Top PDF Ergosterol, arabitol and mannitol as tracers for biogenic aerosols in the eastern Mediterranean

Ergosterol, arabitol and mannitol as tracers for biogenic aerosols in the eastern Mediterranean

Ergosterol, arabitol and mannitol as tracers for biogenic aerosols in the eastern Mediterranean

Estimating the concentration of fungi in the atmosphere is commonly conducted using viable samplers or spore traps. With viable samplers it is possible to enumerate only live species, while spore traps followed by microscopic exami- nation can provide total spore counts regardless of their via- bility. Both approaches provide number concentrations and species identification, but they are labor-intensive and time consuming. They do not provide the contribution of fun- gal spores to atmospheric aerosols in terms of mass load- ing or impacts (Lau et al., 2006). To quantify and identify fungi contribution to atmospheric aerosols and the impact to public health, it has been suggested to use biomarkers in chemical analysis of collected aerosols. An often used biomarker for determining the fungal biomass is ergosterol (Lau et al., 2006), which is a primary fungal membrane sterol shown in Fig. 1a. Ergosterol is almost exclusively found in fungi and is therefore an efficient biomarker. Photochem- ical degradation can cause a significant decrease of ergos- terol content in living fungi, therefore it is necessary to avoid light exposure once the fungi are collected (Mille-Lindblom et al., 2004). Gas Chromatography-Mass Spectrometry (GC- MS) is the most efficient mean for determination ergosterol (Miller and Young, 1997). Trimethylsilyl derivatization of ergosterol is often used for increasing the detection sensitiv- ity. The derivatization occurs by replacing the hydrogen from the OH group by a trimethylsilyl group (Saraf et al., 1997).
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Fluorescent bioaerosol particle, molecular tracer, and fungal spore concentrations during dry and rainy periods in a semi-arid forest

Fluorescent bioaerosol particle, molecular tracer, and fungal spore concentrations during dry and rainy periods in a semi-arid forest

site of spore growth. When the spores are ejected, some of the fluid adheres to the spores and becomes aerosolized. Several of these secreted compounds are thought to enter the atmo- sphere linked uniquely with spore emission processes, and so these tracers have been used to estimate atmospheric con- centrations of fungal spores. Arabitol and mannitol are both sugar alcohols (polyols) that serve as energy stores for the spore (Feofilova, 2001). Arabitol is unique to fungal spores and lichen, while mannitol is present in fungal spores, lichen, algae, and higher plants (Lewis and Smith, 1967). Ergosterol is found within the cell membranes of fungal spores (Weete, 1973) and has been used as an ambient fungal spore tracer (Di Filippo et al., 2013; Miller and Young, 1997). Compar- ing the seasonal trends of arabitol and mannitol with ergos- terol, Burshtein et al. (2011) showed positive correlations be- tween arabitol or mannitol and ergosterol only in the spring and autumn, suggesting that the source of these polyols is unlikely to be solely fungal in origin or that the amount of each compound emitted varies considerably between species type and season. While ergosterol has been directly linked to fungal spores in the air, ergosterol is prone to photochem- ical degradation and is difficult to analyze and quantify di- rectly. Quantification of ergosterol typically requires chemi- cal derivatization by silylation before analysis via gas chro- matography (Axelsson et al., 1995; Burshtein et al., 2011; Lau et al., 2006). In contrast, analysis of sugar alcohols by ion chromatography involves fewer steps and has been suc- cessfully applied to monitor seasonal variations of atmo- spheric aerosol concentration at a number of sites (Bauer et al., 2008a; Caseiro et al., 2007; Yang et al., 2012; Yttri et al., 2011a; Zhang et al., 2010, 2015) including pg m −3 (picograms per cubic meter) levels in the Antarctic (Barbaro et al., 2015). By measuring spore count and tracer concen- tration in parallel at one urban and two suburban sites in Vienna, Austria, Bauer et al. (2008a) estimated the amount of each tracer per fungal spore emitted. Potassium ions have also been linked to emission of biogenic aerosol (Pöhlker et al., 2012b) and are co-emitted with fungal spores; however, application of potassium as a fungal tracer is uncommon because it is predominantly associated with biomass burn- ing (Andreae and Crutzen, 1997). Additionally, (1→3)-β- D-glucan (fungal spores and pollen) and endotoxins (gram- negative bacteria) have also been widely used to measure other bioaerosols (Andreae and Crutzen, 1997; Cheng et al., 2012; Rathnayake et al., 2016b; Stone and Clarke, 1992).
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Fungal spores overwhelm biogenic organic aerosols in a midlatitudinal  forest

