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We study a set of voting problems where given an election E = (C , Π V) (where C is the set of candidates and Π V is a set of votes), and a non-empty subset of candidates J , the question under consideration is: Can we modify the election in a way so that none of the candidates in J wins the election? The modification operations allowed are that of either adding or deleting some candidates. Yang and Wang (2017) [44] introduced these problems as the Resolute Control problem , a generalization of the destructive control problem where J is a singleton. They studied parameterized complexity of Resolute Control for voting rules Borda (both addition and deletion), Maximin (addition), and Copeland (both addition and deletion). They primarily consider | J | as parameter. In this paper we study Resolute Control parameterized by the other natural parameters viz., the number of candidates added or deleted. We show that the Resolute Control for Borda (both addition and deletion), Maximin (addition) and Copeland (deletion) are W[2]-hard. We complement this by showing that when the number of voters is odd, Copeland (deletion) is FPT parameterized by the sum of the number of deleted candidates and the size of the feedback arc set of the majority graph of the election. [ABSTRACT FROM AUTHOR]

Water scarcity rises as the level of water pollution continues to increase with the progress of urbanization, industrialization and exponential growth of population. Therefore, saline water of the sea should also be made suitable rather than river water to meet the huge global demand of clean and safe drinking water. Pervaporation (PV) desalination, among many purification and separation processes, is a promising technology to reduce the crisis of global drinking water supply. From this perspective, the key success of PV desalination relies on its remarkable salt rejection from highly saline water with appropriate flux to obtain fresh water by using a suitable membrane. In this review we aim to provide a comprehensive assessment of PV desalination membrane materials, transport phenomena, the advantages of the process over comparable technologies (e.g., fractional distillation, membrane distillation, reverse osmosis) and the advantages of crosslinking during the preparation of composite membranes. This review further highlights the advantages of inorganic ceramic substrates as a support of composite membranes and the use of hydrophilic polymers as active layer for preparing stable and robust crosslinked PV desalination membranes. [ABSTRACT FROM AUTHOR]

Water scarcity rises as the level of water pollution continues to increase with the progress of urbanization, industrialization and exponential growth of population. Therefore, saline water of the sea should also be made suitable rather than river water to meet the huge global demand of clean and safe drinking water. Pervaporation (PV) desalination, among many purification and separation processes, is a promising technology to reduce the crisis of global drinking water supply. From this perspective, the key success of PV desalination relies on its remarkable salt rejection from highly saline water with appropriate flux to obtain fresh water by using a suitable membrane. In this review we aim to provide a comprehensive assessment of PV desalination membrane materials, transport phenomena, the advantages of the process over comparable technologies (e.g., fractional distillation, membrane distillation, reverse osmosis) and the advantages of crosslinking during the preparation of composite membranes. This review further highlights the advantages of inorganic ceramic substrates as a support of composite membranes and the use of hydrophilic polymers as active layer for preparing stable and robust crosslinked PV desalination membranes. [ABSTRACT FROM AUTHOR]

Balanced Stable Marriage (BSM) is a central optimization version of the classic Stable Marriage (SM) problem. We study BSM from the viewpoint of Parameterized Complexity. Informally, the input of BSM consists of n men, n women, and an integer k. Each person a has a (sub)set of acceptable partners, A (a) , whom a ranks strictly; we use p a (b) to denote the position of b ∈ A (a) in a 's preference list. The objective is to decide whether there exists a stable matching μ such that balance (μ) ≜ max ⁡ { ∑ (m , w) ∈ μ p m (w) , ∑ (m , w) ∈ μ p w (m) } ≤ k. In SM , all stable matchings match the same set of agents, A ⋆ which can be computed in polynomial time. As balance (μ) ≥ | A ⋆ | 2 for any stable matching μ , BSM is trivially fixed-parameter tractable (FPT) with respect to k. Thus, a natural question is whether BSM is FPT with respect to k − | A ⋆ | 2. With this viewpoint in mind, we draw a line between tractability and intractability in relation to the target value. This line separates additional natural parameterizations higher/lower than ours (e.g., we automatically resolve the parameterization k − | A ⋆ | 2). The two extreme stable matchings are the man-optimal μ M and the woman-optimal μ W. Let O M = ∑ (m , w) ∈ μ M p m (w) , and O W = ∑ (m , w) ∈ μ W p w (m). In this work, we prove that • BSM parameterized by t = k − min ⁡ { O M , O W } admits (1) a kernel where the number of people is linear in t , and (2) a parameterized algorithm whose running time is single exponential in t. • BSM parameterized by t = k − max ⁡ { O M , O W } is W[1]-hard. [ABSTRACT FROM AUTHOR]

