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Water is an essential element on earth, which provides human a variety of services in domestic use, agriculture, or industries. However, some serious health risks of drinking water are associated with microbial contamination, particularly with fecal matter. Therefore, microbial quality assessment is considered to be a necessary component of water quality assessment. This study investigates microbial contamination of water distributary system around the city by comparing groundwater (GW) and tap water (TW) quality in Quetta city. 31 GW samples and 31 TW samples were collected in the study area during the months of September, October, and November. Fecal coliform test was carried out in laboratory and their average total coliform contamination was computed. Results showed that the TW sample were all contaminated by coliform except for Chiltan town, hence are not considered suitable for drinking without any treatment according to WHO drinking water quality standards. The average coliform concentrations were 12 in Quetta main city, 11.6 in Jinnah town, 5.3 in Satallite town, 10 in Shahbaz town and 5 in Brewery town (0/100 mL CFU) and the TW samples from the three towns were even more contaminated with E.coli. Whereas among the GW, average microbial concentrations were 1.8 in Quetta main city, 2 in Satallite town, 1.4 in Shahbaz town, and 0.4 in Chiltan town (0/100 mL CFU), respectively, which shows that the contamination is occurring within the water distributary pipeline system when the water flows through the pipelines. Moreover, this research will be valuable for researchers and administrative authorities to conduct elaborative studies, and develop new policies to prevent further deterioration of drinking water in the water distribution system by pathogenic microorganisms and ensure safe drinking water to the public of Quetta city.

Negishi cross-coupling reaction is a familiar reaction for the formation of carbon–carbon bonds that couples organic halides or triflates with organozinc compounds. Palladium is used as a metal catalyst, sometimes nickel can also be used, e.g. Pd2(dba)3, PdCl2(P(otol)3)2, Pd(DPEPhos)Cl2, Ni(PPh3)2Cl2, etc. This reaction has vast applications in organic synthesis as many natural products and biologically active compounds can be obtained through this reaction. The main aim of this review is to summarize the recent synthetic applications of the Negishi reaction reported since 2011 which may be helpful to the researchers working on the development of mild and sustainable strategies regarding the synthesis of pharmaceutically important scaffolds. [ABSTRACT FROM AUTHOR]

Many urban centres worldwide must depend on groundwater resources for domestic water supply due to less deteriorate and accessibility. The unplanned population growth and anthropogenic activities has been affected the sustainability of groundwater resources globally. Quetta, the provincial headquarter of largest province of Pakistan, is facing serious issues of water scarcity, decline and less recharge. The objective of current study is to identify groundwater recharge potential zone using latest techniques of multi criteria decision analysis based on geographic information system and remote sensing applications for the Quetta Valley. The satellite images and other data sources are used to develop the thematic layers, viz., land use land cover, drainage density, lineament density, soil, rainfall, slope, geology, and geomorphology of the study area using various tools within ArcGIS. By using multicriteria decision analysis technique, the thematic layers are integrated and weighted overlay index analysis is employed to rank the parameter by its influence on groundwater recharge. Based on multi criteria decision analysis technique, the weight is allocated to each significant parameter. The recharge zones map is categories into three categories: high, moderate, and poor zones base on groundwater recharge potential. The final map covers 48.9% high recharge area and moderate recharge area 28.2% while least recharge is observed in 22.9% area of total study area. The final map of potential groundwater recharge zone could help to suggest artificial recharge sites groundwater in the study area to sustain depleting groundwater resources which could be Urak, Balali, Jinnah Town, Killi Chiltan Lehri, Nawa Killi etc. The findings are useful for water resource development and management for provincial headquarter of biggest province of Pakistan. [ABSTRACT FROM AUTHOR]

The Russia–Ukraine war has reignited global debates on the role of nuclear weapons, particularly concerning security guarantees and deterrence. This article examines Pakistan's nuclear policy, which developed outside the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and was shaped by pressing regional security concerns, particularly Pakistan's relationship with India. Unlike non-nuclear-armed states such as Ukraine, which have relied on security assurances under the Budapest Memorandum, Pakistan's decision to pursue nuclear capabilities reflected a deep skepticism toward such external security commitments. While Pakistan's case is distinct in the country's development of nuclear weapons as a non-NPT state, it also serves to highlight the ongoing challenges faced by non-nuclear states within the global nonproliferation regime. Despite growing global attention to nuclear weapons in light of the Russia–Ukraine war, this article argues that the nonproliferation framework remains resilient, even as global conflicts test its boundaries. For non-nuclear-armed states, the path to nuclear weapons remains fraught with diplomatic, economic, and security barriers, suggesting that, while nuclear deterrence remains central for states such as Pakistan, widespread nuclear proliferation remains unlikely. [ABSTRACT FROM AUTHOR]

