstly, nanocomposite sensitive materials were prepared by hydrothermal method, and their microstructure and elemental composition were analyzed through TEM, SEM, XRD, XPS and UPS characterization tests. The dual frequency gas sensing antenna was designed and optimized using HFSS software, and a high-precision engraving mechanism was used to prepare the sensor model. Finally, two different gas sensitive materials were deposited on the corresponding positions of the symmetric structure of the sensing antenna, and the different gas concentration changes were converted into amplitude and frequency changes at different frequency points of the sensing antenna. The test results showed that the sensor operates within the range of carbon dioxide concentration of 600ppm∼1600ppm, with an amplitude change of 10.3dB and a sensitivity of 0.009dB/ppm. The sensitivity of the sensor is 0.29MHz/ppm when operating stably within the ethanol concentration range of 200ppm∼2800ppm. Compared with traditional gas sensors, passive RFID dual parameter gas sensors have the advantages of selective response to carbon dioxide and ethanol gases in mixed gas environments, fast response speed, strong anti-interference to interfering gases, and strong temperature adaptability. It has a good application prospect transportation, agricultural greenhouses, and food testing.

Design and simulation of a highly sensitive photonic crystal fiber sensor for malaria detection

This research focuses on developing an innovative optical sensor utilizing photonic crystal fiber with a unique cladding structure. The photonic crystal fiber’s cladding consists of four layers of circular air holes, with two of them filled with hemoglobin. This arrangement renders the photonic crystal fiber sensitive to changes in hemoglobin concentration, primarily investigating its impact on chromatic dispersion – the wavelength-dependent refractive index variation. The study analyzes two specific wavelengths, 1.2 µm and 1.4 µm, finding high sensitivity at 1.2 µm, calculated to be 0.232 ps/(nm·km)/(g/L). The potential application lies in malaria diagnosis through non-invasive blood sample analysis. We selected the refractive index of an infected red blood cell at the ring stage, setting it at n = 1.395. Our proposed sensor demonstrates outstanding performance in diagnosing malaria at an HGB concentration of 38 g/L at 1.2 µm and at an HGB concentration of 40 g/L at 1.4 µm. By monitoring hemoglobin concentration changes, this photonic crystal fiber-based sensor offers a promising method for early and accurate malaria detection, thus potentially improving global healthcare.

Alkaline hydrothermal cracking effect and substance transformation characteristics of caprolactam-containing sludge

Caprolactam is a crucial chemical intermediate, but its wastewater treatment process generates a significant amount of caprolactam-containing sludge. This study represented the first exploration of the effects of alkaline hydrothermal technology on the cracking and transformation of substances in this sludge. The cracking effect of caprolactam-containing sludge during hydrothermal treatment increased with rising reaction temperature and longer reaction time. With NaOH dosage in hydrothermal treatment increasing from 0 to 2 wt%, the volatile suspended solids (VSS) removal rate of the sludge increased from 44.5% to 74.8%, soluble chemical oxygen demand (SCOD) in the cracking liquid increased from 12772 mg/L to 22976 mg/L, and ammonia nitrogen concentration increased from 398.0 mg/L to 851.2 mg/L. However, the addition of Ca(OH)2 did not significantly affect the changes of sludge suspended solids, VSS and SCOD concentration, but increased the leaching of ammonia nitrogen (up to 745.0 mg/L). This was due to the secondary flocculation of Ca2+, which rebound with dissolved non-proteinaceous organic matter. Increasing temperature, reaction time, and alkaline dosage all enhanced the fluorescence intensity of dissolved organic matter (DOM). Moreover, higher reaction temperature and alkaline dosage reduced the proportion of proteinaceous products in DOM while increasing the proportions of fulvic acids, soluble microbial metabolites, and humic acid-like substances. The study provided crucial theoretical support for engineering application of this technology.

Enhancement of the signal resolution in aptamer assay upon target binding by employing DNA probes and dual fluorophores

In this study, we aimed to significantly enhance the resolution of aptamer assays by using DNA probes and dual fluorophores. The resolution is defined as the smallest change in the target concentration that causes a reliable and distinguishable signal change. Therefore, resolution enhancement in the aptamer assay ensures improved analytical performance. We first examined four aptamer-probe combinations in the aptamer assay and investigated the resolution by observing a percentage signal response difference (% ΔAAD/SYBR). A large % ΔAAD/SYBR means a discernable signal change for a certain concentration difference, which indicates a high-resolution assay. Consequently, significant resolution enhancement (approximately 3–7 times) was achieved using two DNA probes. The improved analytical performance of the resolution-enhanced aptamer assay was further demonstrated by a wide working range of quantification (i.e., 10−2–102 mg/L, four orders of magnitude), a regression curve with improved fitness, and a lower limit of detection (LOD) response (2–6 times lower).

