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Acta Biologica Hungarica
Authors:
A. Smaoui
,
Jihène Jouini
,
M. Rabhi
,
G. Bouzaien
,
A. Albouchi
, and
C. Abdelly

Cotula coronopifolia is a wild annual Asteraceae that grows in periodically-flooded prone environments and seems highly tolerant to periodic flooding. Seedlings of about 15 cm were collected directly from the edge of Soliman sabkha (N-E Tunisia, semi-arid stage) and grown under greenhouse conditions. Two treatments were considered: drainage and flooding. After 56 days of treatment, flooded plants showed a pronounced growth increase. This performance was essentially associated with significant increment in biomass production of both shoots and roots (about 220% of the control). The appropriate response to flooding was also characterized by the ability of the species to maintain its water status under such conditions. Neither water content nor water potential showed a significant variation as compared to those of non-flooded plants. However, transpiration rate decreased slightly but significantly in flooded plants (from 0.86 to 0.64 mmol H2O m−2 s−1). Na+ and K+ concentrations were practically maintained under waterlogging conditions, except a significant increase of Na+ content in roots of flooded plants (157% of the control). These responses were concomitant with maintenance of photosynthetic rate. However, the contents of chlorophylls a and b increased to 167% and 295%, respectively. It seems that the enhancement in these photosynthetic pigments together with a significant improvement in water use efficiency (from 4.66 to 6.07 mmol CO2 mol−1 H2O) allowed to the species to compensate the decrease in photosynthetic rate. At the anatomical level, this species responded to flooding by a significant development of its root aerenchyma (+63%) and an increase in the lignification of its stem xylem tissues (+37%). Based on the presented data, the plant fitness under flooding conditions was a result of dynamic readjustment of several morphological, physiological, and anatomical adaptive traits. Flood requirement together with salt tolerance are responsible for the predominance of C. coronopifolia in a large area in its natural biotope where most plants cannot tolerate interactive effects of flooding and salinity.

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Abstract

Introduction

The continuous collection, monitoring, and analysis of morbidity data enable health professionals to plan the capacity of the care system, to organise and optimise care, to measure the burden of diseases resulting from each morbidity, and to estimate its expected evolution.

Material and methods

In our study, we analyse the data of patient flow reports for the period 2011 to 2020 for the healing and preventive basic service defined as the basic task of the primary health care system (troop health service) of the Hungarian Defence Forces.

Results

Over 850,000 doctor-patient encounters over the ten-year period were mostly due to some form of acute care need, infection, and respiratory illness. The morbidity structure has not changed significantly over the period. In all cases, the top three were diseases of the respiratory system (J00-J99), diseases of the circulatory system (I00-I99), as well as musculoskeletal and connective tissue diseases (M00-M99). In 2020, the highest number of people with restrictions for health reasons in the period under review was 131 for diseases of the circulatory system and 179 for musculoskeletal disorders. In recent years, the time spent on medical leave or on sick leave has increased significantly in terms of the number of cases of incapacity to work.

Conclusions

Accurate knowledge of morbidity and health data can also provide the military leadership with important information on combat fitness, especially when the ever-increasing task load (mission activity, border tasks, Covid-19) has to be met by an armed corps selected from an ageing population.

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Testing the full impact of neighbourhood crowding within natural vegetation requires more than just effects incurred by established plants. It must also include measurements that take into account suppressive effects on the earliest plant life stages of resident individuals — seeds, their germination (emergence of radicles and cotyledons), and very young rooted seedlings. In this study, we explored the potential for these effects in a field experiment spanning three years, using a novel design for controlling granivory and small mammal herbivory. This allowed us to assess the limitations of natural crowding on seed recruitment success for non-resident species introduced into both natural and denuded neighbourhood plots within a temperate mesic old field meadow in eastern Ontario, Canada. Our results show that crowding by standing vegetation of resident species caused an overall reduction of seed recruitment success by more than 90%. These data provide strong inference that suppression resulting directly from near neighbour effects are likely to impose routinely intense natural selection within temperate mesic old field habitats like our study site. The consequences of this selection, in terms of traits promoting plant fitness under competition, are traditionally interpreted in terms of superior resource depletion/uptake, typically associated with greater growth accumulation and larger potential body size. We suggest, however, that these consequences are rare. Individuals of any species approach maximum potential body size only when near neighbour effects are relatively weak — not within crowded neighbourhoods. Recent studies suggest that severe neighbourhood crowding (where virtually all resident plants are forced to remain relatively small) selects instead for ‘reproductive economy’ — i.e., capacity to produce at least a few (or even at least one) offspring despite severe body size suppression, involving a relatively small minimum reproductive threshold size. Potential for additional component traits of reproductive economy are also suggested for investigation in future research.

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After a decade of genetic manipulation and improvement, triticale stand out as a crop of high biomass and grain yield potential which generally surpass that of wheat. Its high productivity is most likely derived from high rates of carbon assimilation linked to stomatal physiology and probably low respiration rate. Being a derivative of rye, triticale has always been assumed to be relatively resistant to abiotic stress. The last review of triticale adaptation to abiotic stress as published by Jessop (1996) pointed at its general and specific fitness to harsh growing conditions. This review as based on additional data published in the last 20 years indicates that triticale retain good to excellent adaptation to conditions of limited water supply and problem soils which involve salinity, low pH, defined mineral toxicities and deficiencies and waterlogging. Despite the understandable expectations, freezing tolerance of triticale was not found to be up to the level of rye. The freezing tolerance of the rye complement in triticale is inhibited by unknown factors on the wheat parent genome. Any given triticale cultivar or selection cannot be taken a priori as being stress resistant. Research has repeatedly shown that triticale presented large genetic diversity for abiotic stress resistance and most likely this diversity has not yet been fully explored due to the very limited research and the small studied sample of the potential triticale germplasm. Triticale is a valuable stress tolerant cereal on its own accord and a potential genetic resource for breeding winter and spring cereals. Because of its high productivity and resilience it might become as important as wheat or better on a global scale if its grain technological quality will be improved to the level of wheat.

