64 research outputs found
Intermodal freight transport logistics : applications for improving port performance in Nigeria
Plan de desarrollo turístico sustentable de la parroquia Ávila Huiruno, del cantón Loreto, provincia de Orellana, correspondiente al periodo 2019-2021
El presente Trabajo de Titulación tuvo por objetivo elaborar un Plan de Desarrollo Turístico Sustentable de la Parroquia rural Ávila Huiruno del Cantón Loreto Provincia de Orellana, que permita el impulso económico, social, ambiental y cultural de manera sustentable de todas las comunidades de la parroquia. La perspectiva a corto, mediano o largo plazo, es la respuesta a la pregunta de ¿En dónde necesita estar la organización en un momento específico del futuro para desempeñar su Visión, Misión y Estrategias? El Planeamiento es un proceso dinámico lo suficientemente flexible para permitir y hasta forzar modificaciones en los planes, a fin de responder a las cambiantes circunstancias. Desde el punto de vista del turismo comunitario el planeamiento estratégico es importante porque se sustenta en la visión que tiene el país en consolidar un turismo sostenible como una herramienta eficaz para el desarrollo integral y con rentabilidad social que genera oportunidades de empleo y de mejoramiento de la calidad de vida de la población. Los planes que se emplearon fueron de un nivel descriptivo que buscó especificar las propiedades importantes del grupo objeto de estudio. Se midieron las variables independientemente con el fin de comprobar la hipótesis planteada. El método utilizado fue el inductivo y deductivo para observar las causas y efectos del problema y llegar a una conclusión. Las técnicas empleadas estuvieron dirigidas a los prestadores de servicios y a los turistas, evidenciándose la importancia de la planificación estratégica del turismo comunitario para las comunidades de la Parroquia Ávila Huiruno, mediante un proceso sistemático para gestionar la evolución de la actividad hacia el turismo sostenible y un futuro comunitario comprometido con los participantes de la empresa comunitaria y con la demanda al brindar un servicio de calidad. El Plan de Desarrollo es posible mediante la autogestión como instrumento de desarrollo de carácter autónomo, integral en todos los niveles y global considerando a todos los participantes.The objective of this study was to develop a sustainable tourism development plan for the A vila Huimno niral parish located in Loreto province of Orellana, which allows thc sustainable economic, social, environmental and cultural impulse of all the communities of the parish. The short, medium or long term perspective is the answer the follwing question:Where does the organization need to be at a specific moment in the future to fulfill its vision, mission and strategies? Planning is a d ynainic process fleKible cnough to allow and even force modifications to plans in response to changing circumstances. From the point of view of‘ community tourism, strategic planning is important because it is based on the vision that thc country has in consolidating sustainable tourism as an effective tool for comprehensive development and with social profitability that generates employment opportunities and improvement of the coinnuntty. quality of life of the population. The plans that were used were of a descriptive levcl that sought to specify the important properties of the group under study. The variables were measured independently in order to verify the proposed hypothesis. The method used was inductive and deductive to observe the causes and effects of the problem and reach a conclusion. The techniques used were aimed at service providers and toutlsts, evidencing the importance of strategic planning of community tourism for the communities of the hvila Huiiuno parish, through a systematic pfocess to manage the evolution of the activity towards sustainable tourism and a community future committed to the participants of the cominunlty business and to the demand by providing a quality service. The devclopinent plan is possible through self-managcineiit as an autonomous development instrument, comprehensive at all levels and global considering all participants
UNCONFINED COMPRESSIVE STRENGTH OF CEMENT STABILIZED PEAT WITH RUBBER CHIPS AND SAND FILLER MIXED AT VARIOUS WATER TO ADDITIVE RATIO
Peat is known to be a very problematic soil as it has high natural moisture content, high compressibility and low shear strength, high degree of spatial variability
and high permeability which requires special cnsiderations for construction over them. In Malaysia, peat soils cover 2,457,730 ha (7.45%) of Malaysia’s total land area which is 32,975,800 ha. Due to the geotechnical problems of peat soil, previous researchers have found several methods to improve the behaviour of peat soil by