The Corey-Seebach reagent plays an important role in organic synthesis because of its broad synthetic applications. The Corey-Seebach reagent is formed by the reaction of an aldehyde or a ketone with 1,3-propane-dithiol under acidic conditions, followed by deprotonation with n-butyllithium. A large variety of natural products (alkaloids, terpenoids, and polyketides) can be accessed successfully by utilizing this reagent. This review article focuses on the recent contributions (post-2006) of the Corey-Seebach reagent towards the total synthesis of natural products such as alkaloids (lycoplanine A, diterpenoid alkaloids, etc.), terpenoids (bisnorditerpene, totarol, etc.), polyketide (ambruticin J, biakamides, etc.), and heterocycles such as rodocaine and substituted pyridines, as well and their applications towards important organic synthesis. [ABSTRACT FROM AUTHOR]

"Nuclear Governance in the Asia-Pacific" is a book that explores the importance of effective global nuclear governance in shaping public confidence in nuclear power, with a focus on the Asia-Pacific region. The book features contributions from experts in the field and covers topics such as regional nuclear governance, the role of the United States, nuclear education, and China's drive for nuclear energy. The authors emphasize the need for collaborations among states, institutions, and civil society to promote shared responsibility for nuclear safety and security. The book highlights the challenges faced by countries in the region and the importance of regional approaches and the involvement of multiple stakeholders in addressing governance challenges. [Extracted from the article]

In this study, we have investigated ciprofloxacin-based acetanilides for their in-vitro inhibitory study against gram +ve, -ve bacteria and serine protease activity. The compounds 4e and 4g showed excellent antibacterial activity against Bacillus subtilis with a zone of inhibition (ZI) values of 40 ± 0.9 mm, 37 ± 1.4 mm and with MIC values of 4.0 ± 0.78 mg/mL, 3.0 ± 0.98 mg/ML respectively, while 4a and 4i were found most active against Escherichia coli, with ZI values 38 ± 0.1 mm, 46 ± 1.8 mm and with MIC values of 1.0 ± 0.25 mg/mL, 1.0 ± 0.23 mg/mL respectively. All derivatives (4a-j) significantly inhibited the catalytic activity of serine protease, while 4a exhibited a maximum (100%) inhibitory effect at 96 minutes having 22.50 minutes t12 , and non-competitive inhibition with 0.1±0.00μM Ki. The IFD/MM-GBSA studies highlighted the binding mode of 4a for protease inhibition and indicated improved binding affinity with –107.62 kcal/mol of ΔGbind. [ABSTRACT FROM AUTHOR]

Sharpless asymmetric dihydroxylation is an important reaction in the enantioselective synthesis of chiral vicinal diols that involves the treatment of alkene with osmium tetroxide along with optically active quinine ligand. Sharpless introduced this methodology after considering the importance of enantioselectivity in the total synthesis of medicinally important compounds. Vicinal diols, produced as a result of this reaction, act as intermediates in the synthesis of different naturally occurring compounds. Hence, Sharpless asymmetric dihydroxylation plays an important role in synthetic organic chemistry due to its undeniable contribution to the synthesis of biologically active organic compounds. This review emphasizes the significance of Sharpless asymmetric dihydroxylation in the total synthesis of various natural products, published since 2020. [ABSTRACT FROM AUTHOR]

The traditional Ullmann reaction which represents the copper-catalyzed coupling between two aryl halides to build a C–C bond was first reported in 1901. Over the time, this reaction was widely applied in organic synthesis for the construction of a variety of carbon–heteroatom bonds using different types of catalysts such as palladium nanoparticles, palladium–iron nanoparticles, gold nanoparticles, and gold–copper nanoparticles. The present review describes the recent green methodologies of Ullmann reaction for C–C, C–N, C–O, and C–S bonds formation. Microwave/ultrasound irradiations, easily recoverable heterogeneous catalysts, solvent-free, and ligand-free parameters overcome the problems faced due to classically reported harsh reaction conditions of Ullmann coupling. All such developments with possible mechanistic insights reported since 2010 have been discussed in this review which gives a brief idea to the chemists for the scope, generality, and limitations of the Ullmann reaction. Moreover, considering these methodologies in view, many other exciting pathways can also be developed for the synthesis of different types of heterocycles, drug-like molecules, and natural products. Although a lot of work has been done on the Ullmann reaction, there is still tremendous scope in this field to look for recyclable catalysts, mild conditions, and substrate scope. Moreover, research regarding mechanistic aspects of the reaction can be improved by discovering new sustainable strategies as green procedures will continuously give a substantial impact on Ullmann chemistry. [ABSTRACT FROM AUTHOR]

