We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
This research aimed to assess the agronomic performance of the progeny (F3 and F4 generations) of 48 newly developed Aus rice lines, using a randomized-complete-block-design under rainfed conditions. We found a wide range of variations in yield and yield-contributing traits among the studied genotypes. High board sense heritability percentages were found for sterility percentage (99.50 and 97.20), thousand-grain-weight (88.10 and 90.20 g), plant-height (84.90 and 86.90 cm) and day-to-maturity (84.50 and 97.60 d) in both F3 and F4 generations, respectively. However, the highest genetic advance as mean percentage was observed for sterility (48.00 and 50.60), effective tillers number per hill (ET) (44.70 and 47.10), total tillers number per hill (TT) (43.00 and 45.40) and filled-grains per panicle (41.00 and 43.20) respectively. Notably, the correlation study also identified the traits, TT (r = 0.31 and 0.45), ET (r = 0.30 and 0.44), straw yield (r = 0.57 and 0.39) and harvest index (r = 0.63 and 0.67) as effective for improving grain yield in both F3 and F4 generations, respectively. We identified higher grain yield per hill (g) and shorter to moderate crop growth duration (days) in several distinct accessions, including R1-49-7-1-1, R3-26-4-3-1, R1-6-2-3-1, R1-13-1-1-1, R1-50-1-1-1, R3-49-4-3-1, R1-47-7-3-1, R2-26-6-2-2, R3-30-1-2-1 and R1-44-1-2-1, among the 48 genotypes in both the F3 and F4 generations. A further location-specific agronomic study is recommended to assess the drought tolerance of these promising genotypes. This will further assess their suitability as potential breeding materials when developing rice varieties adapted to grow under fluctuating rainfalls conditions.
Military Servicemembers and Veterans are at elevated risk for suicide, but rarely self-identify to their leaders or clinicians regarding their experience of suicidal thoughts. We developed an algorithm to identify posts containing suicide-related content on a military-specific social media platform.
Methods
Publicly-shared social media posts (n = 8449) from a military-specific social media platform were reviewed and labeled by our team for the presence/absence of suicidal thoughts and behaviors and used to train several machine learning models to identify such posts.
Results
The best performing model was a deep learning (RoBERTa) model that incorporated post text and metadata and detected the presence of suicidal posts with relatively high sensitivity (0.85), specificity (0.96), precision (0.64), F1 score (0.73), and an area under the precision-recall curve of 0.84. Compared to non-suicidal posts, suicidal posts were more likely to contain explicit mentions of suicide, descriptions of risk factors (e.g. depression, PTSD) and help-seeking, and first-person singular pronouns.
Conclusions
Our results demonstrate the feasibility and potential promise of using social media posts to identify at-risk Servicemembers and Veterans. Future work will use this approach to deliver targeted interventions to social media users at risk for suicide.
Mild decline in independent functioning is a core diagnostic criterion for Mild Cognitive Impairment. Performance-based assessments have been considered the gold standard to identify subtle deficits in functioning. Existing assessments were largely designed using demographically homogenous samples (white, highly educated, middle class) and often assume tasks are performed similarly across populations. The current study aimed to validate the utility of the Performance Assessment of Self-Care Skills (PASS) in determining cognitive status in a sample of predominantly African American, low-income older adults.
Participants and Methods:
Cognition and functional capacity were measured in n=245 older participants (aged 50+ years) who were recruited from a larger community study located in Pittsburgh, PA. Cognitive status was defined by a mean split on the Modified Mini Mental Status Examination (3MS) score (84/100). Participants above the cutoff were classified as unlikely cognitive impairment (UCI) and those below classified as potential cognitive impairment (PCI). Functional capacity was assessed using the number of cues provided on three PASS subtasks: shopping, medication management, and critical information retrieval (higher score = worse functioning). Self-reported cognitive and functional decline was assessed via the Everyday Cognition (ECog) questionnaire (higher score = greater decline). Generalized linear models compared performance scores between groups adjusting for literacy (WRAT3), age, and education. Receiver operating characteristic curve (ROC) analyses were run for select functional performance scores to assess their predictive ability in discriminating between PCI and UCI.
