The minimum rank of universal adjacency matrices

In this paper we introduce a new parameter for a graph called the {\it minimum universal rank}. This parameter is similar to the minimum rank of a graph. For a graph $G$ the minimum universal rank of $G$ is the minimum rank over all matrices of the form $$U(\alpha, \beta, \gamma, \delta) = \alpha A + \beta I + \gamma J + \delta D$$ where $A$ is the adjacency matrix of $G$, $J$ is the all ones matrix and $D$ is the matrix with the degrees of the vertices in the main diagonal, and $\alpha\neq 0, \beta, \gamma, \delta$ are scalars. Bounds for general graphs based on known graph parameters are given, as is a formula for the minimum universal rank for regular graphs based on the multiplicity of the eigenvalues of $A$. The exact value of the minimum universal rank of some families of graphs are determined, including complete graphs, complete bipartite graph, paths and cycles. Bounds on the minimum universal rank of a graph obtained by deleting a single vertex are established. It is shown that the minimum universal rank is not monotone on induced subgraphs, but bounds based on certain induced subgraphs, including bounds on the union of two graphs, are given. Finally we characterize all graphs with minimum universal rank equal to 0 and to 1

Comparison of Hydrological and Meteorological Drought Monitoring using RDI and EDI Indices

Drought is a natural event that causes water deficit in many countries every year. Arid and semi-arid climate and inappropriate distribution of rain in terms of spatially and temporally has caused doubled increase of negative effects of water deficit in Iran. It is necessary to study drought phenomenon in order to plan and manage encountering with this phenomenon. In this research, the meteorological and hydrological drought situation of Doroud-Boroujerd basin was investigated using data from five meteorological stations and three hydrometric stations from 1987 to 2016. For this purpose, EDI drought meteorological index and RDI drought hydrological index with threshold discharges of Q70 and Q90 were used. The daily precipitation data were used to calculate EDI index and daily discharge data were used to determine RDI index. The results were assessed and compared on annual, monthly and regional scale. The results indicated the prevalence of normal and moderate droughts in most areas of the basin. Moreover, it was found that the EDI index is less sensitive to the length of the statistical period and has logical time changes; hence, it has the capability required for use in drought monitoring system. This index determined 2012 as the driest year. In addition, RDI index showed 1991 as the driest year in both discharge cases, Q70 and Q90 threshold

Sense of Coherence or resilience as predictors of psychological distress in nursing students during the COVID-19 pandemic

BackgroundThe COVID-19 pandemic lead to the occurrence of numerous psychological distress among students. This study aimed to determine the level of psychological distress as well as the predictive role of Sense of Coherence (SOC) and resilience in nursing students.MethodsA cross-sectional descriptive study was conducted on 310 nursing students in Ahvaz Jundishapur University of Medical Sciences, Iran. The data of the study was collected through the demographic information questionnaire, the General Health Questionnaire (GHQ), the Academic Resilience Inventory (ARI), and the Sense of Coherence Scale (SOC-13).ResultsStudents' mean scores for the GHQ, ARI, and SOC were 5.81 ± 1.37, 102.88 ± 11.91, and 54.54 ± 6.46, respectively. Regression models showed that two domains of SOC [meaningfulness (β = −0.28, p < 0.001), manageability (β = −0.19, p = 0.001)], female gender (β = 0.12, p = 0.015), and overall ARI (β = −0.12, p = 0.037), were significantly associated with the GH of nursing students. SOC domains [meaningfulness (β = −0.19, p = 0.002), manageability (β = −0.15, p = 0.006)], problem-oriented/positive thinking domain of ARI (β = −0.15, p = 0.011), sex (β = 0.12, p = 0.015), and history of death in first-degree relatives (β = 0.12, p = 0.021) were significantly associated with social dysfunction domain of GH. Three domains of SOC [meaningfulness (β = −0.26, p < 0.001), manageability (β = −0.13, p = 0.032), and comprehensibility (β = −0.13, p = 0.039)], were significantly associated with psychological distress domain of GH.ConclusionOur results indicated that low SOC and resilience were predictors of psychological distress in nursing students. Accordingly, interventions such as teaching stress management skills, the skills of using positive coping methods in dealing with stressful situations, and self-management skills are necessary to improve the level of resilience and SOC in nursing students

Prospective evaluation of acute radiation – induced skin reactions in patients after head and neck radiotherapy

