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Early prediction of breast cancer based on the classification of HER-2 and ER Biomark...
Saranyaraj D
MANIKANDAN M

Saranyaraj D

and 1 more

February 10, 2023
Background: Due to the highly coarse chromatin, multi-dimensionality of the histo image, irregularity of shape and size, texture, and appearance, nuclei extraction is challenging. To address these complexities, a deep learning algorithm called a stacked sparse autoencoder had been considered a research factor in this paper. Methods and Material: This paper focuses on detecting the epithelial regions and extracting high-level features to segment the patches based on the nuclei and classify the biomarkers concerning the nuclei patches. We used 6,53,400 microscopic image patches of 363 patients sourced from the BreakHis database, of which 4,90,050 prominent image patches containing only nuclei were utilized for Biomarker classification (Basically eliminating the non-nuclei patches from 363 Whole slide Images (WSI)). The non-nuclei patches were eliminated due to imbalanced class distribution. Results: The classifier finally classifies if the nuclei detected based on the features are benign or malignant, or normal with an accuracy of 99.73%, using which the early prediction is performed by extracting and classifying the biomarkers HER2 and ER. The overall classification rate of classifying HER-2 and ER is 97.52%. Conclusion: The HER2 +ve was classified with intensity above 23%, and Total nuclei in the range 150-1000 are termed ER positive. Based on these 40 patients with HER2 +ve and 25 patients with ER +ve were detected out of 363 patients. From the observation, it is concluded that 25-40 patients are risked of breast cancer in the next 5 years due to the cell proliferation rate of 7000.
Post-Marketing Safety Concerns with Nirmatrelvir: A Disproportionality Analysis of Sp...
Wei Zhuang
Jiabing Xu

Wei Zhuang

and 8 more

February 10, 2023
Aim: Nirmatrelvir as a new 3CL protease inhibitor for treating COVID-19 drug of antiviral drug, the potential side effects have not yet been fully studied yet. The aim of this study was to identify potential risk of Nirmatrelvir by analyzing post-marketing safety data based on the largest publicly available worldwide pharmacovigilance database. Methods: We analyzed Nirmatrelvir adverse events to detect and characterize relevant safety signals based on the FDA Adverse Event Reporting System database in 2022. Case/non-case approach were used to estimate the reporting odds ratio (ROR) and information component (IC) with relevant confidence intervals (95% CI) for AEs with ≥4 counts. Results: Total of 26846 cases were included. Disease recurrence [ROR(95%CI)=413.2(395.6-431.59)], dysgeusia [ROR(95%CI)=110.84(106.04-115.85)], anosmia [ROR(95%CI)=15.21(12.76-18.11)], ageusia [ROR(95%CI)=9.80(8.50-11.3)] and urticaria [ROR(95%CI)=1.91(1.69-2.17)] were the main safety signals. In addition, abdominal pain upper and skin toxicity were two specific safety signals of Nirmatrelvir. In pregnant population, a significant increased ROR was found in life-threatening [ROR(95%CI)=5.12(1.38-19.00)]. Conclusion: We identified that disease recurrence, dysgeusia, abdominal pain upper and skin toxicity were the main and specific safety signals of Nirmatrelvir. Clinician and pharmacist should pay attention on these AEs. Notably, a potential risk of Nirmatrelvir in pregnant population should be alerted.
Investigation of women’s access to cervical cancer screening during the Covid-19 pand...
Nuran GENCTURK
Nilay Şener Özovalı