In this paper, we study the NP-complete colorful variant of the classic matching problem, namely, the Rainbow Matching problem. Given an edge-colored graph G and a positive integer k, the goal is to decide whether there exists a matching of size at least k such that the edges in the matching have distinct colors. Previously, in [MFCS'17], we studied this problem from the view point of Parameterized Complexity and gave efficient FPT algorithms as well as a quadratic kernel on paths. In this paper we design a quadratic vertex kernel for Rainbow Matching on general graphs; generalizing the earlier quadratic kernel on paths to general graphs. For our kernelization algorithm we combine a graph decomposition method with an application of expansion lemma. [ABSTRACT FROM AUTHOR]

In this paper, we study the NP-complete colorful variant of the classical Matching problem, namely, the Rainbow Matching problem. Given an edge-colored graph G and a positive integer k, this problem asks whether there exists a matching of size at least k such that all the edges in the matching have distinct colors. We first develop a deterministic algorithm that solves Rainbow Matching on paths in time O ⋆ 1 + 5 2 k and polynomial space. This algorithm is based on a curious combination of the method of bounded search trees and a "divide-and-conquer-like" approach, where the branching process is guided by the maintenance of an auxiliary bipartite graph where one side captures "divided-and-conquered" pieces of the path. Our second result is a randomized algorithm that solves Rainbow Matching on general graphs in time O ⋆ (2 k) and polynomial-space. Here, we show how a result by Björklund et al. (J Comput Syst Sci 87:119–139, 2017) can be invoked as a black box, wrapped by a probability-based analysis tailored to our problem. We also complement our two main results by designing kernels for Rainbow Matching on general and bounded-degree graphs. [ABSTRACT FROM AUTHOR]

In this paper we consider a problem that arises from a strategic issue in the stable matching model (with complete preference lists) from the viewpoint of exact-exponential time algorithms. Specifically, we study the STABLE EXTENSION OF PARTIAL MATCHING (SEOPM) problem, where the input consists of the complete preference lists of men, and a partial matching. The objective is to find (if one exists) a set of preference lists of women, such that the men-optimal Gale-Shapley algorithm outputs a perfect matching that contains the given partial matching. Kobayashi and Matsui (Algorithmica 58:151-169, 2010) proved this problem is NP-complete. In this article, we give an exact-exponential algorithm for SEOPM running in time 2O(n), where n denotes the number of men/women. We complement our algorithmic finding by showing that unless Exponential Time Hypothesis (ETH) fails, our algorithm is asymptotically optimal. That is, unless ETH fails, there is no algorithm for SEOPM running in time 2o(n). Our algorithm is a non-trivial combination of a parameterized algorithm for SUBGRAPH ISOMORPHISM, a relationship between stable matching and finding an out-branching in an appropriate graph and enumerating all possible non-isomorphic out-branchings. Our results cover both the cases when the preference lists are strict and complete, and when they are strict but possibly incomplete. [ABSTRACT FROM AUTHOR]

For a positive integer c, a graph G is said to be c-closed if every pair of nonadjacent vertices in G have at most c 1 neighbors in common. The closure of a graph G, denoted by cl(G), is the least positive integer c for which G is c-closed. The class of c-closed graphs was introduced by J. Fox, T. Roughgarden, C. Seshadhri, F. Wei, and N. Wein [Proceedings of the International Colloquium on Automata, Languages, and Programming (2018), 55; SIAM J. Comput., 49 (2020), pp. 448--464]. T. Koana, C. Komusiewicz, and F. Sommer [Proceedings of the European Symposium on Algorithms (2020), 65; SIAM J. Discrete Math., 36 (2022), pp. 2798--2821] started the study of using cl(G) as an additional structural parameter to design kernels for problems that are W-hard under standard parameterizations. In particular, they studied problems such as Independent Set, Induced Matching, Irredundant Set, and (Threshold) Dominating Set and showed that each of these problems admits a polynomial kernel when parameterized either by k + c or by k for each fixed value of c. Here, k is the solution size and c = cl(G). The work of Koana et al. left several questions open, one of which was whether the Perfect Code problem admits a fixed-parameter tractable (FPT) algorithm and a polynomial kernel on c-closed graphs. In this paper, among other results, we answer this question in the affirmative. Inspired by the FPT algorithm for Perfect Code, we further explore two more domination problems on the graphs of bounded closure. The other problems that we study are Connected Dominating Set and Partial Dominating Set. We show that Perfect Code and Connected Dominating Set are fixed-parameter tractable when parameterized by k + cl(G), whereas Partial Dominating Set, parameterized by k, is W[1]-hard even when cl(G) = 2. We also show that for each fixed c, Perfect Code admits a polynomial kernel on the class of c-closed graphs. And we observe that Connected Dominating Set has no polynomial kernel even on 2-closed graphs unless NP\subseteq co-NP/poly. [ABSTRACT FROM AUTHOR]