     Acute Radiation- induced Skin reaction (ARISR) is a common side effect in the majority of patients receiving radiotherapy. ARISR is often characterized by swelling, redness, pigmentation, dry and moist desquamation, edema, ulceration, bleeding and necrosis of the Skin. This study was carried out to evaluate prevalence and severity of ARISR in patients with head and neck cancer undergoing radiotherapy and determining skin dose–response relationship. From December 2014 to September 2015, we evaluated 88 patients with head and neck cancer. The acute skin toxicity was scored based on RTOG toxicity criteria. Analysis of data using statistical software SPSS (version20) and ANOVA or chi- square test was done, with P  0.05 considered as significant. 98.86% of patients experienced dermatitis, but were mild in most cases.There was no significant differences in age, sex, stage, and field size between patients with dermatitis

Pancytopenia as a rare complication of acute Brucellosis: A case report

Human Brucellosis still challenges many physicians, especially in developing countries where it is still a very common, but sometimes ignored disease. Its reemergence in developed countries and its status as a class B bioterrorist agent has recently attracted much interest. Having over 500,000 new cases annually, Brucellosis is known as one of the most common zoonotic infections in the world and “the great imitator” because of many clinical and hematological manifestations. Brucellosis is still endemic in many developing countries and remains under-diagnosed and sometimes missed reported. Although this province (Kurdistan, Iran) is a Brucella endemic area with a very high prevalence and incidence rate, except for very few and negligible case reports, we did not find any reports or epidemiological study regarding this zoonotic infection. This is the first reported case of Brucellosis with pancytopenia from this western province of Iran which has been neglected. Our case was a 16-year-old girl referred with protracted fever during the last month and undetermined diagnosis. She also suffered from generalized pain, pale skin, sweating, anorexia, and weight loss. After clinical surveying, taking history, and physical examination, Brucella infection was suspected. Diagnosis confirmed by standard tube agglutination test (STA), 1/640. The patient was successfully treated with doxycycline, rifampicin, and ceftriaxone

The Experience of Widowed Head of the family during Role Transition: A Qualitative Study

Introduction: Early widowhood causes an increase in stress and health risks in mothers. The objective of this study was to investigate life experiences of these women regarding being the head of the household and its consequences. Method: In this descriptive, exploratory study in-depth interviews were held with 24 widowed parents until achieving data saturation. The data were analyzed using the constant comparative method. Results: The results of data analysis were classified into four main categories: acceptance of the paradoxical identity of a guardian without a guardian, difficulties facing the female head of the household, contexts of difficulties, and female weariness. The subcategories of each category were also determined. Conclusion: The results indicate that lack of attention to widowed female head of the family, who continued to care for their children voluntarily and often in stressful situations, will have negative consequences. Therefore,, beside economical support, they also need the comprehensive support of their family during the process of role transition. Moreover, they need the support of social welfare and social healthcare delivery systems, especially community health nurses, in order to adapt positively to life after the death of their spouse. Keywords: Quality study, Role transition, Support, Widow-headed famil

Relationship between Iron Deficiency Anemia and Febrile Seizures

ObjectiveFebrile seizure is the most common convulsive disorder in childhood. The role of iron in metabolism of neurotransmitters and carrying oxygen to the brain suggests the possibility of a relationship between iron deficiency anemia and febrile seizures.The aim of this study was to investigate the relationship between iron deficiency anemia and febrile seizures.Materials & MethodsThis case - control study was performed on 132 cases and 88 controls, aged 9 months to 5 years, from July 2007 to June 2009 in Baqyiatallah Hospital. Patients were selected using simple random sampling. The case group included children with first febrile seizure (core temperature over 38.5˚C during  seizure) without a central nervous system infection or an acute brain insult. The control group included children suffering from a febrile illness without seizure. Iron deficiency anemia was defined with one of these laboratory indexes: 1) Hemoglobin (Hb) <10.5mg/dl 2) Plasma ferritin <12ng/dl 3) Mean corpuscular volume (MCV) <70  fl. The data collected from patients were analyzed with SPSS.13 software.ResultsLow plasma ferritin was found in 35 cases (26.5%) compared to 26 controls (29.5%), low Hb level was found in 4 cases (3%) compared to 6 controls (6.8%) and low MCV was found in 5 cases (3.8%) compared to 6 controls (6.8%).There was no significant difference in plasma ferritin , Hb level and MCV indices between the two group.ConclusionConsidering the above-mentioned results, there is no relationship between iron deficiency anemia and febrile seizures

Neuromarketing: a review of research and implications for marketing

In this research, we reviewed existing studies which used neuromarketing techniques in various fields of research. The results revealed that most attempts in neuromarketing have been made for business research. This research provides important results on the use of neuromarketing techniques, their limitations and implications for marketing research. We hope that this research will provide useful information about the neuromarketing techniques, their applications and help the researchers in conducting the research on neuromarketing with insight into the state-of-the-art of development methods