Nuran GENCTURK

and 1 more

February 10, 2023
Objectives: Covid-19, which affected countries all over the world have disrupted health services and cancer screenings worldwide. The study aimed to determine women’s access to cervical cancer screening during the Covid-19 pandemic in Turkiye. Methods: The study was planned as a descriptive cross-sectional. This study was composed of women who have been sexually active. This study was completed with 443 people. The data were collected between 19 March and 27 April 2021 using the “Data Collection Form” and the “Attitudes Towards Prevention of Cervical Cancer Scale”. Results: More than half of the women stated that Covid-19 and pandemic restrictions did not affect their pap-smear. However, the Attitudes Towards Prevention of Cervical Cancer Scale Cognitive and Affective mean scores of the women who stated that the pandemic restrictions did not affect her getting pap-smear were lower than the women who stated that it did. This situation shows that the attitudes of women who stated that pandemic restrictions do not affect their pap smears have low attitudes towards protection from cervical cancer. Conclusions: It has been found that the Covid-19 pandemic and the restrictions in accessing the health services related to the pandemic have an impact on the attitudes towards protection from cervical cancer, such as having a pap smear. Relevance to clinical practice: Considering the unprecedented effects of the pandemic around the world, in order to avoid its negative effects on cancer screenings, health professionals working in public health services should not delay cervical cancer screening tests.
Seasonal timing of ecosystem linkage contributes to maintaining life-history variatio...
Rui Ueda
Minoru Kanaiwa

Rui Ueda

and 4 more

February 10, 2023
Life-history variation can contribute to long-term persistence of populations, but it remains unknown what ecosystem properties maintain life-history variation within a population. Seasonally recurring resource subsidies are common in nature, but human-induced environmental changes, including global climate change, are causing temporal shifts and decline in those subsidies. We experimentally demonstrated that the terrestrial invertebrate subsidy occurring early in a growing season facilitated red-spotted masu salmon individuals to adopt a fast life, while the early-subsidy also maintained individuals that adopted a slow life. In contrast, the late-subsidy did not increase the fast-life individuals as much as the early-subsidy did. Consequently, the life-history variation was higher in the early-subsidy treatment than in late-subsidy treatment and no-subsidy control. The variation in life-history was not simply explained by the growth-survival trade-off. These results highlight the role of seasonal ecosystem linkages in maintaining life-history variation within a population and securing population stability at land-scape scale.
Renal Dysfunction Determinants in Advanced Heart Failure Patients: Pulmonary Artery C...
Emre Demir
Aytaç Candemir

Emre Demir

and 7 more

February 10, 2023
Introduction: Renal dysfunction in heart failure (HF) patients is associated with poor outcomes. Reduced cardiac index (CI) and right atrial pressure (RAP) are postulated to be a contributor the renal dysfunction. This study aimed to investigate the relationship between the estimated glomerular filtration rate (eGFR) and the pulmonary artery catheterization (PAC) results. Patients and Method: Hospitalized advanced HF patients, between 2016-2020 PAC performed included in the study. Renal dysfunction was defined as eGFR<60 ml/min/1.73 m 2. We evaluated the correlation and the linear regression models of hemodynamics with eGFR. Results: 181 patients were included in the study, and the mean left ventricular ejection fraction (LVEF) was 20.9±3.7%, the mean eGFR was 79.8±25.4 ml/min/1.73 m 2, and 22.7% of patients had eGFR lower than 60 ml/min/1.73 m 2. CI (1.85±0.72; 1.84±0.64; p=0.47, respectively) and RAP (13.1±6.6; 13.7±6.8; p=0.61,respectively) was not significantly associated with renal dysfunction in HF patients. In the multivariable model, smoking history, AF, body mass index (BMI) revealed negative relation with eGFR, continuing ACEi or ARB therapy, and pulmonary artery capacitance index(PAC-i) were positively related variables with eGFR (p<0.0001). eGFR was not significantly different in distinct tricuspid regurgitation severities (p=0.67); however, eGFR was non-significantly higher in patients with moderate tricuspid regurgitation. In patients with moderate tricuspid regurgitation, eGFR had an inverse relationship with the RVSW-i and TRVP-i. Conclusion: These results indicate that CI or RAP is not the primary driver for eGFR. PAC-i and continuing ACEi or ARB positively, AF, smoking history, and BMI were negatively related factors for reduced eGFR.
Application and development of Construction Robot
朋昊 李
Yubing Hu

