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2021 ◽  
Vol 12 (45) ◽  
pp. 168-177
Author(s):  
Subhasish Ganguly ◽  
Subhranil Saha ◽  
Munmun Koley ◽  
Ramkumar Mondal

Background: Vitiligo is a common hypopigmentation disorder with significant psychological impact. An evaluation of homeopathic treatment was performed in individuals with vitiligo in a hospital outpatient clinic in West Bengal, India. Methods: Thirty participants (median age 27 years old, 57% female) were recruited for a prospective open-label pilot study and treated with individualized homeopathic medicines for 6 months. Efficacy was assessed after 3 months and 6 months using Vitiligo Area Scoring Index (VASI) score, Vitiligo European Task Force (VETF) score, and Dermatological Life Quality Index (DLQI) score, which are validated outcome measures evaluating the area, intensity, spread of depigmentation of vitiligo lesions, and quality of life (QoL). Results: A total of 27 participants completed the trial; 3 dropped out. After 6 months of treatment, the median VASI total score improved significantly by 0.1 units (p=0.003), from 0.8 (0.5, 1.5) to 0.7 (0.3, 0.8) on a scale from 0 (no depigmentation) to 100 (completely depigmented). Similarly, the VETF median score improved by 2 units (p=0.0001) from 1 (0, 1) to –1 (–1, 0) and the staging score changed from 1 (1, 2) to 1 (0, 1), p=0.002. The total DLQI median score exhibited significant reduction from 21 (17, 22) to 13.6 (10, 17), change 7.4 (p=0.0001), as also did its components. Conclusions: Individualized homeopathic treatment associated with significant improvement of VASI, VETF and DLQI scores. The extent to which the observed effects were due to placebo needs clarification in future randomized double-blind clinical studies preceded by feasibility studies. Trial Registration: Clinical Trials Registry, India registration number CTRI/2013/08/003879.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Tirtha Banerjee ◽  
Warren Heilman ◽  
Scott Goodrick ◽  
J. Kevin Hiers ◽  
Rod Linn

Abstract Increasing trends in wildfire severity can partly be attributed to fire exclusion in the past century which led to higher fuel accumulation. Mechanical thinning and prescribed burns are effective techniques to manage fuel loads and to establish a higher degree of control over future fire risk, while restoring fire prone landscapes to their natural states of succession. However, given the complexity of interactions between fine scale fuel heterogeneity and wind, it is difficult to assess the success of thinning operations and prescribed burns. The present work addresses this issue systematically by simulating a simple fire line and propagating through a vegetative environment where the midstory has been cleared in different degrees, leading to a canopy with almost no midstory, another with a sparse midstory and another with a dense midstory. The simulations are conducted for these three canopies under two different conditions, where the fuel moisture is high and where it is low. These six sets of simulations show widely different fire behavior, in terms of fire intensity, spread rate and consumption. To understand the physical mechanisms that lead to these differences, detailed analyses are conducted to look at wind patterns, mean flow and turbulent fluxes of momentum and energy. The analyses also lead to improved understanding of processes leading to high intensity crowning behavior in presence of a dense midstory. Moreover, this work highlights the importance of considering fine scale fuel heterogeneity, seasonality, wind effects and the associated fire-canopy-atmosphere interactions while considering prescribed burns and forest management operations.


Fire ◽  
2019 ◽  
Vol 2 (4) ◽  
pp. 60 ◽  
Author(s):  
Jonathan Reimer ◽  
Dan K. Thompson ◽  
Nicholas Povak

Most wildfires in North America are quickly extinguished during initial attack (IA), the first phase of suppression. While rates of success are high, it is not clear how much IA suppression reduces annual fire risk across landscapes. This study introduces a method of estimating IA effectiveness by pairing burn probability (BP) analysis with containment probability calculations based on initial fire intensity, spread rate, and crew response time. The method was demonstrated on a study area in Kootenay National Park, Canada by comparing burn probabilities with and without modeled IA suppression. Results produced landscape-level analyses of three variables: burn probability, suppression effectiveness, and conditional escape probability. Overall, IA reduced mean study area BP by 78% as compared to a no-suppression scenario, but the primary finding was marked spatial heterogeneity. IA was most effective in recently burned areas (86% reduction), whereas mature, contiguous fuels moderated its influence (50%). Suppression was least effective in the designated wildfire exclusion zone, suggesting supplementary management approaches may be appropriate. While the framework includes assumptions about IA containment, results offer new insight into emergent risk patterns and how management strategies alter them. Managers can adopt these methods to anticipate, quantify, and compare fine-scale policy outcomes.


