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2021 ◽  
Vol 2 ◽  
Author(s):  
Guillaume Ghisbain

The unsustainable use of ecosystems by human societies has put global biodiversity in peril. Bees are, in this context, a popular example of a highly diversified group of pollinators whose collapse is a major concern given the invaluable ecosystem services they provide. Amongst them, bumblebees (Bombus) have increasingly drawn the attention of scientists due to their dramatic population declines globally. This regression has converted them into popular conservation entities, making them the second most studied group of bees worldwide. However, in addition to have become relevant models in the fields of ecology, evolution and biogeography, bumblebees have also been used as models for studying wild bee decline and conservation worldwide. Integrating evidence from the comparative ecology and resilience of bumblebees and wild bees, I discuss the relevance of using Bombus as radars for wild bee decline worldwide. Responses of bumblebees to environmental changes are generally not comparable with those of wild bees because of their relatively long activity period, their inherent sensitivity to high temperatures, their relatively generalist diet breadth and many aspects arising from their eusocial behavior. Moreover, important differences in the available historical data between bumblebees and other bees make comparisons of conservation status even more arduous. Overall, these results reinforce the need for conservation actions that consider a higher level of understanding of ecological diversity in wild bees, highlight the need for an updated and more extensive sampling of these organisms, and emphasize that more caution is required when extrapolating trends from model species.


2021 ◽  
Author(s):  
◽  
Patty Ramírez

<p>Amphibian populations are in general decline internationally. The current situation of amphibian populations highlights the urgent need for comprehensive information on species’ ecology to better assess conservation and management strategies. Movement behaviour and microhabitat selection give insights into how amphibians use the environment and interact with their surroundings, and are essential to establishing their sensitivity to the global decline phenomenon and identifying the critical habitat features essential for their success. New Zealand native frogs (Anura: Leiopelmatidae, Leiopelma, nine species) were formerly distributed throughout New Zealand, but habitat modification and predation by introduced mammalian predators have influenced recent (Holocene) extinctions and declines, reducing the fauna to four species with major range reductions. All extant Leiopelma are classified as threatened both nationally and internationally, creating an urgent need for species-specific behavioural research to support conservation management. I investigated activity, movement behaviour and microhabitat use of L. archeyi and L. pakeka for better evaluation of long term population viability and improved husbandry in captivity. L. archeyi is the smallest of the Leiopelma species and has been able to co-occur with introduced predators (e.g. rats), whereas L. pakeka is the largest, and the only natural population is confined to a predator-free island. I used a fine-scale tracking technique (i.e. non-toxic fluorescent powders) to track L. archeyi and L. pakeka movements throughout their activity periods when on the surface in their natural habitats, Whareorino Forest and Maud Island, respectively, to obtain detailed information on their activity patterns, movement behaviour, and microhabitat and retreat site use. I investigated in more detail L. pakeka retreat sites by measuring the dimensions of the retreat site entrances (width, height and diameter) as well as the activity inside those retreat sites. Lastly, I used long-term frog survey data to examine the indirect impacts (i.e. behavioural changes) ship rats (Rattus rattus) may have on L. archeyi by studying the microhabitat use and home range of this species in an area with and without rat control within Whareorino Forest. L. archeyi had a longer activity period than L. pakeka with the former being active up to two hours after sunrise, but L. pakeka moved more and further than L. archeyi during their activity periods. Additionally, L. archeyi had a smaller home range compared to L. pakeka which suggests more prominent site fidelity and more sedentary behaviour in this species. Both species actively sought out specific microhabitats among the ones that were available, either to use during movement or to use as retreat sites, but those microhabitat types also differed between species. L. archeyi were more often found above ground level than L. pakeka and tended to use microhabitats that provided cover. L. archeyi preferred to use trees as retreat sites (roots, branches or trunk) whereas L. pakeka used trees (roots) and rocks. L. pakeka retreat sites had lower and more stable temperatures than outside retreats. Frogs were active inside retreats with no evidence of sleep behaviour for at least the first few hours of retreat use. In the rat control area, L. archeyi used more soil, leaf litter and ferns, and were also more likely to be found at ground level than frogs in the presence of higher numbers of rats. Abiotic factors also influenced movement patterns and microhabitat selection of both species, affirming water balance and thermoregulation are important drivers in frog behaviour. Behavioural attributes and small body size could be aiding in the persistence of L. archeyi in the presence of rats, and large body size and differences in behavioural attributes are likely to put L. pakeka at risk if rats were to reach their habitat. My findings inform on the ecology and behaviour of two Leiopelma species providing valuable information on their habitat requirements, which will enable more effective captive husbandry and better assessment of the appropriateness of translocation sites, aiding in their conservation management.</p>