Selenium-containing heterocycles play a pivotal role to construct a variety of pharmaceutically important molecules. They are also extensively used in the glass industry as well as to make different types of solar cells and photocells. Moreover, their extensive applications in multiple organic reactions due to their remarkable reactivity make them an interesting subject of research for scientists. Therefore, a variety of synthetic protocols for selenium-based molecules have been described mainly from 2010 to 2021 which have been compiled in this review. [ABSTRACT FROM AUTHOR]

The article discusses the categorization of weapons of mass destruction (WMD) and argues that the term can be misleading and misdirect resources. It specifically focuses on radiological weapons (RWs) and examines the programs of Egypt, Iraq, the Soviet Union, the United Kingdom, and the United States. The authors use a structured and focused comparison method to analyze the reasons for pursuing and ultimately renouncing RWs. They find that bureaucratic in-fighting and organizational politics played a significant role in inhibiting the deployment of RWs, and that the effectiveness and utility of these weapons were called into question. The article also highlights the obstacles to deterrence and emphasizes the importance of not disregarding the threat posed by RWs. [Extracted from the article]

Metal-catalyzed reactions play a vital part to construct a variety of pharmaceutically important scaffolds from past few decades. To carry out these reactions under mild conditions with low-cost easily available precursors, various new methodologies have been reported day by day. Sandmeyer reaction is one of these, first discovered by Sandmeyer in 1884. It is a well-known reaction mainly used for the conversion of an aryl amine to an aryl halide in the presence of Cu(I) halide via formation of diazonium salt intermediate. This reaction can be processed with or without copper catalysts for the formation of C–X (X = Cl, Br, I, etc.), C-CF3/CF2, C–CN, C–S, etc., linkages. As a result, corresponding aryl halides, trifluoromethylated compounds, aryl nitriles and aryl thioethers can be obtained which are effectively used for the construction of biologically active compounds. This review article discloses various literature reports about Sandmeyer-related transformations developed during 2000–2021 which give different ideas to synthetic chemists about further development of new and efficient protocols for Sandmeyer reaction. An updated compilation of new approaches for Sandmeyer reaction is described in this review to construct a variety of carbon-halogen, carbon-phosphorous, carbon-sulfur, carbon-boron etc. linkages. [ABSTRACT FROM AUTHOR]

Reformatsky reaction holds a prominent place in synthetic chemistry as it provides a unique route to build carbon-carbon bond. In this reaction, aldehydes or ketones react with α-halocarbonyl compounds in the presence of metal catalysts to produce β-hydroxy alkanoates. S. N. Reformatsky discovered this transformation in 1887 and it has a wide range of applications in the total synthesis of various natural compounds. In this account, attention has been placed on the utilization of Reformatsky reaction in the total synthesis of natural compounds, reported since 2013. [ABSTRACT FROM AUTHOR]

Fukuyama reaction for the synthesis of multifunctional aldehydes, secondary amines and ketones has gained considerable importance in synthetic organic chemistry because of mild reaction conditions. The use of thioesters in both Fukuyama aldehydes and ketones synthesis is highly attractive for organic chemists as they are easily accessible from corresponding carboxylic acids. Fukuyama–Mitsunobu reaction utilizes 2-nitrobenzenesulfonyl (Ns) for the protection/activation/deprotection of primary amines to afford secondary amines in good yields and high enantioselectivities. This review presents recent synthetic developments and applications of Fukuyama reaction for the synthesis of aldehydes, secondary amines and ketones. [ABSTRACT FROM AUTHOR]

A green ultrasound assisted convenient approach has been reported for the ring opening of epoxides. As a result, a series of N-phenyl piperazine and morpholine based β-amino alcohols has been synthesized under ultrasound irradiation in DMSO for 60 minutes at 70 °C. This methodology showed excellent tolerance with various epoxides and provided excellent yields upto 96%. All the synthetic derivatives (4a-e) (5c-d) significantly influence the catalytic activity of protease while 5d exhibited maximum (100%) inhibitory effect with a half-life of 40.76 minutes. Among the target derivatives, compound 4c exhibited significant antibacterial activity against Bacillus subtilis and Escherichia coli bacterial strains with zone of inhibition values 45 mm and 32 mm, respectively. [ABSTRACT FROM AUTHOR]