This paper takes a holistic look at the media sector and establishes that press freedom along with reach reduces political instability. Greater reach of media furthers the cause of a free press. It generates an informed populace and increases government responsiveness. The hypothesis is supported by multiple econometric specifications and the results remain robust. [ABSTRACT FROM AUTHOR]

We measure the critical scattering length for the appearance of the first three-body bound state, or Efimov three-body parameter, at seven different Feshbach resonances in ultracold 39K atoms. We study both intermediate and narrow resonances, where the three-body spectrum is expected to be determined by the nonuniversal coupling of two scattering channels. Instead, our observed ratio of the three-body parameter with the van der Waals radius is approximately the same universal ratio as for broader resonances. This unexpected observation suggests the presence of a new regime for three-body scattering at narrow resonances. [ABSTRACT FROM AUTHOR]

In our paper we establish foreign direct investment (FDI) as a major determinant of media freedom. Global integration can strengthen the media sector financially, make it technologically enhanced and can also improve the economic environment as a whole. This, in turn, would work towards the enhancement of media freedom. The sample includes high, middle and low income economies. Using a panel of 115 countries over a period of 20 years, our results reveal that FDI is an absolute necessity for a free and efficient media. The results are robust to various alternate specifications and inclusion of additional control variables. [ABSTRACT FROM AUTHOR]

We discuss the expansion dynamics under mean-field repulsion of an array of 87Rb Bose-Einstein condensates produced in an all-optical scheme involving 1D lattice with nearly 105 atoms, after fast evaporative cooling of just about 1 s. Single site occupation exceeds 2 × 104 in our experiments. The possibility of transition to two-dimensionality was also investigated. The expansion behavior of the high density multiple micro-condensates produced directly in the CO2 laser 1D optical lattice, with a lattice spacing of 5.3 μm, agrees well with a numerical simulation based on the mean-field theory. [ABSTRACT FROM AUTHOR]

We describe the realization of Bose-Einstein condensates (BEC) of 87Rb atoms with relatively large number of atoms at high density, in laser-optical traps in our laboratory. Starting from a giant magneto-optical trap containing nearly 1010 atoms, we transfer about 5 x 107 atoms into the optical dipole trap formed by crossing two high-power focused CO2 laser beams. BEC containing about 105 atoms was produced by forced evaporative cooling of the atomic sample in the crossed optical trap down to about 140 nK, in just about a second. The BEC was also produced in a 1D optical lattice formed by the standing wave of a retroreflected focused CO2 laser beam, with about 80,000 atoms in the condensate. Effects of mean-field interaction characteristic of BEC were observed in the expansion dynamics of the condensate. We discuss both the techniques and the innovations that enabled the efficient execution of the multiple steps involved in producing the BEC, starting from a thermal sample of rubidium gas. [ABSTRACT FROM AUTHOR]

• Amine functionalized composite membranes were prepared on tubular ceramic support. • Prepared NF membranes showed high removal efficiency of As(V), Cr(VI) and Cu(II). • EDTA modified membrane showed lower pore size and increased hydrophilicity. • XPS study confirms partial reduction of heavy metals on membrane surface. • The membrane is promising to treat heavy metal contaminated waste water. Novel amine functionalized composite membranes were prepared over tubular ceramic substrate using facile dip-coating and cross-flow filtration approach. The two fabricated membranes, P-60S and P-60S-EDTA with polyethyleneimine (PEI) and EDTA-modified PEI as functional layers respectively, were characterized in terms of EDX, FTIR, XPS, FESEM, AFM and contact angle analyses which confirmed their stable physical and chemical structure for use in high pressure application. Clean water permeability and MWCO study revealed the superior permeability and rejection efficiency of the P-60S-EDTA compared to the P-60S membrane. Incorporation of bulky EDTA molecules in the membrane functional layer simultaneously decreased pore size and increased membrane hydrophilicity. The removal of As(V), Cr(VI) and Cu(II) heavy metals by both membranes were found to be highly pH dependent and overall rejection improved in case of P-60S-EDTA membrane [99.82% for Cu(II), 96.75% for As(V) and 97.22% for Cr(VI)]. Interestingly, rejection of As(V) and Cr(VI) was significantly improved in presence of Cu(II) due to volume resistance provided by EDTA-Cu(II) complex towards the passage of other heavy metal ions. Excellent stability of P-60S-EDTA membrane in continuous operation of 36 h in both ideal and practical water environment suggests its promising application in real field heavy metal contaminated waste water treatment. [ABSTRACT FROM AUTHOR]

