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As an evolutionary lineage cycads are rare, and the extinction risk is high for many species. The genus Ceratozamia, one of the most diverse in Mexico, is experiencing drastic reductions of its habitat. Ceratozamia is widely distributed along the Sierra Madre Oriental, a complex mountain range, in a region characterized by high ecological and cultural diversity. Since 1990, various conservation and management strategies have been applied to this taxon in Mexico but evidence for the effectiveness of these measures is lacking. Ceratozamia in the Mexican Sierra Madre Oriental is highly diverse and endemic, offering a model for analysing geographical distribution patterns with ecological niche modelling. It also presents an opportunity for assessing the success of conservation and management strategies that have been implemented in this area. Here, we examined three aspects that are considered fundamental for the development and evaluation of conservation strategies: (1) taxonomy, (2) ecology and (3) sociocultural anthropology. Our findings suggest a pessimistic outlook for the long-term survival of Ceratozamia species in their natural environment, indicating the need to review the current IUCN Cycad Action Plan for the genus. To improve the protection of Ceratozamia and other taxonomic and/or ecological assemblages, we encourage a multidisciplinary approach, with increased collaboration between natural and social scientists.
We aimed at evaluating the association of maternal pre-pregnancy nutritional status with offspring anthropometry and body composition. We also evaluated whether these associations were modified by gender, diet and physical activity and mediated by birth weight.
Design:
Birth cohort study.
Setting:
Waist circumference was measured with an inextensible tape, and fat and lean mass were measured using dual-energy X-ray absorptiometry. Multiple linear regression was used to adjust for possible confounders and allele score of BMI. We carried out mediation analysis using G-formula.
Participants:
In 1982, 1993 and 2004, all maternity hospitals in Pelotas (South Brazil) were visited daily and all live births whose families lived in the urban area of the city were evaluated. These subjects have been followed up at different ages.
Results:
Offspring of obese mothers had on average higher BMI, waist circumference and fat mass index than those of normal weight mothers, and these differences were higher among daughters. The magnitudes of the association were similar in the cohorts, except for height, where the association pattern was not clear. In the 1982 cohort, further adjustment for a BMI allele score had no material influence on the magnitude of the associations. Mediation analyses showed that birth weight captured part of this association.
Conclusions:
Our findings suggest that maternal pre-pregnancy nutritional status is positively associated with offspring BMI and adiposity in offspring. And this association is higher among daughters whose mother was overweight or obese and, birth weight explains part of this association.
Background:
Improving adherence to hand hygiene (HH) of healthcare workers (HCWs) is a challenge for health institutions, and the use of technologies has been considered an important strategy within this process. Methods: To evaluate the impact of the use of alcohol-based hand rub gel (ABHR) dispensers with light sensors on the adherence to HH by HCWs. This is a prospective quasi-experimental study with comparative analysis between two 4-bed adult intensive care units at a private, tertiary-care hospital conducted over 22 weeks. An approach detection module with an LED lamp was attached to the ABHR dispenser. As a healthcare personnel approached it, the sensor was activated, and a red light turned on as a visual stimulus for HH. The color of the light changed to blue when HH was performed. All ABHR dispensers had electronic counters, but light sensors were installed only in the 4-bed dispensers of the intervention unit. Throughout the period, direct observation of adherence to HH was performed by 4 nurses who had previously been rated with an excellent coefficient of agreement (κ test = 0.951 and 0.902). At the end of the study, a perception survey was performed with the HCWs. Results: The median activation of ABHR dispensers per week was higher in the intervention unit with 1,004 (IQR, 706–1,455) versus 432 (IQR, 350–587) in the control group (P < .001). The same occurred when compared to the median activation per 1,000 patient days, with 53,069 (IQR, 47,575–67,275) versus 19,602 (IQR, 15,909–24,500) in the control group (P < .001). However, there was no evidence of difference in adherence to HH during direct observation between the 2 groups: 51.0% HH compliance (359 of 704) in the control group and 53.8% HH compliance (292 of 543) in the intervention group (P = .330). The same result emerged when we evaluated the “My Five Moments for HH” and by professional category. HCWs (N=66) answered the perception survey: 66.6% stated that lighting devices caught their attention regularly or most of the time and 59% agreed that the devices motivated HH. Conclusions: Using light sensors in ABHR dispensers can be an effective technology for improving HH. This finding was evident in the evaluation of the number of uses of the ABHR dispensers and in the HCW perceptions. Although direct observation did not show statistical evidence of difference between the groups, adherence was higher in the intervention group.
