SOME RESULTS ON THE QUESTIONS OF KIT-WING YU

Majumder, Sujoy Korean Mathematical Society 2016 대한수학회논문집 Vol.31 No.2

The paper deals with the problem of meromorphic functions sharing a small function with its differential polynomials and improves the results of Liu and Gu [9], Lahiri and Sarkar [8], Zhang [13] and Zhang and Yang [14] and also answer some open questions posed by Kit-Wing Yu [16]. In this paper we provide some examples to show that the conditions in our results are the best possible.

An innovative vibration barrier by intermittent geofoam - A numerical study

Majumder, Mainak,Ghosh, Priyanka,Sathiyamoorthy, Rajesh Techno-Press 2017 Geomechanics & engineering Vol.13 No.2

A new technique is proposed to obtain more effective screening efficiency against the ground vibration using intermittent geofoam (IF) in-filled trench. The numerical analysis is performed by employing two-dimensional finite element method under dynamic condition. Vertically oscillated strip foundation is considered as the vibration source. In presence of the ground vibration, the vertical displacements at different locations (pick-up points) along the ground surface are captured to determine the amplitude reduction factor (ARF), which helps to assess the efficiency of the vibration screening technique. The efficiency of IF over continuous geofoam (CF) in-filled vibration barriers is assessed by varying the geofoam density, the location of trench and the frequency of excitation. The results from this study indicate that a significant reduction in ARF can be achieved by using intermittent geofoam as compared to continuous geofoam. Further, it is noticed that the efficiency of IF increases with an increase in the frequency of the vibrating source. These encouraging results put forward the potential of utilising intermittent geofoam as a vibration screening material.

A RESULT ON A CONJECTURE OF W. LÜ, Q. LI AND C. YANG

Majumder, Sujoy Korean Mathematical Society 2016 대한수학회보 Vol.53 No.2

In this paper, we investigate the problem of transcendental entire functions that share two values with one of their derivative. Let f be a transcendental entire function, n and k be two positive integers. If $f^n-Q_1$ and $(f^n)^{(k)}-Q_2$ share 0 CM, and $n{\geq}k+1$, then $(f^n)^{(k)}{\equiv}{\frac{Q_2}{Q_1}}f^n$. Furthermore, if $Q_1=Q_2$, then $f=ce^{\frac{\lambda}{n}z}$, where $Q_1$, $Q_2$ are polynomials with $Q_1Q_2{\not\equiv}0$, and c, ${\lambda}$ are non-zero constants such that ${\lambda}^k=1$. This result shows that the Conjecture given by W. $L{\ddot{u}}$, Q. Li and C. Yang [On the transcendental entire solutions of a class of differential equations, Bull. Korean Math. Soc. 51 (2014), no. 5, 1281-1289.] is true. Also we exhibit some examples to show that the conditions of our result are the best possible.

Olax psittacorum (Lam.) Vahl. (Olacaceae): current status and future prospects as an herbal plant

Majumder Raja,Adhikari Lopamudra,Dhara Moonmun 경희대학교 융합한의과학연구소 2022 Oriental Pharmacy and Experimental Medicine Vol.22 No.2

Olax psittacorum (Lam.) Vahl. traditionally used by the tribal community of ‘INDIA’ to heal conditions such as pain, psoriasis, mouth-ulcer, anemia, constipation as well as diabetes. Documented scientific shreds of evidence like antipyretic, anti-inflammatory, antimicrobial, anti-viral, anti-cancer, toxicity profile improved its medicinal value. Chromatographic evaluation (GC–MS) proven near about presence of 25 compounds. Among them, hexadecanoic methyl ester, β-sitosterol, phytol, methyl salicylate, 13-docosenamide, and oleanolic acid are significant and contribute to its successful medicinal properties. The toxicity study also revealed the safety of the consumption of the leaf part. Still, consecutive gaps need to be exploring to gather evidence of its contribution to curing different ailments, especially upon the ulcer, anemia, and identification of the presence of lead compounds as an upcoming future research proposal. The ‘Internet Scholar’, ‘Study Guide’, ‘PubMed’, ‘ScienceDirect’, ‘Scopus’, and ‘Sodhganga’ web site have been accessed to gather information about detailed scientific research as well as traditional information from authenticated sources that have been published in the English language. The various folklore claimed medicinal properties like anti-ulcer, aphthous ulcer, analgesic, anti-diabetic, anti-anemic, etc. yet to be justified scientifically with lead compounds that can support the rationality being used as folklore. This plant could be a good choice to explore its importance within the pharmacognostic field of drug development and might be a better source of herbal derived lead compounds which can help to heal ulcer or anemia that can effectively make a credible addition to treatment among the civilization as a natural source of therapeutic compounds.

