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Determining the genetic characteristics of natural fish stocks is useful for conservation and aquaculture programs. For African catfish, Clarias gariepinus, genetic characterization could help identify populations suitable as brood stock for culture, and those in need of conservation. This study determined the genetic diversity, population structure, and demographic history of C. gariepinus from Lakes Victoria (LV), Kenyatta (LKE), Kamnarok (LKA), and Rivers Nyando (NR), Tana (TR) and Sosiani (SR) in Kenya. Using 128 DNA sequences of D-loop control region, 34 haplotypes were recovered, of which 79.4% were singletons. Only 7 haplotypes were shared between sites, implying little gene flow between sites. Number of haplotypes was highest in LKE and NR populations and lowest in SR. Haplotype diversity was highest in LV, and lowest in SR, while, nucleotide diversity was highest in LKA and lowest in LV. Phylogenetic analyses revealed five clusters: Lakes Victoria, Kamnarok and Kenyatta, and Rivers Tana and Nyando, from both maximum likelihood tree and minimum spanning network. This, together with significant F ST values among the sites imply population differentiation. Mismatch distributions were multi-modal in LKA, LKE, NR and TR, signifying demographic equilibria. Neutrality tests Tajima`s D values for the sampled populations were negative and significantly different, suggesting stable populations. These results show the existence of genetically distinct populations of C. gariepinus that require spatially explicit management actions such as reducing fishing pressure, pollution, minimizing habitat destruction and fragmentation for sustainable utilisation of stocks.  相似文献   
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The coastal forests of Kenya are conservation priorities hosting high levels of biodiversity. Monitoring of biodiversity in these forests is therefore necessary to understand and reverse negative trends in good time. Using the Important Bird Area (IBA) monitoring framework, a participatory approach, state (habitat condition), pressure (threats) and response (conservation action) indicators of twelve coastal Kenya forest IBAs were assessed from 2004 to 2011. Trends for these indicators were assessed at six sites for which sufficient data existed: Arabuko‐Sokoke, Dakatcha Woodlands, Gede Ruins, Lower Tana River, Shimba Hills and Taita Hills, and baselines were described for remaining six. Changes were always small, but state deteriorated in Gede, Lower Tana and Shimba Hills, remained the same (unfavourable) in Arabuko‐Sokoke and Dakatcha, and improved in Taita Hills. Pressure reduced in Arabuko‐Sokoke, Dakatcha and Taita Hills, deteriorated in Lower Tana and Shimba Hills and remained the same (medium) in Gede. Response improved in Dakatcha, remained the same (medium) in Shimba Hills, and deteriorated in the rest. As there was an apparent overall deterioration in the forests assessed, improved management of the protected sites and increased conservation action through community engagement around protected areas and within the nonprotected IBAs are recommended.  相似文献   
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BackgroundViolence against women and girls (VAWG) is a human rights violation with social, economic, and health consequences for survivors, perpetrators, and society. Robust evidence on economic, social, and health impact, plus the cost of delivery of VAWG prevention, is critical to making the case for investment, particularly in low- and middle-income countries (LMICs) where health sector resources are highly constrained. We report on the costs and health impact of VAWG prevention in 6 countries.Methods and findingsWe conducted a trial-based cost-effectiveness analysis of VAWG prevention interventions using primary data from 5 randomised controlled trials (RCTs) in sub-Saharan Africa and 1 in South Asia. We evaluated 2 school-based interventions aimed at adolescents (11 to 14 years old) and 2 workshop-based (small group or one to one) interventions, 1 community-based intervention, and 1 combined small group and community-based programme all aimed at adult men and women (18+ years old). All interventions were delivered between 2015 and 2018 and were compared to a do-nothing scenario, except for one of the school-based interventions (government-mandated programme) and for the combined intervention (access to financial services in small groups). We computed the health burden from VAWG with disability-adjusted life year (DALY). We estimated per capita DALYs averted using statistical models that reflect each trial’s design and any baseline imbalances. We report cost-effectiveness as cost per DALY averted and characterise uncertainty in the estimates with probabilistic sensitivity analysis (PSA) and cost-effectiveness acceptability curves (CEACs), which show the probability of cost-effectiveness at different thresholds. We report a subgroup analysis of the small group component of the combined intervention and no other subgroup analysis. We also report an impact inventory to illustrate interventions’ socioeconomic impact beyond health. We use a 3% discount rate for investment costs and a 1-year time horizon, assuming no effects post the intervention period. From a health sector perspective, the cost per DALY averted varies between US$222 (2018), for an established gender attitudes and harmful social norms change community-based intervention in Ghana, to US$17,548 (2018) for a livelihoods intervention in South Africa. Taking a societal perspective and including wider economic impact improves the cost-effectiveness of some interventions but reduces others. For example, interventions with positive economic impacts, often those with explicit economic goals, offset implementation costs and achieve more favourable cost-effectiveness ratios. Results are robust to sensitivity analyses. Our DALYs include a subset of the health consequences of VAWG exposure; we assume no mortality impact from any of the health consequences included in the DALYs calculations. In both cases, we may be underestimating overall health impact. We also do not report on participants’ health costs.ConclusionsWe demonstrate that investment in established community-based VAWG prevention interventions can improve population health in LMICs, even within highly constrained health budgets. However, several VAWG prevention interventions require further modification to achieve affordability and cost-effectiveness at scale. Broadening the range of social, health, and economic outcomes captured in future cost-effectiveness assessments remains critical to justifying the investment urgently required to prevent VAWG globally.

