Sub-communities within this community

Recent Submissions

  • Benthic assemblages for ecological evaluation of Bardawil Lagoon, Mediterranean Sea, ‎Egypt.

    El komi, Mohamed Mohamed (2019-12-31)
    Bardawil Lagoon is the only highly saline oligotrophic lagoon in Egypt, has an area of ca. ‎‎650 km2 with water depths ranged 0.3m to 3m and economically important in terms of ‎fish production. It is the optimum zone getting migratory birds in winter. It is separated ‎from the Mediterranean Sea by a narrow sandy shelf (90 km length, and 22 km width). ‎Ecological evaluation of benthic communities in Bardawil Lagoon to follow-up study of ‎the distribution of benthic study at 12 selected sampling sites representing different ‎environmental habitats for long periods through the project of Environmental Study ‎Wetlands OF North Egyptians Lakes where samples were collected seasonally (2010-‎‎2015) and semi-annually (2015 - 2019). The results and data analysis indicated that the ‎distribution, composition and dominance of macro benthic organisms in Lake Bardawil ‎were composed mainly of Ostracoda, Polychaeta, Sea grasses, Bivalvia, Insecta larvae‏ ‏communities‏ ‏and dominated the constituent of bottom fauna. The variations in the ‎benthic biomass were the heaviest at sites elRaodh and meddle elRaodh representing ‎‎1354 and 1105 g/m2 which corresponding respectively to 18.2 % and 14.9% of the ‎annual average of benthic biomass (619 g/m2). Regional variations abundance of the ‎benthic structure was highest at sites elTelol and elRaodh representing 3486 ind/m2 and ‎‎3635 ind/m2 which corresponding respectively to 14.8% and 15.3% of the annual ‎average of benthic density (1978 ind/m2). Sites of sampling study were evenly spread (J’ ‎‎> 0.8) at most sites except at elTelol and elRaodh also, high diversity (H’ > 3.00) was at ‎the most sites and show lower value at sites elTelol, elGals, Boughaz I, elNaser, and ‎Raba`a while, Swartz Dominance indexes of number of 5 species over 75% showed low ‎values at sites elGals, Boughaz I, elNaser, and Raba`a. The abiotic environmental effects ‎in the Bardawil Lagoon are general to those generally observed in other areas influenced ‎by organic wastes, namely, changed in the physic-chemical properties of the sediments ‎and low oxygen concentrations in the bottom water due to decomposition of organic ‎materials.‎
  • Biometric properties of euryhaline fish the sand smelt Atherina boyeri Risso, ‎‎1810‎.

    Benzer, Semra (2019-06-30)
    In this study the presence of sand smelt Atherina boyeri Risso, 1810, an invasive and ‎translocated species has been reported in the Hirfanlı Dam Lake, Turkey. The fish ‎samples were collected from the fishermen operating in the area in April 2016. Twenty-‎three morphometric characteristics of A. boyeri, were taken, including standard length ‎‎(SL), fork length (FL), total length (TL), preorbital distance, eye diameter, interorbital ‎distance, head length, head width, dorsal fin I nose point distance, dorsal fin II nose ‎point distance, preanal distance, prepectoral distance, preventral distance, dorsal fin I ‎base length, dorsal fin II base length, anal fin base length, pectoral fin base length, ‎ventral fin base length, maximum body height, caudal peduncle height, body width, ‎caudal peduncle width, body weight (W). The SL varied between 62 to 75 mm and ‎weight 2.324 to 4.133 g in females. Whereas in males the SL varied between 56 to78 mm ‎and weight 1.533 to 4.011 g. The sex ratio was slightly in favour of females being 54.4%‎
  • Feeding habits of pick handle barracuda (Sphyraena jello) Cuvier, 1829 along the coast ‎of Pakistan‎.

    Manzoor, Hina; Zohra, Kashifa; Osmany, Hamid Badar (2019-06-30)
    A one year combined study of both sexes was conducted from March 2017 to February ‎‎2018 to investigate the feeding habit of Pick handle Barracuda (Sphyraena jello) Cuvier, ‎‎1829 locally called as Safaid kund along the coast of Pakistan, a large species found in ‎Pakistani water caught mainly by bottom set gillnet throughout the year. Samples ‎studied at Karachi fish harbor, in commercial catch which is the major landing center of ‎Pakistan. During this counting method was applied with naked eye. Mostly fishes ‎characterized by 91.66%, cephalopod 5.66% and shrimp 2.78% made the highest and ‎lowest stomach content respectively shoes carnivorous behavior of the species. ‎
  • Determination of mercury (Hg) in two sea cucumber species Ohshimella ehrenbergii ‎‎(Selenka, 1868) and Stolus buccalis (Stimpson, 1855) from the Karachi ‎coast.