2021 ◽  
Author(s):  
◽  
Patty Ramírez

<p>Amphibian populations are in general decline internationally. The current situation of amphibian populations highlights the urgent need for comprehensive information on species’ ecology to better assess conservation and management strategies. Movement behaviour and microhabitat selection give insights into how amphibians use the environment and interact with their surroundings, and are essential to establishing their sensitivity to the global decline phenomenon and identifying the critical habitat features essential for their success. New Zealand native frogs (Anura: Leiopelmatidae, Leiopelma, nine species) were formerly distributed throughout New Zealand, but habitat modification and predation by introduced mammalian predators have influenced recent (Holocene) extinctions and declines, reducing the fauna to four species with major range reductions. All extant Leiopelma are classified as threatened both nationally and internationally, creating an urgent need for species-specific behavioural research to support conservation management. I investigated activity, movement behaviour and microhabitat use of L. archeyi and L. pakeka for better evaluation of long term population viability and improved husbandry in captivity. L. archeyi is the smallest of the Leiopelma species and has been able to co-occur with introduced predators (e.g. rats), whereas L. pakeka is the largest, and the only natural population is confined to a predator-free island. I used a fine-scale tracking technique (i.e. non-toxic fluorescent powders) to track L. archeyi and L. pakeka movements throughout their activity periods when on the surface in their natural habitats, Whareorino Forest and Maud Island, respectively, to obtain detailed information on their activity patterns, movement behaviour, and microhabitat and retreat site use. I investigated in more detail L. pakeka retreat sites by measuring the dimensions of the retreat site entrances (width, height and diameter) as well as the activity inside those retreat sites. Lastly, I used long-term frog survey data to examine the indirect impacts (i.e. behavioural changes) ship rats (Rattus rattus) may have on L. archeyi by studying the microhabitat use and home range of this species in an area with and without rat control within Whareorino Forest. L. archeyi had a longer activity period than L. pakeka with the former being active up to two hours after sunrise, but L. pakeka moved more and further than L. archeyi during their activity periods. Additionally, L. archeyi had a smaller home range compared to L. pakeka which suggests more prominent site fidelity and more sedentary behaviour in this species. Both species actively sought out specific microhabitats among the ones that were available, either to use during movement or to use as retreat sites, but those microhabitat types also differed between species. L. archeyi were more often found above ground level than L. pakeka and tended to use microhabitats that provided cover. L. archeyi preferred to use trees as retreat sites (roots, branches or trunk) whereas L. pakeka used trees (roots) and rocks. L. pakeka retreat sites had lower and more stable temperatures than outside retreats. Frogs were active inside retreats with no evidence of sleep behaviour for at least the first few hours of retreat use. In the rat control area, L. archeyi used more soil, leaf litter and ferns, and were also more likely to be found at ground level than frogs in the presence of higher numbers of rats. Abiotic factors also influenced movement patterns and microhabitat selection of both species, affirming water balance and thermoregulation are important drivers in frog behaviour. Behavioural attributes and small body size could be aiding in the persistence of L. archeyi in the presence of rats, and large body size and differences in behavioural attributes are likely to put L. pakeka at risk if rats were to reach their habitat. My findings inform on the ecology and behaviour of two Leiopelma species providing valuable information on their habitat requirements, which will enable more effective captive husbandry and better assessment of the appropriateness of translocation sites, aiding in their conservation management.</p>