朋昊 李

and 3 more

January 30, 2023
Introduction With the rapid acceleration of the economic construction,the recent years have witnessed a huge development in the building industry. Based on the characteristics of the building industry,the technology of industrial robot has been introduced and the development of building robots has become an inevitable trend with pertinences. Methods In combination with the aspects of mechanical structure and control system and so on,the present situation of application and study of wall construction robots,decoration construction robots,maintenance construction robots,rescue construction robots and 3D printing construction robots at home and abroad are systematically reviewed in this paper.At the same time,from the aspects of structure design,sensor technology,navigation & positioning technology and control system and so on. Conclusion out the future developmental direction of building robotics–integrating high-precision, lightweight design, intelligence and other features.
Movement patterns and predator-prey interactions of domestic Atlantic salmon (Salmo...
Michael Lawrence

Michael Lawrence

and 10 more

February 13, 2023
A document by Michael Lawrence. Click on the document to view its contents.
Prospects for rice in 2050
Jianxin Shi
Gynheung An

Jianxin Shi

and 3 more

February 10, 2023
A key to achieve the goals put forward in the UN's 2030 Agenda for Sustainable Development, it will need transformative change to our agrifood systems. We must mount to the global challenge to achieve food security in a sustainable manner in the context of climate change, population growth, urbanization, and depletion of natural resources. Rice is one of the major staple cereal crops that has contributed, is contributing, and will still contribute to the global food security. To date, rice yield has held pace with increasing demands, due to advances in both fundamental and biological studies, as well as genomic and molecular breeding practices. However, future rice production depends largely on the planting of resilient cultivars that can acclimate and adapt to changing environmental conditions. This Special Issue highlight with reviews and original research articles the exciting and growing field of rice-environment interactions that could benefit future rice breeding. We also outline open questions and propose future directions of 2050 rice research, calling for more attentions to develop environment resilient rice especially hybrid rice, upland rice and perennial rice.
THE EFFECT OF MELATONIN ON SOME PHYSIOLOGICAL PARAMETERS, SALT SENSOR GENES AND DNA M...
Mahmut Sinan Taspinar
Meryem Kukara

Mahmut Sinan Taspinar

and 3 more

February 10, 2023
Salinity, an important abiotic stress, affects arable land worldwide, reducing crop growth, yield and quality. Lettuce ( Lactuca sativa L.), which is very sensitive to salt stress, is one of the crops affected by soil salinity and salt (NaCl) stress also affects lettuce cultivation. Different plant growth regulators (salicylic acid (SA), polyamines, glycine betaine (GB) and melatonin (MEL)) are used to reduce the harmful effects of soil salinity. In this study, the effects of NaCl and MEL treatments on physiological parameters (cell membrane damage (%), leaf relative water content (RWC%), chlorophyll amount), DNA methylation and some NaCl tolerance genes ( SOS1, SOS2, AKT1, NHX1, HKT1) have examined in two different lettuce genotypes (Yedikule and Ivanka). When the effect of NaCl stress on physiological parameters was examined, it was detected that this stress increased cell membrane damage and decreased chlorophyll content and RWC %. The effects of MEL applications together with NaCl stress on these parameters were positive. In the gene expression analysis results, it was determined that SOS1, SOS2, AKT1, NHX1 and HKT1 gene expressions increased in both lettuce genotypes and decreased in MEL applications. On the flip side, according to methylation sensitive amplification polymorphism (MSAP) findings, while a decrease in methylation level was determined in NaCl stress compared to the control in both genotypes. Methylation levels increased compared to NaCl stress in MEL applications with NaCl stress, but this rate was still lower than the control. According to the results obtained, it was concluded that exogenous MEL application in lettuce genotypes is important in response to NaCl stress.
Effects of Typical Broad-leaved and Coniferous Forests on Water Quality in the Qinlin...
Shengli Zhang
Xiaoxiao Gao