Background: The ventriculoperitoneal shunt is the main procedure used for to treat communicating hydrocephalus. Surgical site infection associated with the shunt device is the most common complication and a cause of morbidity and mortality of related to the treatment. We sought to answer 3 questions: (1) What is the risk of meningitis after ventricular shunt operations? (2) What are the risk factors for meningitis? (3) What are the main microorganisms causing meningitis? Methods: We conducted a retrospective cohort study of patients undergoing ventricular shunt operations between July 2015 and June 2018 from 12 hospitals at Belo Horizonte, Brazil. Data were gathered by standardized methods defined by the CDC NHSN. Our sample size was 926, and we evaluated 26 preoperative and operative variables by univariate and multivariate analysis. Our outcome variables of interest were meningitis and hospital death. Results: In total, 71 cases of meningitis were diagnosed (risk, 7.7%; 95% CI, 6.1%–9.6%). The mortality rate among patients without infection was 10%, whereas hospital mortality of infected patients was 13% (P = .544). The 3 main risk factors for meningitis after ventricular shunt were identified by logistic regression model: age <2 years (OR, 3.20; P < .001), preoperative hospital stay >4 days (OR, 2.02; P = .007) and >1 surgical procedure, in addition to ventricular shunt (OR, 3.23; P = .043). Almost 1 of 3 of all patients was <2 years old (290, 31%). Also, 430 patients had >4 preoperative days (46%). Patients aged ≥2 years who underwent surgery 4 days after hospital admission had an increased risk of meningitis, from 4% to 6% (P = .140). If a patient <2 years old underwent surgery 4 or more days after hospital admission, the risk of meningitis increased from 9% to 18% (P = .026; Fig. 1). We built a risk index using the number of main risk factors based on a logistic regression model (0, 1, 2 or 3; Fig. 2). Conclusions:We identified 2 intrinsic risk factors for meningitis after ventricular shunt, age <2 years and multiple surgical procedures, and 1 extrinsic risk factor, the preoperative length of hospital stay.
Human visceral leishmaniasis (HVL) cases are important public health problems due to their zoonotic aspect, with high rates of morbidity and mortality in Brazil. The aim of this this study was to identify spatial patterns in both rates of HVL cases in Brazilian states during the period from 2006 to 2015. This is an ecological study, using geoprocessing tools to create choropleth maps, based on secondary data from open access platforms, to identify priority areas for control actions of the disease. Data were collected in 2017 and analysed according to the global and local Moran's I, using TerraView 4.2.2 software. Similar clusters were observed in neighbouring municipalities in thematic maps of HVL, suggesting spatial similarity in the distribution of the disease in humans mainly in the North and Northeast Regions, which concentrate the states with the highest rates of HVL. Heterogeneous spatial patterns were observed in the distribution of HVL, which show municipalities that need higher priority in the intensification of disease surveillance and control strategies.
Direct numerical simulations (DNS) of spatially evolving turbulent planar jets of viscoelastic fluids described by the FENE-P model, such as those consisting of a Newtonian fluid solvent carrying long chain polymer molecules, are carried out in order to develop a theory for the far field of turbulent jets of viscoelastic fluids. New evolution relations for the jet shear-layer thickness
$\unicode[STIX]{x1D6FF}(x)$
, centreline velocity
$U_{c}(x)$
and maximum polymer stresses
$\unicode[STIX]{x1D70E}_{c}^{[p]}(x)$
are derived and validated by the new DNS data, yielding
$\unicode[STIX]{x1D6FF}(x)\sim x$
,
$U_{c}(x)\sim x^{-1/2}$
, and
$\unicode[STIX]{x1D70E}_{c}^{[p]}(x)\sim x^{-5/2}$
, respectively, where
$x$
is the coordinate in the streamwise direction. It is shown that, compared with a classical (Newtonian) turbulent jet, the effect of the polymers is to reduce the spreading rate, centreline velocity decay, Reynolds stresses and viscous dissipation rate. The self-preserving character of the flow is analysed and it is shown that profiles of mean velocity, Reynolds stresses and polymer stresses are self-similar provided the proper scales are used in the normalisation of these quantities. A fundamental difference from the Newtonian jet in this regard is the necessity for two, instead of only one, different velocity and length scales to properly characterise the evolution of the turbulent flow. These extra velocity and length scales are directly related to a time scale associated with the characteristic fading memory property of viscoelastic fluids.