Results:
Compared to the UCI group (N = 179), the PCI group (N = 66) was older (68 vs. 65 years, p = 0.05), less educated (11 years vs. 12 years, p < 0.01), had lower WRAT3 z-scores (0.19 vs. -0.55, p < .01), and required more cues on the shopping (4.33 vs. 8.54, p < 0.01) and medication management PASS subtasks (2.74 vs. 6.56, p < .01). Both groups reported elevated levels of subjective cognitive complaints on the ECog (1.46 vs. 1.56, p = .09) and performed similarly on the critical information retrieval PASS subtask (0.25 vs 0.54, p = .06). When discerning between UCI and PCI groups, the PASS Shopping subtask had an optimal cut-off score of 4, sensitivity of 0.86, specificity of 0.47, positive predictive value (PPV) of 0.37, and area under the curve (AUC) of 0.71. PASS Medication Management had an optimal cut-off score of 3, sensitivity of 0.77, specificity of 0.56, PPV of 0.39, and AUC of 0.74.
Conclusions:
Subjective functional decline and performance on the critical information retrieval subtask were not associated with cognitive groups. PASS shopping and medication management had moderately high AUCs, suggesting they can reliably distinguish between groups. However, both tasks also exhibited low PPVs, low levels of specificity, and high levels of sensitivity, making them strong “rule-out” tests but poor “rule-in” tests in this sample. Because accurate assessment of functioning is useful for MCI and critical to dementia diagnosis, it is imperative we understand how these tasks function across different populations. Future work should 1) validate measures of functional ability across different populations and 2) develop population-appropriate assessments for use in clinical and research settings.
Patients with unbalanced common atrioventricular canal can be difficult to manage. Surgical planning often depends on pre-operative echocardiographic measurements. We aimed to determine the added utility of cardiac MRI in predicting successful biventricular repair in common atrioventricular canal.
Methods:
We conducted a retrospective cohort study of children with common atrioventricular canal who underwent MRI prior to repair. Associations between MRI and echocardiographic measures and surgical outcome were tested using logistic regression, and models were compared using area under the receiver operator characteristic curve.
Results:
We included 28 patients (median age at MRI: 5.2 months). The optimal MRI model included the novel end-diastolic volume index (using the ratio of left ventricular end-diastolic volume to total end-diastolic volume) and the left ventricle–right ventricle angle in diastole (area under the curve 0.83, p = 0.041). End-diastolic volume index ≤ 0.18 and left ventricle–right ventricle angle in diastole ≤ 72° yield a sensitivity of 83% and specificity of 81% for successful biventricular repair. The optimal multimodality model included the end-diastolic volume index and the echocardiographic atrioventricular valve index with an area under the curve of 0.87 (p = 0.026).
Conclusions:
Cardiac MRI can successfully predict successful biventricular repair in patients with unbalanced common atrioventricular canal utilising the end-diastolic volume index alone or in combination with the MRI left ventricle–right ventricle angle in diastole or the echocardiographic atrioventricular valve index. A prospective cardiac MRI study is warranted to better define the multimodality characteristic predictive of successful biventricular surgery.
A design of a sub-scale Boundary Layer Ingestion (BLI) fan for a transonic test rig is presented. The fan is intended to be used in flow conditions with varying distortion patterns representative of a BLI application on an aircraft. The sub-scale fan design is based on a design study of a full-scale fan for a BLI demonstration project for a Fokker 100 aircraft. CFD results from the full-scale fan design and the ingested distortion pattern from CFD analyses of the whole aircraft are used as inputs for this study. The sub-scale fan is designed to have similar performance characteristics to the full-scale fan within the capabilities of the test facility. The available geometric rig envelope in the test facility necessitates a reduction in geometric scale and consideration of the operating conditions. Fan blades and vanes are re-designed for these conditions in order to mitigate the effects of the scaling. The effects of reduced size, increased relative tip clearance and thicknesses of the blades and vanes are evaluated as part of the step-by-step adaption of the design to the sub-scale conditions. Finally, the installation effects in the rig are simulated including important effects of the by-pass flow on the running characteristics and the need to control the effective fan nozzle area in order to cover the available fan operating range. The predicted operating behaviour of the fan as installed in the coming transonic test rig gives strong indication that the sub-scale fan tests will be successful.