Shengli Zhang

and 1 more

February 10, 2023
Forests in the Qinling Mountains are an important source of fresh water for 34.68 million people in China. However, heavy metal pollution and acid rain have recently become common in this region. Forests can improve water quality; however, a large amount of the Qinling Mountains is covered by poor quality vegetation. This study investigated the effects of Quercus aliena var . Acuteserrata (Qa), Pinus tabulaeformis (Pt), Pinus armandii (Pa), and mixed broad-leaved (Mb) tree stands on water quality in this region. The results showed that the four stands increased the pH of slightly acidic rainfall; this effect was more pronounced in broad-leaved stands than in coniferous stands. As rainfall was converted to interflow, which is the most important type of runoff in natural forest, the average SO 4 2- concentrations in broad-leaved stands were higher in soil horizon A and lower in soil horizon B compared to coniferous stands. As rainfall passed through the trees, average NO 3 - concentrations increased whereas NH 4 + decreased. Compared to coniferous stands, NO 3 - and NH 4 + concentrations in soil horizon A interflow were higher in broad-leaved stands whereas NH 4 + concentrations were lower in soil horizon B. Average Cd and Pb concentrations decreased remarkably as rainfall flowed through the stands. Broad-leaved stands led to greater Cd reduction than coniferous stands. Furthermore, the Mb stand led to the greatest reduction in Pb concentration. These results will be useful for selecting the most appropriate tree species for afforestation in [water-source](app:ds:forest%20for%20water%20resource%20conservation) regions and in similar areas experiencing air pollution, specifically heavy metal pollution.
Emerging Pteropine orthoreoviruses and their potential impact on public health
Hinh Ly
Widaliz Vega-Rodriguez

Hinh Ly

and 1 more

February 10, 2023
A group of viruses, collectively known as Pteropine orthoreoviruses (PRVs), have recently been found in fruit bats and humans in Southeast Asia, Australia, and some African countries. This article intends to briefly discuss what is known about these viruses and their potential significance in public health and to advocate for increased surveillance of these zoonotic viruses to prevent potential future disease outbreaks, as well as to highlight a recent publication on this topic that was selected as an editor’s choice article in the Journal of Medical Virology 1.
An Evidence of Drug Repurposing for COVID-19 Pandemic Based on In silico Investigatio...
Swaraj Mohanty
Soumya Lipsa Rath

Swaraj Mohanty

and 3 more

July 10, 2023
A document by Yasmin Ahmad. Click on the document to view its contents.
How to differentiate between invasive lobular carcinoma metastasis and type 4 advance...
Ryuhei Jinushi
Tomonori Kawasaki

Ryuhei Jinushi

and 2 more

February 10, 2023
Gastric metastases originating from breast carcinomas and type 4 advanced gastric cancers are often difficult to distinguish because of their similar endoscopic and pathologic characteristics. This often delays early intervention and accordingly affects prognosis. Immunohistochemical analyses are important for both diagnosis and treatment of breast carcinomas.
Primary scrotal Lipoma posing a diagnostic quandary: Experience from Northern Tanzani...
Orgeness Mbwambo
Angela Pallangyo

Orgeness Mbwambo

and 6 more

February 10, 2023
Primary scrotal lipoma is a rare urological diagnosis. It is usually diagnosed incidentally as most of time initial diagnosis may be confused with other common etiology of scrotal masses. Here, we present a case a rare case of scrotal lipoma with initial misdiagnosis of hydrocele at primary health facility.
Numerical investigation of an enhanced PTC absorber tube using cylindrical inserts.
Mohammed Reda HADDOUCHE

Mohammed Reda HADDOUCHE

February 10, 2023
The main purpose of this study is to investigate numerically the thermal performance of a parabolic trough solar collector’s absorber tube that contains a novel kind of inserts with the objective to improve the heat transfer between the heat transfer fluid and the absorber tube. In the first part of this paper, the diameter and the length of the cylindrical inserts are investigated based on Finite Volume Method and Monte Carlo Ray Tracing method for Reynolds number ranges from 2 . 36 ∙ 10 4 to 7 . 09 ∙ 10 4 . In the second part, the eccentricity of the cylindrical inserts is investigated under the same operating conditions. The Therminol ®VP1 is the HTF that used in this investigation intermediate fluid. The numerical simulation indicates that the perturbators enhance the thermal behavior of receiver and reduces the absorber tube’s temperature difference.
Cellular redox state affects biofilm formation by a surfactin -dependent manner in Ba...
Huiwan Sun
Fengmei Si