Relay intercropping of maize with fodder crops is a promising option for sustainable intensification of dairy small-scale farms in the Cerrado of Brazil. Twenty-six intercropping trials were conducted on farmers’ fields with the following experimental treatments: sole maize crop cropping (MS), maize-Brachiaria intercropping (MB) and maize-pigeon pea intercropping (MP). The trials were managed by the farmers, i.e. choice of conventional tillage (CT) versus no-tillage (NT), sowing dates, fertilization and weed control. Maize grain yield varied strongly across the farmer fields, from 100 to 5900 kg ha−1 in the MS treatment, 500 to 6900 kg ha−1 in MP and 300 to 5500 kg ha−1 in MB. Intercropping did not significantly affect maize grain yields under NT, but yields were reduced under CT in one out of two seasons. Maize yields in the intercropped systems were also higher under NT than CT. Total biomass productivity was significantly higher in the maize-fodder than in the sole maize system. An increased interval between sowing of maize and fodder crop significantly reduced the fodder crop biomass. Relay intercropping, especially in combination with NT, is a promising option if crop calendars and fertilization are properly managed by farmers to reduce interspecific competition between the maize and fodder crop.
The whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is one of the most important agricultural pests and virus vectors worldwide. Bemisia tabaci is considered a complex of cryptic species with at least 44 species. Among them, the species Middle East-Asia Minor 1 (MEAM1, formerly B biotype) and Mediterranean (MED, formerly Q biotype) are the most important, and they have attained global status. In Brazil, MEAM1 was first reported in the 1990s and is currently the predominant species in the country, meanwhile, MED was recently reported in the South and Southeast regions and was found to be mainly associated with ornamental plants. Currently, an increasing problem in the management of whitefly infestations in greenhouses associated with bell pepper was observed in São Paulo State, Brazil. The whiteflies were collected and identified based on a microsatellite locus (primer pair BEM23F and BEM23R) and the mitochondrial cytochrome oxidase I gene followed by restriction fragment length polymorphism analysis and sequencing. We observed that MED was the predominant species collected on bell pepper, but it was also found on tomato, cucumber, eggplant, and weeds grown in greenhouses. In open field, we found MED on tomatoes, bell peppers, and eggplants. In addition, MED was identified in Goiás State in association with ornamental plants. The begomovirus Tomato severe rugose virus and the crinivirus Tomato chlorosis virus was detected on bell pepper and tomato, respectively. Only MED specimens were found associated with the virus-infected plants. Moreover, we also investigated the endosymbionts present in the MED whiteflies. The collected populations of B. tabaci MED harbored a diversity of secondary endosymbionts, with Hamiltonella (H) found predominantly in 89 specimens of the 129 tested. These results represent a new concern for Brazilian agriculture, especially for the management of the newly introduced whitefly MED species, which must be implemented to limit the spreading and establishment of this pest in different crops in this country.
