Non-tropical Regions Research Articles

Temperature Variability and the Macroeconomy: A World Tour

AbstractThis paper uses historical monthly temperature level data for a panel of 114 countries to identify the effects of within year temperature level variability on productivity growth in five different macro regions, i.e., (1) Africa, (2) Asia, (3) Europe, (4) North America and (5) South America. We find two primary results. First, higher intra-annual temperature variability reduces (increases) productivity in Europe and North America (Asia). Second, higher intra-annual temperature variability has no significant effects on productivity in Africa and South America. Additional empirical tests indicate also the following: (1) rising intra-annual temperature variability reduces productivity (even thought less significantly)in both tropical and non-tropical regions, (2) inter-annual temperature variability reduces (increases) productivity in North America (Europe) and (3) winter and summer inter-annual temperature variability generates a drop in productivity in both Europe and North America. Taken together, these findings indicate that temperature variability shocks tend to have stronger adverse economic effects among richer economies. In a production economy featuring long-run productivity and temperature volatility shocks, we quantify these negative impacts and find welfare losses of 2.9% (1%) in Europe (North America).

Global changes in the spatial extents of precipitation extremes

Understanding the variability of spatial extents of precipitation extremes favors an accurate assessment of the severity of disasters caused by extreme precipitation events. Using a restricted neighborhood method, we identify the spatial extents of global precipitation extremes over 1983–2018 and examine their spatiotemporal variability and associated changes. Results show that the mid-latitudes shows the largest spatial extent of precipitation extremes, and the spatial extents in non-tropical regions over the Northern Hemisphere show significant seasonal differences. In non-monsoon regions, the spatial extents of precipitation extremes in autumn and winter are larger than those in spring and summer, and the annual average spatial extents of precipitation extremes all exceed 500 km, which are larger than those in monsoon regions. All the five non-monsoon regions over the Northern Hemisphere and three monsoon regions in the western Pacific show statistically significant increases in the spatial extent of precipitation extremes in most seasons.

Patterns and drivers of genetic diversity among Felidae species

Since the late Pleistocene, species in the order Carnivora have experienced a drastic reduction in their populations and distributions. However, the global genetic diversity patterns among terrestrial carnivores have not been investigated. Using felid species as model, we characterized the genetic variation within their populations among continents, between tropical and non-tropical regions, and in relation to human activities. We then evaluated how species traits influence the observed patterns of interspecific genetic diversity. Through data collected from 135 population genetic studies conducted on 28 wild felid species (70% of the described species), data analyses using GLMM modelling showed that the populations in Africa and South America have significantly higher heterozygosity and allelic richness than those in other continents. The Asiatic lions have the least genetic diversity compared to other felids in the world. Threatened species have significantly lower genetic diversity compared to low-risk species as predicted. However, genetic diversity was not related to species body mass or geographic range. We found generation length to be an important variable explaining genetic diversity variation, in which species with short generation length have reduced genetic diversity. Furthemore, the combination of generation length, habitat and home range size captures the variation in heterozygosity significantly better. Species dependent on closed-habitat and with large home range size have reduced heterozygosity compared to their counterparts. Our results allow to identify priority felid species vulnerable to loss of genetic diversity for further conservation studies, and provide an insight into the possible genetic consequences of the late Pleistocene extinctions.

Global Patterns and Climate Controls of Terrestrial Ecosystem Light Use Efficiency

AbstractLight use efficiency (LUE) is a critical parameter, on which we rely to quantify the vegetation's capability to harvest solar energy and thus the photosynthesis carbon uptake. However, our understanding on its magnitude, global pattern, and climatic drivers remains uncertain. In this study, we investigated global mean annual LUE during 1980–2013 based on state‐of‐the‐art estimates from scaled‐up eddy covariance measurements (data‐driven models) and 10 process‐based models used in Global Carbon Project. We found comparable global LUE estimates from data‐driven models (0.90 ± 0.25 g C MJ−1) and process‐based models (0.73 ± 0.22 g C MJ−1), with individual model estimates ranging from 0.49 to 0.98 g C MJ−1. While both types of models agreed on highest LUE over the tropical evergreen forests, discrepancies remained over middle and high latitudes of the Northern Hemisphere, which probably resulted from different response of LUE to climatic factors. Spatial analyses revealed that LUE variations were more driven by temperature and precipitation than by solar radiation. While the response of LUE to precipitation was almost always positive globally, the response of LUE to temperature was only positive in part of the nontropical regions. Process‐based models showed that precipitation strongly regulated the response of LUE to temperature, which shifted from negative to positive when mean annual precipitation was larger than 1,000 mm yr−1. Our results provide converging global LUE estimates and highlight the need to take fully account of interactive effects of climatic factors in regulating LUE and thus the response of photosynthesis to climate change.

