فهرست مطالب m zamanzadeh

Orthodontic appliances are usually in contact with the oral mucosa for a long time due to the length of the long-term treatment and are associated with problems due to the continuous contact and friction created. This study was conducted to investigate the epithelial cells of the mucosa of patients with fixed orthodontic appliances.

In this cross-sectional study, smears were collected from three separate areas in 150 patients referred to the dental clinic of Mazandaran University: Area A (slide A): oral mucosa exposed to friction caused by orthodontic brackets, area B (slide B): oral mucosa exposed to friction with the tube on the orthodontic tape and Area C (slide C): oral mucosa without friction, i.e., the lower area of the oral cavity (control area). For histomorphometric analysis, each slide was evaluated with Papanicolaou staining using a light microscope, and the nuclear area (NA), cytoplasmic area (CA), and the ratio of nuclear area to cytoplasmic area (NA/CA) were recorded in square micrometers.

The mean NA was 65.66±22.11, CA was 717.37±1846.53, and NA/CA was 0.037±0.010 square meters. The difference in NA and CA between slides was significant )p<0.001) (slide A

The findings of the study indicate that fixed orthodontic treatment has a significant impact on the nuclear and cytoplasmic area of affected areas compared to non-affected areas. Only some degree of inflammation may be seen in the areas exposed to the orthodontic appliance.

The frequency of patient complaints, and subsequent lawsuits filed by patients against dentists has been on the rise in the recent years. Given the importance of being aware of these issues and preventing them, the purpose of this study was to assess the frequency of dental complaints filed in the Medical Council Organization of three cities of Mazandaran Province (Sari, Babol and Amol) from 2011 to 2019.

This was a descriptive, retrospective, cross-sectional study. Complaints against dentists filed in the Medical Council Organization of three cities of Mazandaran Province (Sari, Babol and Amol) from 2011 to 2019 were retrieved and reviewed. The gender of plaintiffs and defendants, subject of the claim, defendants’ field of expertise, and final verdict were assessed. Data analysis was done using SPSS 19 by the Chi-square test, independent t-test, and Mann-Whitney test.

A total of 120 complaints were retrieved from 2011 to 2019; the highest frequency of complaints was related to 2019 (19.2%). Most complaints were related to Babol city (45%), and the frequency of lawsuits against male dentists was higher than female dentists (P<0.001). The highest frequency of complaints was related to root canal treatment (31.6%), prosthetic treatments (28.3%), and surgical procedures (25.8%).

The highest frequency of complaints was related to Babol city and from dental offices. Also, most complaints were filed against general dentists.

Pregnancy refers to a physiological process associated with body changes, including changes in the oral cavity. Therefore, dental treatments are an integral part of healthcare for pregnant women. The purpose of this study was to evaluate the knowledge and practice of dentists in Bandar Abbas, Iran, regarding the required measures during pregnancy in 2018.

The present descriptive cross-sectional study was conducted on 93 dentists in Bandar Abbas by completing a twenty-item questionnaire about the required measures during pregnancy. Data were analyzed using SPSS16. Chi-square test and t-test were used to statistically analyze the data at the significance level of 0.05.

The mean score of dentistschr('39') knowledge index was 43.86±8.66 (moderate). The level of knowledge was moderate for 59 dentists (63.4%), and only one had a low level of knowledge. In addition, 39 dentists (41.9%) had low, 49 (52.7%) had moderate, and only 5 (5.4%) had a high practice score. None of the demographic factors had a significant relationship with dentistschr('39') knowledge.

Workshops and continuous educational programs are recommended to increase the knowledge of dentists regarding the required measures during pregnancy.

Arsenic is a highly toxic element for human beings, which is generally found in groundwater. Dissolved Arsenic in water can be seen as As+3 and As+5 states. The adsorption process is one of the available methods to remove Arsenic from aqueous solutions. Thus, this papers aims at removing Arsenic (III) from aqueous solutions through adsorption on iron oxide granules. The relation among four independent variables, namely the initial concentration of Arsenic (III), pH, adsorbent dose, and contact time have been investigated through Response Surface Methodology. Design-Expert software and Central Composite Design method have been used to design and analyze the experiments and results. Also, SEM and FTIR analysis have been conducted to characterize the absorbent morphology. The optimum initial concentration of Arsenic (III), pH, contact time, and adsorbent dosage are 30ppm, 5, 49.99min, and 8g/l, respectively. Under these optimum conditions, the Arsenic (III) removal efficiency is 67%. The predicted 2FI model shows the highest Arsenic removal coefficient (R2=0.887).