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inclusive fitness Current Biology 23 R577 R584 . A. Zahavi 1975 Mate selection — a

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. Fresenius Z. Anal. Chem. 1956 149 46 66 EURACHEM Guide, Fitness for analytical methods — English

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J. Theor. Biol 180 27 37 Taylor, P. D. (1996): Inclusive fitness arguments in genetic models of

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21 Blair SN, Kohl HW, Paffenbarger RS, Clark DG, Cooper KH, Gibbons LW: Physical fitness and all-cause mortality: a prospective study of healthy men and women. JAMA 262, 2395–2401 (1989

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Silver is used extensively in both hospitals and outpatient clinics as a disinfectant coating agent on various devices. Resistance to silver was recently reported as an emerging problem in Enterobacteriaceae. Multidrug-resistant high-risk clones of Klebsiella pneumoniae are common causes of serious healthcare-associated infections worldwide posing a serious threat to patients. In this study, we investigated the capacity of both high-risk (CG14/15 and CG258) and minor clone strains of K. pneumoniae to develop resistance to silver. Resistance was induced in vitro in silver-susceptible but otherwise multidrug-resistant clinical isolates. Genetic alterations in the silver-resistant derivative strains with regard to the silver-susceptible isolates were investigated by whole-genome sequencing. The transferability of high-level resistance to silver was also tested. We demonstrated that the high-level resistance to silver can quickly evolve as a consequence of a single-point mutation either in the cusS gene of the chromosomally encoded CusCFBARS efflux system and/or in the silS gene of the plasmid-encoded Copper Homeostasis and Silver Resistance Island (CHASRI) coding also for a metallic efflux. The minimal inhibitory concentrations (MICs) of the strains increased from 4 mg/L (23.5 μM) AgNO3 to >8,500 mg/L (>50,000 μM) AgNO3 during induction. Harboring the CHASRI proved an important selective asset for K. pneumoniae when exposed to silver. Successful conjugation experiments using Escherichia coli K12 J5-3Rif as recipient showed that high-level silver resistance can transmit between strains of high-risk clones of K. pneumoniae (ST15 and ST11) and isolates from additional species of Enterobacteriaceae. The lack of fitness cost associated with the carriage of the CHASRI in a silver-free environment and the presence of the RelEB toxin–antitoxin system on the conjugative plasmids could advance the dissemination of silver resistance. Our results show that multidrug-resistant high-risk clones of K. pneumoniae are capable of evolving and transmitting high-level resistance to silver. This observation should warrant a more judicious use of silver coated-devices to prevent the extensive dissemination of silver resistance.

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Sportolás elektronikus monitorozással időskorban

Athletic fitness development with electronic monitoring in older adult

Orvosi Hetilap
Authors:
E. Andrew Balas
,
Tímea Kováts
,
Rita Mikulán
,
Béla Székács
,
László Török
, and
Balázs Kollai

Összefoglaló. Idősebb korban a testgyakorlás különösen fontos az izmok sorvadásának megelőzése, valamint a vérnyomás és a testsúly kontrollja céljából. Ma már egyre gyakoribb az időskorúak részvétele sportversenyeken is. Esettanulmányunk célja a késő felnőttkori, illetve időskori versenyszerű sportolás egészségi alkalmassági feltételeinek, kockázatainak és a teljesítőképesség változásainak bemutatása az elektronikus monitorozás és virtuális versenyzés korában. Esetünkben ez egy időskorú személy 16 év során (54–70 éves kor) teljesített maratoni futóversenyeinek, valamint virtuális evezőversenyek részvételi és felkészülési adatainak elemzésével valósul meg. Esetünk illusztrálja, hogy az észszerű túlterhelés elve alapján az izmok adaptációja akkor következik be, amikor az edzés terhelése meghaladja az addig már elért terhelési szintet. A sportóra használata az elektronikus pulzusszám és a teljesítmény monitorozásával nemcsak a versenyek és edzések alatt a pulzusszám céltartományban tartására, de hosszabb távú tendenciák felismerésére is hasznosnak bizonyult. Az egészségi állapotnak megfelelő (sportág és intenzitás) időskori testgyakorlás és sportversenyen való részvétel nemcsak az erőnlét megtartását tűzheti ki célul, hanem értékes erőnlétfejlesztést is. Orv Hetil. 2021; 162(51): 2061–2066.

Summary. With advancing age, exercise becomes particularly important to prevent muscle atrophy and to control blood pressure and weight. Today, participation of aging people in athletic competitions is increasingly common. The aim of our case study is to explore and illustrate the health conditions, development and risk factors of competitive sporting activities of late adult and elderly athletes in the age of electronic monitoring and virtual racing. We processed the preparation and participation data of a total of 16 years of marathon races as well as rowing machine races of an elderly male person (age 54–70). Using a sports watch with electronic heart rate and performance monitoring has proved useful not only for keeping the heart rate in target range, but also for assessing trends in the long run. Our case underscores the value of reasonable overload with advancing age; beneficial muscle adaptation occurs when the workload of an exercise exceeds the previously reached level. Gradual exercise of older adults and participation in athletic competitions can not only maintain fitness but also develop valuable additional strength. Orv Hetil. 2021; 162(51): 2061–2066.

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