An environmental life cycle assessment of forklift operation: a well-to-wheel analysis

Purpose

Among the many publications on the environmental life cycle assessment (LCA) of transport, there are only a few examples of works dedicated to means of internal transport. For this reason, it was decided to gather energy-oriented inventory data and to assess the environmental impact related to the operation of selected forklift trucks, as the most commonly used means of internal transport. This paper presents the main assumptions and the results in relation to the four phases of LCA: the goal and scope definition, the life cycle inventory, the life cycle impact assessment results, and the interpretation.

Methods

Ten forklifts with different engines were selected in order to carry out the life cycle assessment study. The research was based on the results of measuring the operating fuel consumption and exhaust gas emissions, conducted using the SEMTECH-DS mobile device from the PEMS group of devices. In order to make the measurements under a circumstance close to the real conditions of forklift exploitation, it was decided to slightly modify the operating cycle proposed in VDI 2198. The environmental impact of the fuel/electricity usage and exhaust gas emissions was assessed using the ISO 14040x guidelines and the IMPACT 2002+ method.

Results and discussion

The study showed that using an electric forklift to transport 1 t of payload over a distance of 1 km has a significantly smaller environmental impact than using one of the selected forklifts powered by an internal combustion engine. Using forklifts powered by liquefied petroleum gas (LPG) engines leads to a significantly higher environmental impact whilst the use of vehicles with diesel engines has an impact at a level several times lower. In a case of drives without load, where functional unit was defined as covering 1-km distance with no vehicle load, a lower impact for the electric vehicles was also obtained. The analysis includes the influences of the upstream processes of fuel and electrical energy production.

Conclusions

Even when Poland’s production scenario (based almost entirely on fossil fuels) is taken into consideration, the electric forklifts still show a clear advantage. It should be expected that, if the technological mix of electrical energy production for countries with a higher share of renewable or nuclear energy were to be taken into account, the environmental indicators for electric vehicles would be even lower. It is worth noting that only the energy aspects of forklift operation were analysed. Further studies aiming to collect inventory data relating to other exploitation aspects, as well as the production and utilization of the same vehicles, are planned as a continuation of this research.

     

Impact of the <Emphasis Type="Italic">PPAR gamma-2</Emphasis> gene polymorphisms on the metabolic state of postmenopausal women

The relationship Pro12Ala (rs1801282) and C1431T (rs3856806) polymorphisms of PPAR gamma-2 with glucose and lipid metabolism is not clear after menopause. We investigated the impact of the Pro12Ala and C1431T silent substitution in the 6th exon in PPAR gamma-2 gene on nutritional and metabolic status in 271 postmenopausal women (122 lean and 149 obese). The general linear model (GLM) approach to the two-way analysis of variance (ANOVA) was used to infer the interactions between the analysed genotypes. The frequency of the Pro-T haplotype was higher in obese than in lean women (p<0.0349). In the analysed GLM models according to obesity status, the C1431C genotype was related to a lower glucose concentration (β=?0.2103) in lean women, and to higher folliculotropic hormone FSH levels (β=0.1985) and lower waist circumferences (β=?0.1511) in obese women. The influence of C1431C was present regardless of the occurrence of the Pro12Ala polymorphism. The co-existence of the C1431C and Pro12Pro genotypes was related to lower values for triceps skinfold thickness compared those for the T1241/X and Ala12/X polymorphisms (β=?0.1425). The presence of C1431C decreased the differences between triceps values that were determined by Pro or Ala allele. In conclusion, C1431T polymorphism seems to have a more essential influence on anthropometric and biochemical parameters than is the case with Pro12Ala polymorphism.     

Does titanium in ionic form display a tissue-specific distribution?

Most studies have focused on the biodistribution of titanium(IV) oxide as nanoparticles or crystals in organism. But several reports suggested that titanium is released from implant in ionic form. Therefore, gaining insight into toxicokinetics of Ti ions will give valuable information, which may be useful when assessing the health risks of long-term exposure to titanium alloy implants in patients. A micro synchrotron radiation-induced X-ray fluorescence (µ-SRXRF) was utilized to investigate the titanium distribution in the liver, spleen and kidneys of rats following single intravenous or 30-days oral administration of metal (6 mg Ti/b.w.) in ionic form. Titanium was mainly retained in kidneys after both intravenous and oral dosing, and also its compartmentalization in this organ was observed. Titanium in the liver was non-uniformly distributed—metal accumulated in single aggregates, and some of them were also enriched in calcium. Correlation analysis showed that metal did not displace essential elements, and in liver titanium strongly correlated with calcium. Two-dimensional maps of Ti distribution show that the location of the element is characteristic for the route of administration and time of exposure. We demonstrated that µ-SRXRF can provide information on the distribution of titanium in internal structures of whole organs, which helps in enhancing our understanding of the mechanism of ionic titanium accumulation in the body. This is significant due to the popularity of titanium implants and the potential release of metal ions from them to the organism.     

