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Introduction Podiform chromite deposits are small magmatic chromite bodies formed in the lower section of an ophiolite complex. Podiform chromite mines have produced 57.4 percent of the world’s total chromite production. Most ore bodies are irregularly dispersed and relatively small, between 0.0004 and 1 Mt, averaging 0.011 Mt (United States Geological Survey, 2012), and reserves greater than 1Mt are most uncommon (Evans, 1998). The Khoy ophiolite covers an extensive area in the northwest of Iran along the Iran-Turkey border. This ophiolite zone comprises one of the most promising areas for prospecting of chromite deposits as a result of extensive outcrops of ultramafic rocks. The Kochuk area is located in the western domain of the Khoy ophiolite (Fig. 1). Some geological and geochemical investigations have been carried out for recognition of chromite deposits in this area by the authors during the last 15 years. The geological criteria of prospecting for chromite deposits from the Khoy ophiolite are discussed in this study. Materials and methods In this research, geological methods were used to identify chromite deposits in the Khoy ophiolite. Geological surveys at scale of 1:20000 were implemented in an area of about 70 km2. Lithogeochemical sampling (eighty five samples), petrography (five samples), ore microscopy (eighteen samples) and sampling for determination of specific gravity of ore (eleven samples) were performed in these study. Testing of bedrock mineralization was performed in a relatively straightforward manner by sampling of outcrops in areas where chromite orebodies cropped out or were underlain below a thin soil cover. In contrast, chromite mineralization prospecting in locations with thick cover were carried out by pitting and trenching. Chemical analysis of the samples was carried out by the XRF method in the Kansaran Binaloud laboratory. Results In this study, geological mapping allows discrimination of ophiolite lithologies (ultramafic rocks, chromitite, basaltic pillow lava, gabbro-diorite, ophiolite mélange, listwaenite and other associated rocks). Ultramafic rocks are important in prospecting for chromite mineralization. Geological prospecting led to the identification of a chromite ore field with a remarkable potential since more than 20 chromite orebodies were recognized. Five mineralized zones called A, B, C, D, E and 13 chromite indices were recognized in the Kochuk chromite field. The A zone is located almost in the central part of the study area. Four ore bodies have been recognized in this zone. The A1 orebody extended by 68 meters in length and 6-9 m in thickness. This subzone is characterized by a lenticular shape with an east-west-trending strike (N115S) and a 60o dipping toward THE south. The B zone is located at ~2.9 km west of the A zone. The B1 orebody consists of the largest known chromite orebody in this area which comprises N120S-trending and 50 NW dipping lenticular geometry extended by 118 meters in length. The thickness of the B1 orebody varies between 6 and 12 meters averaging around seven meters. There are three chromite orebodies recognized as C1, C2, and C3 subzones in the C zone. The C1 orebody is composed of 74 meter-long lens with variable thickness between 3.5 and 9 meters. It has a N40E-trending strike, which dips 45-50 degrees to the west. In the D zone, three small chromite orebodies have been identified. The D1 orebody consists of a 20 meter-long lens ranging from 1 to 5 (avg. 3.5) meters in thickness. This orebody is oriented by a N160S in strike and a 50 NE in dip. The chromitite occurrences have lenticular, tubular and vein-like shapes host by hurzburgite. Rocks of the upper mantle-lower crust transition zone and probably the associated chromite deposits have not been recognized yet in this area (Imamalipour, 2011). The typical ore textures consist of disseminated, nodular, massive, banded and cataclastic. Discussion Exploration of podiform chromite deposits has been a challenge due to their unpredictable occurrence, the small size of most orebodies and the intensive tectonic dislocations (United States Geological Survey, 2012). Moreover, the absence of primary geochemical halos and associated alteration are matters that have led to difficulties in prospecting for podiform chromites. Chromite as an accessory mineral is associated with harzburgite host rocks. This mineral is released during the weathering process and is accumulated within the stream sediment heavy minerals. Therefore, application of the stream sediment geochemistry method may not necessarily result in useful information for determining the location of chromite outcrops. In this study, geological methods were used for podiform chromites prospecting which culminated valuable results. The Kochuk chromite-bearing area was recognized as a chromite ore field in the western city of Khoy. The most important geological criteria of prospecting for chromite deposits from the Khoy ophiolite are: 1) chromite bodies are surrounded by dunite envelopes with variable thickness; 2) the recognized chromite-rich zones are mainly located near gabbroic intrusions; 3) most chromite lenses are oriented along an east–west trend; 4) the existence of chromite fragments on stream beds can be considered to be a suitable sign to define the entry of these anomalous rocks to the stream sediment; 5) morphologically, chromite outcrops often occur protruding from the host rock because of their higher resistance to erosion. This can facilitate the recognition of their outcrops; 6) chromite bearing zones usually do not have or exhibit thin vegetation cover despite the high rate of annual rainfall; 7) outcrops of disseminated ores can indicate the presence of high grade chromite ore in the sub surface parts; 8) the main oxide contents of chromite ores vary from an individual ore body to another one. References Evans, A.M., 1998. An introduction to economic geology and its environmental impacts. Blackwell Science, United Kingdom, 376 pp. Imamalipour, A. 2011. Geochemistry and geological setting of chromitites of Aland area from the Khoy ophiolite complex, NW Iran. Geosciences, 20(80): 47–56. (in Persian with English abstract) United States Geological Survey, 2012. Podiform chromite deposits, database and grade and tonnage models. United States Geological Survey, Virginia, Scientific Investigations Report 2012–5157, 45 pp.