Fungal spores overwhelm biogenic organic aerosols in a midlatitudinal forest

Abstract. Both primary biological aerosol particles (PBAPs) and oxidation products of biogenic volatile organic com- pounds (BVOCs) contribute significantly to organic aerosols (OAs) in forested regions. However, little is known about their relative importance in diurnal timescales. Here, we re- port biomarkers of PBAP and secondary organic aerosols (SOAs) for their diurnal variability in a temperate conifer- ous forest in Wakayama, Japan. Tracers of fungal spores, trehalose, arabitol and mannitol, showed significantly higher levels in nighttime than daytime (p < 0.05), resulting from the nocturnal sporulation under near-saturated relative hu- midity. On the contrary, BVOC oxidation products showed higher levels in daytime than nighttime, indicating substan- tial photochemical SOA formation. Using tracer-based meth- ods, we estimated that fungal spores account for 45 % of organic carbon (OC) in nighttime and 22 % in daytime, whereas BVOC oxidation products account for 15 and 19 %, respectively. To our knowledge, we present for the first time highly time-resolved results that fungal spores overwhelmed BVOC oxidation products in contributing to OA especially in nighttime. This study emphasizes the importance of both PBAPs and SOAs in forming forest organic aerosols.
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Temporal variability and sources of VOCs in urban areas of the eastern Mediterranean

Temporal variability and sources of VOCs in urban areas of the eastern Mediterranean

used as the reaction reagent for the PTR-MS. The drift tube was operated at a pressure of 2.2–2.3 mbar and its voltage was 600 V. The inlet flow was 0.5 L min −1 and the inlet tube and reaction chamber were heated to 60 ◦ C. The residence time in the sampling lines prior to the PTR-MS was 10 s for the Patras summer campaign, 12 s for the Athens summer campaign, and 16 s for the Athens winter campaign. The cor- responding ratio of the electric field strength to the gas num- ber density was approximately 126 Td (1 Td = 10 −17 V cm 2 ). Blanks were obtained at regular intervals through an acti- vated carbon filter (Supelpure HC, Supelco). A Teflon filter was installed before the sampling inlet. Concentrations were monitored in the multiple ion detection (MID) mode with a total cycle time of 10 s. The dwell times were in the range of 5–500 ms. A 200 ms dwell time was used for most of the re- ported m/z values. For some of the higher m/z values a dwell time of 500 ms was selected. The dwell times for m/z 21, 30, 32, and 37 were 200, 5, 5, and 10 ms respectively in all three campaigns.
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The Mediterranean and Black Sea fisheries at risk from overexploitation.

The Mediterranean and Black Sea fisheries at risk from overexploitation.

Given that global fishing effort remains the same or increases with time, as it also does in the Mediterranean Sea [53], a decline in total catches, which is actually a decline in catch per unit of effort (CPUE), can be considered as a suspicion or indication of overfishing. There are a few well-documented examples where CPUE successfully tracks the stock size [54] but this is not always the case. In cases where fishing mortality follows predictable dynamics over time, catch data can be used to reconstruct biomass and potentially used for conducting data-poor assessments [55]. Declines in CPUE have been reported for the vast majority of FAO areas, in- cluding the Mediterranean Sea, where a drastic CPUE decline is apparent since the late 1990s [1]. The more or less stable total catches of the W Mediterranean, but with a declining trend during the last decade, is probably the result of exploiting new species, as revealed by the num- ber of added records per year (Fig. 2), and to improving management practices as revealed by the larger number of stocks that are regularly assessed [9]. The declining trend of C Mediterra- nean total catches after mid 1980s and of the E Mediterranean ones after mid 1990s (Fig. 3), is a clear effect of excessive fishing mortality applied on these stocks [42] and the alteration and simplification of the food web structure over time as a result of fishing [35,56]. Overfishing and its side effects on ecosystem have been blamed for the collapse of Black Sea fisheries in early 1990s and the decline in total catches [28]. Some catch fluctuations, however, especially those of the small and medium pelagic fishes that are highly represented in the catches, could be the result of climatic effects [57] or modifications in the planktonic production [58].
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Mesoscale modeling of combined aerosol and photo-oxidant processes in the eastern Mediterranean