Species differentiation in the genus Chara (Charophyceae): considerable phenotypic plasticity occurs within homogenous genetic groups

Charophytes are benthic algae with a complex morphology and high phenotypic plasticity. This has led to ambiguities in species delineation. However, until now genetic studies on Chara have been based on samples collected from a restricted geographic range or only included a restricted number of taxa. This may have hindered a general interpretation of the results. We applied barcoding of matK, a rapidly evolving coding section of the plastid genome, in 324 Chara samples collected from 19 countries, in order to test whether the distribution of barcode haplotypes among individuals was consistent with species boundaries as they are currently understood. The phylogenetic tree grouped the 324 Chara individuals, which according to commonly used identification keys represented 29 species, into 12 well-defined groups (i.e. monophyletic morphospecies or groups of morphospecies). Considerable morphological variation occurred within genetically homogeneous groups. This included traits which are commonly used for Chara species determination, such as the length and number of spine cells, the length of stipulodes and bract cells, cortication (tylacanthous, isostichous, aulacanthous and absent cortication), as well as sex differentiation. However, there were also substantial genetic differences among morphologically similar species (e.g. C. virgata – C. globularis – C. connivens). No morphological trait consistently reflected genetic differences. This indicates that morphological traits for specific taxa may serve as diagnostic tools for species delimitation, but that they are not generally suitable for inferring genetic differentiation or phylogenetic relationships. We propose that (i) C. virgata and C. strigosa, (ii) C. liljebladii, C. horrida and C. baltica, and (iii) C. hispida, C. rudis and C. polyacantha are conspecific. Our data also indicate that C. gymnophylla should be divided into tylacanthous forms (which are closely related to C. contraria) and aulacanthous forms (which are related to C. vulgaris).     

Arbuscular mycorrhiza and fungal root endophytes of weeds in an altitudinal gradient in the Pamir Alai Mountains of Central Asia

Arbuscular mycorrhiza and fungal root endophytes of three weeds, Galium tricornutum, Lycopsis orientalis and Scandix pecten-veneris, were studied in an altitudinal gradient of the Pamir Alai Mountains. Colonisation by arbuscular mycorrhizal fungi (AMF) was found in all species. Only in the case of G. tricornutum was there a rise in mycorrhizal parameters values found for the medium altitude range. Similar tendencies were observed in the case of the AMF colonisation potential assessment. This suggests that plant species' identity, dependency on symbiosis and interactions with soil properties determine root colonisation and the abundance of AMF in soils at the elevations in question. Four AMF species, Claroideoglomus claroideum, Funneliformis mosseae, Scutellospora dipurpurescens and Septoglomus constrictum, were isolated from trap cultures established on soil taken from under the weeds. Dark septate endophytes (DSE) accompanied the AMF in the roots of G. tricornutum and S. pecten-veneris; however, they were neither frequently occurring nor abundant. The sporangia of Olpidium spp. were observed with low frequency occurrence in G. tricornutum and S. pecten-veneris and more often in the roots of L. orientalis. However, in both cases, they were low in abundance. No differences were found for the presence of DSE and Olpidium in the altitudinal gradient.     

Mechanism of Delayed Increases in Kynurenine Pathway Metabolism in Damaged Brain Regions Following Transient Cerebral Ischemia

