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Xjenza Online Vol. 4 Iss. 1 - July 2016
Xjenza Online Vol. 4 Iss. 1 - July 2016 ISSUE: Xjenza Online Vol. 4 Iss. 1 - July 2016



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Article
20th Anniversary of Xjenza (July 1996 - July 2016), the offcial Journal of the Malta Chamber of Scientists
Angela A. Xuereb Anastasi, Giuseppe Di Giovanni
Pages: 1 - 3
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Article
Escalation of Fireworks in Malta: Environmental Forensic Evidence from Perchlorate in Dust Fall
Colette Pace, Alfred J. Vella
Pages: 4 - 10
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Abstract:
Summer in Malta is accompanied by reworks as part of the numerous (about 85) religious festivals (festa) that occur throughout the period. We attempted to establish whether rework activity is truly following ocial trade statistics, which imply a decreasing trend, or otherwise. Firework manufacture critically depends on the availability of oxidising agents, two of which (KNO3, KClO3) being controlled by permits but not potassium perchlorate (KClO4) which is freely available. Recent changes in legislation have slightly decreased the quantity of KClO3 and increased that of KNO3 and according to ocial trade statistics, consumption of KClO4 has decreased from 17 t=a in 2010 to  2:5 t=a during 2011{2014. However, from levels of perchlorate in dust fall and rate of total deposition we calculated the quantity of KClO4 used during 2012 and obtained  90 t=a, 36 times the ocial gure. This situation is serious since the danger of accidental explosion during manufacture escalates as production intensi es. Also, contamination of the environment by rework-waste appears destined to remain high with possible consequent effects on human health.

Doi: 10.7423/XJENZA.2016.1.01
Article
The re-emergence of the B1 cell compartment: Is this a pre-lymphoma stage?
Norman Formosa, Christian Saliba, Shawn Baldacchino, David J. Camilleri, Godfrey Grech
Pages: 11 - 17
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Abstract:
Chronic Lymphocytic Leukemia (CLL) are in some cases stereotyped for immunoglobulin variants in different populations, suggesting emergence of B cell subsets following presentation of the same antigen. CLL cells may originate from CD5+ nave cells and from CD5 memory cells. Gene expression studies characterized a common cell of origin of the two clinical categories of CLL; the unmutated aggressive type and the mutated indolent type. The aim of this study was to investigate the presence of CD5 positive B cells in the elderly and their potential stimulation with exosomes derived from tumor cells. The ndings from this study is aimed to create a model to identify instigating carcinomatous factors that may stimulate B1 cells to transform into a CLL-like model. In this study we show that CD19+ cells (B cells) in cord blood have a high expression of CD5. CD19/CD5 staining of blood samples from senior citizens showed the presence of B cells which also express the CD5 marker, though at a lower expression when compared to CLL cells (CD19+/CD5dim B cells). Measurement of clonality using «/ ow cytometry staining show a monoclonal origin of the human CD19+/CD5dimB cells. Monoclonal B cell Lymphocytosis in the elderly is a potential cell compartment that represents the origin of B cell proliferative disorders. The origin of the B cell proliferative disease requires antigen stimulation. A preliminary experiment showed that sorted lymphocytes can be stimulated by exosomes isolated from 2 cancer cells lines, A549 (lung epithelial) and PC3 (prostate cell line). In comparison with phytohaemagglutinin (PHA) and phorbolmyristate acetate (PMA), known lymphocyte stimulators, the exosomes stimulated the proliferation of monocytic-like cells. Further characterization is required to know the origin of these cells. The result shows that one can speculate that exosomes present cancer-derived antigens and stimulate cell proliferation. Further studies are required to evaluate the potential transformation capacity of cancer-derived exosomes. In addition, various cytokines were measured in the sera of senior citizens to investigate a differential release of cytokines in the presence or absence of the CD19+/CD5dim B cells. Cytokines examined were not signi cantly different between the 2 groups and further evaluation of cytokine levels is required.

Doi: 10.7423/XJENZA.2016.1.02
Article
Influence of Antimony on Structure and Physical Properties of Molten Tin
Andriy Yakymovych, Stepan Mudry, Yuriy Plevachuk, Vasil Sklyarchuk, Valeri Sidorov
Pages: 18 - 21
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Abstract:
Structure of liquid Sb-Sn alloys were stud- ied by means of viscosity measurements and X-ray dif- fraction. Structural factors and pair correlation func- tions were analysed and interpreted using the random atomic distribution model. The features of temperat- ure dependence of the viscosity coefficient were analysed taking into account X-ray di raction patterns. The res- ults allow us to conclude that Sb atoms substitute for Sn atoms, forming a typical atomic solution, which reveals chemical and topological short-range order. Moreover, certain atoms form Sb- and Sn-based SbnSnm associates and self-associates.