Huiwan Sun

and 3 more

February 10, 2023
Surfactin is a signal to trigger biofilm formation against harsh environments. Generally, harsh environments can result in change of the cellular redox state to induce biofilm formation, but we know little about whether the cellular redox state influences biofilm formation via surfactin. Here, the reductant glucose could reduce surfactin and enhance biofilm formation by a surfactin-independent way. The oxidant H2O2 led to a decrease of surfactin accompanying with weakened biofilm formation. Spx and PerR were both necessary for surfactin production and biofilm formation. H2O2 improved surfactin production but inhibited biofilm formation by a surfactin-independent manner in Δspx, while it reduced surfactin production without obvious influence on biofilm formation in ΔperR. The ability against H2O2 stress was enhanced in Δspx, but weakened in ΔperR. Thereby, PerR was favorable for resisting oxidative stress, while Spx played a negative role in this action. Knockout and compensation of rex also supported that the cells could form biofilm by a surfactin-independent way. Collectively, surfactin is not a unique signal to trigger biofilm formation, and the cellular redox state can influence biofilm formation by a surfactin- dependent or independent way in B. amyloliquefaciens.
Diversity of pathogenic bacteria and incidence of antibiotic resistant genes in water...
Alfrick Makori
Johnstone Neondo

Alfrick Makori

and 3 more

February 10, 2023
Water used in eateries is a potential reservoir for acquisition and dissemination of antibiotic resistance, and human exposure to antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in drinking water may pose an additional health risk. Antimicrobial resistome monitoring is currently not a routine standard check of drinking water by health sector in developing countries. In the present study, culture dependent and illumina sequencing techniques profiled the occurrence of rich bacterial genetic diversity and resistome conundrum in water used by eateries in selected open markets. Analyses were done using R software and QIIME2 software. Heatmap outputs exhibited the correlation contours of morphological, biochemical, antibiotic susceptibility and antibiotic resistance genes (ARG) of culturable bacteria. Results show the following prevalent genera per sampled site; Wakulima Eateries ( Acinetobacter 44.180%), Wakulima Open Market ( Duganella 28.201%), Gashororo Eateries ( Acinetobacter 15.189%), Gashororo Open Market ( Acinetobacter 30.675%) Mwerevu Eateries ( Acinetobacter 40.823%) and Mwerevu Open Markets ( Curvibacter 48.785%). The qnrD and sul2 ARGs were detected in all six samples, int1 and FloR were present in five samples while strB, catA and blaTEM were detected in single sample using qualitative PCR. These findings form critical reference data for development of bacterial pathogen surveillance toolkit in the area.
Acute Calcific Periarthritis of Acromioclavicular Joint: A Case Report
Shila Awal
Nabaraj Acharya

Shila Awal

and 5 more

February 10, 2023
Deposition of hydroxyapatite crystals in the para-articular soft tissues is a well-known condition. However, this condition has been rarely described in acromioclavicular joint . We report a case of 55 year gentleman, presented with acute onset of shoulder pain , who was diagnosed with calcific periarthritis of acromioclavicular joint.
Utilization of spent coffee grounds as fillers to prepare polypropylene composites fo...
Yurong Cai
Wenmin Song

Yurong Cai

and 6 more

February 10, 2023
Biomass-derived wastes as the additive of non-degradable plastics have been paid more attention due to the ever-growing environmental pollution and energy crisis. Herein, the spent coffee grounds (SCG) have been used as fillers in polypropylene (PP) after the heat treatment to realize its recycling utilization. The effect of the heat treatment atmosphere on the properties of the obtained SCG and SCG/PP composites has been investigated systematically. The results show that the residual coffee oil can be removed more thoroughly under an air atmosphere than under a nitrogen atmosphere at a relatively low cost and an eco-friendly process. The lower residual oil rate of SCG is beneficial to improve the comminution and further enhance the affinity with the PP matrix. The obtained SCG/PP composite holds lower water absorption, higher hydrophobicity, and better mechanical properties, implying its potential applications in the field of food packaging.
Mimicry in misophonia: A large-scale survey of prevalence and relationship with trigg...
Paris Arizona Ash
Ester Benzaquén