The objective of this work was to evaluate the effect of protein reduction, with or without the supplementation of limiting amino acids, on the performance and carcass characteristics of meat quails from 22 to 42 days of age in a thermoneutral environment. A total of 324 European quails were randomly allocated into nine diets. The diets were formulated based on the recommended requirement (control) and were differentiated according to crude protein (CP) reduction levels into moderate reduction (10%) and severe reduction (20%). The diets were supplemented or not with limiting amino acids. The diets with severe and moderate protein reduction meeting the methionine + cystine, lysine and threonine requirements led to weight gain equivalent to that of the control quails. The diet with a moderate reduction in CP, with or without meeting the methionine + cystine requirement or meeting the methionine + cystine and lysine requirement, led to the greatest carcass yield and a greater leg weight and were similar to the control treatment. It is observed that supplementation with the crystalline sources of the amino acids is able to improve the performance of the quails, in addition, the attendance of methionine + cystine requirement important factor when the CP levels are reduced. In our studies, diets with 17.5% CP and supplemented with methionine + cystine, lysine and threonine meet the requirements of quails, thus generating a limiting amino acid requirement, so they are recommended for meat quails from 22 to 42 days old housed in thermoneutral environment.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
The University of São Paulo Twin Panel (Painel USP de Gêmeos), based at the Institute of Psychology of the University of São Paulo, started formally in 2017. Our registry is new, but in only two years of formal existence, it comprises a volunteer sample of 4826 registered individuals (98% twins and 2% higher-order multiples), recruited at the University of São Paulo and by social media campaigns. Our main aim is to conduct and promote research with twins on psychological processes and behavior. The University of São Paulo is the largest higher education and research institution in South America, and the Painel USP de Gêmeos has great potential for fostering research on twin-related issues from a psychological perspective in Brazil and South America.
Studies integrating variation in species composition among sites are useful in understanding the impacts of land-use changes on the spatial distribution of biodiversity. However, the failure to recognize the distinction between beta diversity components, dissimilarity due to species replacement (i.e. turnover) and dissimilarity due to species loss from site to site (i.e. nestedness), can lead to inappropriate use of some indices. Here, we evaluated how the spatial distribution of anuran beta diversity components, turnover and nestedness, is associated with local and landscape descriptors in a tropical agricultural landscape with a recent history of agriculture expansion in south-eastern Brazil. Overall, 27 anuran species were found in the region with average ± SD species richness in each pool of 9.5 ± 3.5 species, ranging from 4 to 15 species. We observed that species turnover was the major component for anuran dissimilarity among pools, indicating that anuran species occurring in species-poor pools are not subsets of anuran species occurring in species-rich pools. Local variables and geographic distance were not important descriptors explaining the variation of anuran beta diversity. In contrast, the distance of the pools to the nearest forest fragment explained 16% of the variance in total beta diversity, 5% of the nestedness component and 2% of spatial turnover. Our results show that pools distributed across farmland landscapes are harbouring different anuran species composition, and together, these pools are contributing to the regional diversity of anurans in this region which is considered one of the most deforested and fragmented within Brazil.
The Endangered Asian elephant Elephas maximus comes into widespread conflict with agrarian communities, necessitating active management. The species’ distribution is of primary importance for management planning. However, data-based countrywide distribution maps have not been available for any of the 13 Asian elephant range states. We conducted a 5 × 5 km grid-based questionnaire survey in Sri Lanka to produce an island-wide elephant distribution map. Elephants occur over 59.9% of Sri Lanka and people are resident in 69.4% of elephant range, indicating the challenge of separating people and elephants at a landscape scale. Elephants in Sri Lanka have lost 16.1% of their range since 1960 but their current distribution remains largely contiguous. We found the range of adult males was 15.1% greater, and less seasonal, than that of herds, possibly because males have a higher tolerance for conflict with people. The distribution of conflict coincided with the co-occurrence of humans and elephants. We conclude that a human–elephant coexistence model is the only viable option for effectively mitigating human–elephant conflict and conserving elephants in Sri Lanka. The findings are currently being used to effect a paradigm change in elephant conservation and management in the country.
Graded exercises tests are performed in adult populations; nonetheless, the use of this type of assessment is greatly understudied in overweight and obese adolescents.
Objective
To investigate heart rate autonomic responses to submaximal aerobic exercise in obese and overweight adolescents.
Methods
We recruited 40 adolescents divided into two groups: (1) overweight group comprising 10 boys and 10 girls between Z-score +1 and +2 and (2) obese group comprising 10 boys and 10 girls above Z-score >+2. Heart rate variability was analysed before (T1) and after exercise (T2–T4) on treadmill at a slope of 0%, with 70% of the maximal estimated heart rate (220 – age) for 20 minutes.
