Design of the electron cyclotron resonance (ECR) plasma source for the space plasma environment research facility.

The Space Plasma Environment Research Facility (SPERF) was built in Harbin to study the three-dimensional magnetic reconnection and wave-particle interactions relevant to space physics in laboratory settings. A 2.45 GHz Electron Cyclotron Resonance (ECR) plasma source is adopted in the device to simulate the Earth's magnetosphere and achieve the scientific goals. In this paper, the design of the ECR plasma source is presented. The structures of the microwave source, the microwave transfer system, and the antenna are introduced. Additionally, the resonant surfaces are computed to predict the locations of microwave absorption. The absorption mechanisms of the microwave in the SPERF are also discussed. The discharge experiment demonstrates the utility of the ECR source in simulating the Earth's magnetosphere. The successful operation of the source indicates that the ECR discharge is a powerful tool for creating a plasma environment in a large plasma experimental device.

Effects of ferritin heavy chain on oxidative stress, cell proliferation and apoptosis in geese follicular granulosa cells.

1. The ferritin heavy chain (FHC) has a vital impact on follicular development in geese, due to its ability to regulate apoptosis of granulosa cells (GCs) and follicular atresia. However, its specific regulatory mechanisms remain unclear. The present study characterised how FHC regulates oxidative stress, cell proliferation and apoptosis in goose GCs by interfering with and overexpressing the FHC gene.2. After 72 h of interference with FHC expression, the activity of GCs decreased remarkably (p < 0.05), reactive oxygen species (ROS) levels and the expression levels of antioxidant enzyme genes catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) increased significantly (p < 0.05). The overexpression of FHC for 72 h was found to significantly reduce the expression of CAT and SOD genes (p < 0.05).3. Interfering with FHC expression revealed that the expression levels of the cell proliferation gene Aurora kinase A (AURORA-A) were significantly decreased (p < 0.05), while the expression levels of the apoptosis genes B-cell lymphoma-2 (BCL-2) and cysteine aspartate-specific protease 8 (CASPASE 8) increased (p < 0.05). Further research has shown that, when interfering with FHC expression for 72 h, apoptosis rate increased by 1.19-fold (p < 0.05), but the current data showed a lower apoptosis rate after FHC overexpression by 59.41%, 63.39%, and 52.31% at three different treatment times (p < 0.05).4. In conclusion, FHC improved the antioxidant capacity of GCs, promotes GCs proliferation, and inhibits GCs apoptosis of ovarian follicles in Sichuan white geese.

Historical Trends and Future Projections of Demand for Permanent Residential Aged Care for Older People in Australia, 2008-2052.

OBJECTIVES: To examine the historical trends and predict the future rates and total volumes of permanent residential aged care (PRAC) service utilization in Australia. DESIGN: A population-based repeated cross-sectional and projection study of non-indigenous older people (≥65 years) accessing PRAC in Australia was conducted. SETTING AND PARTICIPANTS: Publicly available aged care admissions from the Australian Institute of Health and Welfare and population estimates from the Australian Bureau of Statistics were used. METHODS: Historical incidence rates (per 1000 people), incidence rate ratios (IRRs) and 95% CIs of PRAC admission from 2008-2009 to 2020-2021 were estimated using negative binomial regression models. The future incidence and prediction intervals (PIs) of PRAC admission between 2021-2022 and 2051-2052 were projected using a generalized additive model-negative binomial regression. All estimates were adjusted or standardized by sex and age. RESULTS: Between 2008-2009 and 2020-2021, the adjusted admission to PRAC decreased (from 23.6/1000 people to 15.7/1000 people with an IRR = 0.97/year, 95% CI 0.97-0.98). The projected PRAC admission rate will decrease to 12.1/1000 (95%PI 10.8-13.3) by 2037-2038 and 9.0/1000 (95%PI 7.6-10.4) by 2051-2052. The projected volume of PRAC admission will be 73,988 (95%PI 65,960-81,425) at its highest point in 2037-2038 and 64,579 (95%PI 54,258-74,543) in 2051-2052. CONCLUSIONS AND IMPLICATIONS: The utilization of PRAC has decreased in the past decade, and a predicted decrease in PRAC use in future years is estimated. However, the volume of PRAC utilization will still increase for the next 15 years (until 2037-2038) due to our increasingly older population. These findings can inform service planning of PRAC access in Australia.