Mesoscale modeling of combined aerosol and photo-oxidant processes in the eastern Mediterranean

with also significant amounts of nitrate, ammonium and organics. In general the area of the eastern Mediterranean is moderately to highly polluted during summer with a contribution from the main urban conglomerations, whereas during the winter period the particulate matter and oxidant concentrations are lower than the summer values. Acknowledgements. This work was supported by the European Commission under grant

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Ground based measurements of immersion-freezing in the eastern Mediterranean

Ground based measurements of immersion-freezing in the eastern Mediterranean

concentrations and AF values than clean days. These differences (> 2.5 times) were smaller than what was found in other places (such as Germany and the US). This agrees with previous reports showing that the eastern Mediterranean atmosphere al- ways contains some dust particles and therefore their effect on IN concentrations is to generally raise the background level.

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Morphological variation in eight species sparidae of the eastern atlantic and mediterranean sea

Morphological variation in eight species sparidae of the eastern atlantic and mediterranean sea

Pagellus bogaraveo (Brunnich. 1768), common dentex, Dentex dentex (Linnaeus, 1758), and black seabream, Spondyliosoma cantharus (Linnaeus, 1758) as well as the hybrid Sparus auraía x P[r]

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CESM/CAM5 improvement and application: comparison and evaluation of updated CB05_GE and MOZART-4 gas-phase mechanisms and associated impacts on global air quality and climate

CESM/CAM5 improvement and application: comparison and evaluation of updated CB05_GE and MOZART-4 gas-phase mechanisms and associated impacts on global air quality and climate

Granier, C., Bessagnet, B., Bond, T., D’Angiola, A., Denier van der Gon, H., Frost, G. J., Heil, A., Kaiser, J. W., Kinne, S., Klimont, Z., Kloster, S., Lamarque, J.-F., Liousse, C., Masui, T., Meleux, F., Mieville, A., Ohara, T., Raut, J.-C., Riahi, K., Schultz, M. G., Smith, S. J., Thomp- son, A., van Aardenne, J., van der Werf, G. R., and van Vuuren, D. P.: Evolution of anthro- pogenic and biomass burning emissions of air pollutants at global and regional scales during

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Comparing flood mortality in Portugal and Greece (Western and Eastern Mediterranean)

Comparing flood mortality in Portugal and Greece (Western and Eastern Mediterranean)

In both countries flood victims are mostly males, showing that males are more exposed to fatal floods. Gender is an individual vulnerability factor that controls the access to opportunities and exposure to risks [6]. Gender differences in natural hazards can be expected to occur where there are gender di fferences in social roles that result in exposure to different environments [70]. Male mortality dominance associated with floods has been widely referred in the literature specially in developed countries [17,18,51]. These gender differences can be explained by cultural reasons, that expose men to hazardous occupations (e.g. work in emergency services) or risk behaviours (e.g., driving a car in flooded roads, cross bridges in flood situations) because drivers often underestimate the force of the flowing water [6,19].
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	Field Cancerisation of the Upper Aerodigestive Tract: Screening for Second Primary Cancers of the Oesophagus in Cancer Survivors

Field Cancerisation of the Upper Aerodigestive Tract: Screening for Second Primary Cancers of the Oesophagus in Cancer Survivors