In a cost-effectiveness study, Dr. Giulia Ferrari and colleagues examine the costs and health impact of prevention of violence against women and girls in six low- and middle-income countries.  相似文献   
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Summary Chick embryo heart fragments in primary hanging-drop culture were treated with sodium fluoroacetate to induce inhibition of aconitate hydratase, a mitochondrial enzyme of the tricarboxylic acid cycle. The mitochondria were analyzed in the living myoblasts by phase-contrast time-lapse cinemicrography. The results were recorded in a 16 mm film. After 20–30 minutes contact of the cells with the inhibitor some mitochondria became thickened and swollen. The swelling was polymorphous, asynchronous and reversible; the same mitochondrion could swell and shrink many times. Some mitochondria seemed not to respond to fluoroacetate and remained rod-like. Mitochondria appeared the only cell components to be morphologically affected by fluoroacetate and the changes were specifically caused by the inhibitor. The type of mitochondrial swelling differed from the large-amplitude respiration-dependent swelling of the isolated mitochondria in vitro and from the configurational changes of isolated mitochondria associated with the respiratory states. The evidence pointed to a specific connection between the biochemical lesion caused by fluoroacetate and the configurational changes of the mitochondria. The mitochondrial swelling was to a large extent reversed by washing the cultures with Tyrode physiological saline solution and the reversal was further accentuated by incubation of the cultures in fresh nutrient medium.This work was supported by grants of the Consiglio Nazionale delle Richerce of Italy to both Institutes.  相似文献   
6.
Zusammenfassung Die Wachstums- und Umbauvorgänge am Knochen des Hornfortsatzes vom männlichen und weiblichen Steinbock (Capra ibex) wurden histologisch untersucht.Der Hornfortsatz des Männchens erreicht eine weit erheblichere Größe als der des weiblichen Tieres. Bei dem Bock beginnt das Wachstum des Fortsatzes früher, ist quantitativ intensiver und dauert während des ganzen Lebens fort, während es beim Weibchen im vierten Lebensjahr aufhört.Die Zunahme an Dicke und Länge erfolgt durch die appositionelle Tätigkeit des Periostes. Das Dickenwachstum vollzieht sich ebenso wie bei der periostalen Ossifikation der Röhrenknochen. Jedoch ist die Knochensubstanz, die sich in den verschiedenen Altersstufen bildet, verschieden. Bei jungen Tieren lagern sich Bälkchen von geflechtartigem und parallelfaserigem Knochen ab, beim erwachsenen Steinbock kompakte Schichten von parallelfaserigem Knochen. Der primäre Periostalknochen wird später zu einer kompakten Schicht von sekundärem Osteonknochen umgebaut. Der Umbau schreitet von den tiefen, der Höhlung zugewandten Teilen zur Oberfläche hin fort. Der Ersatz beginnt in den proximalen Abschnitten des Hornfortsatzes und setzt sich distalwärts fort. Der Hornfortsatz nimmt schließlich die Struktur der Substantia compacta eines Röhrenknochens an, obgleich er, im Gegensatz zu den Röhrenknochen, keinerlei Muskeleinwirkung ausgesetzt ist. Das Längenwachstum beruht auf der fortschreitenden Ablagerung von neuem, primärem Bälkchenmaterial in der Spitzengegend. Dieses Gewebe erfährt später das gleiche Schicksal wie jenes, das sich früher in den proximalen Teilen gebildet hatte.Die Wachstums- und Umbauvorgänge der Knochensubstanz sind bei beiden Geschlechtern gleichartig. Die verschiedene Größe des Hornfortsatzes von Männchen und Weibchen beruht auf quantitativen, nicht auf qualitativen Unterschieden der Knochenbildung. Innere Umbauprozesse dagegen spielen sich bei beiden Geschlechtern während des ganzen Lebens lebhaft ab. Beim Weibchen erfolgt der Ersatz des primären Periostalknochens durch sekundären Osteonknochen im Zusammenhang mit dem begrenzten appositionellen Wachstum schneller und ausgedehnter.Vergleicht man gleichaltrige Tiere, so stellt man beim Weibchen einen stärkeren Umbau des Sekundärmaterials fest; auch ist dessen Struktur komplexer. Dies hängt mit der Tatsache zusammen, daß sich die Umbauvorgänge an einem Material abspielen, das längere Zeit in situ bleibt.Unter den Faktoren, die zu einem erhöhten Umbau der Knochensubstanz, einem gewissen Überwiegen von interstitiellen Abbauerscheinungen und einer größeren strukturellen Heterogenität im Hornfortsatze des Weibchens führen, werden außer der Begrenzung des appositionellen Wachstums auch die geringere funktionelle Aktivität und das Vorkommen von Trächtigkeits- und Säugeperioden in Betracht gezogen.Außerdem wird durch die vorliegenden Untersuchungen bestätigt, was schon für anderes Material angenommen wurde, daß nämlich die aktuellen mechanischen Momente in den Umbauprozessen der osteonischen Strukturen nicht die wichtigste Rolle spielen.