    Ahmed, Quratulan; Bat‎, Levent; Ali, Qadeer Mohammad (2019-06-30)
    In this study the amounts of mercury (Hg) were determined in tentacles and muscle ‎tissues of O. ehrenbergii and S. buccalis from two coastal sites of Karachi; Buleji and ‎Sunehri during Southwest monsoon (August and September) and Northeast monsoon ‎‎(December and January) seasons of the year 2018. The mean amounts of Hg in edible ‎tissues of sea cucumbers were as follows: O. ehrenbergii (0.0176 mg/kg dry wt.) and S. ‎buccalis (0.0155 mg/kg dry wt.). Hg amounts in muscles of both species are much lower ‎than the maximum permissible limits (0.5 mg/kg wet wt.). Estimated Daily Intakes for ‎adults consuming O. ehrenbergii and S. buccalis are lower than published RfD values. ‎Total Target Hazard Quotient (TTHQ) values (0.00787) are also lower than 1, it may be ‎concluded that the consumption of these sea cucumbers from Karachi, do not pose any ‎health hazards to human as Hg amounts were concerned.‎
  • Interspecific isozyme variability in Porcellanid crabs (Crustacea: Decapoda: Anomura) ‎from the coastal waters of Pakistan.‎

    Naz, Farah; Odhano, Sahir; Saher, Noor Us; Kamal, Mustafa (2019-06-30)
    Polyacrylamide gel electrophoresis was used to investigate the interspecific isozyme ‎variability among three species of Porcellanid crabs: Petrolisthes ornatus, P. rufescens ‎and P. boscii from the coastal waters of Karachi, Pakistan. Seven enzyme systems and ‎the general protein (non-specific) were examined for genetic variations. Among the three ‎species; Nei's heterozygosity for overall loci was observed (0.067), whereas Shannon’s ‎information Index (I) for genetic variations based on the heterozygosity was (0.055) in ‎three species of Genus Petrolisthes. Species were differentiated from each other as Nei’s ‎genetic distance ranged in between 0.0093- 0.0314. The genetic relationship among the ‎three species of genus Petrolisthes similar from those inferred from morphological ‎features.‎
  • Morphometric characteristics of Indian mackerel (Rastrelliger kanagurta) landing at ‎three fish harbors of Baluchistan, Pakistan.

    Roonjha, Asif Ali; Bano, Azra; Siddique, Saima; Rasheed, Shazia‎ (2019-06-30)
    In the present study fifteen morphometric characters of Indian mackerel, Rastrelliger ‎kanagurta were studied. Collections were made from three fish harbors, Kund Malir, ‎Sonmiani and Gadani, Baluchistan, Pakistan. The morphometric lengths (total length, ‎fork length, standard length, head length, pre-dorsal fin length, pre-orbital length, eye ‎diameter, lower-jaw length, pre-anal fin length, head depth, pectoral fin length, pelvic fin ‎length, greatest depth and pre-pelvic fin length and pre-pectoral fin length) were recorded ‎and the descriptive statistical parameters and correlation coefficient (r) were analysis ‎with independent variable (total length) and dependent variable (other morphometric ‎parameters). The result shows that morphometric parameters are highly correlated to ‎total length. Coefficient of correlation (r) indicated highest positive correlation between ‎total length and forked length (r = 0.961, r = 0.928 and r = 0.919 at Kund Malir, ‎Sonmiani and Gadani, respectively).The maximum total lengths of R. kanagurta ‎recorded in the present study were 26.1 cm at Kund Malir, 26.3 cm at Sonmiani and 29.0 ‎cm at Gadani. This study provides knowledge to the biologists regarding morphometric ‎characters of Indian mackerel, Rastrelliger kanagurta from the fish harbors of ‎Baluchistan to help in planning of conservation strategies for this fish species.‎
  • Comparative study of significant molluscans dwelling at two sites of Jiwani coast, ‎Pakistan.