[The predictive value of microvascular obstruction for adverse left ventricular remodeling after primary percutaneous coronary intervention in patients with acute ST-elevation myocardial infarction: a prospective study].

Objectives: Microvascular obstruction (MVO) is a specific cardiac magnetic resonance (CMR) imaging feature in patients with acute myocardial infarction. The purpose of this study was to elucidate the predictive value of MVO in left ventricular adverse remodeling after primary percutaneous coronary intervention (PCI) in patients with acute ST-elevation myocardial infarction (STEMI). Methods: A total of 167 patients with STEMI undergoing primary PCI in the Chinese PLA General Hospital from 2016 to 2020 were enrolled in this prospective cohort study, the average age of study patients was 57±10 years old, with 151 males (90.4%) and 16 females (9.6%). The patients were divided into the MVO group (n=81) and non-MVO group (n=86) according to the presence or absence of MVO on CMR imaging, respectively. The primary endpoint of the study was the occurrence of left ventricular adverse remodeling, which was defined as an increase in left ventricular end diastolic volume (LVEDV) by >20% at 6 months after primary PCI compared with the baseline. Patients who completed follow-up were diagnosed as left ventricular adverse remodeling or no left ventricular adverse remodeling according to CMR. The baseline data, perioperative data, and related data of end points were compared between the MVO group and non-MVO group. Finally, the predictive value of MVO in left ventricular adverse remodeling was calculated by receiver operating characteristic curve analysis. Results: In the baseline data, preoperative thrombolysis in myocardial infarction (TIMI) flow (χ2=13.74, P=0.003) and postoperative TIMI flow (χ2=14.87, P=0.001) were both obviously decreased in the MVO group. After 6 months of follow-up, the incidence of left ventricular adverse remodeling in the MVO group was significantly higher than that in the non-MVO group [37.0%(27/73) vs. 18.9%(14/74), χ2=5.96, P=0.015]. The left ventricular end systolic volume at 6 months post infarction in the MVO group was significantly larger than that in the non-MVO group [(94±32) vs. (68±20) ml, t=-5.98, P<0.001], as well as the LVEDV [(169±38) vs. (143±29) ml, t=-4.74, P<0.001]. Receiver operating characteristic curve showed that the area under the curve of MVO size for predicting left ventricular adverse remodeling was 0.637. Conclusion: The risk of left ventricular adverse remodeling is significantly increased in patients with MVO after primary PCI for acute STEMI.

The effect of medical education and counselling on treatment adherence and disease severity in patients with acne vulgaris: a non-randomised interventional study.

INTRODUCTION: Acne vulgaris (AV) is a common inflammatory skin disease affecting adolescents and young adults. It affects one's self-esteem and social relationship. In addition, poor adherence to treatment can cause poor treatment response and disease recurrence. This study aims to determine the effectiveness of medical education and counselling on treatment adherence and disease severity. METHODS: This is a non-randomised interventional study with age- and treatment- matched control conducted in a tertiary dermatology clinic from July 2021 to June 2022. Patients in the intervention group received a 10 min video presentation on acne, followed by treatment counselling. The adherence rate was determined objectively (pill counting and tube weighing) and subjectively (ECOB questionnaire). The disease severity was assessed using the Comprehensive Acne Severity Scale (CASS) and Global Acne Grading System (GAGS). RESULTS: A total of 100 patients completed the 12-week study. With intervention, patients have better adherence to topical medication (5% benzoyl peroxide gel: 71% vs 57.9%, p= 0.031; 0.05% tretinoin cream: 58.7% vs 45.4%, p= 0.044) at week 12. However, the intervention program did not improve adherence to oral medication. Overall, with intervention, a significantly higher percentage of improvement in disease severity was noted (47.3% vs. 39.1%, p=0.044). Nonadherence to treatment was attributed mostly to forgetfulness in 54% of the patients, followed by a busy lifestyle (41%) and little knowledge of acne (26%). CONCLUSION: Patients have significantly better adherence to topical medication with education and counselling. Better adherence to treatment leads to more remarkable disease improvement.

Deciphering strontium sulfate precipitation via Ostwald's rule of stages: From prenucleation clusters to solution-mediated phase tranformation.