The first-in-human study of QHRD106 functioning as a safe and effective long-acting kallikrein drug potentially aiding ischemic stroke

ABSTRACT Background This study assessed the pharmacokinetics (PK), pharmacodynamics (PD) and safety of QHRD106, and made a comparison with urinary kallindinogenase (UKN) in healthy volunteers. Methods This study comprised a randomized, double-blind, placebo-controlled, single-dose escalation phase and an open-label, multiple-dose escalation phase. 94 subjects received intramuscular injections of QHRD106/placebo only once and 30 subjects received QHRD106 four times. 6 subjects received 0.15 PNA units UKN intravenously for 7 d. PK and PD analysis were conducted by using a electrochemiluminescent assay and a liquid chromatography/mass spectrometry methodology respectively. Cerebral circulation was assessed by the magnetic resonance imaging system. Results QHRD106 exhibited a slow absorption profile in the human body. Compared to UKN, QHRD106 induced changes in bradykinin concentration later, but with a noticeably prolonged duration. Compared to baseline, cerebral blood flow exhibited a significant improvement on d 7 after a single dose of 18,900 IU and an improvement from d 2 to d 14 after multiple dose of 8400 IU of QHRD106. QHRD106 appeared generally good safety and no severe adverse events occurred in all the groups. Conclusions This study provided initial evidence of potential treatment for ischemic strokes that the QHRD106 injection functioned as a safe and effective long-acting kallikrein drug. Registration This study was registered on ClinicalTrials.gov with the identifier NCT06380699 and NCT06388772.

A diet containing mango peel silage impacts upon feed intake, energy supply and growth performances of male dairy calves

The major challenges for disposal of waste from fruit processing factories are high transportation costs, limited landfill availability and environmental pollution. Therefore, developing efficient waste management techniques to reduce transportation costs and environment pollution is important. In 2021, global mango production was estimated to be at 57 million tons and mango peel (MP) represents 7–24% of the whole fruit weight. MP has been considered for use as ruminant feed in the form of fresh, dried, or silage. Fresh MP was abundant during the mango season and high in fermentable carbohydrate, which can easily breakdown and pollute the environment if a proper waste management method is not implemented. Thus, in this study, fresh MP was ensiled after sun-drying for one day and then fed to male dairy calves as a roughage source to evaluate its effect on feed intake, digestibility, energy balance, BW gain, feed efficiency and blood metabolites. Eight growing crossbred weaned male dairy calves (Holstein Friesians × Zebu) were allocated into two groups [Control (n = 4) and mango peel silage (MPS, n = 4)]. This experiment lasted for 12 weeks and calves were housed in 3.0 × 1.5 meters individual pen with concrete floor. Before feeding times, the weights of feed ingredients were weighed and mixed for 15 min. Calves were then given their respective diets ad libitum twice a day, at 0800 and 1600 h. Daily feed offered and refusals were recorded to determine the daily feed intake. A digestion trial was performed over the last five days of the experiment. BW and measurements were recorded every two weeks to determine the weight gain and body physical changes. Blood was collected at the end of experiment to analyze serum biochemical parameters. Ensiling improved the energy and protein content and decreased fiber content of MP, thereby improving the forage quality. Feeding a diet containing MPS at 30% of DM weight, compared to an isonitrogenous Control diet increased (P < 0.05) feed intake, energy supply and energy balance, changes in body measurements, weight gain, feed efficiency, and glucose concentration, as well as lowered (P < 0.05) the blood urea nitrogen concentration of male dairy calves. Ensiling fresh MP after sun-drying for one day led to stable, high-DM silage. Therefore, ensiling fresh MP could improve the feed supply for ruminant production and be an effective waste management strategy for fruit processing businesses.