Doi: 10.7423/XJENZA.2016.1.03
Article
Numerical Modelling and Economics of Agricultural Land Degradation in the Maltese Islands
Daniel Sultana
Pages: 22 - 34
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Abstract:
The study applies a new GIS-based numerical modelling approach to calculate the economic burden agricultural land owners su er through soil erosion land degradation. Numerically modelled soil erosion volumes in Maltese agricultural areas were estimated at 766 278m3=yr costing 7:98Me=yr to replace. The model calculates that the average owner incurs 1170e=0:01km2=yr on soil replacement and soil improvement requirements. With average yearly economic revenue of 1720e=0:01km2=yr, this cost bene t imbalance may force agricultural land owners to not replace eroded soils. Over time, as a result of soil erosion, an increasingly large proportion of agricultural land may no longer suitable for agricultural purposes. Over 50 years, 1:53km2 (0.5% of Maltese area) of agricultural land may be depleted of soil, incurring an average national agricultural revenue loss of 0:26Me per year. Soil erosion rates, and associated economic implications, may be mitigated with cost effective management practices. Two such practices include conservation tillage, which o ers various economic advantages to farmers, and the restoration of breaches in slope-facing rubble walls in areas subject to soil erosion. The latter may require an investment of 11:94Me at the National scale or e1,600 by the average agricultural land owner. Both measures contribute towards the sustainable use of Maltese agricultural areas and maintaining key associated ecosystems services.

Doi: 10.7423/XJENZA.2016.1.04
Article
Economic and Labour Market Implications of Global Environmental Change on Agriculture and Viticulture in Malta
Anthony Meli
Pages: 35 - 40
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Abstract:
Agriculture contributes but a limited amount to Europe's gross domestic production, and the overall weakness of the European economy to climatic changes on agriculture is deemed low. Agriculture remains more considerable in the southern and southeastern European states with regards to employment and economic contribution and these regions are expected to face decreases in yields of 10% or more as a result of the reduction of the growing season and decreased rainfall. In Malta, other than cereal production as a fodder crop, most other crops are supported with a degree of irrigation that may ultimately mitigate adverse climatic conditions. Local producers have indicated that cereals, olives and vines have so far demonstrated varying degrees of susceptibility to climatic factors, although, arguably management factors are also relevant. The development of drier and warmer conditions in the Mediterranean region would also create conditions that are favourable to pests. Analysis of potential output effects triggered by global environmental change indicates that some 6,300 hectares on which wheat, olives and vines are grown, or 55% of Malta's total utilisable agricultural area, could in effect be rendered economically unsustainable when productivity falls by about 23%. Such heavy losses could constitute a potential risk to the sustainability of rural farming systems and livelihoods in Malta.

Doi: 10.7423/XJENZA.2016.1.05
Article
Geology and wines of Pachino - Portopalo area. Preliminary outlines
Pietro Carveni, Patrizia Sibi, Alessandro Torre, Fabio Torre, Mario Valletta
Pages: 41 - 43
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Abstract:
This research, still in a developmental phase, analyses geological peculiarities and the relation- ships between them and the vineyards typical to the Pachino-Portopalo area. The actual knowledge does not yet allow the draw- ing of tourist routes from which a geo-tourist would be able to join together Geosites and Oenosites. This will be one of the main topics of future research, oriented to produce substantial contributions to the sustainable development of this area.

Doi: 10.7423/XJENZA.2016.1.06
Article
Dativizable or Non-dativizable: That is the question? A syntactic- semantic analysis of English (non)-dativizable constructions in the production of a set of 2L1 English/Spanish simultaneous bilingual twins
Silvia Sánchez Calderón, Raquel Fernández Fuertes
Pages: 44 - 57
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Abstract:
This paper analyzes the syntactico-semantic factors which trigger Dative shift in English dativizable verbs, i.e. those verbs that allow alternation between double object and prepositional complement constructions. It also focuses on non-dativizable verbs that restrict their subcategorization framework to either double object or prepositional complement constructions. This syntactico-semantic relation between dativizable and nondativizable structures is addressed in acquisition by examining the incidence for the two verb types in a set of English/Spanish 2L1 bilingual twins. Our results show that the syntactic and semantic features that dativizable and non-dativizables present go hand in hand with the age of rst occurrence and the language development of the participants. Hence, dativizable to-dative double object constructions (DOC) are the utterances produced the earliest at the age of 2, as opposed to dativizable to/for-datives and non-dativizable constructions, which begin to emerge at around the age of 3. Finally, our results also suggest that the high adult input frequency explains the twins' early production of dativizable structures and that, in the same way, the children's low exposure to non-dativizable utterances correlates with the later occurrence in the twins' spontaneous production.