Multiple-step nucleation pathways have been observed during mineral formation in both inorganic and biomineral systems. These pathways can involve precursor aqueous species, amorphous intermediates, or metastable phases. Despite the widespread occurrence of these processes, elucidating the precise nucleation steps and the transformation mechanisms between each step remains a challenging task. Using a suite of potentiometric, microscopic, and spectroscopic tools, we studied the nucleation pathway of SrSO4 as a function of the physico-chemical solution parameters. Our observations reveal that below a threshold supersaturation, nucleation is driven by bound species, akin to the prenucleation cluster model, which directly leads to the formation of the stable phase celestine, SrSO4. At higher supersaturations, this situation is altered, with nucleation dominated by the consumption of free ions. Importantly, this change in nucleation mechanism is coupled to the formation of a hemihydrate metastable phase, SrSO4 · 1/2H2O, which eventually transforms into celestine, adhering to Ostwald's rule of stages. This transformation is a solution-mediated process, also occurring in the presence of a fluid film and is controlled by the physico-chemical parameters of the surrounding environment. It proceeds through the dissolution of the metastable phase and the de novo crystallization of the final phase. Overall, our results reveal that ion association taking place during the prenucleation stage dictates whether the nucleation pathway goes through an intermediate phase or not. This also underlines that although Ostwald's rule of stages is a common process, it is not a prerequisite for mineral formation-even in systems where it can occur.

[Research and development of an air sampling tube for chlorobenzene compounds and its supporting determination method].

Objective: To establish a GDH-3 air sample tube for simultaneous determination of twelve kinds of chlorobenzene compounds (CBs) in workplace air by gas chromatography. And to established a matching determination method. Methods: In October 2020, the vapor and aerosol CBs in workplace air were collected by GDH-3 air sampling tube, and desorption and elution with 3.00 ml toluene for 15 min, then the solution separated by DB-23 capillary column, and finally detected with microcell electron capture detector. Results: The quantitative determination ranges of twelve isomers of CBs were 0.71×10(-3)-2000.00 mg/L, with the correlative coefficients were 0.99967-0.99998. The minimum detectable concentrations were 0.04-112.63 µg/m(3), and the minimum quantification concentrations were 0.14-375.42 µg/m(3) (15.00 L sample, 3.00 ml sample solution) . The average elution efficiencies were 96.00%-104.00%. The within-run relative standard deviations (RSDs) were 2.54%-6.12%, and the between-run RSDs were 3.85%-7.87%. Sealed samples could be stable at room temperature for at least 15 days. Conclusion: GDH-3 air sample tube can be used for simultaneous determination of twelve kinds of CBs in workplace air by gas chromatography. The established supporting measurement method meets the measurement requirements of the occupational health standard detection method, and the it's suitable for the simultaneous determination of 12 kinds of CBS in the air.

[Application of a new solid adsorbent tube for the determination of three kinds of epoxy eompounds in air].

Objective: To develop a new solid sorbent tube for simultaneously capturing ethylene oxide (EO) , propylene oxide (PO) and epichlorohydrin (ECH) in air, and establish a complete set of method. Methods: In June 2018, EO, PO and ECH in air were captured by the new solid sorbent tube filled with carbon aerogel adsorbent, desorbed with solution of 5% (V/V) methanol-methylene chloride, separated through capillary chromatographic column, and then analyzed by gas chromatography-flame ionization detector. Results: The linear ranges of EO, PO and ECH were 0.24-960.00, 0.60-2384.00 and 0.12-472.40 mg/L respectively, and the related coefficients were between 0.99995-0.99997. The relative standard deviations (RSD) within the group were 1.66%-4.09%, 1.36%-4.43%, and 1.99%-5.65%, respectively, and the RSD between the group were 2.69%-4.95%, 2.77%-5.30%, and 3.27%-6.67%, respectively. The average desorption efficiencies were 88.25%-94.50%, 98.17%-98.60%, and 97.79%-101.04%, respectively. The samples could be stored at 4 ℃ refrigerator for at least 27 days. Conclusion: The newly developed solid sorbent tube filled with carbon aerogel adsorbent and its complete set of gas chromatography method could be used for sampling and quantitative detection of EO, PO and ECH in workplace air.

Down-regulation of long non-coding RNA DUXAP8 suppresses proliferation, metastasis and EMT by modulating miR-498 through TRIM44-mediated AKT/mTOR pathway in non-small-cell lung cancer.