2021 ◽  
pp. 197
Author(s):  
Suraidi Suraidi

This activity is carried out to share electronic knowledge to the public in the form of training. The training materials can be applied to everyday life, so that the trainees can have a clear picture of the material provided. In addition, introducing the science of electronics to high school students to open their knowledge of the science, so that high school students can see that electronics is an easy and interesting science. Partner problems are related to the shortage of human resources who have expertise in the field of electronics, so Untar's electrical engineering study program lecturers help meet these deficiencies by providing this training activity for the solution. The target of the training is high school students and is targeted to be able to make a home page lighting system using passive infrared (PIR) sensors. This system can be applied to various needs, one application is an anti-theft system to cause a shock effect if someone enters the yard at night and an electric power saving system for lighting. The PKM team will provide all training materials including consumables and training materials in the form of instructions on how to install the system. The activity period is from September to November 2021. This activity begins with collecting information about the system material to be made, experiments are carried out to make the system so that it is known with certainty what modules or components are used in the system. The training is scheduled offline and is carried out in several waves with the nature of the training being completed for one meeting a maximum of 2 hours. The method of this activity is by conducting electronics training and the activity takes place and is carried out at the Candle Tree High School. The teaching staff for electronics training are lecturers and students of Electrical Engineering at Tarumanagara University. The material taught is made in detail and gradually, training from the initial explanation to the creation of a complete system. Outcomes produced with finished products for high school students and seminars for lecturers who support this activity. Kegiatan ini dilakukan untuk membagikan ilmu elektronika kepada masyarakat dalam bentuk pelatihan. Materi pelatihan dapat diaplikasikan pada kehidupan sehari-hari, sehingga peserta pelatihan dapat mempunyai gambaran jelas tentang materi yang diberikan. Selain itu, memperkenalkan ilmu elektronika kepada siswa SMA untuk membuka wawasan mereka akan ilmu tersebut, sehingga siswa SMA dapat memandang bahwa ilmu elektronika adalah ilmu yang mudah dan menarik. Permasalahan mitra berhubungan kekurangan SDM yang mempunyai keahlian bidang elektronika, sehingga dosen prodi teknik elektro Untar membantu memenuhi kekurangan tersebut dengan memberikan kegiatan pelatihan ini sebagai solusinya. Sasaran pelatihan yaitu para siswa SMA dan ditargetkan mampu membuat sebuah sistem penerangan halaman rumah dengan menggunakan sensor passive infra red (PIR). Sistem ini dapat diaplikasikan untuk berbagai macam kebutuhan, salah satu aplikasinya adalah  sistem anti maling untuk menimbulkan efek kejut jika ada orang yang masuk ke pekarangan rumah pada malam hari dan sistem penghemat daya listrik untuk lampu penerangan. Tim PKM akan menyediakan semua bahan pelatihan termasuk bahan habis pakai dan materi pelatihan berupa petunjuk cara pemasangan sistem. Periode kegiatan pada bulan September sampai bulan November 2021. Kegiatan ini dimulai dengan mengumpulkan informasi tentang materi sistem yang akan dibuat, dilakukan percobaan untuk membuat sistem agar di ketahui dengan pasti modul atau komponen apa saja yang digunakan pada sistem.  Pelaksanaan pelatihan dijadwalkan secara luring dan dilakukan beberapa gelombang dengan sifat pelatihan selesai untuk satu kali pertemuan maksimal 2 jam.. Metode kegiatan ini dengan melakukan pelatihan elektronika dan kegiatan berlangsung dan dilaksanakan di sekolah SMA Candle Tree. Tenaga pengajar pelatihan elektronika adalah dosen dan mahasiswa Teknik Elektro Universitas Tarumanagara. Materi yang diajarkan dibuat secara detail dan bertahap, pelatihan dari penjelasan awal sampai dengan pembuatan sistem secara lengkap. Luaran yang dihasilkan dengan produk jadi bagi siswa SMA dan seminar bagi dosen pengampu kegiatan ini.


