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Refractive errors are the most common causes of vision impairment worldwide and laser refractive surgery is one of the most frequently performed ocular surgeries. Clinical studies have reported that approximately 10.5% of patients need an additional procedure after the surgery. The major complications of laser surgery are over/under correction and dry eye. An increase in temperature may be a cause for these complications. The purpose of this study was to estimate the increase in temperature during laser refractive surgery and its relationship with the complications observed for different surgical techniques. In this paper, a finite element model was applied to investigate the temperature distribution of the cornea when subjected to ArF excimer laser at a single spot using various beam delivery systems (broad beam, scanning slit, and flying spot). The Pennes bio-heat equation was used to predict the temperature values at different laser pulse energies and frequencies. The maximum temperature increase by ArF laser ([Formula: see text] frequency and [Formula: see text] pulse energy) at a single spot was [Formula: see text] for [Formula: see text] diopter correction ([Formula: see text] of ablation of corneal stroma) using broad beam, scanning slit, and flying spot beam delivery approaches respectively. The peak temperature due to a single pulse was estimated to be [Formula: see text]. Although the peak temperature (sufficient energy to break intermolecular bonds) exists for a very short time ([Formula: see text]) compared to the thermal relaxation time ([Formula: see text]), there is some thermal energy exchange between corneal tissues during a laser refractive surgery. Heating may cause collagen denaturation, collagen shrinkage, and more evaporation and hence proposed to be a risk factor for over/under correction and dry eye., (© 2021. The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.)

Background: Published information on snakebite is rare in Bhutan although remarkably higher number of snakebites and associated deaths are reported from other South Asian countries., Aims and Methodology: Structured questionnaire was used to collect knowledge of health workers in snakebite management and health seeking behavior of snakebite victims as observed by health workers. Study was conducted in purposively sampled 10 Dzongkhags (district level administrative units) with higher incidence of snakebites., Result: Heath workers scored 27-91% (with an average of 63%, SD = 14) for 52 questions related to snake identification and snakebite management. Among 118 health workers interviewed, 23% had adequate knowledge on snakes and snakebite management while 77% had inadequate knowledge. Among 32 Doctors, 63% of them scored above or equal to 75%. Health workers from Sarpang scored higher (76%, SD = 11) than those from other Dzongkhags. Snakebite victim's visit to local (traditional) healers prior to seeking medical help from hospital was observed by 75 (63%) health workers. Fifty one percent of health workers observed patients treated with local methods such as the use of black stone called Jhhar Mauro (believed to absorb snake venom), application of honey, rubbing of green herbal paste made up of Khenpa Shing (Artemisia myriantha Wallich ex Besser var. paleocephala [Pamp] Ling) and consumption of fluid made up of Neem leaf (Azadirachta indica Juss). Use of tight tourniquet as a first aid to snakebite was observed by 80% of the health workers., Conclusion: Health workers lack confidence in snakebite management. Snakebite victims are likely to suffer from harmful local practices and traditional beliefs on local treatment practices. Empowering health workers with adequate knowledge on snakebite management and making locals aware in pre-hospital care of snakebites are needed to improve the pre- and in-hospital management of snakebite in Bhutan., Competing Interests: The authors have declared that no competing interests exist.

Dengue fever is a mosquito-borne infectious disease threatening more than a hundred tropical countries of the world. The heterogeneity of mosquito bites of human during the spread of dengue virus is an important factor that should be considered while modeling the dynamics of the disease. However, traditional models assumed homogeneous transmission between host and vectors which is inconsistent with reality. Mathematically, we can describe the heterogeneity and uncertainty of the transmission of the disease by introducing fuzzy theory. In the present work, we study transmission dynamics of dengue with the fuzzy SEIR-SEI compartmental model. The transmission rate and recovery rate of the disease are considered as fuzzy numbers. The dynamical behavior of the system is discussed with different amounts of dengue viruses. Also, the fuzzy basic reproduction number for a group of infected individuals with different virus loads is calculated using Sugeno integral. Simulations are made to illustrate the mathematical results graphically., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2020 G. Bhuju et al.)

