Production and uptake of dissolved carbon, nitrogen, and phosphorus in overlying water of aquaculture shrimp ponds in subtropical estuaries, China

Water quality deterioration can adversely affect the long-term sustainability of aquaculture industry. Understanding the processes of nutrient regeneration and uptake is important for improving water quality and the overall ecosystem health of aquaculture system. In spite of the importance of dissolved nutrients (DOC, DIC, N-NO , N-NH , and P-PO ) in governing water quality and ecosystem functioning, the spatiotemporal variations in the production and uptake of dissolved nutrients in aquaculture ponds is still poorly understood. In this study, the nutrient production and uptake rates in the overlying water were quantified among different shrimp growth stages in the aquaculture ponds in the Min River Estuary (MRE) and Jiulong River Estuary (JRE), southeast China. Significant differences in the nutrient production and uptake rates in the overlying water were observed among the three growth stages and two estuaries. The temporal variations of DOC and DIC production rates in both estuarine ponds closely followed the seasonal cycle of temperature, while the difference in DOC and DIC production rates between the two estuaries was likely caused by differences in water salinity. The changes in the production and uptake rates of dissolved inorganic nitrogen (N-NO and N-NH ) and P-PO in the water column over time were partly related to the interactions between thermal conditions and phytoplankton biomass (e.g., chlorophyll a concentrations) in the ponds. Our results demonstrate the complex dynamics and environmental risk of dissolved nutrients in subtropical shrimp ponds, and call for a more effective management of nutrient-laden wastewater in safeguarding the long-term sustainability of aquaculture production

Use of dietary supplements by breast cancer patients undergoing conventional cancer treatment

<b>Background</b> Many breast cancer patients use some form of dietary supplement (DS) to complement their conventional cancer treatment, in the hope that they might lessen the side effects of treatment, improve quality of life, give a greater sense of control, and reduce stress. This pilot study assessed the level of DS usage by breast cancer patients undergoing conventional cancer treatment, and their concerns about the use of DS. <p></p> <b>Method</b> A cross-sectional descriptive survey in three breast cancer centers in Hong Kong using face-to-face interviewing was performed. <p></p> <b>Results</b> Of 82 female Chinese breast cancer patients who completed the survey, 99% reported that they had been using DS since their cancer was diagnosed. The most frequently used DS were Chinese herbal medicines, and patients spent about US$258 on DS every month. The reason given for using DS was to enhance their recovery from cancer, but at the same time the patients had safety concerns. However, most patients did not feel able to discuss these concerns with health professionals. <p></p> <b>Conclusion</b> The majority of the patients had some safety concerns, and said that they would welcome detailed and reliable information on DS. The lack of reliable information on the potential risks and benefits of using such supplements as an adjuvant to conventional treatment and the reluctance of patients to discuss their use of DS with health professionals is a major area of concern that warrants further attention

Large fine‐scale spatiotemporal variations of CH4 diffusive fluxes from shrimp aquaculture ponds affected by organic matter supply and aeration in Southeast China

Mariculture shrimp ponds are important CH4 sources to the atmosphere. However, the spatiotemporal variations of CH4 concentration and flux at fine spatial scales in mariculture ponds are poorly known, particularly in China, worlds largest aquaculture producer. In this study, the plot‐scale spatiotemporal variations of water CH4 concentration and flux, both within and among ponds, were researched in shrimp ponds in Shanyutan wetland, Min River Estuary, Southeast China. The average water CH4 concentration and diffusion flux across the water‐air interface in the shrimp ponds over the shrimp aquaculture period varied from 2.29 ± 0.29 to 50.48 ± 20.91 μM and from 0.09 ± 0.01 to 2.32 ± 0.95 mmol·m−2·hr−1, respectively. The CH4 emissions from the estuarine ponds varied greatly between seasons, with peaks in August and September, which was similar to the trend of water temperature and dissolved oxygen concentrations. There was no remarkable difference in CH4 concentration and flux between shrimp ponds but significantly spatiotemporal differences in CH4 concentration and flux within the ponds. Significantly higher emissions occurred in the feeding zone, accounting for approximately 60% of total CH4 emission flux, while much lower CH4 emissions appeared in aeration zone, contributing 14% to total flux. This study suggests the importance of considering spatiotemporal variation in the whole‐pond estimates of CH4 concentration and flux. In light of such high spatial variation within ponds, improving aeration and feed utilization efficiency would help to mitigate CH4 emissions from mariculture ponds

The relationship between gallbladder status and recurrent biliary complications in patients with choledocholithiasis following endoscopic treatment