Particle size distribution shift and diurnal concentration changes of environmental DNA caused by fish spawning behaviour

Particle size distribution shift and diurnal concentration changes of environmental DNA caused by fish spawning behaviour

Design and Testing of a Small-Scale Composting Facility for Sheep Manure Utilizing Aeration and Thermal Treatment

Inner Mongolia has the largest sheep population among China’s provinces, resulting in the production of a substantial amount of sheep manure. If left untreated, this manure can contribute to environmental pollution. However, sheep manure serves a dual purpose: it can be both a pollutant and a valuable source of organic fertilizer. Consequently, there is an urgent need to address the environmental issues arising from manure accumulation and its unused status. In this paper, a viable solution is proposed: the conversion of manure into fertilizer through a composting unit incorporating high-temperature aerobic fermentation technology. This unit, tailored for small farms and individual farmers, integrates critical functions such as ventilation, heating, and turning. Additionally, it boasts excellent thermal insulation, enhancing composting efficiency and enabling precise control over fermentation conditions. This design mitigates heat loss and accelerates maturation, addressing common challenges in traditional composting. The design process encompassed both equipment construction and control systems, with a primary focus on compost fermentation and aeration heating. The components were carefully designed or selected based on theoretical analysis and subsequently validated using simulation software, including EDEM and Fluent. The control system seamlessly integrates a touch screen interface, PLC programming, and control circuits to manage air pumps and electric heaters in response to changes in temperature and oxygen concentration. Furthermore, it controls the motors during the recovery phase. A comprehensive performance evaluation was conducted, revealing notable improvements. Under artificially heated conditions, the maximum temperature of the compost increased by approximately 20 °C, the composting cycle was reduced by roughly 4 days, and the seed germination index (GI) rose by about 9% when compared to natural fermentation. Thus, this device significantly accelerates composting and improves fertilizer quality by increasing the decomposition rate.

Graft-derived cell free DNA: used for assessment of early graft status and its implications for long-term kidney function

BackgroundThe long-term graft survival is closely related to its early status, yet the indices for assessing the early graft status are complex and lack quantitative values. The aim of this study is to investigate the potential of GcfDNA as a comprehensive, non-invasive, convenient, and quantifiable indicator for evaluating early graft status.MethodsIn this study, 138 recipients who underwent primary kidney transplantation were enrolled. Peripheral blood samples, each 10 mL, were collected on days 1 and 7 post-transplantation. The quantification of both the graft cell-free DNA (GcfDNA) fraction (%) and GcfDNA concentration (copies per milliliter, cp/mL) was performed using droplet digital PCR (ddPCR).ResultsFor most recipients, both the GcfDNA fraction and concentration had a rapid decline at 7 days post-transplantation, reaching median values of approximately 0.7% and 53.5 cp/mL, respectively. No significant associations were found between GcfDNA values and other clinical parameters. On the seventh postoperative day, we observed a significant elevation in GcfDNA concentration among recipients with eGFR values &amp;lt; 60 mL/min/1.73 m2. Additionally, notable increases were identified in both GcfDNA fraction and concentration variations within this specific subgroup. The findings of our study indicate a negative correlation between the concentration and fractional changes of GcfDNA on postoperative days 1 and 7, as well as the GcfDNA concentration on postoperative day 7, with eGFR within the 1–2 years post-transplantation period. The ROC curve of GcfDNA_Copies_Variation. day1-day 7 showed the highest AUC value AUC = 0.8006, with high sensitivity (90.14%) and specificity (77.61%), and PPV and NPV were 81.01% and 88.14%, respectively. Using four classical algorithm models, we found that the xgboost regression model achieved the best predictive performance (area under the curve (AUC) values = 0.862) for eGFR within 1–2 years post-transplantation, with high sensitivity (85.7%) and specificity (85%).ConclusionThe changes of GcfDNA levels in the early stage are closely related to kidney function within 1–2 years post-transplantation. As a comprehensive indicator of graft function, GcfDNA has great potential for clinical application.

Formation and Preparation of Herbal Hair Tonic

Today, people are keenly interested in hair preparations and conditioner materials that includes shampoos, hair tonic, and conditioner formulation with herbal extracts. Hair tonic is the product which is used in styling hair. The objective of the present study involved the preparation of herbal hair tonic through the use of jojoba, tulsi, and coconut oil and its evaluation for antifungal and antibacterial activity. The final preparation of these ingredients is formulated in batches with change in concentration. Each formulation is tested for antibacterial and antifungal activity. The formulation of different concentrations was characterized for proximate analysis including moisture content, total ash, acid insoluble ash, water soluble ash, water insoluble ash, sulphated ash. It means for antifungal and antibacterial activity the formulation gives good results, the formulation having good consistency, good spread ability, homogeneity, appearance, and pH.