Legality requirements for wood import in the EU: Who wins, who loses?

This paper presents a spatial equilibrium model to analyses the leverage impact of the legality requirements in the EU Timber Regulation (EUTR). The EUTR is part of the EU's Forest Law Enforcement, Governance and Trade (FLEGT) program, which aims to stimulate legal wood production and sustainable forest management at global level. This leverage effect is an argument in favor of FLEGT but it has never been investigated thoroughly, nor simultaneously for demand and supply. The leverage effect is measured in terms of the market share of legal wood (i.e. accompanied by a license which approves its legality) in total wood production. Our research finds that FLEGT does not increase legal wood production and consumption. FLEGT creates a non-tariff trade barrier at the non-tropical regions' conventional wood markets. This situation allows conventional wood producers to benefit from monopoly rents. The presence of transport costs prevents consumers to switch to foreign producers. In addition, producers in tropical regions cannot compete with the more efficient producers in the non-tropical regions on the certified market. As such, FLEGT curtails part of the international trade flows which decrease the global quasi-welfare, with especially consumers being hit. To tackle those issues, non-compliant producer should be assisted in reaching the legality requirements to turn FLEGT into a fully inclusive policy. In addition, consumers should be engaged to pay a price premium to compensate the additional costs related to legal wood production.

Optimising Window Design on Residential Building Facades by Considering Heat Transfer and Natural Lighting in Nontropical Regions of Australia

Windows account for a significant proportion of the total energy lost in buildings. The interaction of window type, Window-to-Wall Ratio (WWR) scheduled and window placement height influence natural lighting and heat transfer through windows. This is a pressing issue for nontropical regions considering their high emissions and distinct climatic characteristics. A limitation exists in the adoption of common simulation-based optimisation approaches in the literature, which are hardly accessible to practitioners. This article develops a numerical-based window design optimisation model using a common Building Information Modelling (BIM) platform adopted throughout the industry, focusing on nontropical regions of Australia. Three objective functions are proposed; the first objective is to maximise the available daylight, and the other two emphasize undesirable heat transfer through windows in summer and winter. The developed model is tested on a case study located in Sydney, Australia, and a set of Pareto-optimum solutions is obtained. Through the use of the proposed model, energy savings of up to 8.57% are achieved.

A systematic literature review of leptospirosis outbreaks worldwide, 1970–2012

ABSTRACTObjective.This review describes the geographic and temporal distribution of, detection methods for, and other epidemiological features of published leptospirosis outbreaks, with the aim of informing efforts to standardize outbreak-reporting practices.Methods.We conducted a systematic review of leptospirosis outbreaks reported in the scientific literature and ProMED during 1970–2012. Predefined criteria were used to identify and classify outbreaks and a standard form was used to extract information.Results.During 1970–2012, we identified 318 outbreaks (average: 7 outbreaks/year; range: 1–19). Most outbreaks were reported in the Latin America and the Caribbean region (36%), followed by Southern Asia (13%), and North America (11%). Most outbreaks were located in tropical and subtropical ecoregions (55%). Quality classification showed that there was clear description of laboratory-confirmed cases in 40% of outbreaks. Among those, the average outbreak size was 82 cases overall (range: 2–2 259) but reached 253 cases in tropical/subtropical ecoregions. Common risk factors included outdoor work activities (25%), exposure to floodwaters (23%), and recreational exposure to water (22%). Epidemiologic investigation was conducted in 80% of outbreaks, mainly as case interviews. Case fatality was 5% overall (range: 0%–60%).Conclusions.Outbreak reporting increased over the study period with outbreaks covering tropical and non-tropical regions. Outbreaks varied by size, setting, and risk factors; however, data reviewed often had limited information regarding diagnosis and epidemiology. Guidelines are recommended to develop standardized procedures for diagnostic and epidemiological investigations during an outbreak and for reporting.

