Ten new exchange-traded funds (ETF) were launched last week, which is the first time in quite a while that so many ETFs have debuted at once. Each ETF takes a unique approach toward its respective investment niche, so they all deserve a closer look. Of course, even the most compelling new ETFs must still build sufficient trading volume before they’re suitable for investors.

Many consumers have enjoyed lower heating bills this winter, but a warmer-than-average season deserves only partial credit. Rock-bottom natural gas prices have contributed substantially to reducing consumer energy expenses. As a growing number of exploration and production companies have begun to employ innovative techniques to exploit unconventional reserves, a glut of natural gas produced from areas such as the Marcellus shale formation has depressed prices.

Despite these lower prices, there’s been a surge of interest in unconventional oil and gas plays. Now that vast amounts of US natural gas reserves have been discovered, natural gas is being discussed as a bridge fuel to wean the US from its dependence on oil and ultimately bolster its energy independence.

Market Vectors Unconventional Oil & Gas ETF (NYSE: FRAK) tracks a basket of 44 companies that generate at least 50 percent of their revenue from the production of unconventional oil and natural gas resources such as oil sands, shale gas or coal bed methane. The ETF’s portfolio includes holdings such as Occidental Petroleum Corp (NYSE: OXY), Canadian Natural Resources (NYSE: CNQ) and EOG Resources (NYSE: EOG).

Large-cap names dominate the portfolio with an 83.5 percent allocation. But the fund’s 15.9 percent allocation to mid-cap stocks offers some exposure to smaller companies. While unconventional energy plays are a global phenomenon, the ETF’s portfolio is geographically concentrated in the US, with 71.2 percent of assets allocated to US companies and 28.5 percent to Canadian companies.

The fund charges an annual expense ratio of 0.54 percent.

Oil and natural gas production is becoming increasingly difficult–most of the easy oil plays have been discovered and many new fields are more technologically challenging to develop due to their location. That means unconventional reserves will play a greater role in accommodating global energy demand. As such, this is a corner of the energy market that will likely experience heavy investment and significant merger and acquisition activity in the coming years, which make this ETF particularly attractive.

First Trust Advisors launched two new funds last week that apply the firm’s proprietary AlphaDEX stock selection methodology to global small-cap stocks.

First Trust Emerging Markets Small Cap AlphaDEX Fund (NYSE: FEMS) and First Trust Developed Markets ex-US Small Cap AlphaDEX Fund (NYSE: FDTS) both hold small-cap stocks that have been scored and selected based on a variety of value and growth factors. AlphaDEX is a fundamental stock selection methodology that attempts to identify stocks with the potential to generate returns above and beyond traditional index constituents.

The ex-US fund takes a global approach to portfolio construction and currently allocates 32 percent to Japanese companies. South Korea is the second largest geographical allocation at 18.3 percent of assets, followed by Hong Kong at 7.9 percent. While Asia is heavily represented in the fund’s portfolio, Canada, Australia and the United Kingdom also figure prominently in the fund’s geographical exposure.

From a sector perspective, the fund’s methodology currently favors consumer discretionary names, which account for more than 23 percent of assets. Industrials account for another 18.1 percent of assets, followed by materials at 17.6 percent. The fund is relatively underweight in more defensive sectors such as utilities (1.1 percent) and telecoms (1.1 percent).

The ETF currently tracks a basket of 393 global small-cap names. The largest company has a market cap of $2.87 billion and the smallest has a market cap of $85 million, while the median market cap of the fund’s holdings is $608 million.

The emerging markets fund applies the same stock selection methodology to its geography, so its sector allocations are similar to the ex-US fund. The fund also has a similar tilt toward Asia. China accounts for 28.2 percent of assets, and Taiwan accounts for 25.3 percent of assets. Altogether, Asia accounts for almost 75 percent of assets, with small allocations toward emerging Europe (Russia, Poland and Turkey) and Brazil.

Given that the AlphaDEX methodology largely focuses on momentum, both funds are positioned to capitalize on continued global economic improvement. While a momentum-based methodology can suffer greatly during significant market pullbacks, it can also benefit from improving investor sentiment.

BlackRock also had a busy week with its launch of seven new specialty bond funds.

iShares Aaa – A Rated Corporate Bond Fund (NYSE: QLTA) tracks a basket of corporate bonds with ratings ranging from AAA to single-A. The fund charges a 0.15 percent annual expense ratio.

iShares Barclays US Treasury Bond Fund (NYSE: GOVT) tracks government bonds with at least one year left to maturity, including everything from short-term to long-term bonds. That approach makes this one of the few ETFs to track almost the full spectrum of government debt. The fund charges a 0.15 percent annual expense ratio, which makes it one of the least expensive government bond fund ETFs available.

Two new mortgage-backed bond funds were also added to the iShares fixed-income lineup. iShares Barclays CMBS Bond Fund (NYSE: CMBS) tracks commercial mortgage-backed securities and iShares Barclays GNMA Bond Fund (NYSE: GNMA) tracks residential mortgage-backed bonds issued by the Government National Mortgage Association.

The CMBS fund will only construct its portfolio from debt that is eligible for holding by pension plans, which ensures a high-quality portfolio. And GNMA bonds carry government backing in case of default. The CMBS fund charges a 0.25 percent annual expense ratio, while the GNMA fund charges a 0.32 percent annual expense ratio.

BlackRock also launched iShares Industrials Sector Bond Fund (NYSE: ENGN), iShares Financials Sector Bond Fund (NYSE: MONY) and iShares Utilities Sector Bond Fund (NYSE: AMPS). All three funds charge annual expense ratios of 0.30 percent, and are the first sector-specific, investment-grade bond ETFs. These offerings allow investors to fine-tune their exposure to particular sectors, while also moving beyond duration and credit quality when building a fixed-income allocation.

Portfolio Roundup

Over the past week, the European Central Bank (ECB) and private investors tentatively agreed to take a haircut on their Greek bond holdings. As a result, Greece will receive another EUR130 billion infusion of capital and stave off a potentially destabilizing default. Additionally, European officials have also floated the idea of increasing the region’s backstop for future fiscal emergencies from EUR500 billion to EUR750 billion.

That news led our holdings in both iShares MSCI Germany Index (NYSE: EWG) and iShares MSCI France Index (NYSE: EWQ) to jump by more than 3 percent over the past week. Although our position in the French fund is still down by about 10 percent, our position in the German fund has netted a gain of more than 14 percent since our initial recommendation in August.

We expect European authorities to successfully negotiate a resolution to the region’s debt crisis, however, there will likely be additional hiccups along the way. But it’s a positive sign that European policymakers are taking a more aggressive approach toward solving their debt woes.

Continue buying iShares MSCI Germany Index below 25 and iShares MSCI France Index below 30.