Prodromal symptoms of a first manic episode: a qualitative study to the perspectives of patients with bipolar disorder and their caregivers'.

Diagnosing bipolar disorder (BD) is challenging, and adequate treatment is of major importance to minimalize the consequences of the illness. Early recognition is one way to address this. Although in clinical research the prodromal phase of BD is gaining interest, the perspective of patients with BD and their caregivers on prodromal symptoms is still lacking. The aim of this study is to gain insights in prodromal symptoms of patients with BD and their caregivers before the onset of a first manic episode. A qualitative research method was used to investigate prodromal symptoms one year prior to a first manic episode. In-depth interviews were conducted with patients with BD type I and their caregivers. Only patients with a first manic episode in the previous five years were included. The prodromal symptoms from patients' and caregivers' perspectives could be clustered into seven themes, with underlying subthemes: behavior (increased activity, destructive behavior, disinhibited behavior, inadequate behavior, changes in appearance), physical changes (changes in sleep, physical signals, differences in facial expression), communication (reciprocity, process, changes in use of social media), thought (process and content), cognition (changes in attention and concentration, forgetfulness), emotions (positive emotions, more intense emotions, mood swings), and personality (more pronounced manifestation of existing personality traits). Patients with bipolar I disorder and their caregivers described subsyndromal manic features one year prior to a first manic episode. In addition, they recognized mood lability, physical changes and more pronounced manifestation of existing personality traits. The results of this study confirm the presence of a prodromal phase. In clinical practice, monitoring of prodromal symptoms of BD can be useful in patients with depression, especially those with a familial risk of BD.

Transportery kwasów tłuszczowych jako potencjalne markery diagnostyczne raka jelita grubego

Colorectal cancer (RJG) is one of the most frequently diagnosed malignant neoplasms: approximately 1.9 million new cases are reported annually. Notwithstanding the advent of techniques for the early detection of RJG and the introduction of novel therapeutic modalities, this disease remains the second leading cause of cancer-related mortality. The results of recent studies highlight the role of fatty acid transporters, including fatty acid translocase/cluster of differentiation 36 (FAT/CD36), fatty acid transport proteins (FATPs), and fatty acid-binding proteins (FABPs), in the pathogenesis of RJG. Changes in serum concentrations and in expression levels in tumor tissue may serve as promising biomarkers for the early diagnosis of the disease and/or the monitoring of its progression and the efficacy of its treatment. Moreover, the fatty acid carriers present a promising avenue for the development of efficacious therapies against RJG.

Cryotherapy with carbon dioxide hydrate enhances immediate recovery of muscle function from neuromuscular fatigue

ABSTRACT This study investigated the effect of cryotherapy with carbon dioxide hydrate (CDH) on fatigue recovery of neuromuscular function and muscle blood circulation. Fourteen young males randomly received three types of 20-min recovery interventions (cryotherapy with CDH [CDH-condition] or normal ice [ICE-condition], or quiet sitting at room temperature [CON-condition]) 5 min following a fatiguing task (50 maximal effort isotonic contractions) on three separate days. The isotonic peak power of the knee extensors at 35 min after the fatiguing task in the CDH-condition (95% of baseline) was greater than that in the other conditions (82–89% of baseline; p ≤ 0.031). In addition, at 25 and 35 min after the fatiguing task, the changes in haemoglobin concentration of the knee extensors from before the fatiguing task in the CON-condition (2.5 and 3.0 μmol/L) were different from those in the ICE-condition (−1.4 and −1.3 μmol/L; p ≤ 0.004) but comparable to those in the CDH-condition (1.1 and 0.7 μmol/L; p ≥ 0.060), respectively. These findings suggest that cryotherapy with CDH did not lower the blood volume following the intervention, unlike that with normal ice, and promoted greater immediate recovery of muscle power from neuromuscular fatigue compared with cryotherapy with ice or passive rest.

Changes in 129I concentration of soil samples after thermal drying.

To precisely evaluate the concentration of iodine-129 (129I) in soil samples, changes in this concentration after thermal drying under several temperature conditions were investigated. The soil sample used in this study was collected from a site located near a nuclear fuel reprocessing plant, which atmospherically released 129I in a test operation in 2006-2008, resulting in the soil sample containing higher 129I concentrations than their natural levels. Thermal drying was conducted from 60°C to 110°C and compared with lyophilization result, showing that the 129I concentration in the soil sample was statistically comparable among all the drying treatments.