Results
Heart rate in the overweight group was: 93.2±10.52 bpm versus 120.8±13.49 bpm versus 94.6±11.65 bpm versus 93.0±9.23 bpm, and in the obese group was: 92.0±15.41 bpm versus 117.6±16.31 bpm versus 92.1±12.9 bpm versus 91.8±14.33 bpm. High frequency in the overweight group was: 640±633.1 ms2 versus 84±174.66 ms2 versus 603.5±655.31 ms2 versus 762.6±807.21 ms2, and in the obese group was: 628.4±779.81 ms2 versus 65.4±119.34 ms2 versus 506.2±482.70 ms2 versus 677.9±939.05 ms2; and root mean square of successive differences in the overweight group was: 37.9±18.81 ms versus 10.9±8.41 ms versus 32.8±24.07 ms versus 36.7±21.86 ms, and in the obese group was: 38.7±23.17 ms versus 11.5±8.62 ms versus 32.3±16.74 ms versus 37.3±24.21 ms. These values significantly changed during exercise compared with resting values in overweight and obese groups. Moreover, we also reported no significant difference of resting parasympathetic control of heart rate between obese and overweight adolescents.
Conclusion
There was no significant difference of autonomic responses elicited by submaximal aerobic exercise between overweight and obese adolescents.
This study aimed to calculate economic values (EVs) and economic selection indices for milk production systems in small rural properties. The traits 305-d milk yield in kg (MY), fat (FP) and protein (PP) percentage, daily fat (FY) and protein (PY) yield, cow live weight in kg (LW), calving interval (CI), and logarithm of daily somatic cell count (SCC) in milk were considered the goals and selection criteria. The production systems were identified from 29 commercial properties based on the inventory of revenues and costs and of zootechnical field data. Later, bioeconomic models were developed to calculate the productive performance, revenues, and costs concerning milk production to estimate EVs, which were calculated as the difference in annual profit with dairy production resulting from a change in one unit of the trait while keeping the others constant and dividing the value by the number of cows. After the EVs were known, ten economic selection indices were estimated for each system so they could be compared by modifying the selection criteria and calculating the relative importance of each selection criteria, the accuracy of the economic selection index, and response expected to the selection in USD, among other parameters. One of the systems detected was called less intensive (LS) and was characterized by having ten cows in lactation that produced 13·5 l/d and consumed 1·8 kg of concentrate/d. The second system detected was called more intensive (IS) and had 22 cows in lactation that produced 17·5 l/d and consumed 3·4 kg of concentrate/d. Monthly profits per cows in lactation of USD 2·60 and USD 68·77 were recorded for LS and IS, respectively. The EVs of the traits MY, FP, and PP were all positive, while for the other traits they were all negative in all situations. The best economic selection indices were those featuring selection criteria MY, LW, and CI, while the trait LW had the greatest importance in both systems. These results indicate that animal frame must be controlled in order to maximize the system's profit.
Glyphosate-resistant (GR) and glyphosate-tolerant weeds cause considerable yield losses and represent a growing threat to soybean production systems. Despite the relevance of this topic, few studies have evaluated the dispersal of these species in Brazil. The objective of this study was to evaluate the dispersal and frequency of known GR and glyphosate-tolerant weeds in soybean-producing microregions. A total of 2,481 interviews were conducted in different regions of Brazil. The interviews were stratified among 20 edaphoclimatic microregions (ECRs) to cover all of the country’s soybean-producing regions. A minimum number of interviews was estimated to generate a margin of error of ≤10% within the ECRs and ≤5% in the country. The values of the farmers’ responses were extrapolated to the total soybean production area of each ECR and the country as a whole, and the absolute values of each response were normalized as percentage values. The dispersal and management data demonstrate a loss of efficiency of glyphosate-resistance technology. Species that are naturally tolerant to glyphosate such as goosegrass, Commelina spp., and Ipomoea spp. had a greater presence in the ECRs, as did the resistant biotypes, particularly Conyza spp. and sourgrass, due to the large area cultivated with GR soybean, where glyphosate has been used with high frequency.