2019 ◽  
Vol 34 (6) ◽  
pp. 1979-1998 ◽  
Author(s):  
Hsiao-Chung Tsai ◽  
Russell L. Elsberry

Abstract The original 7-day weighted analog intensity Pacific (WAIP) prediction technique is improved by developing a new version for the preformation stage and combining it with the bifurcation version that is especially for the intensification stage and the ending-storm stage WAIP. This combined three-stage WAIP includes a calibrated intensity spread designed to include 68% of the verifying intensities. In this demonstration of the optimum performance of the combined WAIP, the Joint Typhoon Warning Center (JTWC) best tracks, the time to formation (T2F), and ending-storm time are utilized as inputs along with the initial intensity [i.e., either 15 or 20 kt (1 kt ≈ 0.51 m s−1)]. In the new “Before Formation” (defined as 25 kt) stage of the WAIP, the intensity evolution is represented by a square function between the initial intensity and the T2F (25 kt), and very small mean absolute errors (MAEs) and intensity spreads are achieved. In the bifurcation version, correct selections between two cluster WAIP intensity evolutions lead to MAEs that slowly increase to 17 kt at 144 h, and the intensity spreads are relatively small as well. Because the ending-storm time constrains the analog selection in the WAIP, the MAEs begin to decrease after 72 h and are only 10 kt at 156 h. A case study is presented as to how an ensemble storm-track forecast along with the T2F could provide WAIP 7-day intensity predictions beginning in the preformation stage, which indicates the potential for earlier guidance for the JTWC intensity forecasts of western North Pacific tropical cyclones.


2019 ◽  
Author(s):  
Tirtha Banerjee ◽  
Warren Heilman ◽  
Scott Goodrick ◽  
Kevin Hiers ◽  
Rodman Linn

Wildfires burning more and more areas in North America can partly be attributed to fire exclusion activities in the past few decades which led to higher fuel accumulation. Mechanical thinning and prescribed burns are effective techniques to manage fuel loads and to establish a higher degree of control over future fire risk as well as to restore fire prone landscapes to their natural states of succession. However, given the complexity of interactions between fine scale fuel heterogeneity and wind, it is difficult to assess the success of thinning operations and prescribed burns. The present work addresses this issue systematically by simulating a fire starting from a simple fire line and moving through a vegetative environment where the midstory has been cleared in different degrees, leading to a canopy with almost no midstory, another with a sparse midstory and another with a thick midstory. The simulations are conducted for these three canopies under two different conditions, where the fuel moisture is high and where it is low. These six sets of simulations show widely different fire behavior, in terms of fire intensity, spread rate and consumption. To understand the physical mechanisms that lead to these differences, detailed analyses are conducted to look at wind patterns, mean flow and turbulent fluxes of momentum and energy. The analyses also lead to improved understanding of processes leading to high intensity crowning behavior in presence of a dense midstory. Moreover, this work highlights the importance of considering fine scale fuel heterogeneity, seasonality, wind effects and the associated fire-canopy-atmosphere interactions while considering prescribed burns and forest management operations.


Author(s):  
Arash Sadeghi ◽  
Elizabeth L Rose ◽  
Sylvie Chetty

This article aims to explore the under-researched topic of post-entry speed of internationalisation (PSI) in the context of international new ventures (INVs). We unbundle PSI and examine its relationship with both financial and non-financial export performance, considering three related, but conceptually distinct, dimensions of PSI: internationalisation intensity, spread and geographical diversity. Building on organisational learning theory, we highlight different mechanisms that contribute to post-entry performance outcomes among INVs. Our findings from a sample of 112 INVs in New Zealand provide evidence that the three dimensions of PSI are distinct and that they have different impacts on financial and non-financial export performance. This article contributes to the limited, yet growing body of literature on PSI by providing a deeper understanding of PSI and its constituent dimensions. In addition, this study offers new theoretical insights into how and why different dimensions of post-entry speed of internationalisation can contribute to stronger export performance.


Author(s):  
Kevin Ibeh ◽  
Marian V Jones ◽  
Olli Kuivalainen

This article introduces the Special Issue on post-entry performance of international new ventures (INVs), including the selected papers. It consolidates empirical knowledge on this topic area, particularly regarding the themes addressed in the Special Issue’s studies. These pertain to the influence on post-entry performance of the geographic scope, post-internationalisation speed dimensions of international intensity, spread, and diversity, learning capabilities, network resources, niche strategy, internationalisation timing and commitment mode of INVs. The article also addresses the issues associated with measuring post-entry performance among INVs and discusses next steps and future research implications.


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