Study of seasonal variation of accident-derived atmospheric radiocesium in Koriyama City, Fukushima Prefecture, Japan during 2011-2014.

This study measured the atmospheric concentration and deposition flux of radiocesium in Koriyama City, Fukushima Prefecture, Japan, from November 2011 to October 2014. The results show synchronous seasonal change in atmospheric concentration and deposition flux of radiocesium, which is high during winter to early spring and low during summer to autumn. These seasonal variations are similar to those observed in Fukushima City but differ from those in Namie Town, Fukushima Prefecture, comprising a larger contaminated forest area. The evaluation of the relationship between atmospheric 137Cs concentration or 137Cs specific activity in atmospheric particulate matter (PM) and deposition density of 137Cs in PM source area suggest that stronger winds blowing from areas with relatively large 137Cs deposition (west of Koriyama City) toward the study site affect the site's atmospheric 137Cs concentrations.

Performance evaluation of UKESM1 for surface ozone across the pan-tropics

Abstract. Surface ozone monitoring sites in the tropics are limited, despite the risk that surface ozone poses to human health, tropical forest and crop productivity. Atmospheric chemistry models allow us to assess ozone exposure in unmonitored locations and evaluate the potential influence of changing policies and climate on air quality, human health and ecosystem integrity. Here, we utilise in situ ozone measurements from ground-based stations in the pan-tropics to evaluate ozone from the UK Earth system model, UKESM1, with a focus on remote sites. The study includes ozone data from areas with limited previous data, notably tropical South America, central Africa and tropical northern Australia. Evaluating UKESM1 against observations beginning in 1987 onwards, we show that UKESM1 is able to capture changes in surface ozone concentration at different temporal resolutions, albeit with a systematic high bias of 18.1 nmol mol−1 on average. We use the diurnal ozone range (DOR) as a metric for evaluation and find that UKESM1 captures the observed DOR (mean bias of 2.7 nmol mol−1 and RMSE of 7.1 nmol mol−1) and the trend in DOR with location and season. Results from this study reveal that hourly ozone concentrations from UKESM1 require bias correction before use for impact assessments based on human and ecosystem health. Indeed, hourly surface ozone data have been crucial to this study, and we encourage other modelling groups to include hourly surface ozone output as a default.

Measurements of hydrogen deposition velocities by farmland soil using D2 gas.

Using D2 gas as a substrate, this study investigated the hydrogen deposition velocities of farmland soils around a reprocessing plant located in Rokkasho Village, Aomori, Japan. To determine the hydrogen deposition velocities, closed chambers with fans were set on the soils of farmlands that grow Japanese radishes, and changes in D2 concentration in the chambers were measured by gas chromatography. Results showed hydrogen deposition velocities of six soils were within the range of 1.0×10-4~2.0×10-4ms-1. The heavy water (HDO) formations were detected in the soil after the experiment, showing the oxidation of D2 and conversion to water. Relationships between the obtained hydrogen deposition velocities and environmental conditions such as soil temperature, moisture and porosity were examined. A correlation was found between the hydrogen deposition velocities and soil gas phase rate (r=0.98, p<0.05).

Applicability of reconstruction of temporal changes in 137Cs concentrations in pond water based on the vertical distribution of bottom sediments: a case in three ponds in the Fukushima evacuation zone.

Long-term changes in particulate and dissolved 137Cs concentrations in rivers and dam reservoirs have been reconstructed using 137Cs depth distributions in bottom sediments near Chornobyl and Fukushima. However, few studies have applied this method to pond water. This study tested the applicability of this reconstruction method in ponds within the Fukushima evacuation zone. Bottom sediments in ponds were collected in November 2019. Our reconstruction of a shallow closed pond disagreed with our observations. Even in ponds where the reconstruction agreed well with observations, underestimations may have occurred because the time constant for the decrease in 137Cs concentration was lower than those previously reported. We conclude that the present reconstruction method may be applied to deeper Fukushima ponds with inflow and outflow, but underestimations of initial 137Cs concentrations in water may lead to uncertainties. For realistic reconstruction, attention should be paid to pond characteristics, catchment conditions, and sediment core selection.