Abstract: Delayed increases in the levels of an endogenous N-methyl-D-aspartate receptor agonist, quinolinic acid (QUIN), have been demonstrated following transient ischemia in the gerbil and were postulated to be secondary to induction of indoleamine-2,3-dioxygenase (IDO) and other enzymes of the L-tryptophan-kynurenine pathway. In the present study, proportional increases in IDO activity and QUIN concentrations were found 4 days after 10 min of cerebral ischemia, with both responses in hippocampus > striatum > cerebral cortex > thalamus. These increases paralleled the severity of local brain injury and inflammation. IDO activity and QUIN concentrations were unchanged in the cerebellum of postischemic gerbils, which is consistent with the preservation of blood flow and resultant absence of pathology in this region. Blood QUIN and L-kynurenine concentrations were not affected by ischemia. Brain tissue QUIN levels at 4 days postischemia exceeded blood concentrations, minimizing a role for breakdown of the blood–brain barrier. Marked increases in the activity of kynureninase, kynurenine 3-hydroxylase, and 3-hydroxyanthranilate-3,4-dioxygenase were also detected in hippocampus but not in cerebellum on day 4 of recirculation. In vivo synthesis of [¹³C₆]QUIN was demonstrated, using mass spectrometry, in hippocampus but not in cerebellum of 4-day postischemic animals 1 h after intracisternal administration of L-[¹³C₆]tryptophan. However, accumulation of QUIN was demonstrated in both cerebellum and hippocampus of control gerbils following an intracisternal injection of 3-hydroxyanthranilic acid, which verifies the availability of precursor to both regions when administered intracisternally. Notably, although IDO activity and QUIN concentrations were unchanged in the cerebellum of ischemic gerbils, both IDO activity and QUIN content were increased in cerebellum to approximately the same degree as in hippocampus, striatum, cerebral cortex, and thalamus 24 h after immune stimulation by systemic pokeweed mitogen administration, demonstrating that the cerebellum can increase IDO activity and QUIN content in response to immune activation. No changes in kynurenic acid concentrations in either hippocampus, cerebellum, or cerebrospinal fluid were observed in the postischemic gerbils compared with controls, in accordance with the unaffected activity of kynurenine aminotransferase activity. Collectively, these results support roles for IDO, kynureninase, kynurenine 3-hydroxylase, and 3-hydroxyanthranilate-3,4-dioxygenase in accelerating the conversion of L-tryptophan and other substrates to QUIN in damaged brain regions following transient cerebral ischemia. Immunocytochemical results demonstrated the presence of macrophage infiltrates in hippocampus and other brain regions that parallel the extent of these biochemical changes. We hypothesize that increased kynurenine pathway metabolism after ischemia reflects the presence of macrophages and other reactive cell populations at sites of brain injury.     

Kynurenine Pathway Enzymes in Brain: Responses to Ischemic Brain Injury Versus Systemic Immune Activation

Accumulation of l -kynurenine and quinolinic acid (QUIN) in the brain occurs after either ischemic brain injury or after systemic administration of pokeweed mitogen. Although conversion of l -[¹³C₆]tryptophan to [¹³C₆]-QUIN has not been demonstrated in brain either from normal gerbils or from gerbils given pokeweed mitogen, direct conversion in brain tissue does occur 4 days after transient cerebral ischemia. Increased activities of enzymes distal to indoleamine-2,3-dioxygenase may determine whether l -kynurenine is converted to QUIN. One day after 10 min of cerebral ischemia, the activities of kynureninase and 3-hydroxy-3,4-dioxygenase were increased in the hippocampus, but local QUIN levels and the activities of the indoleamine-2,3-dioxygenase and kynurenine-3-hydroxylase were unchanged. By days 2 and 4 after ischemia, however, the activities of all of these enzymes in the hippocampus as well as QUIN levels were significantly increased. Kynurenine aminotransferase activity in the hippocampus was unchanged on days 1 and 2 after ischemia but was decreased on day 4, at a time when local kynurenic acid levels were unchanged. A putative precursor of QUIN, [¹³C₆]anthranilic acid, was not converted to [¹³C₆]-QUIN in the hippocampus of either normal or 4-day postischemic gerbils. Gerbil macrophages stimulated by endo-toxin in vitro converted l -[¹³C₆]tryptophan to [¹³C_e]QUIN. Kinetic analysis of kynurenine-3-hydroxylase activity in the cerebral cortex of postischemic gerbils showed that V_max increased, without changes in K_m. Systemic administration of pokeweed mitogen increased indoleamine-2,3-dioxygenase and kynureninase activities in the brain without significant changes in kynurenine-3-hydroxylase or 3-hydroxyanthranilate-3,4-dioxygenase activities. Increases in kynurenine-3-hydroxylase activity, in conjunction with induction of indoleamine-2,3-dioxygenase, kynureninase, and 3-hydroxyanthranilate-3,4-dioxygenase in macro-phage infiltrates at the site of brain injury, may explain the ability of postischemic hippocampus to convert l -[¹³C₆]tryptophan to [¹³C₆]QUIN.