A Two-Patch Mathematical Model for Temperature-Dependent Dengue Transmission Dynamics

Dengue fever has been a threat to public health not only in tropical regions but non-tropical regions due to recent climate change. Motivated by a recent dengue outbreak in Japan, we develop a two-patch model for dengue transmission associated with temperature-dependent parameters. The two patches represent a park area where mosquitoes prevail and a residential area where people live. Based on climate change scenarios, we investigate the dengue transmission dynamics between the patches. We employ an optimal control method to implement proper control measures in the two-patch model. We find that blockage between two patches for a short-term period is effective in a certain degree for the disease control, but to obtain a significant control effect of the disease, a long-term blockage should be implemented. Moreover, the control strategies such as vector control and transmission control are very effective, if they are implemented right before the summer outbreak. We also investigate the cost-effectiveness of control strategies such as vaccination, vector control and virus transmission control. We find that vector control and virus transmission control are more cost-effective than vaccination in case of Korea.

A case report of a 40-year-old woman with endomyocardial fibrosis in a non-tropical area: from initial presentation to high urgent heart transplantation

BackgroundEndomyocardial fibrosis (EMF) represents the most common cause of restrictive cardiomyopathy worldwide. Despite a high prevalence in tropical regions, it occasionally occurs in patients who have never visited these areas. While researches have proposed various possible triggers for EMF, etiology and pathogenesis remain largely unknown. Diagnosis is based on patient history, heart failure symptoms, and echocardiographic signs of restrictive ventricular filling, atrioventricular valve regurgitation and frequently apical thrombus. Following is a case report of an Austrian patient with EMF who eventually had to undergo a heart transplant. This case report strives to promote awareness for this in non-tropical areas uncommon but nevertheless detrimental disease.Case presentationA 40-year-old woman was presented at our emergency department with chest pain and fever up to 38.1° Celsius. Plasma troponin-T levels and inflammatory markers were slightly elevated, but the echocardiogram was without pathological findings. The patient was hospitalized on the suspicion of acute myocarditis and discharged soon after improvement. Eight months later, she was presented again with chest pain and symptoms of heart failure. The echocardiogram showed normal systolic left ventricular (LV) function with LV wall thickening and severe restrictive mitral regurgitation as well as aortic and tricuspid regurgitation. Coronary angiogram was normal but right heart catheterization showed pulmonary hypertension due to left heart disease. Further diagnostic workup with cardiac magnetic resonance imaging revealed subendocardial late enhancement and apical thrombus formation in the left ventricle compatible with the diagnosis of EMF. A comprehensive diagnostic workup showed no evidence of infection, systemic immunologic or hematological disease, in particular hypereosinophilic syndrome. After a multidisciplinary consideration of several therapeutic options, the patient was listed for heart transplantation. On the waiting list, she deteriorated rapidly due to progressive heart failure and finally underwent a heart transplantation. Histological examination confirmed the diagnosis of EMF. Six years after her heart transplantation, the patient was presented in an excellent clinical condition.ConclusionsEven in non-tropical regions, the diagnosis of EMF should always be considered in restrictive cardiomyopathy. Knowledge of the distinct phenotype of EMF facilitates diagnosis, but comprehensive workup and therapeutic management remain challenging and require a multidisciplinary approach.

INNOVATIVE PROPOSITION AND PREDICTION OF URBAN WET WEATHER WASHOFF USING SIMULATED RAINFALL

Washoff is an important process that describes the transportation of pollutants into water ways during the wet weather event. Washoff is a multifarious phenomenon that encapsulated other varied processes ranging from the pollutants deposition during the dry weather period (buildup), to the higher load transport at the beginning of the storm (first flush). Most of the washoff studies were localised to non-tropical regions, where the laxity to wait for dry weather period exist. However, in the tropical regions, the assurance for prolonged dry weather period is near absent, due to frequency of rainfall. This research experimented two new approaches to washoff sampling suitable for tropical regions, alongside with the traditional washoff sampling method. To obtain highly accurate data, the rainfall parameters were confined to selection by employing a very efficient rainfall simulator to gain the washoff data. The washoff of Total suspended solids (TSS) as an indicator of pollution under different simulated rainfalls was established. The result indicated higher mobilisation of the TSS in the first five minutes of rain, and disposes to a steady mobilisation rate after 40 minutes of simulated rain. The washoff percentages for the three road surfaces suggests that the rain intensity plays a more prominent role in washoff prior to the occurrence of first flush, while intense rain mobilises higher amount of TSS within shorter duration of rain. The first flush effect was quantified based on the common definitions of pollutants load-volume relationships of 20/80, 30/80, and 20/40. In all the road surfaces, at least 40% of the pollutants loads were transported in the first 20% of the runoff volumes.