2021 ◽  
Vol 13 (12) ◽  
Author(s):  
Sara E. Rhodes ◽  
Nicholas J. Conard

AbstractEnsuring comparability between results is a key goal of all paleoecological reconstructions. Quantitative estimates of meteorological variables, as opposed to relative qualitative descriptions, provide the opportunity to compare local paleoenvironmental records against global estimates and incrementally build regional paleoclimatic records. The Bioclimatic Method provides quantitative and qualitative estimates of past landscape composition and climate along with measures of statistical accuracy by applying linear discriminant functions analysis and transfer functions to faunal taxonomic abundance data. By applying this method to the rodent data from Geißenklösterle and Hohle Fels, two Paleolithic cave sites located in the Ach Valley of southwestern Germany, we classify the regional vegetation according to Walters’ zonobiome model. We also present new estimates of meteorological variables including mean annual temperature, mean annual precipitation, and vegetative activity period of the Ach Valley for the period spanning ~ 60,000 to 35,000 cal BP. The results suggest the Ach Valley contained a non-analogous landscape of arctic tundra and temperate deciduous woodland with occasional arid steppe expansion. Meteorological estimates suggest the climate was significantly colder during the Middle and Upper Paleolithic than today, with higher annual precipitation and dramatic temperature shifts between seasons. These results fit well with climatic reconstructions from Switzerland and the Netherlands based on a variety of proxies. They also provide further evidence of a localized climatic response within southwestern Germany to the stadial-interstadial shifts preceding the Heinrich 4 event. Finally, these results reinforce our previous claims that climatic volatility was not a driving force in the loss of Neanderthal groups throughout the Swabian Jura during OIS 3.


2021 ◽  
Author(s):  
◽  
Kelly Maree Hare

<p>Paradoxically, nocturnal lizards prefer substantially higher body temperatures than are achievable at night and are therefore active at thermally suboptimal temperatures. In this study, potential physiological mechanisms were examined that may enable nocturnal lizards to counteract the thermal handicap of activity at low temperatures: 1) daily rhythms of metabolic rate, 2) metabolic rate at low and high temperatures, 3) locomotor energetics, and 4) biochemical adaptation. A multi-species approach was used to separate evolutionary history of the species from any potential links between physiology and activity period. Four to eight species of lizards, encompassing nocturnal and diurnal lizards from the families Diplodactylidae and Scincidae, were used for all physiological measurements. Three daily patterns of metabolic rate (VO2) were apparent depending on the species: 24 h cycles, 12 h cycles, and no daily cycle. The daily patterns of VO2 and peak VO2 did not always coincide with the activity period of the species. All nocturnal lizards tested had a lower energetic cost of locomotion (Cmin) than diurnal lizards. Diurnal lizards from New Zealand also had low Cmin values when compared with nocturnal geckos and diurnal lizards from lower latitudes. Thus, a low Cmin appears to be related to activity at low temperatures rather than specifically to nocturnality. However, more data are required on lizards from high latitudes, including more New Zealand lizards, before the generality of this pattern can be confirmed. Also, based on correlations with lizards active at warmer temperatures, a low Cmin only partially offsets the thermal handicap imposed on lizards that are active at low temperatures. Nocturnal lizards were found to have lower thermal sensitivities of metabolism (lower Q10 values) than diurnal lizards, indicating that their energy-dependent activity was not as sensitive to changes in environmental temperature. The similarity of other metabolic processes among species with differing activity periods may be partly explained by the ability of nocturnal species to thermoregulate to achieve higher temperatures during the day. The amplitudes of daily VO2 cycles and mass-specific VO2 did not differ among nocturnal and diurnal New Zealand lizards at low temperatures. The specific activity of the glycolytic enzyme lactate dehydrogenase (LDH) isolated from the tail muscle of lizards was also comparable among nocturnal and diurnal lizards over a range of biologically relevant temperatures. Thus, activity of lizards at low temperatures is not enabled by lower energy requirements over a 24 h period, elevation of metabolic rates, or biochemical adaptation of LDH to specific temperatures. These results confirm that locomotion is more efficient in nocturnal lizards and diurnal lizards from New Zealand than lizards from elsewhere, but that other metabolic processes do not appear to differ among species. Additional physiological and behavioural adaptations may exist that complement the increased efficiency of locomotion, thus enabling nocturnal lizards to be active at low temperatures.</p>