using chemical stabilization method. In this study, peat samples were collected from Kampung Meranek, Kota Samarahan, Sarawak and was classified under H8 (Sapric
Peat) according to Von Post Humification scale. The samples were mixed at its natural moisture content with the addition of cement, constant percentage of rubber
chips and constant percentage of siliceous sand. A suitable mixing water- additive ratio of 2.0, 2.5 and 3.0 had been chosen to determine the optimum strength of peat
soil and the samples were cured at a curing period of 7, 14 and 28 days respectively. After those curing periods, the compressive strength of samples were obtained by
conducting unconfined compressive strength (UCS) test in the laboratory. The results of strength gained that had been obtained from this study indicated that wateradditive ratio of 2.0 is the optimum ratio as it achieved the highest maximum strength at curing period of 28 days. This study had proven that the compressive strength of peat increases with the inclusion of cement, rubber chips and sand at a specific wateradditive
ratio through curing period
Water Quality of Batang Lupar Estuary, Sarawak
This study was conducted to determine the water quality status in Batang Lupar estuary of Sarawak. A sampling
was carried out at Batang Lupar estuary on 17
th December 2012. A total of six sampling stations with 2 km
distance between two adjacent stations was chosen. Both in-situ and ex-situ physico-chemical parameters of
water were measured and analysed. This included depth (7.40 ± 0.00 m to 10.50 ± 0.00 m), water temperature
(29.9 ± 0.05 °C to 31.4 ± 4.35 °C), pH (7.35 ± 0.00 to pH 7.44 ± 0.00), DO (6.29 ± 0.08 mg/L to 8.16 ± 0.23
mg/L), salinity (11.5 ± 0.00 PSU to 18.7 ± 0.00 PSU), conductivity (19.60 ± 0.02 µS to 28.26 ± 0.01 µS),
turbidity (87 ± 7.76 FTU to 992 ± 13.85 FTU), water transparency (11 ± 0.00 mm to 24 ± 0.00 mm), chlorophylla
(0.4418 ± 0.00 µg/L to 3.4403 ± 0.30 µg/L), TSS (1358.0 ± 20.29 mg/L to 19348.6 ± 1746.89 mg/L), BOD5
(1.63 ± 0.12 mg/L to 3.63 ± 0.28 mg/L), Nitrite (0.009 ± 0.00 mg/L to 0.012 ± 0.00 mg/L), Nitrate (0.02 ± 0.00
mg/L to 0.06 ± 0.02 mg/L), Ammonia-Nitrogen (0.32 ± 0.24 mg/L to 2.04 ± 0.12 mg/L), and Orthophosphate
(0.03 ± 0.01 mg/L to 0.10 ± 0.09 mg/L). Other than that, heavy metals were analyzed too including As (0.1420 ±
0.09 mg/L to 0.1808 ± 0.03 mg/L), Cu (0.0073 ± 0.00 mg/L to 0.0110 ± 0.00 mg/L), Pb (undetected), Mn (0.0098
± 0.00 mg/L to 1.1769 ± 0.48 mg/L), Ni (0.0054 ± 0.00 mg/L to 0.0162 ± 0.00 mg/L) and Zn (0.0063 ± 0.00
mg/L to 0.1228 ± 0.04 mg/L). Nitrite, Nitrate, Zn and DO were within the standard range proposed by MWQS of
DOE. The water quality of Batang Lupar Estuary was clean and safe. Human residential along the river and other
activities such as logging and agriculture are amongst the factor influencing the water quality of Batang Lupar
Estuary
Corrigendum: Molecular analysis of the UV-inducible pili operon from Sulfolobus acidocaldarius (vol 2, pg 928, 2013)
Correction regarding Sulfolobus acidocaldarius strain GA06 Upon resequencing we discovered that strain GA06 was not, as published (van Wolferen et al., 2013), a deletion of the upsX ORF and a 40 bp upstream region, but was a deletion starting 55 bp upstream and ending 35 bp downstream of upsX. Since this could affect the genes downstream of UpsX, a clean deletion mutant of the upsX promoter (all 261 bp upstream of upsX) was created and analysed by qRT-PCR studies as well as by UV-induced aggregation assays. qRT-PCR experiments showed that in this strain, upsE, F, A and B were upregulated normally upon UV-induction, and aggregation experiments showed that the deletion mutant of the upsX promoter aggregated in a similar manner as the WT strain after treatment with UV-light. These results are similar to the results obtained for the deletion of the upsX gene (MW115, ΔupsX, Figures 4 and 5). Therefore, the promoter in front of upsX is not the primary promoter of the ups-operon and is also not essential for transcription of the other ups-genes. Additionally, we discovered that the EM image in Figure 6 (GA06) was accidently replaced by an image of strain (ΔupsEF). Both strains did not show any UV induced pili, but the specific image shown was not obtained for this strain. All other strains and EM pictures and the conclusions obtained with these strains are correct
Dissolved inorganic nitrogen in a tropical estuary in Malaysia : transport and transformation
Dissolved inorganic nitrogen (DIN), including nitrate, nitrite and ammonium, frequently acts as the limitation
for primary productivity. Our study focused on the transport and transformation of DIN in a tropical estuary, i.e., the Rajang River estuary, in Borneo, Malaysia. Three cruises were conducted in August 2016 and February–March and September 2017, covering both dry and wet seasons. Before entering the coastal delta, decomposition of the terrestrial organic matter and the subsequent soil leaching was assumed to be the main source of DIN in the river water. In the estuary, decomposition of dissolved organic nitrogen was an