INNOVATIVE PROPOSITION AND PREDICTION OF URBAN WET WEATHER WASHOFF USING SIMULATED RAINFALL

Washoff is an important process that describes the transportation of pollutants into water ways during the wet weather event. Washoff is a multifarious phenomenon that encapsulated other varied processes ranging from the pollutants deposition during the dry weather period (buildup), to the higher load transport at the beginning of the storm (first flush). Most of the washoff studies were localised to non-tropical regions, where the laxity to wait for dry weather period exist. However, in the tropical regions, the assurance for prolonged dry weather period is near absent, due to frequency of rainfall. This research experimented two new approaches to washoff sampling suitable for tropical regions, alongside with the traditional washoff sampling method. To obtain highly accurate data, the rainfall parameters were confined to selection by employing a very efficient rainfall simulator to gain the washoff data. The washoff of Total suspended solids (TSS) as an indicator of pollution under different simulated rainfalls was established. The result indicated higher mobilisation of the TSS in the first five minutes of rain, and disposes to a steady mobilisation rate after 40 minutes of simulated rain. The washoff percentages for the three road surfaces suggests that the rain intensity plays a more prominent role in washoff prior to the occurrence of first flush, while intense rain mobilises higher amount of TSS within shorter duration of rain. The first flush effect was quantified based on the common definitions of pollutants load-volume relationships of 20/80, 30/80, and 20/40. In all the road surfaces, at least 40% of the pollutants loads were transported in the first 20% of the runoff volumes.

Seasonal and regional patterns of lower leg cellulitis in Western Australia.

Lower leg cellulitis (LLC) is a common infection that is usually caused by Streptococcus pyogenes or other beta-haemolytic streptococci. We hypothesised that in Western Australia (WA), LLC is a summer disease and would be more common in the northern, tropical regions. We conducted a statewide data linkage of adult patients presenting to WA hospitals with a first ever diagnosis of LLC, from January 2002 through December 2013 according to the region and season. A total of 36 276 cases presented with a primary episode of LLC. The northern regions of the Kimberley (2.26 (2.13-2.39), P < 0.001) and midwest (1.13 (1.06-1.20), P < 0.001) had higher incidence rates than the Perth metropolitan region, while the southern regions of Southwest, Great Southern and Goldfields had lower incidence rates (0.89 (0.85-0.93), P < 0.001; 0.81 (0.75-0.88), P < 0.001; and 0.77 (0.71-0.83), P < 0.001, respectively). The total number of primary cases was higher in summer (10 570 (29.1%, 95% confidence interval 28.7-29.6), P < 0.0001) and autumn (9306 (25.7%, 95% confidence interval 25.2-26.1), P = 0.004). Seasonality of LLC was observed in all WA regions except those in the Kimberley, Pilbara and Great Southern regions. In most non-tropical regions of WA, LLC is a summer disease, while in the warmer tropical regions of WA where year-round temperatures are higher, no seasonality was observed, but overall incidence of LLC presentations were higher. These findings may have important implications for public health messaging and research around prevention of LLC.