Traumatic dental injuries (TDIs) are among the urgent challenges in dental sciences. These types of trauma are a common dental health problem, which may affect hard tissues and tooth-supporting structures. Since dentists’ knowledge and practice are vital for TDI treatments, this study aimed to assess the levels of knowledge of TDIs among general dentists working in Bandar Abbas, Iran.

This cross-sectional study was conducted on 97 general dentists working in the city of Bandar Abbas, Iran, using a three-part questionnaire comprising items about demographic characteristics, knowledge of TDI causes, and knowledge of TDI treatments. Descriptive and analytical statistical analyses of data were performed according to Mann-Whitney and Kruskal-Wallis tests using SPSS 20 software at the significance level of 0.05.

Ninety-seven general dentists, including 61 men and 36 women, participated in this study. The findings revealed that 60.9% and 46.4% of these dentists had high levels of knowledge about TDI causes and treatments, respectively. The mean score obtained by the general dentists was 11.86±2.87, which was promising. A significant relationship was observed between university affiliation and levels of knowledge (P=0.002).

According to the results, knowledge about common causes and treatments of TDI was at a favorable level among the general dentists working in Bandar Abbas. There was a significant relationship between university affiliation and levels of knowledge; dentists who graduated from universities located in the city of Tehran, Iran, had higher levels of knowledge than others did.

Surface water and underground water quality in countries that facing dehydration have increased the interest of the community to use Household Water Treatment devices. The aim of this study was the evaluation of the quality of drinking water of Household Water Treatment devices and general distribution network in Garmsar, which is under the control of the water safety plan.

A descriptive cross-sectional study administered in 6 regions and 41 cities of Garmsar city in spring and summer seasons in 2018. Chemical tests performed according to the standard methods for the examination of water and wastewater, general measurements were performed using the multi-tube fermentation method and counting of heterotrophic bacteria by pour plate method. The results analyzed by using Excel and SPSS software.

The average values during two seasons were reported as: EC= 1507 (μS/cm), TDS= 786.8 (mg/L), F= 0.048 (mg/L), residual free chlorine= 0.67 (mg/L), pH=7.9, total coliform= 0.16 (MPN/100 mL), fecal coliform= 0.14 (MPN/100 mL) and HPC= 112 (CFU/mL). No significant difference found between the chemical and microbial parameters in the general distribution network and the output of the Household Water Treatment devices during the two seasons.

Household water treatment devices did not affect the microbial burden but caused a change in the amounts of some chemical parameters. Drinking water from the distribution network, with the proper application of the water safety plan, is of good quality.

The clastics Paleozoic Era deposits especially the Zakeen and Faraghan formations in some locations of the Arabian Plate host hydrocarbon reservoirs, but reservoir potential of these formations has never studied in north of this plate and the central part of Persian Gulf. The Zakeen Formation (Givetian to Famennian) completely studied for the first time in one exploration well in the Persian Gulf  Basin. Studied section is located on the north-east of the Arabian Plate and is the thickest reported section of the Zakeen Formation. It rest unconformably on Sarchahan Formation (Silurian) and it is coverd by clastics of the Faraghan Formation (Lower Permian). This study has investigated petrofacies and microfacies, diagenetic properties and depositional environments of  the Zakeen Formation by studying thin sections prepared from cuttings in one well in the central part of Persian Gulf. Results show that the Zakeen Formation is composed of quartz arenite, sub-arkose, arkose, siltstone, claystone, mudstone petrofacies and carbonate mudstone microfacies. Based on sedimentary propertiesand Palynofacies results, the Zakeen Formation was deposited on clastic shallow marine environment consists of beach plain, shoreface and offshore sub-environments. Main diagenetic processes include compaction, cementation (silisic, carbonate, pyrite and iron oxide), feldspar alteration, sericitization, neomorphism and dolomitization. Heterogeneity of the Zakeen lithology and variety of environmental conditions and diagenetic features created favorable conditions for reservoir feasibility studies.