Parco Nazionale del Gran Paradiso: contributo scientifico N° 22.  相似文献   
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Riassunto Furono istituiti confronti, in preparati col metodo Golgi-Cox, tra i caratteri dei neuroni piramidali grandi, medi e piccoli della corteccia cerebrale di Mammiferi di grandezza somatica molto differente, e piú precisamente: cavallo, bue, uomo, scrofa, pecora, capra, cane, gatto, coniglio, cavia, ratto, topo. Nell'uomo fu scelto il campo 4 di Brodmann; negli animali una regione della corteccia presumibilmente corrispondente.Nello stesso materiale fu determinata, in preparati col metodo Nissl, la densità dei neuroni, in modo da poter stabilire il numero dei neuroni per mm3 di corteccia.Furono riscontrate differenze modeste nella grandezza del pericario nei vari animali, incomparabilmente meno accentuate di quelle esistenti nello stesso materiale per i neuroni sprovvisti di dendriti (gangli sensitivi). Sono invece imponenti le differenze nell'estensione dell'arborizzazione dendritica. Tali differenze sono di più alto grado nelle grandi cellule piramidali che nelle medie e nelle piccole; però sono ben evidenti anche in queste ultime.Tra i valori ottenuti nella densità dei neuroni e quanto risulta nei preparati col metodo Golgi sull'estensione dell'arborizzazione dendritica negli animali di grandezza corporea differente, vi è coincidenza nel senso che, quanto più ampio è lo spazio occupato dall'arborizzazione dendritica dei neuroni della corteccia e quanto più numerosi sono i neuriti afferenti e le loro collaterali, tanto minore è la densità dei neuroni.I risultati delle presenti osservazioni si accordano con i recenti reperti col microscopic elettronico, secondo i quali i neuroni, la glia ed i vasi sanguiferi sono fittamente stipati, al punto che le fessure, le quali li separano, sono dell'ordine di grandezza submicroscopica; non esistono, nei centri nervosi, altri componenti al di fuori dei neuroni, della glia e dei vasi.Dedicato al Prof. Giuseppe Levi per il suo 88 compleanno. Ricerche compiute con un contributo del C.N.R.  相似文献   
9.