    Ghani, Abdul; Afsar, Nuzhat; Ahmed, Riaz; Qadir, Shees; Saleh‎, Saifullah‎; Majeed‎, Samroz‎; Imam, Najeeb (2019-06-30)
    During the present study collectively eighty two (82) molluscan species have been ‎explored from Bandri (25 04. 788 N; 61 45. 059 E) and Shapk beach (25 01. 885 N; 61 ‎‎43. 682 E) of Jiwani coast. This study presents the first ever record of molluscan fauna ‎from shapk beach of Jiwani. Amongst these fifty eight (58) species were found belonging ‎to class gastropoda, twenty two (22) bivalves, one (1) scaphopod and one (1) ‎polyplachopora comprised of thirty nine (39) families. Each collected samples was ‎identified on species level as well as biometric data of certain species was calculated for ‎both sites. Molluscan species similarity was also calculated between two sites. For ‎gastropods it was remain 74 %, for bivalves 76 %, for Polyplacophora 100 % and for ‎Scapophoda 0 %. Meanwhile total similarity of molluscan species between two sites was ‎calculated 75 %. Notable identified species from Bandri and Shapak includes Oysters, ‎Muricids, Babylonia shells, Trochids, Turbinids and shells belonging to Pinnidae, Arcidae, ‎Veneridae families are of commercial significance which can be exploited for a variety ‎of purposes like edible, ornamental, therapeutic, dye extraction, and in cement industry ‎etc.‎
  • Comparison of metal uptake capacities of the brown algae Cystoseira barbata and ‎Cystoseira crinita (Phaeophyceae) collected in Sinop, Turkey.

    Arici, Elif; Bat‎, Levent; Yıldız, Gökhan (2019-06-30)
    Cystoseira barbata (Stackhouse) C. Agardh, 1820 and Cystoseira crinita Duby, ‎‎1830 widely distributed and dominant in the Black Sea collected from Sinop coastal ‎zone to monitor the current situation of regional metal pollution during the 2015-2016. ‎ Macro-algae, sediments and seawater samples were analyzed for metal contents (Al, ‎As, Cd, Co, Cu, Fe, Hg, Mn, Ni, Pb and Zn) using inductively coupled plasma mass ‎spectrometry (ICP-MS). The methodology was provided by using standard reference ‎material BCR 279 – Ulva lactuca.‎ The general metal uptake of Cystoseira spp. displayed a tendency in the order of ‎Hg2 and BCF>5000) that was a good ‎indicator for Cystoseira species. As a result of measured values, it is seen that Sinop ‎region is below the pollution level. The observed results of the elemental accumulation ‎noticed that Cystoseira spp. could be used regularly as a bio-monitor of coastal pollution ‎in the study area.‎
  • A new record of the parasitic copepod, Lernanthropus indicus (Pillai, 1967) ‎‎(Siphonostomatoida: Lernanthropidae) from Karachi coast Pakistan

    Farooq, Sumera; Batool, Atia; Ara, Mubeen; Arshad, Nazia (2019-06-30)
    A copepod parasite, Lernanthropus indicus (Pillai, 1967), was recorded first time from ‎the marine fish Otolithes ruber (Bloch & Schneider 1801) and Sphyraena putnamae ‎‎(Jordan & Seale 1905) captured from Karachi coast Pakistan. Lernanthropus indicus ‎‎(Pillai, 1967) is a rare species and was only reported from marine fishes of India, Iraq ‎and Egypt. This is the Fourth report on this species in the World and first report from ‎Pakistan.‎
  • Life-history traits of long whisker catfish Mystus gulio (Siluriformes: Bagridae) in the ‎coastal water (Maloncho river) of southern Bangladesh.