Doi: 10.7423/XJENZA.2016.1.07
Article
CM1106 STEMCHEM: Chemical Approaches to Targeting Drug Resistance Cancer Stem Cells
Pierre Schembri-Wismayer, Analisse Cassar, Krystle Blaire Theuma, Iona Stipourou, Daniele Passarella, Sherif Suleiman, Neville Micallef
Pages: 58 - 63
Abstract | View full article | PDF
Abstract:
STEMCHEM is a COST action aiming to target causes of drug resistance in cancer stem cells. Cancer stem cells are cells which are believed to be re- sponsible for the larger part of the regenerative capacity of cancers. They are also thought to be similar to adult stem cells in that they do not proliferate most of the time and are thus resistant to many kinds of chemotherapy. The action brings together labs around Europe in both biological and chemical elds to work together in this regard. Biologists targeting individual stem-cell related molecules as well as stem cell phenotypes (like the un- differentiated state), test chemicals from numerous labs for activity in high throughput screens, with the aim of identifying new drug targets. This COST action, like most others, o ers opportunities for Malta, both in a general way and also particularly for a small country with small labs.

Doi: 10.7423/XJENZA.2016.1.08
Article
Supramolecular Chemistry in Water: Self-Assembly of Multi- Component Fluorescent Molecular Logic Gates in Micelles
David C. Magri, Paola F. da Costa, Kyle A. Paterson
Pages: 64 - 71
Abstract | View full article | PDF
Abstract:
A recent strategy for developing supramolecular logic gates in water is based on combinations of molecules via self-assembly with surfactants, which eliminates the need for time-consuming synthesis. The self-assembly of surfactants and lumophores and receptors can result in interesting properties providing cooperative effects useful for molecular information processing and other potential applications such as drug delivery systems. This article highlights some of the recent advancements in supramolecular information processing using microheterogeneous media including micelles in aqueous solution.

Doi: 10.7423/XJENZA.2016.1.09
Article
Accessibility as an indicator of transport equity. The case of public transport infrastructure in Malta, and its impact on the elderly
Thérèse Bajada, Deborah Mifsud, Floridea Di Ciommo
Pages: 72 - 81
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Abstract:
The concept of equity is essential in transport because inequities lead to the formation of transport-disadvantaged groups, such as the elderly, disabled and low-income people. This paper focuses on the elderly. Due to age-related circumstances, several elderly persons have to surrender on driving, consequently they become highly dependent on public transport. Hence, accessible public transport is crucial to provide them with the necessary mobility. This research considers accessibility as a key indicator for transport equity, since the latter primarily deals with the provision of equal access to opportunities. The study focuses on the case of Malta's public transport system, which is composed of the bus service. The uniqueness of the Maltese case is that transport policy is fragmented, and is not focused on equity. This paper looks at three aspects of accessibility related to road infrastructure, public transport infrastructure, and the bus eet. The rst aspect refers to accessibility at the macro scale, for instance, pavements may not be solely designed to cater for the bus service, but they are an integrative part of it. The meso scale refers to accessibility of infrastructure in physical and cyber form, such as access to and on bus stops and access to online travel information. The bus eet refers to the micro scale of accessibility, which may include boarding and alighting the vehicle, and access on the vehicle. The research approach involves a review of existing Maltese public transport policy, with speci c focus on whether accessibility for the elderly is considered in the context of the afore-mentioned scales. It is envisaged that the minimal or non-existent policy on accessibility in public transport that focuses on elderly, makes this population segment at a double disadvantage. The research concludes with implications for policy related to public transport accessibility in a Maltese ageing society.

Doi: 10.7423/XJENZA.2016.1.10
Article
Reviewing the review process: New Frontiers of Peer Review
Ramani Wijesinha-Bettoni, Kalpana Shankar, Ana Marusic, Francisco Grimaldo, Marco Seeber, Bruce Edmonds, Chiara Franzoni, Flaminio Squazzoni
Pages: 82 - 85
Abstract | View full article | PDF
Abstract:
This news article introduces a new COST Action entitled PEERE (TD1306), which stands for New Frontiers of Peer Review (PEERE). PEERE is a trans-domain proposal which brings together research- ers from various different disciplines and science stake- holders for the purpose of reviewing the process of peer review. PEERE ocially began in May 2014 and will end in May 2018. Thirty-one countries, including Malta, are currently participating in the Action. In order to set the context in which this COST Action was initiated, we rst look very brie y at the history of the process of peer review and various models of peer review currently in use. We then share what this COST Action hopes to achieve.

Doi: 10.7423/XJENZA.2016.1.11
Article
A culture collection of Maltese microorganisms for application in biotechnology, biomedicine and industry
Gabrielle Zammit
Pages: 86 - 89
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Article
The fi rst Malta Brain Awareness Week: An Interview with the Coordinator of the Malta Neuroscience Network
Giuseppe Di Giovanni
Pages: 90 - 96
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