Spirocyclic compounds fascinate the synthetic chemists due to their privileged ring system and efficacy in drug discovery. Many natural compounds comprise spirocyclic moiety in their skeleton and are effective in pharmaceutical industry. Over the years, many synthetic methodologies have been established for the construction of spirocyclic compounds. In this review, recent synthetic approaches to accessing various spirocompounds comprising six-membered carbocycles/heterocycles have been summarized. [ABSTRACT FROM AUTHOR]

Kashmir is known to be a heaven on earth for centuries. This earthly paradise turns out to be a hell for the last seventy-three years of history. Kashmir conflict, on the contrary, remains a bone of contention amid India and Pakistan since independence. The Kashmir dispute is an extremely complicated phenomenon that offers an inflexible contest to the modern approaches of conflict resolution. The conflict of Kashmir needs a viable resolution because both antagonist states are nuclear powers of the region, which may have devastating consequences since it undoubtedly keeps the global and regional peace at risk. The end of this seemingly unending conflict demands unprejudiced and just efforts to create new opportunities for cooperation. No party at present exhibits willingness to leave its principled stance hurdling the possible solution of this dispute, although an agreement among three stakeholders can make the dream of Kashmir's self-determination come true. This research aims to analyze the possibilities of normalization of India and Pakistan's relationship while highlighting various options for peaceful resolution of the Kashmir conflict. In the present scenario, it would be necessary to condition Pakistan and India's people to reach out a workable solution to the Kashmir issue in a win/win situation by adopting a give and take strategy as a conflict resolution approach. [ABSTRACT FROM AUTHOR]

Fluoroquinolones are targets of interest due to their broad spectrum antibacterial activity. Structure-activity relationship (SAR) of fluoroquinolones clearly indicates that substitution at C-7 position enhances the lipophilicity of these scaffolds resultantly affording pharmacologically significant compounds. Therefore, various ciprofloxacinoxadiazole hybrids were synthesized and characterized by spectral analysis. Cytotoxic activity of these derivatives was assessed using human liver tumor cells (Huh7). One dose anticancer test results revealed moderate cytotoxicity of the newly synthesized compounds against this cell line. As the only compound 4a depicted comparatively lower cell viability value (81.91% using 100μg/mL concentration) than the other compounds. [ABSTRACT FROM AUTHOR]

Water is extremely important for human survival and economic development globally. The largest province of Pakistan, Balochistan, is facing drought conditions, water scarcity and quality issues, which has badly affected community livelihood and health. The agriculture sector contributes over 26% gross domestic product (GDP) of the country and engages 44% of the total labour force. Due to the steep slope, the limited surface is ephemeral. So, groundwater is the only option for various activities in 90% area of the province while 10% area has waterlogging and extremely bad-quality groundwater issues. Major reasons for limited research work on water issues across the province were because of security, political and socio-economic issues. Previous studies depict that groundwater quality in the entire province contains a high concentration of various contaminants and pathogens. Pakistan Economic Survey revealed in a study that over 50 million people across the country do not have access to safe water, and over 0.25 million children died due to polluted water. More than 72% of the rural population in Balochistan depends on dug wells and streams for drinking water. This review paper covers various anthropogenic factors that contaminate groundwater and surface water, uses and available overall water resources in the province. Previous studies indicate the public in Balochistan is facing health issues from contaminants such as arsenic, fluoride, pathogenic, etc. in drinking water. In this article, spatial maps show the spatial variation of pollutants, water table and geological formations. Balochistan can be divided into two regions, south and north, containing different climate and water availability conditions. Basin wise water monitoring system could be the best option to sustain water resources, and low delta crops reduce stress on groundwater. The stakeholders and active community participation and serious effects could help to overcome water issues. [ABSTRACT FROM AUTHOR]

A more lucid understanding of the implications of India's limited-war aims for Pakistan would help to articulate the nature of inadvertent and accidental escalation in the South Asian landscape, as well as the two-sided cycle of action and reaction between India and Pakistan. Keywords: escalation; technology; modernization; limited war; second strike capability; revisionism EN escalation technology modernization limited war second strike capability revisionism 243 247 5 09/23/22 20210201 NES 210201 In a 2020 reflection on Robert Jervis's seminal book, I The Meaning of the Nuclear Revolution i , Nina Tannenwald, while acknowledging the compelling logic of Jervis's theory, pointed to counterevidence that is repugnant to the tenets of the theory. The authors make this argument by surveying challenges to nuclear India, the steps it is taking to address those challenges, and the interactions among the members of the China--India-Pakistan nuclear triangle. [Extracted from the article]