Torrent catfishes of the subfamily Glyptosterninae from Bhutan are examined based on morphological and molecular data. Five new species are described: Creteuchiloglanis bumdelingensis sp. nov., Exostoma mangdechhuensis sp. nov., Parachiloglanis benjii sp. nov., P. dangmechhuensis sp. nov., and P. drukyulensis sp. nov. Molecular data derived from the mitochondrial gene Cyt b and the nuclear gene RAG2 recovered relationships within Parachiloglanis and the Glyptosterninae. A dichotomous key to the Glyptosterninae of Bhutan is provided.

Dengue is a vector-borne infectious disease endemic in many parts of the world. The disease is spreading in new places due to human movement into the dengue disease supporting areas. Temperature is the major climatic factor which affects the biological processes of the mosquitoes and their interaction with the viruses. In the present work, we propose a multipatch model to assess the impact of temperature and human movement in the transmission dynamics of dengue disease. The work consists of system of ordinary differential equations that describe the transmission dynamics of dengue disease between humans and mosquitoes. Human population is divided into four classes: susceptible, exposed, infectious, and recovered. Mosquito population is divided into three classes: susceptible, exposed, and infectious. Basic reproduction number ℛ 0 of the model is obtained using Next-Generation Matrix method. The qualitative analysis of the model is made in terms of the basic reproduction number. Parameters used in the model are considered temperature dependent. Dynamics of vector and host populations are investigated with different human movement rates and different temperature levels. Numerical results show that proper management of human movement between patches helps reducing the burden of dengue disease. It is also seen that the temperature affects the transmission dynamics of the disease significantly.

Seven species of Garra are herein accounted for in Bhutan. Three new records of known species, G. arupi, G. birostris, and G. lissorhynchus, and two new species, G. bimaculacauda sp. nov. and G. parastenorhynchus sp. nov., are reported from central and southern Bhutan. Garra bimaculacauda sp. nov. is most notably different from its congeners by the presence of two dark spots on the lobes of the caudal fin, having one spot on each lobe. Meristic and morphometric differences from northeastern Indian congeners exist as well. Garra parastenorhynchus sp. nov. is differentiated from its congeners by the presence of a prominent, overhanging, club-shaped proboscis, and a suite of meristic and morphometric characters. Notes on the taxonomy are provided for some species. Notes are provided on the biology and ecology for most species, which have been inferred from field observations. Ranges are expanded for two recently described taxa from Northeast India G. arupi, and G. birostris. A key is provided to the currently known species of Garra within Bhutan.

Parachiloglanis bhutanensis is a newly discovered species of torrent catfish from eastern Bhutan. With its discovery, the genus Parachiloglanis is no longer monotypic. The species differs from Parachiloglanis hodgarti in meristic, mensural, and coloration characters. Parachiloglanis bhutanensis is confirmed as a member of the genus by the absence of a post-labial grove on the lower lip, which is present in other genera of the subfamily Glyptosterninae (as either complete or incomplete). It is diagnosed within the genus by the presence (versus absence) of a series of 35-40 large white pores along the lateral line, a tall adipose fin (roughly two times the height of the adipose fin in P. hodgarti), a less dorsoventrally flattened body than P. hodgarti, a deeper head, wider mouth, longer inner- and outer-mandibular barbels, a truncate (versus indented to lunate) caudal fin, and the absence (versus presence) of black and white pigmentation on the caudal fin.

Skin temperature is a common physiological parameter that reflects thermal responses. Blood perfusion is an important part of the physiological processes that the human body undergoes in order to maintain homeostasis. This study focuses on the effect of perfusion on the temperature distribution in human males and females body in different thermal environment. The study has been carried out for one dimensional steady cases using finite element method. The input parameter of the model is the blood perfusion or volumetric flow rate within the tissue. The appropriate physical and physiological parameters together with suitable boundary conditions that affect the heat regulations have been incorporated in the model. The study is to have a better understanding that how does thermoregulation change in human males and females skin layered due to perfusion., (Copyright © 2014 Elsevier Ltd. All rights reserved.)