Recent open-label trials show that psychedelics, such as ayahuasca, hold promise as fast-onset antidepressants in treatment-resistant depression.
Methods
To test the antidepressant effects of ayahuasca, we conducted a parallel-arm, double-blind randomized placebo-controlled trial in 29 patients with treatment-resistant depression. Patients received a single dose of either ayahuasca or placebo. We assessed changes in depression severity with the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Hamilton Depression Rating scale at baseline, and at 1 (D1), 2 (D2), and 7 (D7) days after dosing.
Results
We observed significant antidepressant effects of ayahuasca when compared with placebo at all-time points. MADRS scores were significantly lower in the ayahuasca group compared with placebo at D1 and D2 (p = 0.04), and at D7 (p < 0.0001). Between-group effect sizes increased from D1 to D7 (D1: Cohen's d = 0.84; D2: Cohen's d = 0.84; D7: Cohen's d = 1.49). Response rates were high for both groups at D1 and D2, and significantly higher in the ayahuasca group at D7 (64% v. 27%; p = 0.04). Remission rate showed a trend toward significance at D7 (36% v. 7%, p = 0.054).
Conclusions
To our knowledge, this is the first controlled trial to test a psychedelic substance in treatment-resistant depression. Overall, this study brings new evidence supporting the safety and therapeutic value of ayahuasca, dosed within an appropriate setting, to help treat depression. This study is registered at http://clinicaltrials.gov (NCT02914769).
Selenium (Se) is an essential micronutrient for humans, yet its dietary intake is low, mostly due to the low bioavailability in soils and therefore in edible plant tissues. To overcome Se deficiency, the breeding approach (i.e., genetic biofortification), namely in rice, is largely dependent on available Se pools. To ensure the success of genetic biofortification with Se, agronomic biofortification can be accomplished through foliar Se application. Considering this background, the main hypothesis of this work was centered in the foliar application of Se to attain agronomic biofortification of rice crops. This study also aimed to assess the full potential for increasing grain Se concentrations during rice filling, as well as the types of nutrients deposition. An experimental design applying two foliar fertilizers (sodium selenite and sodium selenate) was developed. As test systems, four rice genotypes (Ariete, Albatros, OP1105 and OP1109) were used and the kinetics of micro- and macro-nutrients accumulation and deposition were assessed. Biofortification was performed in field trials for two years with foliar fertilization ranging between 0 and 300 g Se ha−1. At the end of the plant cycle, selenite applications triggered 427- to 884-fold increases in grain Se concentrations among rice genotypes (Albatros > OP1105 > OP1109 > Ariete). The application of selenate also prompted 128- to 347-fold increases in grain Se concentrations in rice crops (Albatros > OP1105 > Ariete > OP1109). Regardless of the foliar fertilizer applied, Se deposition among genotypes occurred throughout the grain without relevant inhibitory effects on yields. In each genotype, micro and macronutrients varied among crop tissues.
The Suape coastal zone has suffered since the 1980s the effects of anthropogenic action due to the construction of the industrial complex of Suape. This work aimed to evaluate the environmental conditions and possible eutrophication processes of the area. Six campaigns were carried out, three in the dry season (November 2015, January and April 2016) and three in the rainy season (July 2015, July and August 2016). Water samples were collected at the surface during low tide and high tide, in neap tides. Salinity ranged from 19.75 to 37.20, the dissolved oxygen rate ranged from 61.75 to 125.90% and chlorophyll-a from 0.02 to 3.48 mg m−3. Water transparency, temperature, nitrate and silicate presented significant seasonal variation, the concentrations of nutrients being higher in the rainy season and the others in the dry season. Water transparency, salinity, dissolved oxygen saturation and chl-a <20 µm showed significant differences for tide, being higher at high tide, and at low tide for chl-a of <20 µm. The low content of dissolved inorganic nutrient salts and chl-a were indicative of an area still free of eutrophication. Anthropogenic changes in the environment have led to greater marine interference and consequently to a reduction of the productive capacity of the system.