additional DIN source, which markedly increased DIN concentrations in August 2016 (dry season). In the wet season (February 2017), ammonium concentrations showed a relatively conservative distribution during the mixing, and the nitrate addition was weak. La Niña events induced high precipitations and discharge rates, decreased reaction intensities of ammonification and nitrification. Hence similar distribution patterns of DIN species in the estuary were found in September 2017 (end of the dry season). The magnitude of riverine DIN flux varied between 77.2 and 101.5 t N d−1 , which might be an important support for the coastal primary productivity
Distribution and flux of dissolved iron in the peatland-draining rivers and estuaries of Sarawak, Malaysian Borneo
Dissolved iron (dFe) is essential for multiple biogeochemical reactions in oceans, such as photosynthesis, respiration and nitrogen fixation. Currently, large uncertainties remain regarding the input of riverine dFe into coastal oceans, especially in tropical rivers in southeastern Asia. In the present study, the concentrations of dFe and distribution patterns of dFe were determined along the salinity gradient in the Rajang River and three blackwater rivers that drain from peatlands, including the Maludam River, the Sebuyau River and the Simunjan River. In the Rajang River, the dFe concentration in freshwater samples (salinity < 1 PSU – practical salinity units) in the wet season (March 2017) was higher than that in the dry season (August 2016), which might be related to the resuspension of sediment particles and soil erosion from cropland. In the Rajang estuary, an intense removal of dFe in low-salinity waters (salinity < 15 PSU) was observed, which was likely due to salt-induced flocculation and absorption of dFe onto suspended particulate matter (SPM). However, increases in the dFe concentration in the wet season were also found, which may be related to dFe desorption from SPM and the influences of agricultural activities. In the blackwater rivers, the dFe concentration reached 44.2 µmol L−1
, indicating a strong contribution to the dFe budget from peatland leaching. The dFe flux derived from the Rajang estuary to the South China Sea was estimated to
be 6.4±2.3×105 kg yr−1 . For blackwater rivers, the dFe flux was approximately 1.1 ± 0.5 × 105 kg yr−1 in the Maludam River. Anthropogenic activities may play an important role in the dFe yield, such as in the Serendeng tributary of the Rajang River and Simunjan River, where intensive oil palm plantations were observed
Distribution and behaviour of dissolved selenium in tropical peatland-draining rivers and estuaries of Malaysia
Selenium (Se) is an essential micronutrient for
aquatic organisms. Despite its importance, our current
knowledge of the biogeochemical cycling of dissolved Se in tropical estuaries is limited, especially in Southeast Asia. To gain insights into Se cycling in tropical peat-draining rivers and estuaries, samples were collected from the Rajang, Maludam, Sebuyau, Simunjan, Sematan, Samunsam and Lunda rivers and estuaries in western Sarawak, Malaysia, in March and September 2017 and analysed for various forms of Se (dissolved inorganic and organic). Mean total dissolved Se (TDSe), dissolved inorganic Se (DISe) and dissolved organic Se concentrations (DOSe) were 2.2 nmol L−1 (range: 0.7 to
5.7 nmol L−1 ), 0.18 nmol L−1 (range: less than the detection limit to 0.47 nmol L−1 ) and 2.0 nmol L−1
(range: 0.42 to 5.7 nmol L−1 ), respectively. In acidic, low-oxygen, organicrich blackwater (peatland-draining) rivers, the concentrations of DISe were extremely low (near or below the detection limit, i.e. 0.0063 nmol L−1
), whereas those of DOSe were high. In rivers and estuaries that drained peatland, DOSe / TDSe ratios ranged from 0.67 to 0.99, showing that DOSe dominated. The positive relationship between DISe and salinity and the negative relationship between DOSe and salinity indicate marine and terrestrial origins of DISe and
DOSe, respectively. The positive correlations of DOSe with the humification index and humic-like chromophoric dissolved organic matter components in freshwater river reaches suggest that peat soils are probably the main source of DOSe The DOSe fractions may be associated with high molecular weight peatland-derived aromatic and black carbon compounds and may photodegrade to more bioavailable forms once transported to coastal waters. The TDSe flux delivered by the peat-draining rivers exceeded those reported for other small rivers and is quantitatively more significant than previously thought
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