Paris Arizona Ash

and 4 more

February 10, 2023
Background Misophonia is often characterized by excessive negative emotional responses, including anger and anxiety, to “trigger sounds” which are typically day-to-day sounds, such as those generated from people eating. Misophonia (literally ‘hatred of sounds’) has commonly been understood within an auditory processing framework where sounds cause distress due to aberrant processing in the auditory and emotional systems of the brain. However, recent evidence from brain imaging shows involvement of the motor system while listening to trigger sounds suggesting that the perception of an action (e.g., mouth movement) produced by a trigger person, not the sound per se, drives distress in misophonia. Observation or listening to sounds of another’s actions are known to prompt automatic mimicry/imitations. Apart from anecdotal evidence and a few case studies, a relationship between mimicry and misophonia has not been evaluated. Method We addressed this ‘gap’ by collecting data on misophonia symptoms and mimicry behaviour using online questionnaires from 676 participants. Results The analysis shows, (i) the tendency to mimic varies in direct proportion to misophonia severity assessed using a self-reported questionnaire, (ii) compared to other human and environmental sounds, trigger sounds of eating and chewing are more likely to trigger mimicking, and (iii) the act of mimicking provides relief from distress to most people with misophonia. Conclusion Mimicry is widely prevalent in misophonia and is elicited by the most common trigger sounds of eating. The data provides support to the model that misophonia is not a disorder of sound-processing but rather its basis lies in social perception.
The Aversiveness of Intrusiveness: Evidence from Involuntary Musical Imagery
Aviv Akerman-Nathan
Hadar Naftalovich

Aviv Akerman-Nathan

and 2 more

February 10, 2023
Objective: Intrusive thoughts are characterized by a sense of intrusiveness of foreign entry into cognition. While not always consisting of negative content, intrusive thoughts are almost solely investigated in that context. Involuntary Musical Imagery (INMI) offers a promising alternative, as it is a type of involuntary cognition that can be used to evaluate intrusiveness without negative content. Methos: In Study 1, 200 participants completed self-report questionnaires to assess several aspects of intrusiveness: meta-awareness, control, repetitiveness, frequency, and subjective experience of INMI. In Study 2, 203 participants completed self-report questionnaires to explore the clinical characteristics (depression, stress, anxiety, and rumination) which might mediate the connection between INMI frequency and INMI negative experience. Results: Study 1 revealed, through exploratory factor analysis, that intrusiveness shares variance with the negative experience of INMI but not with INMI frequency. In study 2, ruminative thinking was found to mediate the relationship between frequent INMI and negative experience of INMI. Conclusion: These results suggest that INMI might be used to investigate intrusiveness in the lab without the potential confound of negative emotions. In addition, the results suggest that neither the content nor the frequency of intrusive thoughts can solely explain why these thoughts are aversive to some but not others. Ruminative style might be the missing link to explain how and why these intrusive thoughts become aversive and obsessive. In other words, we suggest that the cause for intrusiveness lies not in the thought or repetitiveness, but in the thinker.
The role of social support and dysfunctional attitude to determine the level of menta...
Tewodros Weldemedin

