Simplification of binomial coefficients

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Quick question, does anyone know how to simplify this series of binomial coefficients?

$$\sum_{m = 0}^{N} \binom{N}{m}^{\frac{1}{2}} \binom{N}{m+1}^{\frac{1}{2}}$$

Thanks for any assistance.

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I won't expect any nice closed form for the given sum, but the Cauchy-Schwarz inequality gives a reasonable upper bound: $$ \sum_{m=0}^{N-1}\sqrt{\binom{N}{m}}\sqrt{\binom{N}{m+1}} \leq \sqrt{\left(\sum_{m=0}^{N-1}\binom{N}{m}\right)\cdot\left(\sum_{m=0}^{N-1}\binom{N}{m+1}\right)} = 2^N-1.$$