Introduction The faults of the northern section of Qom-Zafreh fault system with right-lateral right-angled movements, along with its often reversed components, also comprise the northern parts of the central Iran's zone. In this research, seismic potential and tectonic stresses of this fault system are investigated based on geomorphometric and morphotectonic methods. Field data and morphotectonic evidence in the area have been used to adapt the data. To this end, the measurement of some geomorphic indices and their adaptation to the location of the main faults were used. These indicators, which are most widely used in the tectonics and neotectonic evaluation studies, are: First category (level-level indicators). Second category) Indices related to the catchment basin dynamics. On the one hand, the characteristics of the mentioned indices are, on the one hand, their sensitivity to the movements of sliding and steady-state faults and, on the other hand, the reason for the predominance of deformed phenomena in relation to the erosion phenomena in the region. To calculate geomorphic indices in 18 sub-basins in the study area, the TecDEM extension program was also used. The initial results indicate the high tectonic activity near the main faults of the northern part of the Qom-Zafare zone such as Bidadeh fault, Qom fault, Kashan fault, and .... These findings are consistent with landforms and are consistent with tectonic practices existing at the region. Materials and methods In this research, the seismic potential and tectonic activity of the northern section of the Qom-Zafare fault system have been evaluated using geomorphometric and morphotectonic methods in the sub-basins of the study area. In order to investigate the tectonic activity, the study area was divided into 18 sub-basins. Then, to measure and evaluate the tectonic activities of the study area, measurements of geomorphic indices and their adaptation to the location of the main faults were used. In order to calculate the geomorphic indices of the study area, they were classified into two general categories: 1) Dynamic indicators of the surface which are: longitudinal gradient (SL), sine wave of the mountain front (Smf) and valley width to valley height ( Vf). 2) Dynamic catchment indicators of the catchment area that are as follows: drainage basin asymmetry (Af), hypsometric integral (Hi) and drainage basin shape (Bs). To improve and improve the quality of measuring the tectonic and neotectonic indices, the computational capability of the TecDEM software, which is an add-on, is used in the Matlab software environment. After extraction, the results of the geomorphic indices were separated into ArcGIS environment by separate study basins of each study area and then the tectonic activity index (Iat) was obtained. Based on the obtained values from the active land development index (IAT), the five study areas were very active, active, moderate, and low activity and very low activity. Results and discussion The study area includes the northern section of Qom-Zefreh fault zone, which includes a large part of the Qom province. This zone extends from the east and south-east to the Central Iran zone and from the north to the Alborz zone and from the west and southwest to Sanandaj Zone of Garrison. In general, there are active tectonic processes and seismic faults in the northwest-southeastern region. Measurements and investigation of the evidence of the activity of faults in quaternary sediments indicate the change in the process of these faults and cause the alteration of these faults to be generally right-angled, although the left-handed movements in some of the secondary or non-essential faults are due to Their orientation is seen in relation to the main stress (Morley et al., 2009; Orang et al., 1393; Pourkermani et al., 2012; Eliaszadeh et al., 2012). Conclusion In order to conclude and evaluate the seismic potential and tectonic activity in this part of the Qom-Zefref fault zone, these indicators are divided into two general categories: dynamic and dynamic indicators of catchment basins, then by the relative activity index Iat They were classified into three categories (Table 1). Finally, by integrating the Iat index layer and other information layers, including the deformation of the main faults and the intensity of seismic centers in the ArcMap10.3 software environment, based on seismicity and tectonic activity, five classes: very low, low, moderate, high And were classified very much and the seismic potential zonation map and tectonic activities of the study area were extracted. In this research, for the first time, geomorphic indices for zoning seismicity and tectonic activities in terms of the relative tectonic activity index of Iat, in contrast to other studies using only geological parameters (lithology), are used.

Bacterial contamination of clinical surfaces of dental units that have been touched or been exposed to patients’ blood or saliva can be a reservoir for infections, leading to cross-contamination. This study aimed to evaluate bacterial contamination in the clinical environment of Sari Dental School in 2018.

In this cross-sectional (descriptive-analytical) study,
samples were randomly collected from 15 active dental units of five departments of Sari Dental School, including surgical, pediatrics, prosthodontics, endodontics, and restorative dentistry departments. Samples were collected from headrests, light handles, and dental seats using moist sterile swabs, and air samples were collected using agar plates. Sampling was carried out before and after dental practice. The samples were transferred to the microbiology laboratory to determine the number of various microorganism colonies. Data were analyzed using Chi-square, McNemar, and Kruskal-Wallis tests. P-values lower than 0.05 were considered significant.

A significant difference was found between the frequency of contamination before and after clinical practice based on McNemar test results. Staphylococci were more prevalent on the surfaces. Kruskal-Wallis test revealed no significant difference in the total number of microorganisms between different departments after dental practice. Bacterial contamination of air was greater than other parts, followed by dental seats.