Drains are used post-parotidectomy to reduce seroma and haematoma formation. Tissue-derived thrombin sealant can enable a drainless procedure, allowing for an earlier discharge, less discomfort and a more cost-efficient method. This study aimed to assess whether tissue sealant improves wound-related outcomes in parotidectomy.
Method
A systematic literature review was performed using a standardised published methodology and custom database search strategy. A fixed-effect meta-analysis of the combined complications was conducted.
Results
Thirteen studies were identified relating to parotidectomy procedures using tissue sealants, of which nine were included in the quantitative synthesis. Our analysis suggested a reduction in the complication rates, including haematoma and seroma, with drainless parotidectomy procedures involving tissue sealant use when compared with conventional procedures with post-operative drain use.
Conclusion
Fibrin sealant in parotidectomy may be used to facilitate a drainless approach, expediting recovery and offering better comfort to patients.
Surgery is the recommended treatment for resectable T4a laryngeal and hypopharyngeal carcinoma. Non-surgical treatment is an option in a select few patients.
Method
This retrospective study was undertaken to assess the treatment outcomes in patients with resectable T4a carcinoma of the larynx and hypopharynx who received either surgical or non-surgical treatment at our institute and to assess factors influencing these outcomes.
Results
A total of 120 patients were included in the study. They were divided into groups A, B and C based on the presence of extralaryngeal spread through laryngeal membrane, cartilage or both. The overall survival was better among patients who received surgery than those who received non-surgical treatment in the three groups. The factor influencing overall survival was the treatment given in the form of surgical versus non-surgical treatment.
Conclusion
Surgery is the preferred treatment for T4a laryngeal and hypopharyngeal carcinoma, even in patients with extralaryngeal spread without cartilage erosion.
ABSTRACT IMPACT: Patients living in overcrowded zip codes were at increased risk of contracting severe COVID-19 after controlling for confounding disease and socioeconomic factors OBJECTIVES/GOALS: This study sought to examine whether residences in over-crowded zip codes with higher reported over-crowding represented an independent risk factor for severe COVID-19 infection, defined by presentation to an emergency department. METHODS/STUDY POPULATION: In this zip code tabulated area (ZCTA)-level analysis, we used NYC Department of Health disease surveillance data in March 2020 merged with data from the CDC and ACS to model suspected COVID-19 case rates by zip code over-crowdedness (households with greater than 1 occupant per room, in quartiles). We defined suspected COVID-19 cases as emergency department reported cases of pneumonia and influenza-like illness. Our final model employed a multivariate Poisson regression models with controls for known COVID-19 clinical (prevalence of obesity, coronary artery disease, and smoking) and related socioeconomic risk factors (percentage below federal poverty line, median income by zip-code, percentage White, and proportion of multigenerational households) after accounting for multicollinearity. RESULTS/ANTICIPATED RESULTS: Our analysis examined 39,923 suspected COVID-19 cases across 173 ZCTAs in NYC between March 1 and March 30 2020. We found that, after adjusted analysis, for every quartile increase in defined over-crowdedness, case rates increased by 32.8% (95% CI: 22.7%% to 34.0%, P < 0.001). DISCUSSION/SIGNIFICANCE OF FINDINGS: Over-crowdedness by zip code may be an independent risk factor for severe COVID-19. Social distancing measures such as school closures that increase house-bound populations may inadvertently worsen the risk of COVID-19 contraction in this setting.
The catostylid jellyfish, Crambionella annandalei was originally described by Rao (1932) based on a preserved specimen collected from the Andaman Sea. Since then, no detailed taxonomic studies have been conducted and the species is often misidentified. Here, we provide a detailed morphological re-description of C. annandalei from fresh material collected at a variety of locations along the east coast of India. The species can be distinguished from its congeners by a combination of morphological characters, the most important of which are the proportion of terminal club length to oral arm length (0.48 ± 0.031), the proportion of the distal portion of the oral arm to naked proximal portion (7.25 ± 0.268) and the body colour. The occurrence of intra-specific colour variation in fresh specimens was also observed in the present study.
To determine if a global mid-upper arm circumference (MUAC) cut-off can be established to classify underweight in adults (men and non-pregnant women).