In this Note we describe the design, construction, and calibration of an electronic wavelength-meter using a wavelength-sensitive dual-output photodiode. The device was constructed using electronic circuitry and then calibrated using various laser sources in the wavelength range 500-850 nm. This is an inexpensive device compared to the other similar devices available commercially. It is very useful for the determination of the wavelengths of diode lasers. It works well with multi-mode light, and there are no stringent alignment requirements. It is extremely compact and essentially a "pocket wavemeter." The wavelength range for the operation of the wavelength-meter is 450 to 900 nm and it gives 1-3 nm accuracy, depending on the wavelength. [ABSTRACT FROM AUTHOR]

We present the design, implementation, and detailed experimental characterization and comparison with numerical simulations of two-dimensional magneto-optical traps (MOTs) of bosonic 23Na and 39K atoms for loading the cold atomic mixture in a dual-species 3DMOT with a large number of atoms. We report our various measurements pertaining to the characterization of two 2D+MOTs via the capture rate in the 3DMOT and also present the optimized parameters for the best performance of the system of the cold atomic mixture. Under the optimized condition, we capture more than 3 × 101039K atoms and 5.8 × 10823Na atoms in the 3DMOT simultaneously from individual 2D+MOTs with a capture rate of 5 × 1010 and 3.5 × 108 atoms/sec for 39K and 23Na, respectively. We also demonstrate improvements of more than a factor of 5 in the capture rate in the 3DMOT from the cold atomic sources when a relatively high-power ultraviolet light is used to cause light-induced atomic desorption in the 2D+MOT glass cells. A detailed study of the light assisted interspecies cold collisions between the co-trapped atoms is presented, and interspecies loss coefficients have been determined to be βNaK ∼ 2 × 10−12 cm3/sec. The cold atomic mixture would be useful for further experiments on quantum simulation with ultra-cold quantum mixtures in optical potentials. [ABSTRACT FROM AUTHOR]

We study the parameterized complexity of NP-hard optimization versions of Stable Matching and Stable Roommates in the presence of ties and incomplete lists. These problems model many real-life situations where solutions have to satisfy certain predefined criterion of suitability and compatibility. Specifically, our objective is to maximize/minimize the size of the stable matching. Our main theorems state that Stable Matching and Stable Roommates admit small kernels. Consequently, we also conclude that Stable Matching is fixed-parameter tractable ( FPT ) with respect to solution size, and that Stable Roommates is FPT with respect to a structural parameter. Finally, we analyze the special case where the input graph is planar. [ABSTRACT FROM AUTHOR]

In December 2012, a young student was gang-raped on a bus in Delhi. Since then media attention has been directed toward raising awareness about crimes against women in India. But data shows that domestic violence and not rape is India’s number one reported crime over the last decade. An incidence of domestic violence, legally defined as “cruelty by husband or his relatives,” is reported once every five minutes. This paper attempts to prospectively examine the association between several risk factors and domestic violence in India. We utilize a comprehensive, national database, viz. the National Family Health Survey (NFHS-3) and focus on a sample of 69704 ever-married women between the ages of 15-49. A limited dependent variable model was used to estimate the effects. The dependent variable is a dichotomous variable indicating whether a respondent has faced any form of violence (both physical and emotional). Benchmark results and robustness checks indicate that several socio-economic and demographic factors are significantly associated with the likelihood of facing domestic violence. Factors that matter are educational attainment by the female as well as the husband, her employment status, the employment status of the husband, and demographic factors like caste and religion. A broad investigation indicates that among a comprehensive set of socio-economic and demographic variables that affect the susceptibility of ever-married women to domestic violence, women’s exposure to intergenerational violence, and alcohol consumption by the partner emerge as significant risk factors. The results remain robust even with choice of sub-samples based on educational differences between the partners. There is ample anecdotal evidence to suggest that excessive alcohol consumption is a national problem. Policy options have varied between outright prohibition and the use of tax instruments to curb excessive alcohol consumption. Apart from these, other positive interventions could emphasize on adverse health impacts and children’s well-being to bring about a sustainable behavioral change in partners. In addition to empowering women to break the cycle of domestic violence, one possible policy solution calls for the use of medical settings as an intervention point for children exposed to such violence. In order to support practitioners, NGOs and governmental agencies could identify best practices and disseminate such information to communities. [ABSTRACT FROM AUTHOR]

Previous literature stresses the importance of free media for economic development. By its nature TV, radio, and newspapers cross borders, allowing citizens to easily sample media from neighboring countries. This creates pressure for domestic reform and spreads media freedom between countries. Using spatial econometric techniques, and a sample of 102 countries, we test for the presence of geographic spillovers in media freedom. We find that a country's level of media freedom significantly depends on its neighbors. Countries ‘catch’ approximately 20 percent of their media freedom from neighboring countries. Our results are robust to alternative specifications and measures of press freedom. [ABSTRACT FROM AUTHOR]