OBJECTIVE: The long non-coding RNA double homeobox A pseudogene 8 (DUXAP8) was reported to be involved in the initiation and development of multiple cancers. However, the detailed biological role of DUXAP8 in non-small-cell lung cancer (NSCLC) remains unclear. Herein, we aimed to explore the biological function and molecular mechanism of DUXAP8 in NSCLC. PATIENTS AND METHODS: The levels of DUXAP8, microRNA-498 (miR-498) and tripartite motif-44 (TRIM44) were detected by Quantitative Real-time polymerase chain reaction (qRT-PCR). The cell proliferation, migration and invasion were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and transwell assays. Protein expression levels were detected by Western blot. The target relationships among DUXAP8, miR-498 and TRIM44 were predicted by starBase2.0 and confirmed using luciferase reporter and RNA pull-down assays. To detect the role of DUXAP8 in vivo, tumor xenografts were created. RESULTS: DUXAP8 and TRIM44 were upregulated in NSCLC tissues and cell lines, while miR-498 was downregulated. Functionally, knockdown of DUXAP8 could repress proliferation, migration, invasion, Epithelial-Mesenchymal Transition (EMT) and phosphorylation of AKT/mTOR in NSCLC cells. This inhibition could be restored by inhibiting miR-498 or overexpressing TRIM44. Furthermore, we also observed a positive correlation between DUXAP8 and TRIM44 expression, while the expressions of miR-498 and DUXAP8, as well as miR-498 and TRIM44, were negatively correlated in NSCLC tissues. Importantly, DUXAP8 could regulate the expression of TRIM44 via miR-498. Moreover, knockdown of DUXAP8 notably decreased the xenograft tumor volume, weight and number of metastatic nodules in vivo. CONCLUSIONS: Our results identified that LncRNA DUXAP8 could regulate cell proliferation, metastasis and EMT in NSCLC cells by inhibiting miR-498 through the activation of TRIM44-mediated AKT/mTOR pathway.

Associations of serum magnesium levels and calcium-magnesium ratios with mortality in patients with coronary artery disease.

AIMS: Low magnesium (Mg) and high calcium (Ca) levels are linked to increased cardiovascular disease (CVD) risk in the general population. This prospective study assessed whether there are any independent associations of serum Mg levels and Ca-Mg ratios with mortality in patients with coronary artery disease (CAD). METHODS: This prospective cohort study included 3380 CAD patients. Cox regression models were used to estimate associations of serum Mg and Ca-Mg ratio with risk of mortality. RESULTS: A total of 562 deaths (331 due to CVD) were recorded during a 7.59-year (median) follow-up. Spline plots displayed U-shaped associations between serum Mg levels and Ca-Mg ratios and risk of mortality. When compared with a moderate group, adjusted hazard ratios (95% confidence intervals) for low Mg levels and high Ca-Mg ratios were 1.59 (1.30-1.95) and 1.31 (1.06-1.61) for all-cause mortality, and 1.71 (1.32-2.22) and 1.44 (1.09-1.89) for CVD mortality, respectively. There was also a tendency to increase risk of mortality in patients with high serum Mg levels and low Ca-Mg ratios. Associations of low serum Mg and high Ca-Mg ratio with risk of mortality did not change when stratified by gender, body mass index, CAD type, estimated glomerular filtration rate, use of diuretics, or history of diabetes or hypertension. CONCLUSION: This study demonstrated that a moderate Ca-Mg ratio (range: 3.91-4.70) had the lowest mortality risk, and that low serum Mg and high Ca-Mg ratio were independent risk factors of mortality in CAD patients. Nevertheless, the optimal dose-response of Mg and Ca for mitigating CAD risk still requires further investigation.

Circulating retinol-binding protein 4 is associated with the development and regression of non-alcoholic fatty liver disease.