Design:
We conducted an individual participant data meta-analysis (IPDMA) to explore the sensitivity (SENS) and specificity (SPEC) of various MUAC cut-offs for identifying underweight among adults (defined as BMI < 18·5 kg/m2). Measures of diagnostic accuracy were determined every 0·5 cm across MUAC values from 19·0 to 26·5 cm. A bivariate random effects model was used to jointly estimate SENS and SPEC while accounting for heterogeneity between studies. Various subgroup analyses were performed.
Setting:
Twenty datasets from Africa, South Asia, Southeast Asia, North America and South America were included.
Participants:
All eligible participants from the original datasets were included.
Results:
The total sample size was 13 835. Mean age was 32·6 years and 65 % of participants were female. Mean MUAC was 25·7 cm, and 28 % of all participants had low BMI (<18·5 kg/m2). The area under the receiver operating characteristic curve for the pooled dataset was 0·91 (range across studies 0·61–0·98). Results showed that MUAC cut-offs in the range of ≤23·5 to ≤25·0 cm could serve as an appropriate screening indicator for underweight.
Conclusions:
MUAC is highly discriminatory in its ability to distinguish adults with BMI above and below 18·5 kg/m2. This IPDMA is the first step towards determining a global MUAC cut-off for adults. Validation studies are needed to determine whether the proposed MUAC cut-off of 24 cm is associated with poor functional outcomes.
Less is known about the relationship between conduct disorder (CD), callous–unemotional (CU) traits, and positive and negative parenting in youth compared to early childhood. We combined traditional univariate analyses with a novel machine learning classifier (Angle-based Generalized Matrix Learning Vector Quantization) to classify youth (N = 756; 9–18 years) into typically developing (TD) or CD groups with or without elevated CU traits (CD/HCU, CD/LCU, respectively) using youth- and parent-reports of parenting behavior. At the group level, both CD/HCU and CD/LCU were associated with high negative and low positive parenting relative to TD. However, only positive parenting differed between the CD/HCU and CD/LCU groups. In classification analyses, performance was best when distinguishing CD/HCU from TD groups and poorest when distinguishing CD/HCU from CD/LCU groups. Positive and negative parenting were both relevant when distinguishing CD/HCU from TD, negative parenting was most relevant when distinguishing between CD/LCU and TD, and positive parenting was most relevant when distinguishing CD/HCU from CD/LCU groups. These findings suggest that while positive parenting distinguishes between CD/HCU and CD/LCU, negative parenting is associated with both CD subtypes. These results highlight the importance of considering multiple parenting behaviors in CD with varying levels of CU traits in late childhood/adolescence.
Background: Since January 1, 2016 2358 people have died from opioid poisoning in Alberta. Buprenorphine/naloxone (bup/nal) is the recommended first line treatment for opioid use disorder (OUD) and this treatment can be initiated in emergency departments and urgent care centres (EDs). Aim Statement: This project aims to spread a quality improvement intervention to all 107 adult EDs in Alberta by March 31, 2020. The intervention supports clinicians to initiate bup/nal for eligible individuals and provide rapid referrals to OUD treatment clinics. Measures & Design: Local ED teams were identified (administrators, clinical nurse educators, physicians and, where available, pharmacists and social workers). Local teams were supported by a provincial project team (project manager, consultant, and five physician leads) through a multi-faceted implementation process using provincial order sets, clinician education products, and patient-facing information. We used administrative ED and pharmacy data to track the number of visits where bup/nal was given in ED, and whether discharged patients continued to fill any opioid agonist treatment (OAT) prescription 30 days after their index ED visit. OUD clinics reported the number of referrals received from EDs and the number attending their first appointment. Patient safety event reports were tracked to identify any unintended negative impacts. Evaluation/Results: We report data from May 15, 2018 (program start) to September 31, 2019. Forty-nine EDs (46% of 107) implemented the program and 22 (45% of 49) reported evaluation data. There were 5385 opioid-related visits to reporting ED sites after program adoption. Bup/nal was given during 832 ED visits (663 unique patients): 7 visits in the 1st quarter the program operated, 55 in the 2nd, 74 in the 3rd, 143 in the 4th, 294 in the 5th, and 255 in the 6th. Among 505 unique discharged patients with 30 day follow up data available 319 (63%) continued to fill any OAT prescription after receiving bup/nal in ED. 16 (70%) of 23 community clinics provided data. EDs referred patients to these clinics 440 times, and 236 referrals (54%) attended their first follow-up appointment. Available data may under-report program impact. 5 patient safety events have been reported, with no harm or minimal harm to the patient. Discussion/Impact: Results demonstrate effective spread and uptake of a standardized provincial ED based early medical intervention program for patients who live with OUD.