Background and purpose: Nowadays, social networks are considered as the major communication tools in communities and throughout the world. This study aimed at investigating the pattern of social network use in medical students who will have important occupations in healthcare system. Materials and methods: This descriptive-analytical study was carried out in 715 medical students in Mazandaran University of Medical Sciences, Sari, Iran 2018. Information on the frequency and pattern of social network use were collected and data were analyzed in SPSS V21. Results: The mean age of students was 21.59±2.7 years old and 711 students (99.4%) were engaged with social networks. The daily median use of social networks was 3 hours. The most common reason for using these networks were communication with friends (40.45%). The average hours of using these networks were significantly higher in single students compared with those of married ones (P

Bacterial outer membrane vesicles (OMVs) are increasingly used as carriers for drug delivery. Here the authors encapsulate biopolymer melanin into OMVs, extending their use to optoacoustic imaging both in vitro and in vivo, and demonstrate the potential of this tool for photothermal therapy applications.

Background and purpose: Hyperbilirubinemia is the most common cause of neonatal hospitalization and can be a sign of urinary tract infection during infancy. Urinary tract infection (UTI) is one of the reasons for prolonged jaundice. This research aimed at studying the prevalence of urinary tract infection in neonates with hyperbilirubinemia admitted to Tonekabon Shahid Rajaei Hospital, 2015. Materials and methods: This cross-sectional study was conducted in 259 infants. The samples were selected by census method. To diagnose the urinary tract infection, urine with a 2-cc syringe was taken by pediatrician through suprapubic method. Data were analyzed by Chi-square test. Results: UTI was identified in 18 (6.9%) neonates, including 10 (55.5%) boys and 8 (44.4%) girls. Urine culture revealed 12 E. coli spp. and 6 Proteus spp. Also, in 49 (91.18%) were found to have prolonged jaundice. Conclusion: Due to the prevalence of UTI in neonates, urine culture is suggested in all infants hospitalized for jaundice even in those without prolonged jaundice.

Contrast enhancement in optoacoustic (photoacoustic) imaging can be achieved with agents that exhibit high absorption cross-sections, high photostability, low quantum yield, low toxicity, and preferential bio-distribution and clearance profiles. Based on advantageous photophysical properties of croconaine dyes, we explored croconaine-based nanoparticles (CR780RGD-NPs) as highly efficient contrast agents for targeted optoacoustic imaging of challenging preclinical tumor targets. Initial characterization of the CR780 dye was followed by modifications using polyethylene glycol and the cancer-targeting c(RGDyC) peptide, resulting in self-assembled ultrasmall particles with long circulation time and active tumor targeting. Preferential bio-distribution was demonstrated in orthotopic mouse brain tumor models by multispectral optoacoustic tomography (MSOT) imaging and histological analysis. Our findings showcase particle accumulation in brain tumors with sustainable strong optoacoustic signals and minimal toxic side effects. This work points to CR780RGD-NPs as a promising optoacoustic contrast agent for potential use in the diagnosis and image-guided resection of brain tumors.

Purpose -- The purpose of this paper is to analyze the keywords used in peer-reviewed literature on green supply chain management. Design/methodology/approach -- To determine the keywords that were used in this area, an analysis of 629 papers was conducted. The papers were identified through searches of 13 keywords on green supply chains. Trends in keyword usage were analyzed in detail focusing on examining variables such as the most frequently used journals/keywords, their frequencies, citation frequency and research contribution from different disciplines/countries. Findings -- A number of different terms have been used for research focused on the environmental impacts of supply chains, including green supply chains, sustainable supply chains, reverse logistics and closed-loop supply chains, among others. The analysis revealed that the intensity of research in this area has more than tripled in the past six years and that the most used keyword was "reverse logistics". The use of the terms "green supply chains" and "sustainable supply chains" is increasing, and the use of "reverse logistics" is decreasing. Research limitations/implications -- The analysis is limited to 629 papers from the Scopus database during the period of 2007 and 2012. Originality/value -- The paper presents the first systematic analysis of keywords used in the literature on green supply chains. Given the broad array of terms used to refer to research in this area, this is a needed contribution. This work will help researchers in choosing keywords with high frequency and targeting journals for publishing their future work. The paper may also provide a basis for further work on developing consolidated definitions of terms focused on green supply chain management. [ABSTRACT FROM AUTHOR]