AIM: Retinol-binding protein 4 (RBP4), primarily secreted by liver and adipose tissue, has been linked with non-alcoholic fatty liver disease (NAFLD). However, investigations on the relationships between RBP4 and NAFLD have produced inconsistent results. Therefore, the association between serum RBP4 levels and the development or regression of NAFLD was prospectively investigated. METHODS: A total of 3389 Chinese adults, aged 40-75 years and followed-up for 3.09 years, were included and analyzed in the study. NAFLD was diagnosed by abdominal ultrasonography. Serum RBP4 levels were measured, and their relationship to NAFLD development and regression assessed. RESULTS: Of the 1318 participants without NAFLD at baseline, 410 developed NAFLD after follow-up. Baseline RBP4 was positively associated with incident NAFLD: the fully adjusted odds ratio (OR) was 2.01 with a 95% confidence interval (CI) of 1.33-3.04 (P = 0.003 for trend). After follow-up, a significant increase in RBP4 levels was observed in participants who developed NAFLD. On the other hand, in 1382 subjects diagnosed with NAFLD at baseline, 339 experienced NAFLD regression after follow-up. Thus, baseline RBP4 was inversely associated with NAFLD regression: the fully adjusted OR was 0.52 with a 95% CI of 0.34-0.80 (P < 0.001 for trend). A significant decrease in RBP4 after follow-up was also noted in participants with NAFLD regression. CONCLUSION: Serum RBP4 concentrations are associated with the development and regression of NAFLD, making them a potential novel preventative and therapeutic target in NAFLD management.

On Variation in Mindfulness Training: A Multimodal Study of Brief Open Monitoring Meditation on Error Monitoring.

A nascent line of research aimed at elucidating the neurocognitive mechanisms of mindfulness has consistently identified a relationship between mindfulness and error monitoring. However, the exact nature of this relationship is unclear, with studies reporting divergent outcomes. The current study sought to clarify the ambiguity by addressing issues related to construct heterogeneity and technical variation in mindfulness training. Specifically, we examined the effects of a brief open monitoring (OM) meditation on neural (error-related negativity (ERN) and error positivity (Pe)) and behavioral indices of error monitoring in one of the largest novice non-meditating samples to date (N = 212). Results revealed that the OM meditation enhanced Pe amplitude relative to active controls but did not modulate the ERN or behavioral performance. Moreover, exploratory analyses yielded no relationships between trait mindfulness and the ERN or Pe across either group. Broadly, our findings suggest that technical variation in scope and object of awareness during mindfulness training may differentially modulate the ERN and Pe. Conceptual and methodological implications pertaining to the operationalization of mindfulness and its training are discussed.

[Application of two risk assessment methods in ceramic manufacturing enterprises].

Objective: To explore the applicability of Singapore semi-quantitative assessment method and international committee on mining and metals occupational health risk assessment method in occupational health risk assessment of ceramic enterprises. Methods: From March 2017 to May 2018, A ceramic enterprise was selected for the investigation and testing of occupational health, and the risk assessment of the occupational-disease-inductive factors in the workplace was conducted by the semi-quantitative assessment method of Singapore and the occupational health risk assessment method of the international committee on mining and metals. Results: The occupational-disease-inductive factors in the production process of this ceramic enterprise mainly include silicon dust, noise, high temperature, carbon monoxide, carbon dioxide and so on. The two risk assessment methods were applied to assess the risk of occupational-disease-inductive factors in the workplace, and the results showed that the high risk level was 16.67%, the medium risk level was 63.33%, and the low risk level was 20.00%. The risk level of silicon dust is from low risk to high risk. Conclusion: The semi-quantitative assessment method and the occupational health risk assessment method of the International Commission on Mining and Metals are simple to operate and practical, and are suitable for the assessment of occupational hazards in ceramic enterprises.

[Simultaneous determination of four kinds methyl acrylate compounds in workplace air].

Objective: To develop a solvent desorption-gas chromatography method for simultaneous determination of methyl methacrylate (MMA) , ethyl methacrylate (EMA) , n-propyl methacrylate (PMA) and butyl methacrylate (BMA) in workplace air. Methods: MMA, EMA, PMA and BMA in workplace air were captured by charcoal tubes and desorbed with carbon disulfide, separated through capillary chromatographic column, and then analyzed by gas chromatography-flame ionization detector. Results: The linear ranges of MMA, EMA, PMA and BMA were 0-8 305.00 mg/L, 0-9 080.50 mg/L, 0-8 899.00 mg/L and 0-8 371.00 mg/L respectively, and the related coefficients were between 0.999 96-0.999 98. The relative standard deviations (RSD) within the group were 0.56%-1.71%, 0.45%-1.65%, 0.51%-1.49% and 0.45%-1.50% respectively, and the RSD between the group were 1.14%-2.79%, 0.79%-2.13%, 0.93%-2.30% and 1.09%-2.84% respectively. The average desorption efficiencies were 95.76%-99.58%, 97.82%-102.28%, 98.55%-102.28%and 98.70%-102.40% respectively. The minimum quantification concentrations were 0.12 mg/m(3), 0.10 mg/m(3), 0.07 mg/m(3) and 0.07 mg/m(3) respectively (3.00 L sample) . The samples could be stored at room temperature for at least 7 days. Conclusion: This method could be used for monitoring of MMA, EMA, PMA and BMA in workplace air.