Background

Public primary health care (PHC) facilities are for many individuals the first point of contact with the formal health care system. These facilities are managed by professional nurses or clinical officers who are recognised to play a key role in implementing health sector reforms and facilitating initiatives aimed at strengthening community involvement. Little in-depth research exists about the dimensions and challenges of these managers’ jobs, or on the impact of decentralisation on their roles and responsibilities. In this paper, we describe the roles and responsibilities of PHC managers–or ‘in-charges’ in Kenya, and their challenges and coping strategies, under accelerated devolution.

Methods

The data presented in this paper is part of a wider set of activities aimed at understanding governance changes under devolution in Kenya, under the umbrella of a ‘learning site’. A learning site is a long term process of collaboration between health managers and researchers deciding together on key health system questions and interventions. Data were collected through seven formal in depth interviews and observations at four PHC facilities as well as eight in depth interviews and informal interactions with sub-county managers from June 2013 to July 2014. Drawing on the Aragon framework of organisation capacity we discuss the multiple accountabilities, daily routines, challenges and coping strategies among PHC facility managers.

Results

PHC in-charges perform complex and diverse roles in a difficult environment with relatively little formal preparation. Their key concerns are lack of job clarity and preparedness, the difficulty of balancing multidirectional accountability responsibilities amidst significant resource shortages, and remuneration anxieties. We show that day-to-day management in an environment of resource constraints and uncertainty requires PHC in-charges who are resilient, reflective, and continuously able to learn and adapt. We highlight the importance of leadership development including the building of critical soft skills such as relationship building.  相似文献   
10.
Approximately 850 bp of the mitochondrial control region was used to assess the genetic diversity, population structure and demographic expansion of the endangered cyprinid Barbus altianalis, a species known to be potamodramous in the Lake Victoria drainage system. The 196 samples taken from the four main rivers draining the Lake Victoria catchment (Nzoia, Yala, Nyando and Sondu–Miriu) yielded 49 mitochondrial DNA haplotypes; 83.7% thereof were private haplotypes restricted to particular rivers. The overall mean haplotype diversity was high (0.93663 ± 0.008) and ranged between 0.566 (Sondu – Miriu) and 0.944 (Nzoia). The overall mean nucleotide diversity was low (0.01322 ± 0.00141), ranging from 0.0342 (Sondu – Miriu) to 0.0267 (Nzoia). Population differentiation tests revealed strong and highly significant (P ≤ 0.001) segregation of populations in the four river basins. FST values among the four river‐based populations ranged from 0.05202 to 0.44352. The samples formed two main haplotype networks based on a 95% parsimony criterion, each exhibiting a strong signature of past population expansion. The smaller network was restricted to the River Nzoia, whereas the larger network contained representatives from all four rivers; within this the central haplotypes were found in more than one river, whereas the peripheral haplotypes tended to be river‐specific. The degree of population differentiation and the number of river‐specific haplotypes are too high to be explained by recent anthropogenic impacts alone and suggest that the species has probably existed in the Lake Victoria catchment as two populations: the now ‘extinct’ migratory population and the extant river restricted non‐migratory populations.  相似文献   
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