Tobacco, alcohol, and betel quid are the main causes of squamous cell cancers of the upper aerodigestive tract. These substances can cause multifocal carcinogenesis leading to multiple synchronous or metachronous cancers of the oesophagus, head and neck region, and lungs (‘ield cancerisation’). Globally there are several million people who have survived either head and neck squamous cell cancer (HNSCC) or lung cancer (LC). HNSCC and LC survivors are at increased risk of developing second primary malignancies, including second primary cancers of the oesophagus. The risk of second primary oesophageal squamous cell cancer (OSCC) ranges from 8-30% in HNSCC patients. LC and HNSCC survivors should be ofered endoscopic surveillance of the oesophagus. Lugol chromoendoscopy is the traditional and best evaluated screening method to detect early squamous cell neoplasias of the oesophagus. More recently, narrow band imaging combined with magnifying endoscopy has been established as an alternative screening method in Asia. Low-dose chest computed tomography (CT) is the best evidence- based screening technique to detect (second primary) LC and to reduce LC-related mortality. Low-dose chest CT screening is therefore recommended in OSCC, HNSCC, and LC survivors. In addition, OSCC survivors should undergo periodic pharyngolaryngoscopy for early detection of second primary HNSCC. Secondary prevention aims at quitting smoking, betel quid chewing, and alcohol consumption. As ield cancerisation involves the oesophagus, the bronchi, and the head and neck region, the patients at risk are best surveilled and managed by an interdisciplinary team.
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Particle sized-resolved source apportionment of primary and   secondary organic tracer compounds at urban and rural locations in   Spain

Particle sized-resolved source apportionment of primary and secondary organic tracer compounds at urban and rural locations in Spain

Edney, E. O., Kleindienst, T. E., Jaoui, M., Lewandowski, M., Offenberg, J. H., Wang, W., and Cleays, M.: Formation of 2-methyltetrols and 2-methylglyceric acid in secondary aerosol from laboratory irradiated isoprene/NO x /SO 2 /air mixture and their detection in ambient air PM 2.5 samples collected in the eastern United States, Atmos. Environ., 39, 5281–5289, 2005. El Haddad, I., Marchand, N., Temime-Roussel, B., Wortham, H., Piot, C., Besombes, J.-L.,

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Lightning flash multiplicity in eastern Mediterranean thunderstorms

Lightning flash multiplicity in eastern Mediterranean thunderstorms

Cummins et al. (1998a) mention that the average multi- plicity was generally thought to be between 3 and 4, as found by Thomson et al. (1984). The multiplicity values determined by the NLDN according to the two different methods (the pre- and post-upgrade algorithms) for two years after the upgrade were different. The result obtained using the new method was lower (1.9) than the result obtained for the same database by the previous method (2.7). Orville et al. (2002) analyzed three years of data from the NLDN and found that in most regions the mean negative multiplicity was lower than 2.6. In general, multiplicity increases with higher nega- tive peak currents (first stroke peak current). Analyzing 10 yr of lightning data from the NLDN (1989–1998), Orville and Huffins (2001) found that the negative multiplicity is slightly above 2.5 for the period 1989–1994, subsequently decreas- ing to slightly over 2.0 during the period 1995–1998. They attribute the results to the multiplicity algorithm change in 1994. Rakov and Huffins (2003) summarize different stud- ies from Florida, New Mexico, Sri Lanka and Sweden, all of which found that less than 20 % are single-stroke flashes. The mean negative multiplicity reported by Orville et al. (2010) for the years 2001–2009 ranges between 2.2–2.6. The multi- plicity values are affected by improved detection ability as a result of some upgrades to the NLDN, which consist of 200 sensors (in 2010). For example, a higher negative multiplic- ity was reported for 2002 compared to 2001 and a 30 % in- crease in positive multiplicity from 2001 to 2004, following the 2002–2003 upgrade. The mean multiplicity for the Aus- trian Lightning Detection and Information System (ALDIS) was 2.21 and for the FM-System m = 2.29 (Schulz and Di- endorfer, 2006). In Brazil, the average multiplicity of nega- tive CG flashes reported by BrasilDat was 1.9, but this may have been an underestimation due to the low stroke detec- tion efficiency of the network at that period of time (Pinto et al., 1999). Matsui and Hara (2011) analyzed lightning data in Japan and conducted a comparison of the NLDN criteria with those used by the JLDN. The mean negative multiplicity was found to be 2.13 and the positive multiplicity was 1.18. They found that the NLDN criteria tend to slightly overestimate the multiplicity values (2.23 and 1.19, respectively), because the NLDN assigns strokes into flashes in larger areas com- pared with the JLDN. The distribution of multiplicity values for the two algorithms is only marginally different (Figs. 3 and 4).
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Biogenic influence on cloud microphysics over the global ocean