2021 ◽  
Author(s):  
◽  
Kelly Maree Hare

<p>Paradoxically, nocturnal lizards prefer substantially higher body temperatures than are achievable at night and are therefore active at thermally suboptimal temperatures. In this study, potential physiological mechanisms were examined that may enable nocturnal lizards to counteract the thermal handicap of activity at low temperatures: 1) daily rhythms of metabolic rate, 2) metabolic rate at low and high temperatures, 3) locomotor energetics, and 4) biochemical adaptation. A multi-species approach was used to separate evolutionary history of the species from any potential links between physiology and activity period. Four to eight species of lizards, encompassing nocturnal and diurnal lizards from the families Diplodactylidae and Scincidae, were used for all physiological measurements. Three daily patterns of metabolic rate (VO2) were apparent depending on the species: 24 h cycles, 12 h cycles, and no daily cycle. The daily patterns of VO2 and peak VO2 did not always coincide with the activity period of the species. All nocturnal lizards tested had a lower energetic cost of locomotion (Cmin) than diurnal lizards. Diurnal lizards from New Zealand also had low Cmin values when compared with nocturnal geckos and diurnal lizards from lower latitudes. Thus, a low Cmin appears to be related to activity at low temperatures rather than specifically to nocturnality. However, more data are required on lizards from high latitudes, including more New Zealand lizards, before the generality of this pattern can be confirmed. Also, based on correlations with lizards active at warmer temperatures, a low Cmin only partially offsets the thermal handicap imposed on lizards that are active at low temperatures. Nocturnal lizards were found to have lower thermal sensitivities of metabolism (lower Q10 values) than diurnal lizards, indicating that their energy-dependent activity was not as sensitive to changes in environmental temperature. The similarity of other metabolic processes among species with differing activity periods may be partly explained by the ability of nocturnal species to thermoregulate to achieve higher temperatures during the day. The amplitudes of daily VO2 cycles and mass-specific VO2 did not differ among nocturnal and diurnal New Zealand lizards at low temperatures. The specific activity of the glycolytic enzyme lactate dehydrogenase (LDH) isolated from the tail muscle of lizards was also comparable among nocturnal and diurnal lizards over a range of biologically relevant temperatures. Thus, activity of lizards at low temperatures is not enabled by lower energy requirements over a 24 h period, elevation of metabolic rates, or biochemical adaptation of LDH to specific temperatures. These results confirm that locomotion is more efficient in nocturnal lizards and diurnal lizards from New Zealand than lizards from elsewhere, but that other metabolic processes do not appear to differ among species. Additional physiological and behavioural adaptations may exist that complement the increased efficiency of locomotion, thus enabling nocturnal lizards to be active at low temperatures.</p>


2021 ◽  
Vol 8 (Supplement_1) ◽  
pp. S61-S61
Author(s):  
Victoria Divino ◽  
Maarten Postma ◽  
Stephen I Pelton ◽  
Joaquin F Mould-Quevedo ◽  
Ruthwik Anupindi ◽  
...  

Abstract Background Changes in the influenza hemagglutinin protein during replication of influenza in eggs during vaccine production may contribute to low vaccine effectiveness (VE). This phenomenon, egg adaptation, can explain VE differences between egg-based (QIVe-SD) and cell-based (QIVc) quadrivalent influenza vaccines. This research evaluated the relative vaccine effectiveness (rVE) of QIVc versus QIVe-SD in the reduction of influenza-related and any respiratory-related hospitalizations/emergency room (ER) visits among subjects 4-64 years old during the 2019/20 influenza season. Methods A retrospective cohort analysis was conducted among subjects 4-64 years old vaccinated with QIVc or QIVe-SD using administrative claims data in the U.S. (IQVIA PharMetrics® Plus). The adjusted number of events and rates of influenza-related hospitalizations/ER visits and respiratory-related hospitalizations/ER visits were assessed using inverse probability of treatment weighting (IPTW). Poisson regression was used to estimate relative vaccine effectiveness (rVE). In the main analysis, the study period was from Aug 4, 2019 to Mar 7, 2020 (ending early to avoid any influenza outcome misclassification with COVD-19 infection). In the assessment of the high influenza activity period (HIAP), the analysis period was restricted to Dec 8, 2019 to Mar 7, 2020. Results During the 2019/20 influenza season, 1,150,134 recipients of QIVc and 3,924,819, of QIVe-SD were identified following IPTW. In the main analysis, adjusted results show that QIVc was associated with a significantly higher rVE compared to QIVe-SD against influenza-related hospitalizations/ER visits (5.3% [95%CI: 0.5%-9.9%]) and respiratory-related hospitalizations/ER visits (8.2% [95%CI: 6.5%-9.8%]). Similarly, in the HIAP analysis, QIVc was associated with a significantly higher rVE compared to QIVe-SD for influenza-related hospitalizations/ER visits (5.7% [95%CI: 0.8%-10.4%]) and respiratory-related hospitalizations/ER visits (7.3% [95%CI: 5.4%-9.2%]). Conclusion QIVc was more effective in preventing influenza-related and respiratory-related hospitalizations/ER visits compared to QIVe-SD, using either a broad influenza season definition or restricting to the HIAP. Disclosures Victoria Divino, PhD, Seqirus (Consultant) Maarten Postma, Dr., Seqirus (Consultant) Stephen I. Pelton, MD, Seqirus (Consultant) Joaquin F. Mould-Quevedo, PhD, Seqirus (Employee) Ruthwik Anupindi, PhD, Seqirus (Consultant) Mitchell DeKoven, PhD, Seqirus (Consultant) myron J. levin, MD, GSK group of companies (Employee, Research Grant or Support)