Terminal heat stress leads to sizeable yield loss in late-sown wheat in tropical environments. Several synthetic compounds are known to counteract plant stress emanating from abiotic factors. A field experiment was conducted in Sabour (eastern India) during 2013–2016 to investigate the field efficacy of two synthetic compounds, calcium chloride (CaCl2) and arginine, for improving grain yield of two contrasting wheat cultivars (DBW 14 and K 307) facing terminal heat stress. For this, foliar spray of 18.0 mM CaCl2 at booting (CCB) or anthesis (CCA), 9.0 mM CaCl2 at both booting and anthesis (CCB+A), 2.5 mM arginine at booting (ARGB) or anthesis (ARGA) and 1.25 mM arginine at both booting and anthesis (ARGB+A) treatments along with no-spray and water-spray treatments were evaluated in late-sown wheat. The highest grain yield was recorded in treatment CCB+A, followed by CCA and ARGB+A. However, the effect of these compounds was marginal on grain yield when applied only at the booting stage. Grains/ear and thousand-grain weight were found to be the critical determinants for yield in late-sown wheat. During the anthesis to grain filling period, flag-leaf chlorophyll degradation and increase in relative permeability in no-spray treatment were 34–36% and 29–52%, respectively, but these values were reduced considerably in CCB+A treatment followed CCA. Thus, foliar spray of 9.0 mM CaCl2 both at booting and anthesis stages may be recommended for alleviating the negative impacts of terminal heat stress in late-sown wheat and improving its productivity (>13%).
This chapter reviews the systematics of partial melting of mantle lithologies – like peridotite and eclogite – in the presence of carbon dioxide. It discusses the composition of mantle-derived magmas generated in the presence of carbon dioxide and whether magmas erupted on Earth’s surface resemble carbonated magmas from the mantle. It reviews how the production of carbon dioxide-rich magma in the mantle varies as a function of tectonic settings – beneath continents and oceans and in subduction zones – and time.
To identify opportunities and challenges for the promotion of healthy, sustainable oil consumption in India.
Design:
We use a framework for policy space analysis which distinguishes between policy context, process and characteristics.
Setting:
We focus on the Indian edible oils sector and on factors shaping the policy space at a national level.
Participants:
The study is based on the analysis of policy documents and semi-structured interviews with key experts and stakeholders in the edible oils sector.
Results:
We find opportunities associated with the emergence of multisectoral policy frameworks for climate adaptation and non-communicable disease (NCD) prevention at a national level which explicitly include the oils sector, the existence of structures for sectoral policy coordination, some supportive factors for the translation of nutrition evidence into practice, and the possibility of integrating nutrition-sensitive approaches within current state-led agricultural interventions. However, the trade-offs perceived across sustainability, NCD prevention and food security objectives in the vegetable oils sector are considered a barrier for policy influence and implementation. Sustainability and nutrition advocates tend to focus on different segments of the value chain, missing potential synergies. Moreover, policy priorities are dominated by historical concerns for food security, understood as energy provision, as well as economic and strategic priorities.
Conclusions:
Systematic efforts towards identifying synergistic approaches, from agricultural production to distribution of edible oils, as well as increased involvement of nutrition advocates with upstream policies in the oils sector, could increase policy influence for advocates of both nutrition and sustainability.
Lomatogonium gaurgopalii sp. nov., a new species of Gentianaceae from Sikkim Himalaya, is described and illustrated. It can be distinguished from its morphologically closest relative, Lomatogonium cherukurianum S.K.Dey & D.Maity, mainly by its robust habit, longer internodes, much larger creamy yellow flower and much larger floral parts; the presence of many hairs in an inverted semilunar arrangement behind the filament bases; and its larger, narrowly ovoid to narrowly ellipsoid ovary. Lomatogonium gaurgopalii is also unique in having pollen grains with striate-reticulate exine ornamentation without perforations.