    Rahman‎, Obaidur; Hossain‎, Md. Yeamin; Islam‎, Md. Akhtarul; Rahman‎, Md. Ataur; Khatun‎, Dalia; Parvin‎, Most. Farida; Sarmin‎, Most. Shakila; Tanjin, Sumaya; Rahman, Md. Ashekur; Mawa, Zannatul; et al. (2020)
    This analysis illustrates the life history traits of Long whisker, Mystus gulio (Hamilton, ‎‎1822) including sex ratio, length-weight (LWRs) and length-length relationships (LLRs), ‎condition factors (KA, KF, KR), relative weight (WR) and form factor (a3.0), empirical based ‎size at first sexual maturity length (Lm) and natural mortality (MW, year-1). Total of 407 ‎individuals were scarcely collected from January-December 2017 using different fishing ‎gears. The sex ratio (M/F) was calculated as 1:1.26 (p<0.05). The overall sex ratio did not ‎differ significantly from the expected 1:1(p>0.05). The minimum-maximum total length ‎and body weight were observed as 5.20-15.50 cm and 2.11-33.60g for male, 5.20-17.50 ‎cm and 1.25-57.12g for female. All LWRs were very significant with all coefficients of ‎determination (r2)>0.967. The allometric coefficient indicated negative allometric growth ‎in male (b<3.0), positive allometric growth in female and also in combined (b>3.0). All ‎LLRs were significant with r2 values >0.965. The KF indicated the best condition of this ‎species for their well-being. The WR was not significantly diverse from 100 for males (p = ‎‎0.552) and females (p = 0.249), which indicate suitable condition for habitat. The a3.0 ‎were 0.0103 and 0.0108, and the Lm were 9.13 and 10.46 cm in total length for male and ‎female, respectively. Moreover, MW was 1.16 year-1 for male and 1.02 year-1 for female. ‎The results will be operative for the sustainable conservation of M. gulio in Bangladeshi ‎coastal waters and also nearby countries.‎
  • Some observations on the mass mortality of fish at Ormara (east bay), Balochistan in ‎October 2016‎.

    Moazzam, Muhammad (2020-12-31)
    Mass mortality of fish and shellfish species was recorded from Ormara (East Bay) in ‎October 2016. Initially a few dead fishes were observed to be floating in the open sea in ‎the East Bay area. With the passage of time, mass mortality was observed on the south-‎western part of the East Bay and heaps of fish were found floating in the area. This ‎event of mass mortality was only confined to the Oramara (East Bay) and not spread to ‎other parts of Oramara coast. In order to determine the dynamic of the fish mortality ‎and its spread in the area, sampling of the water of the area was collected on regular ‎intervals. It was observed that Noctiluca scintillans (Macartney) Kofoid & Swezy, 1921 ‎was present in extremely large numbers (highest recorded concentration 13 cells/ml) ‎which led to depletion of oxygen in the area resulting in mortality of large number of ‎fishes. In this fish kill demersal (bottom dwelling) as well as pelagic species (surface ‎dwelling) were found dead in the area in large numbers. Groupers (Epinephelus spp.), ‎Chinese pomfrets (Pampus chinensis), mullets, shrimp (Penaeus spp.) and crabs ‎‎(Portunus spp.) were dominated in the dead fishes and shellfishes. Oxygen depletion was ‎observed to confine to south-western part of the Ormara Bay where highest number of ‎dead fishes were observed. The phenomenon of mortality of fishes continued for 8 days ‎whereas normal condition started prevailing in 15 days and no mortality was observed ‎after 20 days since the start of the mortality phenomenon.‎
  • Cross-shelf phytoplankton dynamics in the northeastern Levantine ‎Basin.

    Uysal, Zahit (2020-12-31)
    A time series sampling program at monthly intervals was carried out at three stations ‎across the shelf in the northeastern Levantine basin to collect phytoplankton samples ‎and associated physical (temperature, salinity, secchi disc depth) variables over a year. ‎Quality and quantity of phytoplankton varied significantly across the shelf in time. Total ‎‎71 diatom, 40 dinoflagellate, 4 silicoflagellate and 17 coccolithophore species have been ‎identified from the study area. Diatoms’ contribution to total phytoplankton abundance ‎was maximal during autumn and spring in the nearshore and only during spring in the ‎mid shelf. Coccolithophores formed the dominant group almost throughout the year ‎except May and June in the offshore. Dinoflagellates formed the least abundant group in ‎the shelf over the year. Phytoplankton species have been found the most abundant and ‎diverse during spring when the river runoff to the basin was maximal. In general, a ‎decreasing trend in phytoplankton abundance towards offshore was prominent. ‎Phytoplankton has been found most abundant in the entire shelf during spring and early ‎summer reaching a peak level of 2.7 x 106 cells/l during May in the shallowest station. A ‎huge difference in quantity was observed in phytoplankton contents of the nearshore ‎and offshore waters during summer. Multivariate analyses have shown formation of ‎distinct seasonal phytoplankton assemblages throughout the year. Based on Spearman’s ‎rank correlation analysis, a highly significant negative correlation (n=35, rs= -.587, P < ‎‎0.01) was observed between phytoplankton abundance and surface salinity. ‎Superimposed surface temperatures seemed to better illustrate seasonal clusters relative ‎to surface salinity plots.‎
  • Heavy metal accumulation in sea cucumber ‎Actinopyga mauritiana (Echinodermata-‎‎Holothuroidea) from Cape Monze Beach Karachi, ‎Pakistan‎.