Organic reactions under green conditions have become popular day by day because of increased use of harmful chemicals leading to environmental hazards. This review focuses the implementation of green chemistry in Suzuki–Miyaura, Heck, Stille and Chan–Lam cross-coupling reactions incorporating a variety of strategies in which ionic liquids, water and microwave irradiations are extensively used. [ABSTRACT FROM AUTHOR]

In the process, Budjeryn steers clear of treating the Belarusian, Kazakhstani or Ukrainian routes to denuclearization as the singular correct path towards nuclear disarmament. Budjeryn, a Ukrainian-American scholar, expertly uses archives to explore how Ukraine gave up the nuclear arsenal that it inherited after the collapse of the Soviet Union. [Extracted from the article]

Narang defines hedging as a strategy where the country 'intentionally refrains from actively developing nuclear weapons while simultaneously putting various pieces in place for a future nuclear weapons programme, such that it will be easier to weaponize if it becomes necessary' (p. 17). In a recent report on Iran's nuclear programme, American physicist David Albright argued that the country 'threatens the world with a program ready to produce nuclear weapons on-demand'. In the context of Iran, Narang's innovative account can help scholars and decision-makers make sense of the country's nuclear programme and influence Iran's policies in the future. [Extracted from the article]

Sonogashira cross coupling is a well-known reaction for the formation of carbon-carbon bond. It involves the coupling of aryl halides with terminal alkynes to synthesize versatile functionalized alkyne scaffolds having diverse applications. Many of the natural products and important pharmaceutical drugs can be obtained through this reaction. In this regard, hectic progress has been put by the synthetic chemists to make this cross coupling more effective. This review article discloses mild and environmental friendly reaction conditions of Sonogashira cross coupling developed during 2013-2018. [ABSTRACT FROM AUTHOR]

Aziridine ring opening reactions have gained tremendous importance in the synthesis of nitrogen containing biologically active molecules. During recent years, a great effort has been put forward by scientists toward unique bond construction methodologies via ring opening of aziridines. In this regard, a wide range of chiral metal- and organo-catalyzed desymmetrization reactions of aziridines have been reported with carbon, sulfur, oxygen, nitrogen, halogen, and other nucleophiles. In this review, an outline of methodologies adopted by a number of scientists during 2013-2017 for aziridine ring opening reactions as well as their synthetic applications is described. [ABSTRACT FROM AUTHOR]

This effort has been undertaken by one of India's most experienced foreign policy practitioners, Shivshankar Menon, in his voluminous book I India and Asian Geopolitics: The Past, Present i . Doing so would also help India fight poverty, hunger, and illiteracy, which, according to Menon, are critical to transforming India. It is important to note that while Menon's book gives a fairly comprehensive account of regional and global settings in which India must operate, it falls short in explaining why cooperation, not confrontation, is a must for India. [Extracted from the article]

Lamivudine (3TC; 2,3-dideoxy-3-thiacytidine) is a reverse transcriptase inhibitor and used for the treatment of human immunodeficiency virus-1 (HIV-1) and hepatitis B virus (HBV) infection. Because of its potent antiviral activity, chemists investigated a lot of methods for the synthesis of lamivudine and its derivatives. In this review, different strategies adopted by synthetic/medicinal chemists towards the synthesis of lamivudine and its derivatives have been summarized. [ABSTRACT FROM AUTHOR]

Ciprofloxacin is a broad-spectrum antibiotic that plays an important role in inhibiting the growth of both Gram-positive and Gram-negative bacteria. Medicinal chemists are extensively involved in the synthesis of novel ciprofloxacin derivatives, in search of new ciprofloxacin-based drugs with enhanced activity. This review article summarizes the major synthetic approaches involved in the synthesis of ciprofloxacin-based molecules. [ABSTRACT FROM PUBLISHER]

Review: 71 refs. [ABSTRACT FROM AUTHOR]

Transition metal-catalyzed C-H alkylation has appeared as a well-built tool for the step-economical transformations of inert C-H bonds. Keeping in view the growing importance of these reactions, an outline of the application of transition metal catalysis in C-H functionalization/late-stage diversification processes has been demonstrated. In this review, we have focused on metals such as palladium, gold, scandium, silver, rhenium and manganese playing role as catalysts in C-H alkylation. Various alkylating agents, e.g., alcohols, alkyl halides, alkenes, diazo compounds and boronic acids, etc., have been used to get the products in good yields. [ABSTRACT FROM AUTHOR]