Tewodros Weldemedin

February 10, 2023
The prevalence of mental distress is higher among university students, and mental health disturbances are expected to rise amid significant social crises such as war. First-year students who enrolled in university programs after higher education institutions reopened in the midst of ongoing armed conflict face greater mental distress as they adjust to university life and deal with the aftermath of war. Therefore, this study aimed to investigate the prevalence of depression, anxiety, and stress and the predictive roles of social support and dysfunctional attitudes to determine the level of mental distress among students. A cross-sectional survey study was conducted among 335 first-year students at the University of Gondar. A multistage sampling technique was used to enroll participants. Data were collected using the depression, anxiety, and stress scale (DASS-21), the short version of the dysfunctional attitude scale, and the multidimensional scale for perceived social support (MSPSS). To determine the prevalence, descriptive analysis was used, followed by a t-test to compare gender differences and multiple regression analysis to examine associated factors. The sample comprised 56.4% of male respondents, and the mean age was 19.93. (SD: 1.28). Depression, anxiety, and stress were prevalent among 72.8%, 69.3%, and 57.3% of the participants, respectively. While sleep and appetite problems were strongly associated with depression, anxiety, and stress, previous mental disorder diagnoses and fear of poor grades only significantly correlated with depression and anxiety. Excessive internet use, on the other hand, was correlated with increased anxiety levels. Multiple regression analysis revealed that social support and dysfunctional attitudes explained 21% of the difference in students’ levels of depression, anxiety, and stress. Social support was the strongest predictor across all diagnoses. In conclusion, a high prevalence of depression, anxiety, and stress was reported among students, and the level of social support received was found to be the strongest predictor. Therefore, interventions aimed at expanding students’ social networks and access to social support are recommended.
Lakes-scale pattern of eukaryotic phytoplankton diversity and assembly process shaped...
Huan Zhu
Xiong Xiong

Huan Zhu

and 2 more

February 10, 2023
Phytoplankton are the main primary producers in aquatic ecosystems and play an important role in food web and geochemical cycles. Its diversity, community structure, and assembly process are influenced by several factors. Among these factors, climate change and human synergistic changes in water physicochemical factors and nutrient levels are the main causes. Alpine lake ecosystems are relatively weak and extremely sensitive to global climate change. However, the impact of climate change on phytoplankton in Qinghai-Tibet Plateau (QTP) lakes and their responses are still unclear. In this study, we systematically analyzed the diversity, environmental drivers, and assembly process of phytoplankton community in the central QTP lakes. The phytoplankton of these lakes can be primarily distinguished into freshwater and brackish types, with significant differences in species diversity and community dissimilarity. Both types shared nearly same key environmental factors that significantly affecting phytoplankton such as EC, and brackish lakes were also positively correlative with TN, Ca and Si. Stochastic process was predominant in phytoplankton assembly because of the harsh environmental condition. Additionally, freshwater and brackish lakes were dominated by dispersal limitation and heterogeneous selection respectively. Alpine lakes had significant EC thresholds, and their diversity and assembly processes changed significantly around the thresholds. Owing to warming and moistening of QTP during the past decades, some significant changes have occurred, such as gradual decrease in lake EC. The present findings have important implications for understanding and predicting the response of lake phytoplankton communities to climate change and for making decisions to protect the ecological resources of alpine lakes.
Polythiophene Derivatives Carbonized Polymer Dots:Aggregation Induced Solid-state Flu...
Jian Li
Fanghao Zhao

Jian Li

and 10 more

February 10, 2023
Currently, solid-state fluorescent carbonized polymer dots (CPDs) have attracted attention increasingly due to their applications for op-toelectronic display. However, designing CPDs possessing solid-state fluorescence and clarifying the fluorescence mechanism still remain challenging. Herein, we initially synthesized a novel type of polythiophene derivatives CPDs, poly-4,4’-(thiophene-3,4-diyl)dibenzoic acid carbonized polymer dots (PDBA-CPDs) with solid-state fluorescence. Subsequently, the structural and optical characterization re-vealed that solid-state fluorescence originating from the aggregation induced emission of the CPDs. In brief, in aggregation state, the remaining polymer structure groups on the surface of the CPDs overlapped and weakened the non-radiative transition, enhancing sol-id-state fluorescence emission. Thirdly, three polythiophene-derived CPDs were designed to further demonstrate the aggregation in-duced solid-state fluorescence mechanism. Finally, owing to their unique properties of solid-state fluorescence, the white LEDs (light emitting diodes) were fabricated with high color rendering index (CRI) of 82.7 and CIE coordinates of (0.37, 0.39) using commercial 460 nm chip. This work facilitates the development of CPDs’ solid-state fluorescence mechanisms and advances the application of CPDs in the field of optoelectronics.
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