    Ahmed, Quratulan; Benzer, Semra; Ali, Qadeer Mohammad (2020-12-31)
    In the present study sea cucumber Actinopyga mauritiana, water and sediment samples ‎collected during September to December 2018. Six heavy metals (Fe, Cu, Mn, Zn, Pb, ‎and Cd) were analyzed in tissues (muscles, tentacles and guts), water and sediment by ‎atomic absorption spectrophotometer (AAS). The average measured levels of heavy ‎metals Fe, Cu, Mn, Zn, Pb and Cd in A. mauritiana muscle, tentacle and gut was 42.20 ± ‎‎9.47, 3.14 ± 0.48, 0.38 ± 0.22, 11.42 ± 4.34, 0.03 ± 0.00 and 0.02 ± 0.00; 36.90 ± 8.14, ‎‎3.22 ± 0.60, 0.40 ± 0.27, 10.50 ± 1.70, 0.04 ± 0.05 and 0.03 ± 0.02; 21.54 ± 5.06, 2.32 ± ‎‎0.66, 0.53 ± 0.16, 13.13 ± 2.90, 0.02 ± 0.02 and 0.02 ± 0.01 μg g−1 respectively. It is ‎useful to monitor all metal accumulation in the future.‎
  • First record of Leucothoe spinicarpus (Amphipoda: Leucothoidae) parasite within the ‎Aplysia (varria) cornigera from Pakistan.

    Ghory‎, Farhana S.; Ali, Qadeer Mohammad; Mubarak, Shumaila (2020-12-31)
    A parasitic species of Leucothoe spinicarpus (Abildgaard, 1789) occurred on the ‎ctenidium of Aplysia (Varria) cornigera Sowerby, 1869. The current study describes ‎taxonomic details of the parasitic species (Leucothoe spinicarpus). This is the first record ‎from Pakistan.‎
  • Ligula intestinalis (L., 1758) infection of ‎euryhaline fish the sand smelt Atherina ‎boyeri ‎Risso, 1810‎.

    Benzer, Semra (2020-06-30)
    Ligula intestinalis was found during the parasitological investigations of Atherina boyeri ‎specimens collected from Hirfanlı Reservoir, Turkey. It was found that 0.004% of all ‎individuals were infected by L. intestinalis including 2 female (0.0011% of all ‎individuals) and 5 male (0.0028% of all individuals). It was determined that the length ‎weight relationship equivalents of infected individuals with population differed from ‎those of non-infected individuals. The b value of the infected individuals was found to ‎be lower than the b value of the non-infected individuals. It is thought that the results ‎obtained in this study will be beneficial in preserving and improving the ecological ‎potential of the water system.‎
  • Heavy metal levels in elongate sole (Solea ‎elongata Day, 1877) from the Korangi ‎Fish ‎Harbour, Karachi, Pakistan.‎

    Yousuf‎, Farzana; Benzer‎, Semra; Ahmed, Quratulan (2020-06-30)
    In this study, fish samples collected from Elongate Sole (Solea elongata Day, 1877) ‎caught on the Korangi Fish Harbour in 2018 (South-west Monsoon and North-east ‎Monsoon) were analysed to determine concentrations of heavy metals: Fe, Zn, Cu, Pb, ‎Mn and Cd by an atomic absorption spectrophotometer, expressed per unit of dry weight ‎of each sample. The average measured level of Fe, Zn, Cu, Pb, Mn and Cd for Solea ‎elongata was 38.716±11.321 μg g−1, 16.638±3.344 μg g−1, 1.067±0.404 μg g−1, ‎‎0.022±0.043 μg g−1, 0.273±0.100 μg g−1 and 0.022±0.010 μg g−1, respectively. Although ‎the contamination values obtained from Solea elongata are below the limits, it is ‎important to follow the metal accumulation values.‎
  • Amino acid content in muscle tissue of the brown ‎meagre, Sciaena umbra Linnaeus, ‎‎1758 (Pisces: ‎Sciaenidae) as candidate species for aquaculture ‎in the Black Sea, ‎Turkey.