Biogenic influence on cloud microphysics over the global ocean

Cape Hedo is the northern tip of Okinawa Island (26.9 ◦ N–128 ◦ E), located between Japan main islands and Taiwan. The station is downwind of important urban and in- dustrial aerosol sources, and it is also affected by biomass burning and Asian dust transport (Takami et al., 2006; Lana et al., 2011c). This was the only examined station where monthly MSA and γDMSflux data did not agree (Fig. 3f); this had been observed

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Aerosol and precipitation chemistry measurements in a remote site in Central Amazonia: the role of biogenic contribution

Aerosol and precipitation chemistry measurements in a remote site in Central Amazonia: the role of biogenic contribution

the dry season but also for the April–June months, due to the establishment of more favorable meteorological conditions to the transport of Atlantic air masses to Central Amazonia. The chemical composition of rainwater was similar to those ones observed in other remote sites in tropical forests. The volume-weighted mean (VWM) pH was 4.90. The most im- portant contribution to acidity was from weak organic acids. The organic acidity was predominantly associated with the presence of acetic acid instead of formic acid, which is more often observed in pristine tropical areas. Wet deposition rates for major species did not differ significantly between dry and wet season, except for NH + 4 , citrate and acetate, which had smaller deposition rates during dry season. While biomass burning emissions were clearly identified in the aerosol com- ponent, it did not present a clear signature in rainwater. The biogenic component and the long-range transport of sea salt were observed both in aerosols and rainwater composition. The results shown here indicate that in Central Amazonia it is still possible to observe quite pristine atmospheric condi- tions, relatively free of anthropogenic influences.
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Eastern Mediterranean Sea circulation inferred from the conditions of S1 sapropel deposition

Eastern Mediterranean Sea circulation inferred from the conditions of S1 sapropel deposition

Figure 4. The last 23 kyr variability of proxies for ventilation (U / Al, Mo / Al and benthic foraminiferal density) and wet or fresh conditions (Ti / Al and seawater δ 18 O anomaly) based on core MD04-2722 results as compared with previous studies. The sur- face water δ 18 O anomaly was calculated by combining the G. ru- ber δ 18 O record from core MD04-2722 with the SST reconstruction (see text for detail). Suboxic conditions on the Nile deep fan were estimated to have lasted from 12 to 7 cal ka BP at the “buildups”’ location (Fig. 1a and b) (Bayon et al., 2013). Benthic foraminiferal δ 13 C records were based on the epibenthic foraminifer species Planulina ariminensis (Kuhnt et al., 2007; Schmiedl et al., 2010). Changes in Nile River discharge are shown with the log scale Fe / Ca ratio for core MS27PT, located close to the Rosetta Mouth of the Nile River (Revel et al., 2014). The precession parameter is from Laskar et al. (2004). The blue zone indicates the African Hu- mid Period (AHP, 12.5–5.5 cal ka BP) based on Adkins et al. (2006) and deMenocal et al. (2000). The grey band indicates the S1 pe- riod from 10.4 to 6.8 cal ka BP, estimated for core MD04-2722. The dashed line presents the possible onset for weaker ventilation at 15 cal ka BP in the eastern Mediterranean Sea. LGM: Last Glacial Maximum.
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Dust–air pollution dynamics over the eastern Mediterranean