Study on ceramide modulates EAAT-2 participation in the immunoinflammatory response in schizophrenia.

OBJECTIVE: Abnormal immunoinflammatory responses play important roles in the pathogenesis of schizophrenia, but the underlying molecular mechanisms are still unclear. MATERIALS AND METHODS: In this study, the ceramide agonist daunorubicin (DNR) was injected into the lateral ventricles to induce ceramide accumulation. The behavioral tests were used to observe schizophrenia-like behavioral changes. Changes in the mRNA levels of the proinflammatory cytokines and the protein levels of the glutamate transporter excitatory amino acid transporter-2 (EAAT-2) were detected. After inhibition of nuclear factor-κB (NF-κB), the above indices were detected again. Nissl staining was used to assess neuronal damage. RESULTS: After intracerebroventricular injection of DNR, ceramide significantly accumulated in the hippocampus, and behavioral tests revealed negative schizophrenia symptoms accompanied by induced learning and memory dysfunction. Furthermore, the hippocampus demonstrated increased mRNA levels of the proinflammatory cytokines including interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α (TNF-α) and significantly decreased EAAT-2 protein levels. Nissl staining revealed neuronal damage after ceramide accumulation. The NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) reduced the behavioral abnormalities caused by ceramide accumulation, downregulated CONCLUSIONS: The experimental results suggest that ceramide reduces EAAT-2 expression through the NF-κB/TNF-α pathway and causes neuronal excitotoxicity in the pathogenesis of schizophrenia, leading to neuronal damage.

[Study on determination of ethylal in workplace air by gas chromatography].

Objective: A solvent desorption-gas chromatography method for determination of ethylal in workplace air has been established. Methods: Ethylal in workplace air was collected by activated carbon tube and desorbed with carbon disulfide, and the desorption solutions were analysed by capillary column GC with FID detector. Results: The method presented a good linearity in the range of 0.87~34 800.00 mg/L of ethylal in the standard solution, with the correlation coefficient being r=0.999 7. The limit of detection and the limit of quantification of this method were respectively 0.20 mg/L and 0.80 mg/L, and the minimum detectable concentration and the minimum quantification concentration of this method were respectively 0.17 mg/m(3) and 0.60 mg/m(3) per 1.50 L of air.The within-run precision of the method was 2.93%-6.20%, and the between-run precision 3.67%-6.44%. The desorption efficiency between 94.22%-97.27%. Ethylal in activated carbon tube could be kept at least 7 days at room temperature without significant loss. Conclusion: The method could be used for determination of ethylal in workplace air.

Dynamic self-assembly of DNA minor groove-binding ligand DB921 into nanotubes triggered by an alkali halide.

We describe a novel self-assembling supramolecular nanotube system formed by a heterocyclic cationic molecule which was originally designed for its potential as an antiparasitic and DNA sequence recognition agent. Our structural characterisation work indicates that the nanotubes form via a hierarchical assembly mechanism that can be triggered and tuned by well-defined concentrations of simple alkali halide salts in water. The nanotubes assembled in NaCl have inner and outer diameters of ca. 22 nm and 26 nm respectively, with lengths that reach into several microns. Our results suggest the tubes consist of DB921 molecules stacked along the direction of the nanotube long axis. The tubes are stabilised by face-to-face π-π stacking and ionic interactions between the charged amidinium groups of the ligand and the negative halide ions. The assembly process of the nanotubes was followed using small-angle X-ray and neutron scattering, transmission electron microscopy and ultraviolet/visible spectroscopy. Our data demonstrate that assembly occurs through the formation of intermediate ribbon-like structures that in turn form helices that tighten and compact to form the final stable filament. This assembly process was tested using different alkali-metal salts, showing a strong preference for chloride or bromide anions and with little dependency on the type of cation. Our data further demonstrates the existence of a critical anion concentration above which the rate of self-assembly is greatly enhanced.