    Bilgin, Özlem; Maviş, Murat Emrah; Göksu-Gürsu, Gökçe (2020-06-30)
    In order to understand the nutritive quality focusing on amino acid profiles in the muscle ‎of the brown meagre, Sciaena umbra, and to evaluate the potential of the species as a ‎diet source for both human consumption and as candidate species for aquaculture, the ‎main amino acid components in the muscle of this species were analyzed. Amino acid ‎compositions were determined with the LC-MS/MS (Liquid Chromatography Tandem ‎Mass Spectrometer) instrument. Although a total of thirty-nine amino acids were ‎detected / searched by LC-MS/MS instrument, only twenty-four amino acid values were ‎determined. Seven of these amino acids are essential amino acids (EAAs), two are semi-‎essential amino acids (SEAAs) and fifteen are non-essential amino acids (NEAAs). The ‎most abundant amino acids in brown meagre meat were found as glutamic acid ‎‎(13.88%), lysine (10.43%), aspartic acid (9.62%), leucine (8.32%), and glycine (6.87%), ‎respectively. These five amino acids accounted for more than 49% of the total amount ‎of amino acids. The levels of the total amino acids (ΣAA = 24.17 g/100g), total essential ‎amino acids (ΣEAA = 9.42 g/100g), total non-essential amino acids (ΣNEAA = 12.39 ‎g/100g), total semi-essential amino acids (ΣSEAA = 2.36 g/100g) for brown meagre in the ‎Black Sea were higher than those reported in the other areas. This study shows that the ‎brown meagre has high nutritional qualities and the results are also presented as an ‎important criterion for obtaining information on amino acid nutritional requirements for ‎aquaculture and healthy human food source for dietitians.‎
  • A primary study on the bioaccumulation of ‎metals in Stereoderma kirschbergi (Heller, ‎‎1868) ‎from Sinop coasts of the southern Black Sea‎.

    Bat‎, Levent; Arici, Elif; Öztekin, Aysah; Şahin, Fatih (2020-06-30)
    The amounts of toxic metals (Pb, Hg and Cd) in tissues of Stereoderma kirschbergi in the ‎Sinop coasts of the south of the Black Sea were measured for the first time. Toxic metal ‎analyses were made by the Inductively Coupled Plasma - Mass Spectrometer. The ‎general tendency in all metal concentrations in both sediment and sea cucumber samples ‎were Pb>Hg>Cd. The results demonstrated that the toxic metal concentrations in ‎sediments were higher than organisms. Pb values in the sediment and sea cucumber were ‎higher than Hg and Cd. The bio-sediment accumulation factors for Cd, Hg and Pb were ‎lower than 1. S. kirschbergi is considered as a de-concentrator.‎
  • Preliminary studies on induced asexual ‎reproduction in Holothuria atra and Holothuria ‎pardalis under laboratory ‎conditions.

    Ahmed, Quratulan; Ali, Qadeer Mohammad (2020-06-30)
    Asexual reproduction was observed in H. atra and H. pardalis during 20th November ‎‎2019 to 20th February 2020. Asexual reproduction is a common phenomena in sea ‎cucumbers (class Holothuroidea) and organisms are capable of regenerating completely ‎or partially after fission and evisceration. The present research is a first attempt/trial on ‎induce asexual reproduction in H.atra and H. pardalis under the laboratory conditions in ‎Pakistan. The induced asexual reproduction is of high significance in aquaculture of ‎holothuria and could lead towards commercial production. During the last two decades ‎sea cucumber fishing showed a trend of overexploitation because they are easy to catch ‎besides high market demand. Many countries including Australia, Papua New Guinea, ‎Mauritius and Venezuela have imposed prohibition on sea cucumber fishing due to ‎depletion of population in wild. The findings from present research will be substantive ‎addition to the knowledge in the field of aquaculture and will be valuable to marine ‎scientist and aquaculturist in their future research.‎