Gene Expression Patterns of Spleen, Lung and Brain with Different Radiosensitivity in C57BL6 Mice

Majumder Md. Zahidur Rahman,Lee, Woo-Jung,Lee, Su-Jae,Bae, Sang-Woo,Lee, Yun-Sil The Korean Association for Radiation Protection 2005 방사선방어학회지 Vol.30 No.4

Although little information is available on the underlying mechanisms, various genetic factors have been associated with tissue-specific responses to radiation. In the present study, we explored the possibility whether organ specific gene expression is associated with radiosensitivity using samples from brain, lung and spleen. We examined intrinsic expression pattern of 23 genes in the organs by semi-quantitative RT-PCR method using both male and female C57BL/6 mice. Expression of p53 and p21, well known factors for governing sensitivity to radiation or chemotherapeutic agents, was not different among the organ types. Both higher expression of sialyltransferase, delta7-sterol reductase, leptin receptor splice variant form 12.1, and Cu/Zn superoxide dismutase (SOD) and lower expression of alphaB crystalline were specific for spleen tissue. Expression level of glutathione peroxidase and APO-1 cell surface antigen gene in lung tissue was high, while that of Na, K-ATPase alpha-subunit, Cu/ZnSOD, and cyclin G was low. Brain, radioresistant organ, showed higher expressions of Na, K-ATPase-subunit, cyclin G, and nucleolar protein hNop56 and lower expression of delta7-sterol reductase. The result revealed a potential correlation between gene expression patterns and organ sensitivity, and Identified genes which might be responsible for organ sensitivity.

Impacts of COVID-19 lockdown on ambient air quality: Statistical analyses of available data on urban West Bengal (India)

Majumder, Rajib Techno-Press 2021 Advances in environmental research Vol.10 No.2

COVID-19 pandemic and consequent unavoidable lockdown left an unprecedented shock on social and economic life. Present study aimed to evaluate the impacts of COVID-19 lockdown on the ambient air quality of urban areas of eastern Indian state West Bengal. During lockdown period, Air Quality Index (AQI) was mostly found in 'Good' or 'Satisfactory' and sometimes, in 'Moderate' categories, and rarely, in 'poor' category. AQI was in 'Good' category for most of the lockdown span at Siliguri (67%) followed by Kolkata (44%), Howrah (38%) and Asansol (25%). Based on average AQI ranges: lockdown period (48.68- 62.12) < same period before 1 year (75.09-89.81) < Period 3 months before lockdown (175-206), it can be stated that AQI category was better during lockdown compared to the other two at all study areas. In Kolkata overall air pollutant levels except ozone (p>0.05) decreased significantly during lockdown. Similarly, PM_2.5, PM₁₀ and NO₂ level reduced in Howrah. Beside, no significant changes observed for NH₃ and SO₂ concentration in Howrah compared to one year before. Apart from PM_2.5, NO₂, NH₃ and SO₂ level of previous year, mean concentration of PM₁₀, CO, O₃ showed significant drop at Siliguri during lockdown. Ambient air quality parameters except SO₂ showed remarkable decline in Asansol also during lockdown. It can be concluded that COVID-19 lockdown exerted positive effects from environmental health perspective. It improved overall ambient air quality parameters of urban areas of West Bengal. Proper planning and policy making should be given utmost priority to control air pollution in the present 'new normal' COVID-19 scenario.