Microbial contamination of dental units considerably increases after treatment of each patient. Therefore, disinfection of dental unit surfaces and seats between each patient is essential. Also, methods of infection control must be supervised to prevent cross-infection.

S‌o‌i‌l s‌t‌r‌e‌n‌g‌t‌h p‌r‌o‌p‌e‌r‌t‌i‌e‌s a‌r‌e i‌n‌h‌e‌r‌e‌n‌t‌l‌y v‌a‌r‌i‌a‌b‌l‌e, d‌u‌e t‌o t‌h‌e n‌a‌t‌u‌r‌e o‌f t‌h‌e‌i‌r f‌o‌r‌m‌a‌t‌i‌o‌n. S‌l‌o‌p‌e s‌t‌a‌b‌i‌l‌i‌t‌y p‌r‌o‌b‌l‌e‌m‌s a‌r‌e a‌m‌o‌n‌g t‌h‌e m‌o‌s‌t i‌m‌p‌o‌r‌t‌a‌n‌t i‌s‌s‌u‌e‌s i‌n g‌e‌o‌t‌e‌c‌h‌n‌i‌c‌a‌l e‌n‌g‌i‌n‌e‌e‌r‌i‌n‌g, a‌n‌d t‌h‌e‌y a‌r‌e i‌n‌v‌e‌s‌t‌i‌g‌a‌t‌e‌d i‌n t‌h‌i‌s s‌t‌u‌d‌y c‌o‌n‌s‌i‌d‌e‌r‌i‌n‌g t‌h‌e e‌f‌f‌e‌c‌t o‌f h‌e‌t‌e‌r‌o‌g‌e‌n‌e‌i‌t‌y a‌n‌d a‌n‌i‌s‌o‌t‌r‌o‌p‌y o‌f s‌o‌i‌l s‌t‌r‌e‌n‌g‌t‌h p‌r‌o‌p‌e‌r‌t‌i‌e‌s i‌n l‌o‌n‌g t‌e‌r‌m b‌e‌h‌a‌v‌i‌o‌r. T‌o t‌h‌i‌s a‌i‌m, t‌h‌e r‌a‌n‌d‌o‌m f‌i‌e‌l‌d t‌h‌e‌o‌r‌y c‌o‌m‌b‌i‌n‌e‌d w‌i‌t‌h t‌h‌e f‌i‌n‌i‌t‌e d‌i‌f‌f‌e‌r‌e‌n‌c‌e m‌e‌t‌h‌o‌d h‌a‌s b‌e‌e‌n a‌d‌o‌p‌t‌e‌d i‌n t‌h‌e f‌r‌a‌m‌e o‌f M‌o‌n‌t‌e-C‌a‌r‌l‌o s‌i‌m‌u‌l‌a‌t‌i‌o‌n‌s. T‌h‌e f‌a‌c‌t‌o‌r o‌f s‌a‌f‌e‌t‌y o‌f t‌h‌e s‌l‌o‌p‌e h‌a‌s b‌e‌e‌n c‌a‌l‌c‌u‌l‌a‌t‌e‌d b‌y t‌h‌e $C-p‌h‌i$ r‌e‌d‌u‌c‌t‌i‌o‌n m‌e‌t‌h‌o‌d a‌n‌d t‌h‌e p‌r‌o‌b‌a‌b‌i‌l‌i‌t‌y o‌f f‌a‌i‌l‌u‌r‌e h‌a‌s t‌h‌e‌n b‌e‌e‌n i‌n‌v‌e‌s‌t‌i‌g‌a‌t‌e‌d t‌h‌r‌o‌u‌g‌h M‌o‌n‌t‌e-C‌a‌r‌l‌o s‌i‌m‌u‌l‌a‌t‌i‌o‌n‌s. D‌i‌f‌f‌e‌r‌e‌n‌t s‌t‌o‌c‌h‌a‌s‌t‌i‌c p‌a‌r‌a‌m‌e‌t‌e‌r‌s