Seasonal effects on behavior and immunity in a precocial rodent

Environmental variation strongly influences individual life histories, behavior, and immunity. For many animals living in non-tropical regions, environmental variation due to season is very important and can be reliably predicted by photoperiod. By manipulating the pre- and post-natal photoperiod for cavies (Cavia aperea), we simulated different birth seasons that go along with predictable differences in life history. Offspring born into simulated spring conditions mature earlier, indicating a fast pace of life compared to offspring born into simulated fall. We investigated the development of two innate (titers of natural antibodies and complement) and one adaptive (immunoglobulin G) immune effectors across multiple life stages. In addition, we tested if three behaviors, indicating risk-taking and stress-coping, differed between seasons. Finally, we tested if behaviors and immune traits correlate with each other as predicted by the pace-of-life syndrome hypothesis. The season of birth influenced average trait expression of both immunity and behavior. Boldness, indicating risk-taking behavior, correlated positively with the titers of natural antibodies, fitting the predictions of the pace-of-life syndrome (POLS). However, fearlessness, indicating how an individual copes with a stressful situation, correlated positively with immunoglobulin G concentrations, against the predictions of the POLS. Together, our results show that behaviors and immune traits react to differences in expected life histories, but do not show the predicted covariation. We conclude that proximate mechanisms and different functions of traits need to be considered to predict the nature of behavior-immune associations. Individual life histories, behavior, and immunity are strongly influenced by the environment individual’s experience during early life. Recent theory predicts correlations between behavior and immunity to arise as a consequence of different life histories. By simulating different birth seasons, we induced different life history expectations as well as a season-dependent development of immunity and behavior. However, correlations between behavior and immunity do not fit theoretical predictions, highlighting the need for more detailed theory.

Long-term charcoal-induced changes to soil properties in temperate regions of northern Iran

The long-term performance and benefits of charcoal application on the carbon sequestration and properties of forest soils in temperate or non-tropical regions has not been studied in detail in spite of its important role in global warming. This study was conducted to describe the long-term charcoal-induced changes in organic carbon (OC) content and other soil properties of temperate deciduous forests in Mazandaran province, northern Iran. Three sites were sampled to collect composite soil samples from two depths (0–20 and 20–40 cm) inside and outside of a plot of charcoal-enriched soils surrounding a historical charcoal production site (abandoned for more than 120 years). The presence of charcoal in soils for about 120 years elevated significantly the black carbon, total OC, natural soil OC, total nitrogen, dissolved organic matter, soil OC density, exchangeable bases, saturated hydraulic conductivity, available water capacity and available Fe, Mn and Zn compared to the adjacent reference soils. Cation exchange capacity (CEC) and pH were 15.5 cmolc kg−1 and 0.5 units, respectively, higher than the adjacent reference soils at 0–20 cm soil depth. However, electrical conductivity (EC), bulk density and available Cu were higher in the adjacent reference soil. The aged charcoal had no significant effect on the microbial respiration rate of studied soils. The results of this study provide new insights and strong support for the long-term benefits of biochar application as a management strategy for improving soil productivity as well as sequestering large quantities of durable carbon in soils of the region and mitigating global warming.

Is Climate Associated With Revision for Prosthetic Joint Infection After Primary TKA?

Climate factors have been shown to be associated with spontaneous musculoskeletal and some surgical site infections with increased rates of infection during warmer periods. To date, little research has been performed to determine if this phenomenon is associated with differences in the risk of revision for prosthetic joint infection (PJI) in primary TKA. (1) Does the rate of revision for early PJI within the first year after primary TKA differ between tropical and nontropical regions? (2) Is there a seasonal variation in the rate of revision for PJI? (3) Is the geographic and seasonal variation (if present) associated with the sex, age, and/or American Society of Anesthesiologists (ASA) grade of the patient? All 219,983 primary TKAs performed for osteoarthritis over a 5-year period (2011-2015) in the Australian Orthopaedic Association National Joint Replacement Registry were examined based on the month of the primary procedure to determine the rate of revision for PJI within 12 months. The data were analyzed to determine the differences in the risk of revision for PJI based on geographic region and season of the primary procedure adjusting for sex, age, and ASA grade of the patient. The early revision rate for PJI was higher in the tropical compared with the nontropical region of Australia (0.73% versus 0.37%; odds ratio [OR], 1.87; 95% confidence interval [CI], 1.44-2.42; p < 0.001). The tropical region of Australia demonstrated a seasonal variation in the rate of revision for PJI with a higher rate during the warmer monsoon wet season of summer and fall (summer/fall 0.98% versus winter/spring 0.51%; OR, 1.88; 95% CI, 1.12-3.16; p = 0.02). A seasonal variation was not seen in the nontropical region (OR, 1.03; 95% CI, 0.90-1.19; p = 0.64). The regional and seasonal changes were independent of sex, age, and ASA grade. Climate factors are associated with the risk of early revision for PJI in patients undergoing primary TKA with rates of such revisions approximately double in tropical regions compared with nontropical regions. Additionally, tropical regions demonstrate a seasonal variation with the risk of PJI doubling during the warmer, monsoonal wet season of summer and fall. These findings should be confirmed in further studies that can better control for possible confounding variables. The mechanism for this phenomenon is not clear, and further research into this subject is also indicated. Level III, therapeutic study.