Hydrilla is an invasive aquatic plant that has rapidly spread through many inland water bodies across the globe by outcompeting native aquatic plants. The negative impacts of hydrilla invasion have become a concern for water resource management authorities, power companies, and environmental scientists. The early detection of hydrilla infestation is very important to reduce the costs associated with control and removal efforts of this invasive species. Therefore, in this study, we aimed to develop a tool for rapid, frequent, and large-scale monitoring and predicting spatial extent of hydrilla habitat. This was achieved by integrating in situ and Landsat 8 Operational Land Imager satellite data for Lake J. Strom Thurmond, the largest US Army Corps of Engineers lake east of the Mississippi River, located on the border of Georgia and South Carolina border. The predictive model for presence of hydrilla incorporated radiometric and physical measurements, including remote-sensing reflectance, Secchi disk depth (SDD), light-attenuation coefficient (Kd), maximum depth of colonization (Zc), and percentage of light available through the water column (PLW). The model-predicted ideal habitat for hydrilla featured high SDD, Zc, and PLW values, low values of Kd. Monthly analyses based on satellite images showed that hydrilla starts growing in April, reaches peak coverage around October, begins retreating in the following months, and disappears in February. Analysis of physical and meteorological factors (i.e., water temperature, surface runoff, net inflow, precipitation) revealed that these parameters are closely associated with hydrilla extent. Management agencies can use these results not only to plan removal efforts but also to evaluate and adapt their current mitigation efforts.
Background: Buprenorphine/naloxone (bup/nal) is a partial opioid agonist/antagonist and recommended first line treatment for opioid use disorder (OUD). Emergency departments (EDs) are a key point of contact with the healthcare system for patients living with OUD. Aim Statement: We implemented a multi-disciplinary quality improvement project to screen patients for OUD, initiate bup/nal for eligible individuals, and provide rapid next business day walk-in referrals to addiction clinics in the community. Measures & Design: From May to September 2018, our team worked with three ED sites and three addiction clinics to pilot the program. Implementation involved alignment with regulatory requirements, physician education, coordination with pharmacy to ensure in-ED medication access, and nurse education. The project is supported by a full-time project manager, data analyst, operations leaders, physician champions, provincial pharmacy, and the Emergency Strategic Clinical Network leadership team. For our pilot, our evaluation objective was to determine the degree to which our initiation and referral pathway was being utilized. We used administrative data to track the number of patients given bup/nal in ED, their demographics and whether they continued to fill bup/nal prescriptions 30 days after their ED visit. Addiction clinics reported both the number of patients referred to them and the number of patients attending their referral. Evaluation/Results: Administrative data shows 568 opioid-related visits to ED pilot sites during the pilot phase. Bup/nal was given to 60 unique patients in the ED during 66 unique visits. There were 32 (53%) male patients and 28 (47%) female patients. Median patient age was 34 (range: 21 to 79). ED visits where bup/nal was given had a median length of stay of 6 hours 57 minutes (IQR: 6 hours 20 minutes) and Canadian Triage Acuity Scores as follows: Level 1 – 1 (2%), Level 2 – 21 (32%), Level 3 – 32 (48%), Level 4 – 11 (17%), Level 5 – 1 (2%). 51 (77%) of these visits led to discharge. 24 (47%) discharged patients given bup/nal in ED continued to fill bup/nal prescriptions 30 days after their index ED visit. EDs also referred 37 patients with OUD to the 3 community clinics, and 16 of those individuals (43%) attended their first follow-up appointment. Discussion/Impact: Our pilot project demonstrates that with dedicated resources and broad institutional support, ED patients with OUD can be appropriately initiated on bup/nal and referred to community care.
Dust vortices with a void at the centre are reported in this paper. The role of the spatial variation of the plasma potential in the rotation of dust particles is studied in a parallel plate glow discharge plasma. Probe measurements reveal the existence of a local potential minimum in the region of formation of the dust vortex. The minimum in the potential well attracts positively charged ions, while it repels the negatively charged dust particles. Dust rotation is caused by the interplay of the two oppositely directed ion drag and Coulomb forces. The balance between these two forces is found to play a major role in the radial confinement of the dust particles above the cathode surface. Evolution of the dust vortex is studied by increasing the discharge current from 15 to 20 mA. The local minimum of the potential profile is found to coincide with the location of the dust vortex for both values of discharge currents. Additionally, it is found that the size of the dust vortex as well as the void at the centre increases with the discharge current.