w‌e‌r‌e c‌o‌n‌s‌i‌d‌e‌r‌e‌d i‌n o‌r‌d‌e‌r t‌o s‌t‌u‌d‌y t‌h‌e‌i‌r e‌f‌f‌e‌c‌t o‌n t‌h‌e s‌t‌a‌b‌i‌l‌i‌t‌y o‌f n‌a‌t‌u‌r‌a‌l s‌l‌o‌p‌e‌s i‌n l‌o‌n‌g t‌e‌r‌m s‌c‌h‌e‌m‌e‌s o‌r u‌n‌d‌e‌r d‌r‌a‌i‌n‌e‌d c‌o‌n‌d‌i‌t‌i‌o‌n‌s. T‌h‌e c‌o‌e‌f‌f‌i‌c‌i‌e‌n‌t o‌f v‌a‌r‌i‌a‌t‌i‌o‌n o‌f t‌h‌e c‌o‌h‌e‌s‌i‌o‌n a‌n‌d i‌n‌t‌e‌r‌n‌a‌l f‌r‌i‌c‌t‌i‌o‌n a‌n‌g‌l‌e r‌e‌p‌r‌e‌s‌e‌n‌t‌i‌n‌g s‌t‌r‌e‌n‌g‌t‌h p‌r‌o‌p‌e‌r‌t‌i‌e‌s, s‌c‌a‌l‌e o‌f f‌l‌u‌c‌t‌u‌a‌t‌i‌o‌n o‌f t‌h‌e p‌a‌r‌a‌m‌e‌t‌e‌r‌s, c‌r‌o‌s‌s c‌o‌r‌r‌e‌l‌a‌t‌i‌o‌n b‌e‌t‌w‌e‌e‌n s‌t‌r‌e‌n‌g‌t‌h p‌a‌r‌a‌m‌e‌t‌e‌r‌s a‌n‌d h‌e‌t‌e‌r‌o‌g‌e‌n‌e‌i‌t‌y a‌n‌i‌s‌o‌t‌r‌o‌p‌y, a‌r‌e a‌m‌o‌n‌g a‌l‌l s‌t‌o‌c‌h‌a‌s‌t‌i‌c p‌a‌r‌a‌m‌e‌t‌e‌r‌s i‌n‌v‌e‌s‌t‌i‌g‌a‌t‌e‌d i‌n t‌h‌i‌s s‌t‌u‌d‌y. T‌h‌r‌e‌e d‌i‌f‌f‌e‌r‌e‌n‌t v‌a‌l‌u‌e‌s o‌f 10, 50 a‌n‌d 90 f‌o‌r t‌h‌e C‌o‌V o‌f p‌a‌r‌a‌m‌e‌t‌e‌r‌s w‌e‌r‌e c‌o‌n‌s‌i‌d‌e‌r‌e‌d, i‌n o‌r‌d‌e‌r t‌o c‌o‌v‌e‌r b‌o‌t‌h l‌o‌w a‌n‌d h‌i‌g‌h v‌a‌r‌i‌a‌b‌i‌l‌i‌t‌y. D‌i‌f‌f‌e‌r‌e‌n‌t v‌e‌r‌t‌i‌c‌a‌l c‌o‌r‌r‌e‌l‌a‌t‌i‌o‌n l‌e‌n‌g‌t‌h‌s, r‌a‌n‌g‌i‌n‌g f‌r‌o‌m 0.1 t‌o 50m, a‌r‌e c‌o‌n‌s‌i‌d‌e‌r‌e‌d t‌o c‌o‌v‌e‌r a w‌i‌d‌e r‌a‌n‌g‌e, f‌r‌o‌m f‌u‌l‌l‌y u‌n‌c‌o‌r‌r‌e‌l‌a‌t‌e‌d t‌o f‌u‌l‌l‌y c‌o‌r‌r‌e‌l‌a‌t‌e‌d p‌a‌r‌a‌m‌e‌t‌e‌r‌s. T‌h‌e F‌i‌r‌s‌t O‌r‌d‌e‌r S‌e‌c‌o‌n‌d M‌o‌m‌e‌n‌t (F‌O‌S‌M), t‌h‌e F‌i‌r‌s‌t O‌r‌d‌e‌r R‌e‌l‌i‌a‌b‌i‌l‌i‌t‌y M‌e‌t‌h‌o‌d (F‌O‌R‌M), a‌n‌d t‌h‌e R‌a‌n‌d‌o‌m F‌i‌n‌i‌t‌e D‌i‌f‌f‌e‌r‌e‌n‌c‌e M‌e‌t‌h‌o‌d (R‌F‌D‌M) w‌e‌r‌e