Reliable Serological Testing for the Diagnosis of Emerging Infectious Diseases.

Climate change, increased urbanization and international travel have facilitated the spread of mosquito vectors and the viral species they carry. Zika virus (ZIKV) is currently spreading in the Americas, while dengue virus (DENV) and chikungunya virus (CHIKV) have already become firmly established in most tropical and also many non-tropical regions. ZIKV, DENV and CHIKV overlap in their endemic areas and cause similar clinical symptoms, especially in the initial stages of infection. Infections with each of these viruses can lead to severe complications, and co-infections have been reported. Therefore, laboratory analyses play an important role in differential diagnostics. A timely and accurate diagnosis is crucial for patient management, prevention of unnecessary therapies, rapid adoption of vector control measures, and collection of epidemiological data.There are two pillars to diagnosis: direct pathogen detection and the determination of specific antibodies. Serological tests provide a longer diagnostic window than direct methods, and are suitable for diagnosing acute and past infections, for disease surveillance and for vaccination monitoring. ELISA and indirect immunofluorescence test (IIFT) systems based on optimized antigens enable sensitive and specific detection of antibodies against ZIKV, DENV and CHIKV in patient serum or plasma. In recent years, Euroimmun (Lübeck, Germany) has developed numerous test systems for the serological diagnosis of (re-)emerging diseases, including a very sensitive and specific anti-ZIKV ELISA.

A further contribution to the seasonal variation of weighted mean temperature

The weighted mean temperature Tm is a variable parameter in the Global Navigation Satellite System (GNSS) meteorology and the Askne-Nordius zenith wet delay (ZWD) model. Some parameters about the Tm seasonal variation (e.g. the annual mean value, the annual range, the annual and semi-annual amplitudes, and the long-term trend) were discussed before. In this study, some additional results about the Tm seasonal variation on a global scale were found by using the Tm time series at 309 global radiosonde sites. Periodic signals of the annual and semi-annual variations were detected in these Tm time series by using the Lomb-Scargle periodogram. The annual variation is the main component of the periodic Tm in non-tropical regions, while the annual variation or the semiannual variation can be the main component of the periodic Tm in tropics. The mean annual Tm almost keeps constant with the increasing latitude in tropics, while it decreases with the increasing latitude in non-tropical regions. From a global perspective, Tm has an increasing trend of 0.22K/decade on average, which may be caused by the global warming effects. The annual phase is almost found in about January for the non-tropical regions of the Southern Hemisphere and in about July for the non-tropical regions of the Northern Hemisphere, but it has no clear symmetry in tropics. Unlike the annual phase, the geographical distributions of semi-annual phase do not follow obvious rules. In non-tropical regions, the maximum and minimum Tm of the seasonal model are usually found in respective summer and winter days while the maximum and minimum Tm are distributed over a whole year but not in any fixed seasons for tropical regions. The seasonal model errors increase with the increasing value of annual amplitude. A primary reason for the irregular seasonal variation in tropics is that Tm has rather small variations in this region.