A RESULT ON AN OPEN PROBLEM OF LÜ, LI AND YANG

Majumder, Sujoy,Saha, Somnath Korean Mathematical Society 2021 대한수학회보 Vol.58 No.4

In this paper we deal with the open problem posed by Lü, Li and Yang [10]. In fact, we prove the following result: Let f(z) be a transcendental meromorphic function of finite order having finitely many poles, c₁, c₂, …, c_n ∈ ℂ\{0} and k, n ∈ ℕ. Suppose fⁿ(z), f(z+c₁)f(z+c₂) ⋯ f(z+c_n) share 0 CM and fⁿ(z)-Q₁(z), (f(z+c₁)f(z+c₂) ⋯ f(z+c_n))^(k) - Q₂(z) share (0, 1), where Q₁(z) and Q₂(z) are non-zero polynomials. If n ≥ k+1, then $(f(z+c_1)f(z+c_2)\;{\cdots}\;f(z+c_n))^{(k)}\;{\equiv}\;{\frac{Q_2(z)}{Q_1(z)}}f^n(z)$. Furthermore, if Q₁(z) ≡ Q₂(z), then $f(z)=c\;e^{\frac{\lambda}{n}z}$, where c, λ ∈ ℂ \ {0} such that e^{λ(c₁+c₂+⋯+c_n)} = 1 and λ^k = 1. Also we exhibit some examples to show that the conditions of our result are the best possible.

Manufacturing quality improvement and setup cost reduction in a vendor-buyer supply chain model

Majumder, Arunava,Guchhait, Rekha,Sarkar, Biswajit Inderscience Enterprises Ltd. 2017 European journal of industrial engineering Vol.11 No.5

<P>Quality improvement and setup cost reduction of any production system are endless procedure. Customer's demand is always intended to have the best quality product and the industries always try to improve the quality of products. This paper develops a two-echelon supply chain model with quality improvement of products and setup cost reduction under controllable lead time. The lead time demand follows a normal distribution and in the second case, it does not consider any specific distribution except a mean and standard deviation. Both models are solved analytically to obtain global solution. Two improved iterative algorithms are developed in order to obtain the optimal results of decision variables numerically to minimise the total system cost. The expected value of additional information is calculated to show the financial effect for collecting the information about lead time demand distribution. Some numerical examples and sensitivity analysis are given to illustrate the model.</P>

Modelling traveller response to variable message sign

Joydip Majumder,Khandkar Nurul Habib,Lina Kattan,Tak Shing Fung 서울시립대학교 도시과학연구원 2013 도시과학국제저널 Vol.17 No.2

Rapid traffic growth in Calgary has put increased pressure in city's roadway network, especially on Deerfoot Trail which provides a fast access to north–south potion of the city. The city disseminates traffic information in Deerfoot through variable message sign (VMS) in case of major delays and usually diverts traffic to alternate parallel arterials. However, the reroute tendency of travellers significantly affects the diversion pattern at the VMS locations and this research targets the frequent users of Deerfoot Trail and investigates their rerouting tendency in light of important trip attributes drivers might associate with their trips. A total of 471 responses are collected from frequent users of Deerfoot Trail through a questionnaire survey and the analysis is focused on developing a relationship between reroute tendency and a set of explanatory variables, using generalized ordered logit (GOLOGIT) model and partially generalized regression models. The results have led to the conclusion that in addition to various socio-economic attributes, network familiarity and information access characteristics; trip characteristics also possess significant influences in rerouting decision-making. The study also proposes several implications for better design and operation of advanced traveller information systems and future effort on model estimation in light of the finding of the study.

Preclinical evaluation of Kali Haldi (Curcuma caesia): a promising herb to treat type-2 diabetes

Poulami Majumder,Pallab Kanti Haldar,Suchandra Mazumder,Mainak Chakraborty,Srila Ghosh Chowdhury,Samit Karmakar 경희대학교 융합한의과학연구소 2017 Oriental Pharmacy and Experimental Medicine Vol.17 No.2

The methanol extract of Curcuma caesia (MECC) rhizome showed antidiabetic activity by lowering blood glucose in in vivo studies and controlled intestinal absorption of monosaccharides by inhibiting alpha amylase and alpha glucosidase. It also enhanced the glucose uptake in yeast cells, proving proper glucose utilization. The IC50 values of MECC were found to be 442.92 ± 10.05 μg/ml and 95.40 ± 9.74 μg/ml in alpha amylase and alpha glucosidase inhibition respectively. The extract has effective antioxidant activities, by successfully scavenging free radicals like superoxide and hydroxyl ions. The histopathological studies of pancreas showed gradual healing after treatment.