AbstractBackgroundEndoscopic methods are currently the treatment of choice for patients with common bile duct (CBD) stones, but subsequent management of the intact gallbladder for patients following endoscopic treatment is still controversial. The primary aim of this study was to discover the association between gallbladder status and recurrent biliary complications for patients with CBD stones after endoscopic treatment. Additionally, we also sought to determine risk factors for recurrent biliary complications in these patients.MethodsThe records of 1625 patients with CBD stones following endoscopic treatment were reviewed. A total of 681 patients were enrolled and subsequently categorized into four groups: Group 1 (n = 201), calculous gallbladder; Group 2 (n = 140), acalculous gallbladder; Group 3 (n = 175), elective cholecystectomy after endoscopic treatment; and Group 4 (n = 165), prior cholecystectomy. The basic demographics and recurrent biliary complications during follow-up among these four groups were analyzed by Chi-square test, ANOVA, Kaplan-Meier analysis, and log-rank test.ResultsDuring the median follow-up period of 34 months, 133 patients (20%) with recurrent biliary complications were identified. The recurrence rates of Groups 1, 2, 3, and 4 were 29%, 11%, 15%, and 19%, respectively. Kaplan-Meier analysis showed that patients with calculous gallbladder had a significantly higher rate of recurrent biliary complication. In multivariate analysis, patients with a history of cirrhosis, juxta-papillary diverticulum, calculous gallbladder, CBD size ≥1.5 cm, and endoscopic management with endoscopic sphincterotomy were at a higher risk for developing biliary complications (p = 0.029, p = 0.039, p < 0.001, p = 0.002, p = 0.021, respectively.)ConclusionPatients with cholecystolithiasis and CBD stones had a higher incidence of recurrent biliary complications. For some of these patients, elective cholecystectomy following endoscopic treatment may be considered. However, routine elective cholecystectomy in patients with normal gallbladder is not appropriate because of the low recurrence of biliary complications. Whether gallbladder function affects the biliary clearance and biliary complications requires further research

Quantitative Model for the Surface-related Electron Transfer in CdS Quantum Dots

The influence of surface S2- dangling bonds and surface doped ions(Se2-, Cu2+, and Hg2+) on the photoluminescence of Cd2+-rich CdS QDs was investigated. A quantitative model was proposed to understand the complex transfer processes of excited electrons in CdS QDs. The transfer of excited electrons from either the conduction band or the Cd2+-related trap-state to the surface S2--related shallow hole trap-state is effective. However, the trap of excited electrons by surface doped ion trap-states from the Cd2+-related trap-state is more effective than that from the conduction band. The efficiency of trapping electrons from both the conduction band and the Cd2+-related trap-state can be quantitatively understood with the help of the proposed model. The results show that the transfer efficiency of excited electrons is dependent on the location of the energy-level of the relevant surface-related trap-state. The trap of excited electrons by the surface trap-state with energy-level closer to that of the conduction band is more effective, especially for the trap of excited electrons from Cd2+-related trap-state.Measurement and Testing Center of Zhejiang Province, China [02079

Photoresponse of polyaniline-functionalized graphene quantum dots

Polyaniline-functionalized graphene quantum dots (PANI-GQD) and pristine graphene quantum dots (GQDs) were utilized for optoelectronic devices. The PANI-GQD based photodetector exhibited higher responsivity which is about an order of magnitude at 405 nm and 7 folds at 532 nm as compared to GQD-based photodetectors. The improved photoresponse is attributed to the enhanced interconnection of GQD by island-like polymer matrices, which facilitate carrier transport within the polymer matrices. The optically tunable current–voltage (I–V) hysteresis of PANI-GQD was also demonstrated. The hysteresis magnifies progressively with light intensity at a scan range of ±1 V. Both GQD and PANI-GQD devices change from positive to negative photocurrent when the bias reaches 4 V. Photogenerated carriers are excited to the trapping states in GQDs with increased bias. The trapped charges interact with charges injected from the electrodes which results in a net decrease of free charge carriers and a negative photocurrent. The photocurrent switching phenomenon in GQD and PANI-GQD devices may open up novel applications in optoelectronics

Behavioral Evidence and Olfactory Reception of a Single Alarm Pheromone Component in Halyomorpha halys

Halyomorpha halys is a major herbivore insect in the fruit orchards of China that has become a devastating invasive pest in North America and Europe since its accidental introductions in the 1990s and 2000s, respectively. Like other hemipteran insects, H. halys releases defensive chemicals against natural enemies, including (E)-2-decenal, which is an aldehyde associated with alarm pheromones. In this study, a series of electrophysiological and behavioral tests were conducted to characterize the alarm functions of (E)-2-decenal among H. halys adults and nymphs. An antennal transcriptome was obtained from a Chinese H. halys population, and 44 odorant-binding protein (OBP) genes were annotated. Among them, five putative alarm pheromone-binding proteins were screened and were extremely consistent with their homologs from US populations. These five OBPs were later expressed in a heterologous expression system, harvested, and then challenged with (E)-2-decenal in a binding assay. All five OBPs showed high binding activities to (E)-2-decenal, which demonstrated its behavioral significance as a defensive component in H. halys, as well as being the first report of its olfactory reception. These findings will help develop behavioral-mediating tools as part of integrated pest management approaches to control this invasive pest