a‌d‌o‌p‌t‌e‌d t‌o i‌n‌v‌e‌s‌t‌i‌g‌a‌t‌e t‌h‌e p‌r‌o‌b‌a‌b‌i‌l‌i‌t‌y o‌f f‌a‌i‌l‌u‌r‌e. T‌h‌e l‌a‌t‌t‌e‌r w‌a‌s i‌n‌v‌o‌k‌e‌d b‌y a c‌o‌m‌b‌i‌n‌a‌t‌i‌o‌n o‌f r‌a‌n‌d‌o‌m f‌i‌e‌l‌d t‌h‌e‌o‌r‌y w‌i‌t‌h t‌h‌e f‌i‌n‌i‌t‌e d‌i‌f‌f‌e‌r‌e‌n‌c‌e m‌e‌t‌h‌o‌d t‌h‌r‌o‌u‌g‌h M‌o‌n‌t‌e-C‌a‌r‌l‌o s‌i‌m‌u‌l‌a‌t‌i‌o‌n‌s b‌y F‌I‌S‌H p‌r‌o‌g‌r‌a‌m‌m‌i‌n‌g i‌n F‌L‌A‌C s‌o‌f‌t‌w‌a‌r‌e. T‌h‌e r‌e‌s‌u‌l‌t‌s s‌h‌o‌w t‌h‌a‌t c‌o‌n‌s‌i‌d‌e‌r‌i‌n‌g h‌e‌t‌e‌r‌o‌g‌e‌n‌e‌i‌t‌y c‌a‌u‌s‌e‌s v‌a‌r‌i‌a‌b‌i‌l‌i‌t‌y i‌n r‌e‌s‌u‌l‌t‌s. T‌h‌e c‌o‌e‌f‌f‌i‌c‌i‌e‌n‌t o‌f v‌a‌r‌i‌a‌t‌i‌o‌n a‌n‌d t‌h‌e s‌c‌a‌l‌e o‌f f‌l‌u‌c‌t‌u‌a‌t‌i‌o‌n h‌a‌v‌e b‌e‌e‌n f‌o‌u‌n‌d t‌o h‌a‌v‌e t‌h‌e m‌o‌s‌t e‌f‌f‌e‌c‌t o‌n t‌h‌e p‌r‌o‌b‌a‌b‌i‌l‌i‌t‌y o‌f f‌a‌i‌l‌u‌r‌e. W‌h‌e‌n t‌h‌e c‌o‌e‌f‌f‌i‌c‌i‌e‌n‌t o‌f v‌a‌r‌i‌a‌t‌i‌o‌n o‌f s‌h‌e‌a‌r s‌t‌r‌e‌n‌g‌t‌h p‌a‌r‌a‌m‌e‌t‌e‌r‌s i‌n‌c‌r‌e‌a‌s‌e‌s, t‌h‌e m‌e‌a‌n f‌a‌c‌t‌o‌r o‌f s‌a‌f‌e‌t‌y d‌e‌c‌r‌e‌a‌s‌e‌s, a‌n‌d t‌h‌e p‌r‌o‌b‌a‌b‌i‌l‌i‌t‌y o‌f f‌a‌i‌l‌u‌r‌e i‌n‌c‌r‌e‌a‌s‌e‌s. T‌h‌e v‌e‌r‌t‌i‌c‌a‌l s‌c‌a‌l‌e o‌f f‌l‌u‌c‌t‌u‌a‌t‌i‌o‌n o‌f p‌a‌r‌a‌m‌e‌t‌e‌r‌s i‌n‌d‌u‌c‌e‌s a‌n i‌n‌c‌r‌e‌a‌s‌e i‌n v‌a‌r‌i‌a‌n‌c‌e f‌u‌n‌c‌t‌i‌o‌n, d‌u‌e t‌o i‌t‌s i‌n‌c‌r‌e‌a‌s‌e u‌p t‌o a c‌r‌i‌t‌i‌c‌a‌l v‌a‌l‌u‌e. F‌u‌r‌t‌h‌e‌r‌m‌o‌r‌e, i‌t s‌e‌e‌m‌s t‌h‌a‌t c‌r‌o‌s‌s c‌o‌r‌r‌e‌l‌a‌t‌i‌o‌n h‌a‌s l‌e‌s‌s e‌f‌f‌e‌c‌t o‌n v‌a‌r‌i‌a‌t‌i‌o‌n‌s o‌f t‌h‌e f‌a‌c‌t‌o‌r o‌f s‌a‌f‌e‌t‌y o‌f n‌a‌t‌u‌r‌a‌l s‌l‌o‌p‌e‌s.