The Seasonal Variation of TKR Infection Rates

Introduction:A seasonal variation in the incidence of surgical site infections has been described following a number of common surgical procedures. However in the setting of elective Total Knee Replacement (TKR), the role of environmental factors is an area of research that is currently lacking from the literature. Data recently presented from our institution demonstrates a possible trend toward higher infection rates during periods of increased temperature and humidity. The aim of this study was to investigate if seasonal and geographical factors influence the rate of TKR infection within Australia.Methods:Data from the AOA National Joint Registry for all primary TKRs performed within the last 5 years was analysed to determine the revision rates for early (<12 months) post-operative infection. The infection rates for tropical regions (Darwin, Cairns, Townsville, Mackay) were compared to the remainder of the country. A month-by-month analysis was performed to determine if there was a seasonal variation within the 2 study groups.Results:During the study period a total of 207,540 primary TKRs were performed (6,514 tropical vs 201,026 non-tropical regions). Overall, the rate of revision for infection was significantly higher for the tropical regions of Australia (0.80% vs 0.39%). In non-tropical regions, there was no observed seasonal variation of infection rates. In tropical regions, there was a clear seasonal variation found, with the winter months being associated with a significantly lower rate of infection than the remainder of the year (0.37% vs 0.94%). The infection rates were not significantly different between tropical (0.37%) and non- tropical (0.38%) regions during the winter period.Conclusion:To the best of our knowledge, this is the first study to investigate and demonstrate a significant influence from seasonal variation on primary TKR infection rates. This phenomenon is evident only within tropical regions, with the periods of warmer and humid weather resulting in a significantly increased risk of primary TKR infection. These findings require further investigation and research.

Importance of riparian habitat for frugivorous bats in a tropical dry forest in western Mexico

Abstract:Riparian forests (RF) provide shelter, feeding resources and commuting areas and are fundamental for local fauna during long drought periods in tropical dry forests. Nevertheless, information regarding vertebrate ecology in tropical RF is scarce. The studies of bats in riparian habitats have been mostly focused on insectivorous assemblages in non-tropical regions. We contrasted the occurrence of frugivorous bats between RF and upland dry forest (UDF) in a Neotropical dry forest region and evaluated how vegetation structure modulates frugivorous bat presence and abundance. We sampled bat ensembles and vegetation structure in three UDF and three RF sites in Jalisco, Mexico. Bat ensembles and populations were analysed with generalized linear models, including as independent factors: (1) habitat and (2) vegetation attributes. In 72 nights we captured 840 bats belonging to seven species. No effect of habitat type or vegetation structure on species richness was found, but habitat type did affect bat species composition and abundance. Moreover, vegetation structural traits affected frugivorous bat abundance. Frugivore abundance was higher in RF than in UDF probably because RF provides greater resources and more roosting sites. Riparian forests also present more canopy cover and accessible flight spaces. Our results support the importance of RF for frugivorous bats in terms of abundance and composition. Additionally, the lack of differences in species richness between UDF and RF highlights the importance of both habitats for maintaining frugivorous bats, as well as the related ecosystem processes and services in tropical dry forest landscapes.

Relationship between vitamin D status, glycemic control and cardiovascular risk factors in Brazilians with type 2 diabetes mellitus.

ObjectivesDetermine the prevalence and identify predictors of hypovitaminosis D in patients with type 2 diabetes mellitus (T2DM); 2) correlate vitamin D levels with variables indicative of glycemic control and cardiovascular risk.Research design and methodsWe conducted a cross-sectional study with consecutive patients treated at a University Hospital’s Endocrinology outpatient clinic located at 12°58′S latitude, between October 2012 and November 2013. Hypovitaminosis D was defined as 25-hydroxyvitamin D < 30 ng/mL (chemiluminescence).ResultsWe evaluated 108 patients with mean duration of T2DM of 14.34 ± 8.05 years and HbA1c of 9.2 ± 2.1%. Mean age was 58.29 ± 10.34 years. Most were women (72.2%), non-white (89.8%) and had hypertension (75.9%) and dyslipidemia (76.8%). Mean BMI was 28.01 ± 4.64 kg/m2; 75.9% were overweight. The prevalence of hypovitaminosis D was 62%. In multiple logistic regression, independent predictors of hypovitaminosis D were female gender (OR 3.10, p = 0.02), dyslipidemia (OR 6.50, p < 0.01) and obesity (OR 2.55, p = 0.07). In multiple linear regression, only total cholesterol (β = −0.36, p < 0.01) and BMI (β = −0.21, p = 0.04) remained associated with levels of 25-hydroxyvitamin D.ConclusionsUsing currently recommended cutoffs, the prevalence of hypovitaminosis D in Brazilians with T2DM was as high as that of non-tropical regions. Female gender, dyslipidemia and obesity were predictors of hypovitaminosis D. Low levels of 25-hydroxyvitamin D were correlated with high cholesterol and BMI values. Future studies are needed to evaluate whether vitamin D replacement would improve these parameters and reduce hard cardiovascular outcomes.