2021 ◽  
Vol 14 (3-4) ◽  
pp. 39-46
Author(s):  
Tamás Bartyik ◽  
György Sipos ◽  
Dávid Filyó ◽  
Tímea Kiss ◽  
Petru Urdea ◽  
...  

Abstract River Maros/Mureş has one of the largest alluvial fans in the Carpathian Basin. On the surface of the fan several very wide, braided channels can be identified, resembling increased discharges during the Late Glacial. In our study we investigated the activity period of the largest channel of them, formed under a bankfull discharge three times higher than present day values. Previous investigations dated the formation of the palaeochannel to the very end of the Pleistocene by dating a point bar series upstream of the selected site. Our aim was to obtain further data on the activity period of the channel and to investigate temporal relationships between maximum palaeodischarges, deglaciation phases on the upland catchment and climatic amelioration during the Late Pleistocene. The age of sediment samples was determined by optically stimulated luminescence (OSL). The investigation of the luminescence properties of the quartz extracts also enabled the assessment of sediment delivery dynamics in comparison to other palaeochannels on the alluvial fan. OSL age results suggest that the activity of the channel is roughly coincident with, but slightly older than the previously determined ages, meaning that the main channel forming period started at 13.50±0.94 ka and must have ended by 8.64±0.82 ka. This period cannot directly be related to the major phases of glacier retreat on the upland catchments, and in terms of other high discharge channels only the activity of one overlaps with a major deglaciation phase at ~17-18 ka. Based on these, high palaeodischarges can be rather related to increased Late Glacial runoff, resulted by increasing precipitation and scarce vegetation cover on the catchment. Meanwhile, the quartz luminescence sensitivity of the investigated channel refers to fast sediment delivery from upland subcatchments. Therefore, the retreat of glaciers could affect alluvial processes on the lowland by increasing sediment availability, which contributed to the development of large braided palaeochannels.


2021 ◽  
Vol 22 (11) ◽  
Author(s):  
MANANYA PLA-ARD ◽  
NORASET KHIOESREE ◽  
BUNYATIPORN KEAWDEE ◽  
WIPAVEE HUNGHENG ◽  
PATTANAPHON CHATTRAKULDEE ◽  
...  

Abstract. This study on the monitoring of the diversity and abundance of wildlife around the wildlife corridor area on Highway 304, which passes through Khao Yai and Thap Lan National Parks, was conducted during September 2017 and May 2021 using camera traps to constantly monitor the area. A total of at least 51 wildlife species from 30 families, 14 orders were recorded. The species with the highest abundances were Sambar Deer, Wild Boar, Northern Pig-tailed Macaque, Gaur, Northern Red Muntjac, Siamese Fireback, Malayan Porcupine, Red Junglefowl, etc. The wildlife species recorded include 2 critically endangered species, 3 endangered, 10 vulnerable, 1 near threatened. In this study we also recorded images of a Fishing Cat, which is the first photographically record in this World Heritage Site. The evenness index indicates that the wildlife community in the area is stable. No significant differences in the diversity and abundance of wildlife before or after the corridor construction were seen. The wildlife in the area were active throughout the day. We also found that the highway is the main factor effecting the presence of wildlife. The study results show the importance of this area that the highway passes through. Building wildlife corridors between the two national parks is very important for maintaining the wildlife community as well as continuity. Suggestions from the study include management of human activity in the area including traffic, noise, vehicle speed and living activities in the area that may attract wildlife closer to the community and cause other impacts.


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