Dust–air pollution dynamics over the eastern Mediterranean

Abstract. Interactions of desert dust and air pollution over the eastern Mediterranean (EM) have been studied, focusing on two distinct dust transport events on 22 and 28 Septem- ber 2011. The atmospheric chemistry–climate model EMAC has been used at about 50 km grid spacing, applying an on- line dust emission scheme and calcium as a proxy for dust reactivity. EMAC includes a detailed tropospheric chem- istry mechanism, aerosol microphysics and thermodynam- ics schemes to describe dust “aging”. The model is evalu- ated using ground-based observations for aerosol concentra- tions and aerosol optical depth (AOD) as well as satellite observations. Simulation results and back trajectory analy- sis show that the development of synoptic disturbances over the EM can enhance dust transport from the Sahara and Ara- bian deserts in frontal systems that also carry air pollution to the EM. The frontal systems are associated with precipitation that controls the dust removal. Our results show the impor- tance of chemical aging of dust, which increases particle size, dust deposition and scavenging efficiency during transport, overall reducing the lifetime relative to non-aged dust parti- cles. The relatively long travel periods of Saharan dust result in more sustained aging compared to Arabian dust. Sensi- tivity simulations indicate 3 times more dust deposition of aged relative to pristine dust, which significantly decreases the dust lifetime and loading.
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Human Capital and the Recent Fall of Earnings Inequality in Brazil

Human Capital and the Recent Fall of Earnings Inequality in Brazil

where is a set of linear restrictions that transforms the unrestricted model (1) on restricted model (2). 8 In our case, the restriction implies that the age, trend and (orthogonal) time dummies are sufficient to explain the behavior of each estimated statistic order across cells and over time. Imposing the restrictions means estimating weighted least squares regressions on the grouped data, for each quantile and education group separately. This procedure will give us consistent estimates of . Under the null that the restrictions are valid, the minimized value follows a chi-square distribution with degrees of freedom equal to the number of restrictions. In order to construct the test statistics, we only have to sum up the weighted squared residuals, that is, the estimated percentiles minus the predicted values minus the orthogonal time dummies.
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Photochemical production of ammonium in the oligotrophic Cyprus Gyre (Eastern Mediterranean)

Photochemical production of ammonium in the oligotrophic Cyprus Gyre (Eastern Mediterranean)

These were then immediately capped with Nylon compression fittings (Swagelok ™ ) and placed in a shallow deck incubator, which was continuously flushed with ambient surface seawater. The irradiations ran for ≤3 h around local solar noon, with sequen- tial sampling for dissolved NH + 4 . Dark control flasks were treated identically, except that they were wrapped in double aluminium foil to exclude light. All irradiations were carried

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SOCIAL INEQUALITIES AND DECENTRALIZATION. THEORETICAL VIEWPOINTS AND EVIDENCES FROM THE HEALTH SYSTEM REFORM IN ROMANIA

SOCIAL INEQUALITIES AND DECENTRALIZATION. THEORETICAL VIEWPOINTS AND EVIDENCES FROM THE HEALTH SYSTEM REFORM IN ROMANIA

relationship between the public and private sector . Despite the important role played by the human resources, even in the fulfillment and implementation of the reforms mentioned also in the matters of system performance, efficiency and equity, this chapter didn`t form and doesn`t form a proprietary element although it is not totally ignored Buchan, . For instance, an entire spectrum of problems can correlate to the problematic of human resources having in view the supposedly improvement of the system through reforms: motivation of personnel, lack of stimulation, inequitable distribution of personnel, lack of supervision, difficulties to recruit qualified personnel, migration of the qualified personnel, etc. Beyond the obvious fact that these issues affect the health and the health conditions of the population in general, of major importance is to admit that these problems cannot be sepa- rated by the current changes that are taking place in the health system. )n fact, passing from a decentralized system has a notable impact in the matters of personnel. This fact is visible from two angles: First, the decentralization of resources, of authorities and of responsibilities highlighted these personnel issues. The dissipation of authority towards the autonomous units and the diminish of central control have placed on the agenda of the state authorities from lower level the problem of human resources so that problems and contradictions within the sector can no longer be totally credited to inefficiencies and bureaucracy at central level although the central state is guilty of leaving and de-standardizing the sector without forecasting the effects and the ways to absorb the eliminated parts in the system . Second of all, decentralization has had a mixed impact on the management of human resources. )f decentralization can be associated with a more adaptable and more flexible management of human resources, it can also generate on the other hand, problems especially where decentra- lized authority does not have the capacity or doesn`t have the complete authority to take over these new responsibilities Wang ș.a., .
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